Inhaled Hypertonic Saline In Adults Hospitalized For Exacerbation Of Cystic Fibrosis Lung Disease: A Retrospective Study For peer review only

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1 BMJ Open Inhaled Hypertonic Saline In Adults Hospitalized For Exacerbation Of Cystic Fibrosis Lung Disease: A Retrospective Study Journal: BMJ Open Manuscript ID: bmjopen Article Type: Research Date Submitted by the Author: -Sep- Complete List of Authors: Pezzulo, Alejandro; University of Iowa, Internal Medicine Stoltz, David; University of Iowa, Internal Medicine Hornick, Douglas; University of Iowa, Internal Medicine Durairaj, Lakshmi; University of Iowa, Internal Medicine <b>primary Subject Heading</b>: Secondary Subject Heading: Keywords: Drugs and medicines Cystic fibrosis < THORACIC MEDICINE, THERAPEUTICS, Respiratory infections < THORACIC MEDICINE BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright. -

2 Page of BMJ Open 0 0 Section/Topic Item # STROBE 0 (v) Statement Checklist of items that should be included in reports of cohort studies Recommendation Reported on page # Title and abstract (a) Indicate the study s design with a commonly used term in the title or the abstract Introduction (b) Provide in the abstract an informative and balanced summary of what was done and what was found Background/rationale Explain the scientific background and rationale for the investigation being reported Objectives State specific objectives, including any prespecified hypotheses Methods Study design Present key elements of study design early in the paper Setting Describe the setting, locations, and relevant dates, including periods of recruitment, exposure, follow-up, and data collection Participants (a) Give the eligibility criteria, and the sources and methods of selection of participants. Describe methods of follow-up (b) For matched studies, give matching criteria and number of exposed and unexposed Variables Clearly define all outcomes, exposures, predictors, potential confounders, and effect modifiers. Give diagnostic criteria, if Data sources/ measurement applicable * For each variable of interest, give sources of data and details of methods of assessment (measurement). Describe comparability of assessment methods if there is more than one group Bias Describe any efforts to address potential sources of bias - Study size Explain how the study size was arrived at Quantitative variables Explain how quantitative variables were handled in the analyses. If applicable, describe which groupings were chosen and why Statistical methods (a) Describe all statistical methods, including those used to control for confounding Results on January by guest. Protected by copyright. (b) Describe any methods used to examine subgroups and interactions (c) Explain how missing data were addressed (d) If applicable, explain how loss to follow-up was addressed (e) Describe any sensitivity analyses - BMJ Open: first published as./bmjopen on April. Downloaded from - -

3 BMJ Open Page of 0 0 Participants * (a) Report numbers of individuals at each stage of study eg numbers potentially eligible, examined for eligibility, confirmed eligible, included in the study, completing follow-up, and analysed (b) Give reasons for non-participation at each stage Descriptive data (c) Consider use of a flow diagram * (a) Give characteristics of study participants (eg demographic, clinical, social) and information on exposures and potential confounders (b) Indicate number of participants with missing data for each variable of interest (c) Summarise follow-up time (eg, average and total amount) Outcome data * Report numbers of outcome events or summary measures over time Main results (a) Give unadjusted estimates and, if applicable, confounder-adjusted estimates and their precision (eg, % confidence interval). Make clear which confounders were adjusted for and why they were included (b) Report category boundaries when continuous variables were categorized (c) If relevant, consider translating estimates of relative risk into absolute risk for a meaningful time period Other analyses Report other analyses done eg analyses of subgroups and interactions, and sensitivity analyses n/a Discussion Key results Summarise key results with reference to study objectives Limitations Interpretation Give a cautious overall interpretation of results considering objectives, limitations, multiplicity of analyses, results from similar studies, and other relevant evidence Generalisability Discuss the generalisability (external validity) of the study results Other information Funding Give the source of funding and the role of the funders for the present study and, if applicable, for the original study on which the present article is based *Give information separately for cases and controls in case-control studies and, if applicable, for exposed and unexposed groups in cohort and cross-sectional studies. Note: An Explanation and Elaboration article discusses each checklist item and gives methodological background and published examples of transparent reporting. The STROBE checklist is best used in conjunction with this article (freely available on the Web sites of PLoS Medicine at Annals of Internal Medicine at and Epidemiology at Information on the STROBE Initiative is available at BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

4 Page of BMJ Open HTS for CF exacerbations // Pezzulo et al. Inhaled Hypertonic Saline In Adults Hospitalized For Exacerbation Of Cystic Fibrosis Lung Disease: A Retrospective Study Authors: Alejandro A. Pezzulo, M.D., alejandro-pezzulo@uiowa.edu David A. Stoltz, M.D./Ph.D., david-stoltz@uiowa.edu Douglas B. Hornick, M.D., douglas-hornick@uiowa.edu Lakshmi Durairaj, M.D. (Corresponding author, full address below) Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA,, USA Corresponding author: Lakshmi Durairaj University of Iowa, 0 EMRB, Iowa City, IA, Phone : +() Fax : +() lakshmi-durairaj@uiowa.edu This work was supported by the National Institutes of Health [Grants K HL0-, U0 HL-0 and K0 AI0] Key words: Cystic fibrosis, hypertonic saline, pulmonary exacerbation. Word count: - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

5 BMJ Open Page of HTS for CF exacerbations // Pezzulo et al. ABSTRACT : Background: Inhaled hypertonic saline (HTS) improves quality of life and reduces pulmonary exacerbations when given long term in patients with cystic fibrosis (CF). While increasingly being offered for acute pulmonary exacerbations, little is known about the efficacy in this setting. We examined the tolerability and efficacy of HTS use among adult subjects hospitalized with a CF pulmonary exacerbation and hypothesized that use of HTS would improve pulmonary function during the admission. Methods: We retrospectively examined subjects admitted to the inpatient service for acute CF pulmonary exacerbation in 0-0. In a subset of subjects who were also admitted in 0 when HTS was not available, we compared changes from baseline in FEV and weight, and time to next exacerbation after each of the visits. Results: Mean age was. years and mean length of stay was. days. HTS was offered to subjects and was well tolerated for a total use of days out of days of hospital stay. Baseline demographics, lung function and sputum culture results were comparable in both visits. Use of HTS was not associated with an improvement in FEV (p=0.), weight gain (p=0.) or in the time to next admission (p=0.0). Conclusion: These data suggest HTS is well tolerated during CF pulmonary exacerbation but offers no clear outcome benefits. It is possible that HTS may not have much advantage above and beyond intensive rehabilitation and intravenous antibiotics and may just add to hospital costs and treatment burden. - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

6 Page of BMJ Open HTS for CF exacerbations // Pezzulo et al. ARTICLE SUMMARY Article focus: Long-term use of inhaled hypertonic saline (HTS) improves pulmonary function and decreases exacerbation frequency in patients with cystic fibrosis (CF). Despite lack of available data regarding efficacy and safety, inhaled HTS is frequently used during hospitalization for exacerbation of CF pulmonary disease. Key messages: This study suggests that inhaled HTS is well tolerated during hospitalization for exacerbation of CF pulmonary disease. Short-term ( days) use of inhaled HTS provided no additional benefit over standard care (intravenous antibiotics and chest physical therapy) in pulmonary function, weight gain or time to next hospitalization. Strengths and limitations of this study: This study allowed intra-patient comparison of standard treatment with or without inhaled hypertonic saline in a relatively homogeneous adult population in an inpatient setting. The main limitation of this study is the retrospective design and unavailability of detailed noncompliance and side effect data. Sample size was adequate for the objectives of the study. - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

7 BMJ Open Page of HTS for CF exacerbations // Pezzulo et al. BACKGROUND: Lung disease is the leading cause of morbidity and mortality in patients with cystic fibrosis (CF). It is characterized by chronic bacterial colonization and recurrent infections of the airways, which have been evident manifestations of the disease since the term cystic fibrosis was first coined. [, ] Mutations in the cystic fibrosis transmembrane conductance regulator gene result in defective epithelial chloride transport in human airway epithelia, but the downstream consequences of this defect and how they result in CF lung disease remains to be further elucidated. [, ] The clinical course of patients with CF is characterized by periods of stable disease, interspersed by recurrent exacerbations during which symptoms such as sputum production and cough tend to acutely increase in intensity, and which are associated with increased bacterial density in the lungs and hypoxemia. [-] During acute CF lung disease exacerbation, usual treatment involves intravenous antibiotics, enhanced nutritional supplementation, and airway clearance therapies (e.g., frequent chest physiotherapy, inhaled albuterol, aerobic exercise). [, ] Inhaled hypertonic saline is an attractive addition because it is inexpensive, fairly well tolerated, and acutely increases whole-lung mucus clearance. Long-term treatment with inhaled hypertonic saline has been shown to improve pulmonary function and decrease exacerbation frequency. [-] To our knowledge, no studies have examined the role of inhaled hypertonic saline given during CF pulmonary exacerbation. In this retrospective study, we examine the impact of hypertonic saline use among a cohort of adult subjects hospitalized with CF pulmonary exacerbation and report its tolerability and efficacy compared to the same group of subjects in a previous - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

8 Page of BMJ Open HTS for CF exacerbations // Pezzulo et al. exacerbation during which hypertonic saline was not used. We hypothesized that use of inhaled hypertonic saline in addition to standard care during hospitalization for acute exacerbation of CF would result in greater improvement in usual endpoints such as pulmonary function, body weight and the time to next exacerbation when compared to standard of care. - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

9 BMJ Open Page of HTS for CF exacerbations // Pezzulo et al. METHODS: The study was approved by the University of Iowa Institutional Review Board (IRB# 0). This is a retrospective chart review of all adult admissions for CF lung disease exacerbation at the University of Iowa Hospitals and Clinics during the years 0 and 0 when inhaled hypertonic saline was offered to patients. Standard care consists of intravenous antibiotics chosen based on previous hospitalization sputum culture and susceptibility testing, and chest physical therapy times per day. Study subjects had a diagnosis of CF based on a sweat chloride test or a nasal voltage test, and genotyping of the CFTR gene. For the comparative study, data was abstracted from the admission during which hypertonic saline ( nd visit ) was used and compared to an earlier admission in the previous year (0) in which hypertonic saline was not used ( st visit ). Variables studied include age and gender, BMI on admission and discharge, duration of hospitalization, IV antibiotics use, CF mutation, use of chest physical therapy, sputum culture results, time to next exacerbation, and hypertonic saline use during subsequent hospitalizations. Baseline pulmonary function values were obtained from testing performed on admission day or in the previous days. During admission, pulmonary function testing was performed twice a week. One subject was discharged after days with a peripherally inserted central catheter to complete antibiotics at home. Subjects received an inhaled β agonist to minimize the risk of bronchospasm followed by a ml dose of % hypertonic saline solution twice daily through a Pari LC nebulizer. Compliance data is reported as total days of hypertonic saline use per total hospitalization days in the study population. For comparison study, only subjects who used hypertonic - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

10 Page of BMJ Open HTS for CF exacerbations // Pezzulo et al. saline at least days were included. Main outcome variable of comparison was change in % of predicted FEV from baseline to discharge. Subjects that failed to reach 0% of their best % of predicted FEV in the months previous to hospitalization were defined as non-responders to therapy. Other outcomes analyzed include length of stay, compliance, time to next admission, and weight gain. Power analysis suggested a sample size of patients to detect a change of % in FEV with SD of %, 0% power at two-tailed α of 0.0. Statistical Analysis: Data was analyzed using Prism for Mac OS (Graphpad Software, La Jolla, CA) and SAS version. (SAS Institute, Cary, North Carolina). Power analysis was performed using Statmate (Graphpad Software, La Jolla, CA). Univariate data is reported as means and standard deviation and proportions. Paired t-test was used for comparisons using a % level of significance. Mixed models for repeated measures were used to compare FEV change from baseline in the comparison study. Fisher s exact test was used to compute p-value of contingency analysis of non-responders and responders in both visits. - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

11 BMJ Open Page of HTS for CF exacerbations // Pezzulo et al. RESULTS: Study participants: Between January 0 and December 0, subjects were admitted to the CF inpatient service at the University of Iowa Hospitals and Clinics. Mean age at admission for this subject population was. ±. years and length of stay was. ±. days. % of these subjects were male. Of the subjects, were included in the comparative study as described in Methods. Baseline characteristics at admission for subjects that fulfilled inclusion criteria into the comparative study are shown in Table. During the study period, use of hypertonic saline at home prior to admission was uncommon (0% of subjects during the first visit and % during the second visit). - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

12 Page of BMJ Open HTS for CF exacerbations // Pezzulo et al. Table. Patient characteristics Characteristic st Visit nd Visit Age (yr). ±..0 ±. Male % - (n) () () BMI (kg/m ). ±.. ±. FEV (% of predicted). ±.. ±. FVC (L). ±.. ±. F0 homozygous % - (n) () () Inhaled tobramycin use % - (n) (). () HTS use at home % - (n) 0 (0) () Pancreatic insufficiency % - (n) () () Diabetes mellitus % - (n) () () Pseudomonas aeruginosa in sputum % - (n) () () Sputum density of Pseudomonas aeruginosa (Log CFU). ±.0.0 ±. Staphylococcus aureus % - (n) () () Length of stay (d).0 ±..0 ±. Table : Characteristics on admission for subjects included in comparative study. The admission (year 0) in which hypertonic saline was not used ( st visit) was compared to the admission (year 0 or 0) in which hypertonic saline was used ( nd visit). n =. Plus-minus values are mean ± SD. - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

13 BMJ Open Page of HTS for CF exacerbations // Pezzulo et al. Hypertonic saline is well tolerated by the majority of subjects hospitalized for acute exacerbation of cystic fibrosis During the study period, inhaled hypertonic saline was offered to out of subjects, of whom used it for at least day. The remaining subjects were not offered inhaled hypertonic saline due to history of asthma or recent hemoptysis. Among subjects, there was a collective use of hypertonic saline for a total of days out of days of hospitalization. Of the total discontinuation days, were explained by side effects (wheezing and mild hemoptysis) in subjects. Twenty-seven subjects used hypertonic saline for more than days. These data suggest that inhaled hypertonic saline is generally well tolerated by subjects hospitalized for exacerbation of cystic fibrosis lung disease. Hypertonic saline does not improve pulmonary function during hospitalization for acute exacerbation of cystic fibrosis Average change in percentage predicted FEV from baseline to discharge (in percentage points) was.% (% CI =..%) when hypertonic saline was not used and.% (% CI =..%) when hypertonic saline was used (Fig. A), suggesting that inhaled hypertonic saline resulted in decreased improvement in FEV at discharge (p = 0.0). However, the mean percentage predicted FEV at admission was higher when hypertonic saline was used (p = 0.0) (Fig. B) while the average discharge FEV values were not significantly different (p = 0.) between the two visits (Fig. C). The data suggest that the decrease in FEV improvement when inhaled hypertonic saline was used is therefore likely due to a higher admission FEV during that hospitalization. A mixed model adjustment for the differences in FEV at baseline showed no changes in FEV - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

14 Page of BMJ Open HTS for CF exacerbations // Pezzulo et al. improvement when inhaled hypertonic saline was used (p = 0.). Next, we analyzed the number of subjects that failed to reach at least 0% of their best % FEV in the months prior to admission. [] Four subjects were non-responders when hypertonic saline was not used and two when hypertonic saline was used (p = 0.). Overall, these data suggest that use of inhaled hypertonic saline during hospitalization for exacerbation of CF lung disease does not result in improved FEV over standard of care in this small population. Hypertonic saline does not augment weight gain during hospitalization for acute exacerbation of cystic fibrosis In our experience, subjects hospitalized for exacerbation of cystic fibrosis lung disease gain weight during the visit, probably as a result of enhanced caloric intake and/or control of the inflammatory state in the lungs resulting from infection. Figure shows that the addition of inhaled hypertonic saline was not associated with an improved weight gain during hospitalization. Average weight gain was.% (% CI = 0.. %) when hypertonic saline was not used and.% (% CI = -.. %) when hypertonic saline was used (p = 0.). Hypertonic saline does not increase time to next admission after an acute exacerbation of cystic fibrosis Since inhaled hypertonic saline was used during hospitalization but not as outpatient in our clinical practice through this study period and in the year 0, we were able to study the effect of inpatient hypertonic saline on time to next admission for pulmonary exacerbation. Figure shows that hypertonic saline was associated with decrease time to - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

15 BMJ Open Page of HTS for CF exacerbations // Pezzulo et al. next admission but this decrease is not statistically significant (p = 0.0). Average time to next admission was days when hypertonic saline was not used (% CI = 0 days) and days when hypertonic saline was used (% CI = days). Failure of increase in the time to next admission is probably related to short-term use of hypertonic saline in this study. - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

16 Page of BMJ Open HTS for CF exacerbations // Pezzulo et al. CONCLUSIONS: In this retrospective chart review of subjects hospitalized for exacerbation of CF lung disease, use of inhaled hypertonic saline was not associated with additional benefit over standard treatment, which includes intravenous antibiotics, enhanced nutritional supplementation and airway clearance therapies. Two recently published studies showed that inhaled hypertonic saline improved outcomes in CF subjects presumably by hydration of ASL and improved clearance of airway secretions. Hypertonic saline can improve pulmonary function and mucus clearance in patients with stable cystic fibrosis lung disease even when used for a short time ( weeks). [, ] In a large multi-center, randomized controlled trial of stable subjects with CF, twice daily inhalation of % hypertonic saline over weeks was shown to decrease exacerbation frequency compared to isotonic saline. [] The decrease in exacerbation frequency can also be observed in later stages of the disease. [] The only study of inpatient use of hypertonic saline to our knowledge is a study of hospitalized infants with viral bronchiolitis, where nebulized % hypertonic saline was well tolerated and reduced length of stay significantly. [] In another recent study, % hypertonic saline was found to be safe and well tolerated in infants with CF. [] Patients admitted for exacerbation of CF lung disease have been offered inhaled hypertonic saline as an adjunct to conventional therapy in our institution (and othersverbal communication). The decision to use inhaled hypertonic saline is based on the premise that the benefit will outweigh the risk of adverse events (which have been minimal in most studies), and the low cost and ease of administration of this agent. [,, -, -] However, inhaled hypertonic saline can induce cough [, -,, - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

17 BMJ Open Page of HTS for CF exacerbations // Pezzulo et al.,, ] in human subjects and has been used to provoke bronchoconstriction. [, ] In previous studies of inhaled hypertonic saline for cystic fibrosis, cough and dyspnea have been reasons for discontinuation of use and exclusion from study. [,,, ] Increased airway inflammation could cause hospitalized patients to be particularly susceptible to hypertonic saline induced bronchospasm. One of the primary aims of this study was to examine the safety and tolerability of hypertonic saline in this high-risk population. We did not observe an increased incidence of bronchospasm or worsening obstructive physiology when hypertonic saline was used. A recent analysis of risk factors that are associated with failure to recover to spirometric baseline (at least 0% of the best FEV in the months previous to an exacerbation) after intravenous antibiotic treatment reported that approximately % of subjects fail to recover at least months after the episode. [] In our study, out of of subjects failed to recover to spirometric baseline at discharge when hypertonic saline was not used whereas out of failed to do so when hypertonic saline was used. This analysis also fails to demonstrate significant benefit of using hypertonic saline during acute exacerbation of CF, although the data from both studies are not directly comparable, since patient populations with different characteristics are analyzed. Why were we unable to detect any improvement in pulmonary function tests or weight gain in this group of CF inpatients? In contrast to previous studies,[, ] this group of subjects do not present with stable lung disease. In a patient with acute exacerbation who is already receiving maximal treatment including IV antibiotics, chest physical therapy and rhdnase, the additional benefit of hypertonic saline could be trivial because of a ceiling effect. The fact that admission FEV during the visit in which - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

18 Page of BMJ Open HTS for CF exacerbations // Pezzulo et al. hypertonic saline was used was generally higher while discharge FEV was similar in both visits also supports a possible ceiling effect, in which only a certain degree of improvement may be possible, even with maximal therapy. Limitations of this study include retrospective nature of data collection from a single institution and unavailability of detailed noncompliance and side effects. Power analysis reveals that our sample size and data distribution allow us to detect a difference of at least.% FEV between admission and discharge FEV with 0% power. The sample size is too small to allow subgroup analysis based on factors such as baseline FEV and age. The absence of increased weight gain from using hypertonic saline during hospitalization could be the result of insufficient follow up time, although a long-term study also failed to demonstrate a benefit. [] This study also highlights an important clinical dilemma in CF patient care. In the last decade at least five new agents have shown benefits compared to placebo. [] These valuable placebo-controlled randomized control trials for new treatments however do not analyze synergy or interaction with other therapies. In real world applications, the clinician must apply new therapy in conjunction with standard treatments (e.g., airway clearance techniques) and other relatively new therapies (e.g., rhdnase). Questions such as How should the clinician prioritize these therapies? and Are there important interactions between these therapies? have been raised by those writing consensus documents for CF practice. [] The results of the current study demonstrate the importance of addressing these questions in well planned clinical trials since the outcomes of uncontrolled combinations in clinical practice are unpredictable. - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

19 BMJ Open Page of HTS for CF exacerbations // Pezzulo et al. In conclusion, in this study, use of inhaled hypertonic saline during hospitalization for acute exacerbation of CF was not associated with FEV improvement, additional weight gain, or increased time to next admission over standard treatment, which should cause clinicians to reconsider offering this treatment to patients hospitalized for an exacerbation of CF and as well as consider withholding this treatment during exacerbations in patients who already receive it in an outpatient basis until well controlled therapeutic combination type studies can show added efficacy. As new therapies are expected, the CF community will increasingly face the dilemma of how to combine/prioritize multiple effective treatments. - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

20 Page of BMJ Open HTS for CF exacerbations // Pezzulo et al. COMPETING INTEREST: Authors declare no conflicts of interest - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

21 BMJ Open Page of HTS for CF exacerbations // Pezzulo et al. AUTHORS CONTRIBUTIONS AP, DS, DH, and LD: contributed to the overall concept, design and interpretation of the study, data collection and manuscript preparation. All authors read and approved the final manuscript. LD guarantees the accuracy of data presented in this study. - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

22 Page of BMJ Open HTS for CF exacerbations // Pezzulo et al. ACKNOWLEDGMENTS: This work was supported by the National Institutes of Health [Durairaj K HL0- and U0 HL-0 and Stoltz K0 AI0]. Funding sources had no role in study design, manuscript writing or decision to publish. The authors would like to thank Drs. Joseph Zabner and Michael Welsh for insightful discussion, Dr. Bridget Zimmerman for guiding our statistical analyses, and Janice Launspach for excellent assistance. - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

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24 Page of BMJ Open HTS for CF exacerbations // Pezzulo et al. Elkins MR, Bye PT. Inhaled hypertonic saline as a therapy for cystic fibrosis. Curr Opin Pulm Med 0;:-. Elkins MR, Robinson M, Rose BR, et al. A controlled trial of long-term inhaled hypertonic saline in patients with cystic fibrosis. N Engl J Med 0;:-0. Ratjen F. Inhaled hypertonic saline produces small increases in lung function in patients with cystic fibrosis. J Pediatr 0;:. Subbarao P, Balkovec S, Solomon M, et al. Pilot study of safety and tolerability of inhaled hypertonic saline in infants with cystic fibrosis. Pediatr Pulmonol 0;:-. Suri R, Grieve R, Normand C, et al. Effects of hypertonic saline, alternate day and daily rhdnase on healthcare use, costs and outcomes in children with cystic fibrosis. Thorax 0;:-. Suri R, Marshall LJ, Wallis C, et al. Effects of recombinant human DNase and hypertonic saline on airway inflammation in children with cystic fibrosis. Am J Respir Crit Care Med 0;:-. Suri R, Metcalfe C, Lees B, et al. Comparison of hypertonic saline and alternateday or daily recombinant human deoxyribonuclease in children with cystic fibrosis: a randomised trial. Lancet 0;:-. Taylor LM, Kuhn RJ. Hypertonic saline treatment of cystic fibrosis. Ann Pharmacother 0;:-. Sanders DB, Bittner RC, Rosenfeld M, et al. Failure to recover to baseline pulmonary function after cystic fibrosis pulmonary exacerbation. Am J Respir Crit Care Med ;: BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

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27 BMJ Open Page of HTS for CF exacerbations // Pezzulo et al. Figure Legends Figure : Forced expiratory volume in second. The admission (year 0) in which hypertonic saline was not used (-) was compared to the admission (year 0 or 0) in which hypertonic saline was used (+). (A) Change from admission to discharge forced expiratory volume in second. Units are change in total percentage of predicted. Mean ± % confidence interval are shown. (B and C) Percent predicted forced expiratory volume in second at admission (B) or discharge (C). Units are percentage of predicted. Lines join data from both visits for the same subject. n =. *=p 0.0. ns=p>0.0. Figure : Change from baseline weight. The admission (year 0) in which hypertonic saline was not used (-) was compared to the admission (year 0 or 0) in which hypertonic saline was used (+). Units are percent change in weight from admission to discharge. n =. Data = mean ± % confidence interval. Figure : Time to next admission. The admission (year 0) in which hypertonic saline was not used (-) was compared to the admission (year 0 or 0) in which hypertonic saline was used (+). Units are number of days between discharge and next admission with a diagnosis of acute exacerbation of CF lung disease. n =. Data = mean ± % confidence interval. - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

28 Page of BMJ Open Forced expiratory volume in second. The admission (year 0) in which hypertonic saline was not used (- ) was compared to the admission (year 0 or 0) in which hypertonic saline was used (+). (A) Change from admission to discharge forced expiratory volume in second. Units are change in total percentage of predicted. Mean ± % confidence interval are shown. (B and C) Percent predicted forced expiratory volume in second at admission (B) or discharge (C). Units are percentage of predicted. Lines join data from both visits for the same subject. n =. *=p 0.0. ns=p>0.0. 0xmm (00 x 00 DPI) - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

29 BMJ Open Page of Change from baseline weight. The admission (year 0) in which hypertonic saline was not used (-) was compared to the admission (year 0 or 0) in which hypertonic saline was used (+). Units are percent change in weight from admission to discharge. n =. Data = mean ± % confidence interval. xmm (00 x 00 DPI) - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

30 Page of BMJ Open Time to next admission. The admission (year 0) in which hypertonic saline was not used (-) was compared to the admission (year 0 or 0) in which hypertonic saline was used (+). Units are number of days between discharge and next admission with a diagnosis of acute exacerbation of CF lung disease. n =. Data = mean ± % confidence interval. x0mm (00 x 00 DPI) - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

31 BMJ Open Inhaled Hypertonic Saline In Adults Hospitalized For Exacerbation Of Cystic Fibrosis Lung Disease: A Retrospective Study Journal: BMJ Open Manuscript ID: bmjopen r Article Type: Research Date Submitted by the Author: -Feb- Complete List of Authors: Pezzulo, Alejandro; University of Iowa, Internal Medicine Stoltz, David; University of Iowa, Internal Medicine Hornick, Douglas; University of Iowa, Internal Medicine Durairaj, Lakshmi; University of Iowa, Internal Medicine <b>primary Subject Heading</b>: Drugs and medicines Secondary Subject Heading: Respiratory medicine Keywords: Cystic fibrosis < THORACIC MEDICINE, THERAPEUTICS, Respiratory infections < THORACIC MEDICINE BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright. -

32 Page of BMJ Open 0 0 Section/Topic Item # STROBE 0 (v) Statement Checklist of items that should be included in reports of cohort studies Recommendation Reported on page # Title and abstract (a) Indicate the study s design with a commonly used term in the title or the abstract Introduction (b) Provide in the abstract an informative and balanced summary of what was done and what was found Background/rationale Explain the scientific background and rationale for the investigation being reported Objectives State specific objectives, including any prespecified hypotheses Methods Study design Present key elements of study design early in the paper Setting Describe the setting, locations, and relevant dates, including periods of recruitment, exposure, follow-up, and data collection Participants (a) Give the eligibility criteria, and the sources and methods of selection of participants. Describe methods of follow-up (b) For matched studies, give matching criteria and number of exposed and unexposed Variables Clearly define all outcomes, exposures, predictors, potential confounders, and effect modifiers. Give diagnostic criteria, if Data sources/ measurement applicable * For each variable of interest, give sources of data and details of methods of assessment (measurement). Describe comparability of assessment methods if there is more than one group Bias Describe any efforts to address potential sources of bias - Study size Explain how the study size was arrived at Quantitative variables Explain how quantitative variables were handled in the analyses. If applicable, describe which groupings were chosen and why Statistical methods (a) Describe all statistical methods, including those used to control for confounding Results on January by guest. Protected by copyright. (b) Describe any methods used to examine subgroups and interactions (c) Explain how missing data were addressed (d) If applicable, explain how loss to follow-up was addressed (e) Describe any sensitivity analyses - BMJ Open: first published as./bmjopen on April. Downloaded from - -

33 BMJ Open Page of 0 0 Participants * (a) Report numbers of individuals at each stage of study eg numbers potentially eligible, examined for eligibility, confirmed eligible, included in the study, completing follow-up, and analysed (b) Give reasons for non-participation at each stage Descriptive data (c) Consider use of a flow diagram * (a) Give characteristics of study participants (eg demographic, clinical, social) and information on exposures and potential confounders (b) Indicate number of participants with missing data for each variable of interest (c) Summarise follow-up time (eg, average and total amount) Outcome data * Report numbers of outcome events or summary measures over time Main results (a) Give unadjusted estimates and, if applicable, confounder-adjusted estimates and their precision (eg, % confidence interval). Make clear which confounders were adjusted for and why they were included (b) Report category boundaries when continuous variables were categorized (c) If relevant, consider translating estimates of relative risk into absolute risk for a meaningful time period Other analyses Report other analyses done eg analyses of subgroups and interactions, and sensitivity analyses n/a Discussion Key results Summarise key results with reference to study objectives Limitations Interpretation Give a cautious overall interpretation of results considering objectives, limitations, multiplicity of analyses, results from similar studies, and other relevant evidence Generalisability Discuss the generalisability (external validity) of the study results Other information Funding Give the source of funding and the role of the funders for the present study and, if applicable, for the original study on which the present article is based *Give information separately for cases and controls in case-control studies and, if applicable, for exposed and unexposed groups in cohort and cross-sectional studies. Note: An Explanation and Elaboration article discusses each checklist item and gives methodological background and published examples of transparent reporting. The STROBE checklist is best used in conjunction with this article (freely available on the Web sites of PLoS Medicine at Annals of Internal Medicine at and Epidemiology at Information on the STROBE Initiative is available at BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

34 Page of BMJ Open HTS for CF exacerbations // Pezzulo et al. Inhaled Hypertonic Saline In Adults Hospitalized For Exacerbation Of Cystic Fibrosis Lung Disease: A Retrospective Study Authors: Alejandro A. Pezzulo, M.D., alejandro-pezzulo@uiowa.edu David A. Stoltz, M.D./Ph.D., david-stoltz@uiowa.edu Douglas B. Hornick, M.D., douglas-hornick@uiowa.edu Lakshmi Durairaj, M.D. (Corresponding author, full address below) Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA,, USA Corresponding author: Lakshmi Durairaj University of Iowa, 0 EMRB, Iowa City, IA, Phone : +() Fax : +() lakshmi-durairaj@uiowa.edu This work was supported by the National Institutes of Health [Grants K HL0-, U0 HL-0 and K0 AI0] Key words: Cystic fibrosis, hypertonic saline, pulmonary exacerbation. Word count: - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

35 BMJ Open Page of HTS for CF exacerbations // Pezzulo et al. ABSTRACT : Background: Inhaled hypertonic saline (HTS) improves quality of life and reduces pulmonary exacerbations when given long term in patients with cystic fibrosis (CF). While increasingly being offered for acute pulmonary exacerbations, little is known about the efficacy in this setting. We examined the tolerability and efficacy of HTS use among adult subjects hospitalized with a CF pulmonary exacerbation and hypothesized that use of HTS would improve pulmonary function during the admission. Methods: We retrospectively examined subjects admitted to the inpatient service for acute CF pulmonary exacerbation in 0-0. In a subset of subjects who were also admitted in 0 when HTS was not available, we compared changes from baseline in FEV and weight, and time to next exacerbation after each of the visits. Results: Mean age was. years and mean length of stay was. days. HTS was offered to subjects and was well tolerated for a total use of days out of days of hospital stay. Baseline demographics, lung function and sputum culture results were comparable in both visits. Use of HTS was not associated with an improvement in FEV (p=0.), weight gain (p=0.) or in the time to next admission (p=0.0). Conclusion: This pilot data suggest HTS is well tolerated during CF pulmonary exacerbation but offers no clear outcome benefits. It is possible that HTS may not have much advantage above and beyond intensive rehabilitation and intravenous antibiotics and may just add to hospital costs and treatment burden. - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

36 Page of BMJ Open HTS for CF exacerbations // Pezzulo et al. ARTICLE SUMMARY Article focus: Long-term use of inhaled hypertonic saline (HTS) improves pulmonary function and decreases exacerbation frequency in patients with cystic fibrosis (CF). Despite lack of available data regarding efficacy and safety, inhaled HTS is frequently used during hospitalization for exacerbation of CF pulmonary disease. Key messages: This retrospective non-randomized study suggests that inhaled HTS is well tolerated during hospitalization for exacerbation of CF pulmonary disease. Short-term ( days) use of inhaled HTS provided no added improvement over standard care (intravenous antibiotics and chest physical therapy) in pulmonary function, weight gain or time to next hospitalization. Strengths and limitations of this study: This study allowed within-patient comparison of standard treatment with or without inhaled hypertonic saline in a relatively homogeneous adult population in an inpatient setting. The main limitation of this study is the retrospective and non-randomized design and unavailability of detailed compliance and side effect data. Sample size was adequate for the objectives of the study. - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.

37 BMJ Open Page of HTS for CF exacerbations // Pezzulo et al. BACKGROUND: Lung disease is the leading cause of morbidity and mortality in patients with cystic fibrosis (CF). It is characterized by chronic bacterial colonization and recurrent infections of the airways, which have been evident manifestations of the disease since the term cystic fibrosis was first coined.[, ] Mutations in the cystic fibrosis transmembrane conductance regulator gene result in defective epithelial chloride transport in human airway epithelia, but the downstream consequences of this defect and how they result in CF lung disease remains to be further elucidated.[, ] The clinical course of patients with CF is characterized by periods of stable disease, interspersed by recurrent exacerbations during which symptoms such as sputum production and cough tend to acutely increase in intensity, and which are associated with increased bacterial density in the lungs and hypoxemia.[-] During acute CF lung disease exacerbation, usual treatment involves intravenous antibiotics, enhanced nutritional supplementation, and airway clearance therapies (e.g., frequent chest physiotherapy, inhaled albuterol, aerobic exercise).[, ] Inhaled rhdnase can improve pulmonary function when used long term, albeit at a relatively high cost.[- ] Inhaled hypertonic saline is an attractive addition because it is inexpensive, fairly well tolerated, and acutely increases whole-lung mucus clearance. Long-term treatment with inhaled hypertonic saline has been shown to improve pulmonary function and decrease exacerbation frequency.[-] However, hypertonic saline use during an exacerbation may be potentially more harmful by causing more bronchospasm or hemoptysis. To our knowledge, no studies have examined the safety profile and efficacy of inhaled hypertonic saline treatment given during CF pulmonary exacerbation. - BMJ Open: first published as./bmjopen on April. Downloaded from on January by guest. Protected by copyright.