Questions are frequently raised regarding aggressive

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1 Late Outcomes of Open Heart Surgery in Patients 70 Years or Older Jamal H. Khan, MD, Sandra Magnetti, DrPH, Elaine Davis, EdD, and Jianliang Zhang, PhD Charleston Area Medical Center, West Virginia University, Charleston, West Virginia Background. The purpose of this study is to examine the long-term survival and quality of life, including the influence of comorbidities, in patients 70 years of age and over after open heart surgery. Methods. This was a retrospective study of 401 consecutive patients, who were 70 years of age or older at the time of surgery. Survival and quality of life of these patients were measured at 6- to 8-year follow-up. Results. The 5-year survival rate was 85%, and was comparable with the age- and gender-matched West Virginia population. Survival declined with increasing preexisting comorbidities. Of the 176 respondents completing the quality of life (SF-36) survey, most scores were similar to or substantially better than the US population normative scores for individuals 70 years of age or older. Conclusions. Survival rates vary by presence or absence of specific comorbid conditions. Quality of life in the appropriately selected elderly after open heart surgery appears to be similar to the US population normative scores. (Ann Thorac Surg 2000;69:165 70) 2000 by The Society of Thoracic Surgeons Questions are frequently raised regarding aggressive surgical management of the elderly with heart disease, particularly those suffering from other comorbid conditions [1]. Many publications have shown the relative safety and short-term benefits of heart surgery in the elderly [2 8]. Little is known about longer-term outcomes, including the influence of other concurrent diseases on quality of life in these patients. The number of elderly individuals having open heart surgery is increasing [9, 13]. Thus, there is a critical need to evaluate long-term survival and quality of life outcomes in elderly heart disease patients in order to justify expensive treatment modalities in an increasingly restrictive managed care environment. The purpose of this study was to examine the long-term survival and quality of life in patients 70 years of age and over after open heart surgery. Material and Methods Basic Characteristics of the Study Group A cohort of 401 consecutive patients 70 years of age or older at the time of their surgery during the years of 1987 and 1988 was retrospectively identified using a computerized clinical database of a cardiac surgical group in a large medical center. The short 2-year surgical cohort time also minimized bias from improving technology. The data collected at baseline, before surgery, included demographics, type of surgery (coronary artery bypass graft only, valve only, or combination), status at surgery Accepted for publication June 30, Address reprint requests to Dr Khan, Suite 411, MSOB, 3100 MacCorkle Ave, Charleston, WV (elective, urgent, or emergent), laboratory values, such as creatinine, and clinical comorbidities. The comorbid conditions studied included chronic obstructive pulmonary disease (COPD), diabetes mellitus, congestive heart failure (CHF), cerebral vascular disease, and chronic renal insufficiency (CRF). COPD was defined as patients requiring specific treatment for COPD or requiring pulmonary consultation. Thus, only advanced cases of COPD were included. Diabetes included both insulin and noninsulin-dependent diabetics. CHF included both compensated and noncompensated CHF. Cerebrovascular disease included patients with a history of transient ischemic attacks (TIA), cerebral vascular accidents (CVA), known carotid disease, and carotid bruits. Chronic renal insufficiency (CRF) was diagnosed if preoperative serum creatinine was 1.5 or greater. Open heart surgery was considered elective if the patient was admitted electively for surgery, urgent if the patient was unstable or had critical disease precluding discharge from the hospital before surgery, and emergent if the patient had to be moved to surgery immediately upon surgical evaluation. Hospital mortality was defined as death during the same hospitalization or within 30 days of surgery. Follow-up was completed in 1995, 6 to 8 years after surgery. Survival status was confirmed by telephone contact with the patient or a relative. Hospital and office records as well as records from the patients primary physicians were also used to determine the survival status of the patients. State mortality records were used to confirm deaths. Surviving patients were administered a Quality of Life questionnaire, the SF-36 [10], over the telephone, 7 to by The Society of Thoracic Surgeons /00/$20.00 Published by Elsevier Science Inc PII S (99)

2 166 KHAN ET AL Ann Thorac Surg LATE OUTCOMES OF HEART SURGERY IN THE ELDERLY 2000;69: years postsurgery, during 1995 by a trained nurse. The SF-36 was selected for its validity and reliability and its extensive use in other chronic disease assessments, as well as in general population surveys [10]. The SF-36 consists of eight scales. The content of each scale is listed in the Appendix. The possible range of the SF-36 scale score is 0 to 100, 0 being the lowest possible score. The scoring algorithms as suggested by its developers (Ware and associates, 1993 [10]) were used, which permits comparison with published general US population norms. Data Analysis Survival rates of the cohort were obtained using confirmed deaths from time of discharge to end of the study in 1996 (survival rates did not include hospital mortality, which was defined as death during the same hospital admission or within 30 days of treatment). These rates were compared with the age- and gender-matched population derived from West Virginia life tables [11]. For each subject of a particular age and gender, the probability of survival for 1, 2, or more years was determined from the US Decennial Life Tables for 1989 to 1991 for West Virginia. Because the expected value of a Bernoulli random variable is equal to its parameter, in this case the probability of survival, the sum of the probabilities of 1, 2, or more years of survival, is equal to the expected number of survivors in an age- and gender-matched group selected from the state at large. The Cox proportional hazards 2 was used to examine the effect of age on survival. The effects of the number of comorbidities on survival were evaluated using Kaplan-Meier methods. The log-rank test was used to assess significance. We also determined differences in survival of groups formed by the presence or absence of pertinent comorbidities such as diabetes, COPD, and CHF as compared with patients with no recorded comorbidities. Analysis of variance was used to evaluate the effect of comorbidities on quality of life. The statistical software used was JMP (version 3.2.2; SAS Institute, Cary, NC) [12]. Results Characteristics of the Study Population The mean age of all patients (n 401) was 74.5 years at the time of surgery (standard deviation 3.4, range 70 to 93 years). Fifty percent of the patients were between 70 and 75 years, 45% between 75 and 80 years, and 5% between 80 and 93 years of age. Males represented 58.9% of the study population. Overall, 82% had coronary artery bypass grafting (CABG) only. Only 8.2% had valve surgery and 9.8% had a combined procedure. Regarding urgency of operation, 38.2% were considered elective, 48.1% urgent, and 13.7% emergent. The most prevalent comorbidity was diabetes. Prevalence of other comorbidities is listed in Table 1. The hospital mortality rate for the entire group was 5.4%, leaving 379 survivors for follow-up. A comparison of patient demographics for age, type of surgery, and Table 1. Characteristics at Admission for Study Population Admission Study Population Discharged Alive SF-36 Respondents N Average age (y) SD 3.1 Gender % Male 58.9 (236) 59.9 (227) 64.2 (113) % Female 41.1 (165) 40.1 (152) 35.8 (63) Comorbidities [% (n)] Diabetes mellitus 23.2 (93) 23.5 (89) 16.0 (28) Severe COPD 13.2 (53) 13.2 (50) 10.3 (18) CHF 15.5 (62) 14.5 (55) 8.6 (15) CVD 2.2 (9) 2.4 (9) 7.2 (9) Renal insufficiency 20.7 (83) 20.6 (77) 14.0 (25) (Creatinine 1.5) Type of surgery (%) CABG 82.0 (327) 83.3 (315) 85.1 (149) Valve only 8.3 (33) 7.9 (30) 6.3 (11) Combination 9.8 (39) 8.7 (33) 9.1 (16) Status of surgery (%) Elective 38.2 (153) 38.9 (147) 41.1 (72) Urgent 48.1 (193) 48.1 (183) 44.0 (76) Emergent 13.7 (55) 13.0 (49) 14.9 (26) Characteristics at admission for total heart surgery population, the patients who were discharged alive, or within 30 days of discharge, and the patients who responded to the SF-36 at 5 to 8 years postop. CABG coronary artery bypass graft; CHF congestive heart failure; COPD chronic obstructive pulmonary disease; CVD cerebrovascular disease. status of surgery showed no difference between those who died and those who survived to the end of follow-up. The exception was for gender, where the percentage of females who responded was lower than that of the males ( p 0.003) (Table 1). Survival Follow-up was complete in 98.1% of the patients. The overall 5-year actuarial survival was 85%. The Kaplan- Meier actuarial probability of survival for 379 patients who survived surgery was compared with the age- and gender-matched state population from West Virginia Life Tables 1989 to 1991 [11]. There was no significant difference in the 1- to 7-year probabilities of survival between the West Virginia general population and the surgical population (goodness of fit test, Pearson 2 NS) (Fig 1). Differences in the survival curves by gender, type of surgery, and status of the operation were not significant (log rank test NS). Age at surgery was significantly related to survival, with a 4% to 5% decrease in survival for each year increase in age at surgery ( p 0.05, proportional hazards, 2 ). Effect of Comorbidities on Survival Kaplan-Meier survival curves indicate a decreased survival with increasing number of comorbidities (log rank test p ) (Fig 2). The mean survival time for

3 Ann Thorac Surg KHAN ET AL 2000;69: LATE OUTCOMES OF HEART SURGERY IN THE ELDERLY 167 Fig 1. The Kaplan-Meier actuarial probability of survival for the 379 patients who survived the hospitalization after cardiac surgery was compared with the age- and gender-matched state population from the West Virginia Life Table 1989 to Goodness of fit test, Pearson 2 NS). patients with no comorbidities was 6 years. With one comorbidity, survival fell to an average of 5.3 years, and with three comorbidities, it was 4.9 years. The 5-year survival of the patients with no comorbidities was 82.97%. For those with one comorbidity, it was 66.41%, and those with more than one comorbidity, 55.97%. Examination of survival curves for single specific preexisting comorbidities (diabetes, CHF, renal insufficiency, and COPD) show they have similar survival rates (log rank test NS) (Fig 3). Quality of Life There were 237 patients alive at follow-up in One hundred and seventy-six responded to the survey. The response rate was 74%. Forty-eight patients could not be contacted, and 5 were unable to answer the questions due to diseases such as dementia. There were no refusals. Fig 2. Kaplan-Meier survival curves indicate decreased survival with increasing number of comorbidities (log-rank test p 0.001). Fig 3. Survival time of patients with preexisting comorbidities. There was no significant difference between responders and nonresponders based on age, type and number of comorbidities, type of surgery, or status at surgery. However, males had a higher response rate than females ( p 0.003). The SF-36 scores were similar to or substantially higher than those for a sample of the age- and gender-matched US population. The exception to this trend was for the Mental Health score, which was significantly lower than that of the US population ( p 0.001) (Fig 4). An analysis of the impact of the presence or absence of different comorbidities on quality of life was performed by examining the mean SF-36 scores for patients with various combinations of comorbidities that were present in this patient population. The Mental Health score was significantly lower for the combinations of comorbidities that were present ( p ). Not all combinations of the three diseases (diabetes, COPD, and CHF) could be analyzed because the sample sizes were too small (Table 2). Comment The purpose of this study was to examine the long-term survival and quality of life outcomes, and the impact of comorbidities in a retrospective cohort of open heart surgery patients at least 70 years of age at the time of surgery. In this population, the 5-year survival was 85%, which was comparable with or higher than other similar studies [14, 15]. Most notable was the fact that the 5- to 8-year survival after open heart surgery was not significantly different from a hypothetical age- and gendermatched West Virginia population for the same time period. This observation is supported by survival studies, such as Canver and associates, who also compared their study population with the age-matched population derived from Wisconsin life tables [14, 15]. As shown in other studies [16], survival time declined in groups with increasing preexisting comorbidities such as diabetes, COPD, and renal insufficiency. Not all comorbidities in the patient population of this study, such

4 168 KHAN ET AL Ann Thorac Surg LATE OUTCOMES OF HEART SURGERY IN THE ELDERLY 2000;69: Fig 4. Quality of Life (SF-36) mean scores of surgery patients compared with norms for SF-36 scales in the general US population 70 years of age. **p value significant at level. as cerebrovascular disease, could be evaluated for significance in the survival analyses because of small numbers. The effect of peripheral vascular disease could not be studied because of the lack of reliable documentation. Quality of life for the West Virginia open heart surgery patients as measured by the eight Quality of Life scores of the SF-36 was found to be similar to US population norms [10]. Other studies have attempted to measure improvements in quality of life [4, 5], but the SF-36 is one of the first QOL instruments to have published national gender- and age-adjusted normative values [10]. The findings from the SF-36 portion of this study help to support the evidence of a return to normal functioning for elderly patients who have survived heart surgery as compared with those of similar age and gender in the general US population. The only SF-36 score that came out lower than the national norms was that of mental health. This observation may be explained by accounts in the literature [17] that have shown depression to be associated with cardiovascular disease. This factor is not well understood, as it may have been a preexisting condition associated with cardiovascular disease or be a factor that is not affected by open heart surgery. Several studies mention preoperative depression in heart patients [17]. Comorbidities affect survival and quality of life after surgery [18, 19]. This study shows that long-term outcomes of survival and quality of life decrease as the number of comorbidities increases. Specific comorbidities in this patient population such as diabetes, COPD, or CHF are associated with lower SF-36 scores. This observation is supported by a previous study by Stewart and associates [20], who reported that comorbidities in patients with chronic conditions had a significant effect on quality of life as measured by the SF-36 in the Medical Outcomes Study (MOS) in approximately 2,706 patients, including those with diabetes and congestive heart failure. Number of comorbidities may have an effect on decision making as to whether surgery is an effective alternative. Although open heart surgery, in this study, produced good outcomes in both survival and quality of life, we should emphasize the influence of preexisting comorbidities on the overall outcome. The main limitation with this study is that it is a retrospective study. Consequently, the SF-36 was only given at follow-up. We compared our population with national norms for quality of life and state survival rates for survival. Ideally, we would want to have an appropriate comparison cohort at baseline in addition to following patients prospectively. There is a paucity of long-term survival and quality of Table 2. Analysis of the Impact of Different Comorbid Combinations on Quality of Life a CHF Diabetes a COPD a Mean SF-36 Scores PF RP BP GH VT SF RE MH b b b b b Not all patients had combinations of all comorbidities. a 1 present; 0 absent. b p value significant at p BP bodily pain; CHF congestive heart failure; COPD chronic obstructive pulmonary disease; GH general health; MH mental health; PF physical functioning; RE role-emotional; RP role-physical; SF social functioning; VT vitality.

5 Ann Thorac Surg KHAN ET AL 2000;69: LATE OUTCOMES OF HEART SURGERY IN THE ELDERLY 169 life outcomes data on the elderly population undergoing heart surgery. There is frequent criticism of an aggressive surgical approach to the management of heart disease in the elderly by some [1]. This study contributes to the continued comprehensive research on the long-term outcomes of cardiovascular surgery: survival and quality of life in addition to measuring the impact of comorbidities. Surgery is a reasonable choice in appropriately selected elderly heart disease patients, and it is most reasonable in those with the fewest comorbidities. We are grateful to Anne Matthews, CCRN, for doing the follow-up interviews, Gerry Hobbs, PhD, for his statistical advice, Joe Fuller, MS, and Don Hanshew, MA, for their data management, and Alan Ducatman, MD, and Syed Islam, MD, for their editorial assistance in preparation of the manuscript. References 1. Iskandrian AS, Segal BL. Should cardiac surgery be performed in octogenarians? J Am Coll Cardiol 1991;18: Freeman WK, Schaff HV, O Brien P, Orszulak TA, Naessens JM, Tajik AJ. Cardiac surgery in the octogenarian: perioperative outcome and clinical follow-up. J Am Coll Cardiol 1991; 18: Krumholz HM, Forman DE, Kuntz RE, Baim DS, Wei JY. Coronary revascularization after myocardial infarction in the very elderly: outcomes and long-term follow-up. Ann Intern Med 1993;119: Soderlind K, Rutberg H, Olin C. Late outcome and quality of life after complicated heart operations. Ann Thorac Surg 1997;63: Chocron S, Etievent JP, Viel JF, et al. Prospective study of quality of life before and after open heart operations. Ann Thorac Surg 1996;61: Steine S, Laerum E, Eritsland J, Arnesen H. Predictors of enhanced well-being after coronary artery bypass surgery. J Intern Med 1996;239: Sjolind H, Wiklund I, Caidahl K, Haglid M, Westberg S, Herlitz J. Improvement in quality of life and exercise capacity after coronary bypass surgery. Arch Intern Med 1996;156: Page SA, Verheof MJ, Emes CG. Quality of life, bypass surgery and the elderly. Can J Cardiol 1995;11: Tsai TP, Denton TA, Chaux A, Matloff JM, Kass RM, Blanche C, Khan SS. Results of coronary artery bypass grafting and/or aortic or mitral valve operation in patients 90 years of age. Am J Cardiol 1994;74: Ware JE. Scoring the SF-36. In: Ware JE, Snow KK, Kosinski M, Gandek B. SF-36 Health Survey Manual and Interpretation Guide. Boston: The Health Institute, New England Medical Center, 1993;6: US Decennial Life Tables for , State Life Tables for West Virginia, Vol II (49). Hyattsville, MD: CDC/NCHS, USDHH, JMP, version Cary, NC: SAS Institute, Peterson ED, Cowper PA, Jollis JG, et al. Outcomes of coronary artery bypass graft surgery in 24,461 patients aged 80 years or older. Circulation 1995;92(Suppl 9): Canver CC, Nichols RD, Cooler SD, Heisey DM, Murray EL, Kroncke GM. Influence of increasing age on long-term survival after coronary artery bypass grafting. Ann Thorac Surg 1996;62: Ruygrok PN, Agnew TM, Coverdale HA, Kerr AR, Graham KJ, Whitlock RM. Coronary artery surgery in the elderly: long-term follow-up. Aust New Zealand J Med 1993;23: Deiwick M, Tandler R, Mollhoff T, et al. Heart surgery in patients aged eighty years and above: determinants of morbidity and mortality. Thorac Cardiovasc Surg 1997;45: Glassman AH, Shapiro PA. Depression and the course of coronary artery disease. Am J Psychiatry 1998;155: Carey JS, Cukingnan RA, Singer LK. Quality of life after myocardial revascularization. Effect of increasing age. J Thorac Cardiovasc Surg 1992;103: Sjoland H, Caidahl K, Wiklund I, et al. Impact of coronary artery bypass grafting on various aspects of quality of life. Eur J Cardiothorac Surg 1997;12: Stewart AL, Greenfield S, Hays RD, et al. Functional status and well-being of patients with chronic conditions. Results from the Medical Outcomes Study. JAMA 1989;262: Appendix Content of Questions by Type of Scale for SF-36 Scale Item a Abbreviated Content Physical functioning (PF) 3a Vigorous activities, such as running, lifting heavy objects, strenuous sports 3b Moderate activities, such as moving a table, vacuuming, bowling 3c Lifting or carrying groceries 3d Climbing several flights of stairs 3e Climing one flight of stairs 3f Bending, kneeling, or stooping 3g Walking more than a mile 3h Walking several blocks 3i Walking one block 3j Bathing or dressing Role-physical (RP) 4a Limited in the kind of work or other activities 4b Cut down the amount of time spent on work or other activities 4c Accomplished less than would like 4d Difficulty performing the work or other activities Bodily pain (BP) 7 Intensity of bodily pain 8 Extent pain interfered with normal work

6 170 KHAN ET AL Ann Thorac Surg LATE OUTCOMES OF HEART SURGERY IN THE ELDERLY 2000;69: Continued Scale Item a Abbreviated Content General health (GH) 1 Is your health: excellent, very good, good, fair, poor 11a My health is excellent 11b I am as healthy as anybody I know 11c I seem to get sick a little easier than other people 11d I expect my health to get worse Physical functioning (PF) Vitality (VT) 9a Feel full of pep 9e Have a lot of energy 9g Feel worn out 9i Feel tired Social functioning (SF) 6 Extent health problems interfered with normal social activities 10 Frequency health problems interfered with social activities Role-emotional (RE) 5a Cut down the amount of time spent on work or other activities 5b Accomplished less than would like 5c Didn t do work or other activities as carefully as usual Mental health (MH) 9b Been a very nervous person 9c Felt so down in the dumps nothing could cheer you up 9d Felt calm and peaceful 9f Felt downhearted and blue 9h Been a happy person a Actual number of item on survey.