A Study of Patient Experience Using a Blood Glucose Meter With an In-Built Insulin Dose Calculator

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1 532489DSTXXX / Journal of Diabetes Science and TechnologyRamtoola et al research-article2014 Original Article A Study of Patient Experience Using a Blood Glucose Meter With an In-Built Insulin Dose Calculator Journal of Diabetes Science and Technology 2014, Vol. 8(4) Diabetes Technology Society Reprints and permissions: sagepub.com/journalspermissions.nav DOI: / dst.sagepub.com Shenaz Ramtoola, MD 1, Edward Jude, MD 2, Anthony Robinson, DM 3, Iqbal Malik, MD 4, Gerrard Rayman, MD 5, Cuong Dang, MD 6, Graham David RossMartin, MB ChB 7, and Amar Ali, MB ChB 1 Abstract Background: Accurate calculation and adjustment of insulin doses is integral to maintaining glycemic control in insulin treated patients. Difficulties with insulin dose calculations may lead to poor adherence to blood glucose monitoring and insulin treatment regimes, resulting in poor metabolic control. The main objective of this study was to evaluate ease of use and user preference of a high specification touch screen blood glucose meter, which has an in-built insulin calculator, compared to patients usual method of testing blood glucose and deciding insulin doses. Methods: Patients with diabetes on a multiple daily injection insulin regime used the Test Meter without the insulin calculator and 1 of 3 comparator meters, each for a 7-day period. They then used the Test Meter with the in-built calculator for 10 days. Patients completed an ease of use questionnaire after each 7-day period, a preference questionnaire after the second 7-day period, and a questionnaire comparing the Test Meter with their usual method after the final 10-day period. Results: Of 164 patients who completed the study, 76% stated a preference for the Test Meter as a diabetes management tool compared to their usual method. A small number of patients preferred familiar methods and/or calculating insulin doses themselves. The log book function of meters was important to most patients. Conclusions: The Test Meter system with in-built insulin calculator supports people to better manage their diabetes and increases their confidence. Patients have different needs and preferences which should be acknowledged and supported in a patient centered health service. Keywords blood glucose meter, bolus calculator, diabetes, insulin Patient self-management through blood glucose monitoring and accurate calculation and adjustment of insulin doses is integral to glycemic control in patients with insulin treated diabetes. This is a challenge for many patients as multiple variables need to be considered. There is evidence in adolescents suggesting that poor compliance with insulin regimes due to a lack of understanding of and/or frustration with the complexity of insulin dose calculations may contribute to poor metabolic control. 1 A recent study of patients with type 2 diabetes (T2D) showed that many lack the understanding and skills to apply selfmonitoring data to aid therapy adjustments. 2 High avoidance (avoiding thinking about blood glucose values and diabetes) and a sense of pointlessness of self-monitoring were associated with infrequent self-monitoring and use of self-monitoring data for insulin dose adjustments, and lack of sharing data with health care professionals. The authors suggested that if patients were guided in seeing the value of self-monitoring blood glucose it could improve adherence to self-monitoring. A blood glucose meter (BGM) which is easy to use with features to assist patients with dose calculations may promote increased frequency of glucose testing and improved diabetes self-management. The FreeStyle InsuLinx BGM 1 Royal Blackburn Hospital, Blackburn, UK 2 Tameside Hospital NHS Foundation Trust, Ashton-under-Lyne, UK 3 Royal United Hospital, Bath, UK 4 Ayr Hospital, Ayr, UK 5 Ipswich Hospital, Ipswich, UK 6 University of Salford Diabetes Centre, North Manchester General Hospital, Manchester, UK 7 Greenwood Medical Centre, Nottingham, UK Corresponding Author: Shenaz Ramtoola, MD, Consultant Physician, Royal Blackburn Hospital, Haslingden Road, Blackburn, BB2 3HH, UK. Shenaz.Ramtoola@elht.nhs.uk

2 Ramtoola et al 777 Group 1 Comparator BGM InsuLinx BG Mode only InsuLinx with Insulin Calculator (10 days) Group 2 InsuLinx BG Mode only Comparator BGM Day User Questionnaire #1 User Questionnaire #2 & Preference Questionnaire Preference Questionnaire InsuLinx v Usual Method Figure 1. Study design. contains an in-built bolus insulin dose calculator. Insulin, medication doses, food intake, physical activity, and health information can be logged. In easy mode the meter suggests the insulin dose based on a usual prescribed meal dose, current and target glucose levels. In advanced mode carbohydrate intake and insulin-to-carbohydrate ratios are also taken into account. The main objective of this study was to evaluate ease of use and user preference of this meter compared to patients usual method of testing blood glucose and deciding insulin doses. A secondary objective was to compare the ease of use of the meter with other leading BGMs. Patients and Methods This was a randomized, 2-arm, cross-over study conducted at 7 sites in the United Kingdom from September 2011 to April The clinical protocol Ease of Use of New BGM with In-Built Insulin Calculator at Home Study (ADC-PMS- INX-11011) was approved by the National Research Ethics Committee. The study was registered on ClinicalTrials.gov (NCT ). Study Participants Eligible patients were adults with type 1 diabetes (T1D) or T2D on a multiple daily injection (MDI) insulin regime (insulin adjusting) for at least 6 months, regularly doing 3 or more blood glucose tests per day, and willing to do at least 4 tests daily, who had no previous experience of the FreeStyle InsuLinx meter (Abbott Diabetes Care, Alameda, CA; Test Meter) or the assigned comparator meter. All patients gave written informed consent. Study Design and Plan Patients used the Test Meter without the insulin calculator (BG mode) and 1 of 3 assigned comparator BGMs (Accu- Chek Aviva Nano [Roche Diagnostics, Mannheim, Germany; Comparator 1], Bayer Contour USB [Bayer Consumer Care, Basel, Switzerland; Comparator 2], LifeScan Verio Pro [LifeScan Europe, Zug, Switzerland: Comparator 3]) each for a 7-day period (Figure 1). They completed an ease of use questionnaire after each 7-day period for the BGM used, and after the second 7-day period a preference questionnaire comparing the 2 BGMs used. They then used the Test Meter with the in-built insulin dose calculator (IC mode) for 10 days, after which they completed a 2-part questionnaire, part A comparing the Test Meter with their usual method of testing blood glucose and calculating insulin dose, and part B evaluating specific features of the Test Meter. Patients were randomized into 1 of 2 groups, to use either the Test Meter or comparator BGM first. A 1-hour training session was given to patients on use of the Test Meter in BG Mode and the comparator BGM, supported by use of a structured training checklist for each meter. A half-hour training session on use of the Test Meter in IC mode was given after completing the first 14 days of the study. Easy mode setup was used in patients using a pattern-based insulin regime. Advanced mode setup was used for patients

3 778 Journal of Diabetes Science and Technology 8(4) Table 1. Baseline Characteristics of Patients (n = 164). Characteristic 7 (4.3) Male sex 83 (50.6) Caucasian 161 (98.2) Completed college education 74 (45.1) BMI (31.1) T1D 128 (78.0) Experienced severe hypoglycemia 8 (4.9) episodes in last 6 months Experienced severe hyperglycemia episodes in last 6 months a Carbohydrate counting 82 (50) who used a carbohydrate-counting based insulin regime. No changes were made to patients usual insulin regimes. Statistical Analysis The exact binomial test for proportion was performed to determine the statistical significance of the inequality in preference, or inequality in agreement and disagreement with ease of use statements, in those patients stating a preference or an opinion. All analyses were conducted using SAS version Results Mean ± SD (range) 4.3 ± 1.9 (2-20) Age (years) 48.8 ± 13.0 (19-82) BMI (kg/m 2 ) 28.1 ± 5.5 ( ) Years since diagnosis 21 ± 13 (1-58) Number of blood glucose tests daily b HbA1c (%) b 8.8 ± 1.4 ( ) a Severe hyperglycemia was defined as a hyperglycemic event requiring attention from medical personnel and/or hospitalization. b n = 162 and 158, respectively. A total of 178 eligible adult patients were enrolled, of whom 164 completed the study. Baseline characteristics of these patients are shown in Table 1. Ease of use questionnaires showed that most patients found all 4 study meters with their test strips easy to use and gave them information on how they were doing with their blood glucose. A significant majority of patients also considered that the Test Meter and Comparators 2 and 3 gave them information on how they were doing with managing their diabetes as well as how they needed to manage their blood glucose (Table 2). The results of the preference questionnaire between the 2 meters used by each patient are shown in Table 3. The Test Meter was significantly favored over Comparator 1. There was no significant difference in patient preference between the Test Meter and Comparators 2 and 3. The meters were rated as about the same in questions on individual aspects of use by 23-73% of patients. Among patients who expressed a preference in these questions, the Test Meter was significantly favored over Comparator 1 for all responses except for the number of error messages, and over Comparator 3 for easier set up of date, time and language, and for wasting fewer strips. Altogether 133 patients (81%) said they would definitely or probably change their meter for a study meter; 98 patients (60%) would definitely or probably change for the Test Meter. Table 4 shows the meter features other than testing blood glucose levels indicated by patients to be important to them. The log book was by far the most valued feature. Table 5 shows patients evaluation of specific features of the Test Meter. Most patients considered that the touch screen was easy to use; the system helped them decide their insulin dose and feel more confident about it and about managing their diabetes. Table 6 shows the results of the questionnaire comparing the Test Meter as a diabetes management tool compared to the patients usual method of testing blood glucose and calculating insulin dose. There was a significant preference for the Test Meter over patients usual method (76% vs 17%, P <.0001). Over 70% of patients considered the Test Meter was a better system to manage their diabetes, gave them the information they need to help manage their diabetes, made them feel more confident when adjusting their mealtime insulin and about managing their diabetes, and was more helpful and easier to decide and log an insulin dose. Among the 125 patients expressing a preference for the Test Meter, the commonest reason cited in the free text section of the questionnaire related to the insulin calculator function (n = 55, 44%), followed by overall and specific aspects of ease of use (n = 40, 32%), and log book and other information functions (n = 26, 21%). Conversely, among the 27 patients who preferred their usual method, the most common cited reason (n = 9, 33%) also related to the insulin calculator, such as ability or preference to calculate own insulin doses or use prescribed doses, lack of trust in or inability to adapt to the insulin calculator, and self-reported hypoglycemia after taking the insulin dose recommended by the Test Meter. Four (15%) patients expressed not liking change, preferring or feeling more comfortable with usual routine. Two patients had an episode of severe hypoglycemia during the study; 1 of these was assessed as not related to study device met serious adverse event (SAE) criteria; the other was assessed as possibly related to the study device. Both patients were using the Test Meter. Another patient reported an increased frequency of hypoglycemia throughout the study, during use of both Comparator Meter and Test Meter, in BG or IC mode.

4 Ramtoola et al 779 Table 2. Responses From Ease of Use Questionnaires About Study Meters. Statement Meter a Yes No P value yes vs no The meter is easy to use Comparator 1 54 (91.5) 5 (8.5) <.0001 Comparator 2 50 (96.2) 2 (3.8) <.0001 Comparator 3 51 (98.1) 1 (1.9) <.0001 Test Meter 153 (93.9) 10 (6.1) <.0001 The strips are easy to use with this meter Comparator 1 49 (83.1) 9 (15.3) <.0001 Comparator 2 48 (92.3) 4 (7.7) <.0001 Comparator 3 45 (86.5) 7 (13.5) <.0001 Test Meter 148 (90.8) 15 (9.2) <.0001 The meter gives me information on how I am doing with my blood glucose The meter gives me information on how I am doing with managing my diabetes The meter gives me information on how I need to manage my blood glucose Comparator 1 47 (79.7) 12 (20.3) <.0001 Comparator 2 48 (92.3) 4 (7.7) <.0001 Comparator 3 44 (84.6) 8 (15.4) <.0001 Test Meter 149 (91.4) 14 (8.6) <.0001 Comparator 1 36 (61.0) 22 (37.3) ns Comparator 2 43 (82.7) 9 (17.3) <.0001 Comparator 3 36 (69.2) 15 (28.8) <.01 Test Meter 125 (76.7) 38 (23.3) <.0001 Comparator 1 35 (59.3) 24 (40.7) ns Comparator 2 34 (65.4) 18 (34.6) <.05 Comparator 3 33 (63.5) 17 (32.7) <.05 Test Meter 120 (73.6) 41 (25.2) <.0001 a Comparator 1 n = 59; Comparator 2 n = 52; Comparator 3 n = 52; Test Meter n = 163. Comparison meter ease of use questionnaire for 1 patient was lost, this patient excluded from above analysis. Where results do not add to 100% it is due to missing answers for that response. Discussion The main objective of the study was to evaluate the user preference and ease of use of a meter with an in-built insulin dose calculator, compared to patients usual method of testing blood glucose and deciding insulin doses, when used by patients on a MDI insulin regime. Of patients, 76% stated a preference for using the Test Meter system as a diabetes management tool over their usual method. Over 70% of patients felt more confident adjusting their insulin and managing their diabetes, and over 90% considered the system easy to use, and gave them information on how they were doing with their blood glucose. The fact that patients found the system helped in the interpretation of blood glucose test results and in using these to decide an insulin dose could help overcome the feelings of avoidance and pointlessness identified as obstacles to blood glucose self-monitoring. 2 A previous study showed that using the bolus calculator built into the Test Meter minimized errors in insulin dose determination. 4 Glaser et al observed a higher frequency of errors with conventional bolus calculation methods compared with an insulin dose calculation device. 1 They suggested that consistent use of the insulin dose calculation device may help to improve metabolic control. Maurizi et al demonstrated that using an insulin dose calculator did improve HbA1c levels in T1D patients compared to manual calculation. 5 A recent review on the use of BGMs with builtin bolus calculators concluded that these are effective motivational tools which empower the patient through an increased capability to translate self-monitored blood glucose values into appropriate therapeutic decisions. 6 A small proportion of patients, however, prefer familiar routines, calculating their own or using prescribed insulin doses; this must be acknowledged and supported. Potential risks of hypoglycemia in any automated system must also be borne in mind, and appropriate patient education in this respect is important. In recent years much progress has been made in BGM technology, which now provides an array of features additional to blood glucose testing. This study gave further insight into patients views on such additional features. The log book feature was overwhelmingly the additional feature most valued by patients. Among patients who stated a preference for the Test Meter over their current method, the calculator function, ease of use and log book and other information functions were the most frequent cited reasons for their preference. Budget constraints in many health care systems have resulted in restrictions on meter and test strip availability and choice, cost considerations being paramount irrespective of additional features. This study demonstrates patients

5 780 Journal of Diabetes Science and Technology 8(4) Table 3. Responses to the Preference Questionnaire Test Meter vs Comparator Meter. Question Response Which meter... Assigned comparator meter a Test Meter About the same Comparator meter P value Test Meter vs comparator meter Is easiest to setup date, time and Comparator 1 22 (37.3) 30 (50.8) 2 (3.4) <.0001 language? Comparator 2 9 (17.0) 33 (62.3) 9 (17.0) ns Comparator 3 10 (19.2) 38 (73.1) 2 (3.8) <.05 Is easier to test blood glucose with? Comparator 1 28 (47.5) 26 (44.1) 3 (5.1) <.0001 Comparator 2 14 (26.4) 22 (41.5) 16 (30.2) ns Comparator 3 13 (25.0) 25 (48.1) 14 (26.9) ns Is easier to use for blood glucose Comparator 1 34 (57.6) 19 (32.2) 4 (6.8) <.0001 monitoring? Comparator 2 18 (34.0) 17 (32.1) 18 (34.0) ns Comparator 3 17 (32.7) 23 (44.2) 12 (23.1) ns Gave fewer error messages? Comparator 1 14 (23.7) 32 (54.2) 9 (15.3) ns Comparator 2 9 (17.0) 30 (56.6) 5 (9.4) ns Comparator 3 15 (28.8) 25 (48.1) 7 (13.5) ns Did you waste fewer test strips Comparator 1 24 (40.7) 25 (42.4) 6 (10.2) <.01 with? Comparator 2 17 (32.1) 20 (37.7) 9 (17.0) ns Comparator 3 20 (38.5) 18 (34.6) 8 (15.4) <.05 Is easiest to use? Comparator 1 29 (49.2) 24 (40.7) 6 (10.2) Comparator 2 17 (32.1) 18 (34.0) 17 (32.1) ns Comparator 3 21 (40.4) 15 (28.8) 16 (30.8) ns Is the most user friendly? Comparator 1 37 (62.7) 16 (27.1) 5 (8.5) <.0001 Comparator 2 22 (41.5) 12 (22.6) 19 (35.8) ns Comparator 3 20 (38.5) 16 (30.8) 16 (30.8) ns Makes your life simpler? Comparator 1 32 (54.2) 21 (35.6) 5 (8.5) <.0001 Comparator 2 20 (37.7) 19 (35.8) 14 (26.4) ns Comparator 3 16 (30.8) 26 (50.0) 10 (19.2) ns Gives you the information you Comparator 1 36 (61.0) 20 (33.9) 3 (5.1) <.0001 need to help manage your Comparator 2 17 (32.1) 28 (52.8) 8 (15.1) ns diabetes? Comparator 3 15 (28.8) 29 (55.8) 8 (15.4) ns Is a better blood glucose Comparator 1 40 (67.8) 16 (27.1) 3 (5.1) <.0001 monitoring system to help you Comparator 2 20 (37.7) 20 (37.7) 13 (24.5) ns manage your diabetes? Comparator 3 18 (34.6) 24 (46.2) 10 (19.2) ns Do you prefer? Comparator 1 45 (76.3) 8 (13.6) 6 (10.2) <.0001 Comparator 2 26 (49.1) 5 (9.4) 22 (41.5) ns Comparator 3 25 (48.1) 6 (11.5) 19 (36.5) ns a Comparator 1 n = 59; Comparator 2 n = 53; Comparator 3 n = 52. Where results do not add to 100% it is due to missing answers for that response. different needs and preferences in respect of blood glucose monitoring, which should be acknowledged in any patient centered health care service. Clinicians should be supported to meet these individual needs and preferences, and thus promote patient collaboration, involvement and empowerment in managing their diabetes.

6 Ramtoola et al 781 Table 4. Blood Glucose Meter Features Important to Patients. What meter features are important to you? Log book 140 (85.4) Reports 75 (45.7) Alarms 42 (25.6) Upload software 42 (25.6) Weekly messages 34 (20.7) Personalization 25 (15.2) Other 17 (10.4) No answer 7 (4.3) Total number of patients = 164. Table 5. Patients Evaluation of Specific Features of the Test Meter. Statement Conclusion Response The Test Meter... Yes No N/A Gives me helpful information if an error occurs Auto-assist information was useful Active insulin feature was helpful Has a touch screen that is easy to use Helps you decide how much insulin to take Helps you feel confident about how much mealtime insulin to take Gives information that makes you feel more confident in managing your diabetes P value yes vs no 60 (36.6) 7 (4.3) 97 (59.1) < (47.0) 8 (4.9) 78 (47.6) < (54.9) 13 (7.9) 61 (37.2) < (90.9) 14 (8.5) N/A < (92.1) 13 (7.9) N/A < (91.5) 14 (8.5) N/A < (91.5) 14 (8.5) N/A <.0001 Total number of patients = 164. Where results do not add to 100% it is due to missing answers for that response. Over 70% of patients on a MDI insulin regime preferred the Test Meter, a BGM system with in-built insulin calculator, over their usual method of testing blood glucose and deciding insulin doses. They found it easy to use and felt more confident adjusting their mealtime insulin dose and managing their diabetes. This study has highlighted that patients have different preferences. Greater flexibility should be allowed by health care systems in supporting patients choices. Abbreviations BGM, blood glucose meter; MDI, multiple daily injection; SAE, serious adverse event; T1D, type 1 diabetes; T2D, type 2 diabetes. Table 6. Comparison of Test Meter to Patients Usual Method. Question Response Usual method P value test meter vs usual method Which method... Test Meter About the same Is a better system to 131 (79.9) 19 (11.6) 14 (8.5) <.0001 manage your diabetes? Gives you the information 137 (83.5) 20 (12.2) 7 (4.3) <.0001 you need to help manage your diabetes? Makes you feel more 122 (74.4) 29 (17.7) 13 (7.9) <.0001 confident about managing your diabetes? Is easier to use when 107 (65.2) 35 (21.3) 22 (13.4) <.0001 managing your diabetes? Is more helpful when 135 (82.3) 16 (9.8) 13 (7.9) <.0001 deciding your insulin dose? Is easier to decide an 132 (80.5) 21 (12.8) 11 (6.7) <.0001 insulin dose? Makes you feel more 119 (72.6) 27 (16.5) 18 (11.0) <.0001 confident when adjusting your mealtime insulin? Gave you fewer errors in 98 (59.8) 46 (28.0) 13 (7.9) <.0001 your insulin dose? Is easier to log an insulin 148 (90.2) 6 (3.7) 10 (6.1) <.0001 dose? Makes your life more 103 (62.8) 38 (23.2) 23 (14.0) <.0001 simple? Did you prefer? 125 (76.2) 12 (7.3) 27 (16.5) <.0001 Total number of patients = 164. Where results do not add to 100% it is due to missing answers for that response. Acknowledgments We thank the following for assistance: Study personnel at the 7 clinical sites for execution of this study; Walter Amor and Zoe Welsh (Abbott Diabetes Care) for assistance with statistical analysis. Declaration of Conflicting Interests The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: The trial was designed by Abbott Diabetes Care with input from the chief investigator. FreeStyle and related brand marks are trademarks of Abbott Diabetes Care Inc in various jurisdictions. Funding The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was sponsored by Abbott Diabetes Care Ltd. References 1. Glaser NS, Iden SB, Green-Burgeson D, et al. Benefits of an insulin dosage calculation device for adolescents with type 1 diabetes mellitus. J Pediatr Endocrinol Metab. 2004;17(12):

7 782 Journal of Diabetes Science and Technology 8(4) 2. Polonsky WH, Fisher L, Hessler D, Edelman SV. What is so tough about self-monitoring of blood glucose? Perceived obstacles among patients with type 2 diabetes. Diabetes Med. 2014;31(1): SAS Institute Inc. SAS/STAT 9.2 User s Guide. Cary, NC: SAS Institute Inc; Sussman A, Taylor EJ, Patel M, Ward J, Alva S, Lawrence A, Ng R. Performance of a glucose meter with a built-in automated bolus calculator versus manual bolus calculation in insulin-using subjects. J Diabetes Sci Technol. 2012;6(2): Maurizi AR, Lauria A, Maggi D, et al. A novel insulin unit calculator for the management of type 1 diabetes. Diabetes Technol Ther. 2011;13(4): Colin IM, Paris I. Glucose meters with built-in automated bolus calculator: gadget or real value for insulin-treated diabetic patients? Diabetes Ther. 2013;4(1):1-11.