Relationship between quality of life and exercise test findings after coronary artery bypass surgery

Predictors of Quality of Life Improvement after 2 Years of Coronary Artery Bypass Surgery

PURPOSE

The aim was to examine the predictors of improvement of quality of life after 2 years of coronary artery bypass grafting (CABG).

METHODS

In all, 208 patients who underwent the elective CABG at the Institute for Cardiovascular Diseases Dedinje in Belgrade were contacted and examined 2 years after the surgery. All patients completed Nottingham Health Profile Questionnaire part one.

RESULTS

Two years after CABG, quality of life (QOL) in patients was significantly improved in all sections compared to preoperative period. Independent predictors of QOL improvement after 2 years of CABG were found to be serious angina under sections of physical mobility [p = 0.003, odds ratio (OR) = 1.76, 95% confidence interval (CI) 1.21-2.55], energy (p = 0.01, OR = 1.63, 95% CI: 1.11-2.38), sleep (p = 0.005, OR = 1.65, 95% CI: 1.16-2.35), pain (p <0.001, OR = 2.43, 95% CI: 1.57-3.77), absence of hereditary load in energy section (p = 0.002, OR = 0.35, 95% CI: 0.18-0.68), male sex in the sleep section (p = 0.03, OR = 0.43, 95% CI: 0.20-0.93), and absence of diabetes in pain section (p = 0.006, OR = 0.27, 95% CI: 0.10-0.68).

CONCLUSION

Predictors of improvement of QOL after 2 years of CABG are serious angina, absence of hereditary load, male sex, and absence of diabetes.

Functional Recovery and Exercise Behavior in Men and Women 5 to 6 Years Following Coronary Artery Bypass Graft (CABG) Surgery

Improvement following coronary artery bypass graft (CABG) surgery has been reported to be less in women than men. Relationships between exercise behavior and functional status of men and women 5 to 6 years after CABG have not been examined in a representative patient sample. This study compared the 5- to 6-year recovery in a cohort of 184 patients at the Minnesota site of the Post CABG Biobehavioral Study. Data were collected by telephone interviewand self-administered questionnaires. Results showed that women had lower physical ( p ≤ .004) and social ( p = .001) functioning scores; men were more likely to participate in regular exercise ( p = .01). Exercisers had higher functional status scores. ANCOVA demonstrated that differences in measures of functional status by exercise category were maintained even after controlling for age, sex, and symptom severity ( p ≤ .01). In conclusion, individuals who exercised had more positive functional outcomes 5 to 6 years post-CABG.

A prospective, interventional assessment of psoriasis quality of life using a nonskin-specific validated instrument that allows comparison with other major medical conditions

BACKGROUND

Psoriasis significantly impacts patients' quality of life.

OBJECTIVES

The purpose of this study was to prospectively assess the quality-of-life impact of treatment for moderate to severe plaque psoriasis by using a validated quality-of-life psychometric instrument that has been widely used in nondermatologic settings.

METHODS

In all, 32 patients with moderate to severe plaque psoriasis received 24 weeks of adalimumab treatment. Patients completed the Psychological General Well-Being (PGWB) Index, which evaluates 6 domains including anxiety and depression. The primary end point was the change in total PGWB score at weeks 12 and 24 of adalimumab treatment compared with baseline.

RESULTS

Statistically significant improvement in the total PGWB score was documented by week 4. By week 24, all 6 PGWB domains showed statistically significant improvement from the pretreatment baseline.

LIMITATIONS

One limitation of this study is that the comparison between our psoriasis data and PGWB data from other major medical conditions was not conducted in a head-to-head manner. Another limitation is that we did not have a controlled (placebo) arm.

CONCLUSION

Based on PGWB scores, patients with untreated psoriasis have as much impairment in psychological well-being as patients with other major medical diseases including breast cancer, coronary artery disease, congestive heart failure, and diabetes and that potent intervention improves psychological well-being to where it is comparable with that of patients with asymptomatic hypertension. A prompt intervention with an effective dermatologic treatment is not only critical, but capable of restoring the physical and psychological well-being of patients with psoriasis.

Self-efficacy and health status in patients with coronary heart disease: findings from the heart and soul study

OBJECTIVE

To examine the relationship between cardiac self-efficacy and health status, including symptom burden, physical limitation, quality of life, and overall health among outpatients with stable coronary heart disease (CHD). We hypothesized that lower self-efficacy would predict worse health status, independent of CHD severity and depression.

METHODS

We performed a cross-sectional study of 1024 outpatients with CHD, who were recruited between 2000 and 2002 for the Heart and Soul Study. We administered a validated measure of cardiac self-efficacy, assessed cardiac function using exercise treadmill testing with stress echocardiography, and measured depressive symptoms using the Patient Health Questionnaire. Health status outcomes (symptom burden, physical limitation, and quality of life) were assessed using the Seattle Angina Questionnaire, and overall health was measured as fair or poor (versus good, very good, or excellent).

RESULTS

After adjustment for CHD severity and depressive symptoms, each standard deviation (4.5-point) decrease in self-efficacy score was independently associated with greater symptom burden (adjusted odds ratio (OR) = 2.1, p = .001), greater physical limitation (OR = 1.8, p < .0001), worse quality of life (OR = 1.6, p < .0001), and worse overall health (OR = 1.9, p < .0001). Depressive symptoms and poor treadmill exercise capacity were also associated with poor health status, but left ventricular ejection fraction and ischemia were not.

CONCLUSIONS

Among patients with CHD, low cardiac self-efficacy is associated with poor health status, independent of CHD severity and depressive symptoms. Further study should examine if self-efficacy constitutes a useful target for cardiovascular disease management interventions.

Time trends of chest pain symptoms and health related quality of life in coronary artery disease

BACKGROUND

There is at present a lack of knowledge of time trends in health related quality of life (HRQL) in common patients with coronary artery disease (CAD) treated in ordinary care. The objective of this study is to assess and compare time trends of health related quality of life (HRQL) and chest pain in patients with coronary artery disease.

METHODS

253 consecutive CAD patients in Stockholm County, Sweden--197 males/56 females; 60 +/- 8 years--were followed during two years. Perceived chest pain symptoms and three global assessments of HRQL were assessed at baseline, after one and after two years. EuroQol-5 dimension (EQ-5D) with a predefined focus on function and symptoms; the broader tapping global estimates of HRQL; EuroQol VAS (EQ-VAS) and Cardiac Health Profile (CHP) were used. Chest pain was ranked according to Canadian Cardiovascular Society (CCS). Change in HRQL was analysed by a repeated measurements ANOVA and chest pain symptoms were analysed by Friedman non-parametric ANOVA.

RESULTS

Perceived chest pain decreased during the two years (p < 0.00022); CCS 0: 41-51%; CCS 1: 19-15%; CCS 2: 31-27%; CCS 3: 5-4% and CCS 4: 4-2%. By contrast, HRQL did not change: EQ-5D: 0.76 (CI 0.73-0.79) -0.78 (CI 0.75-0.81), EQ-VAS: 0.68 (CI 0.66-0.71)-0.68 (CI 0.65-0.71) and CHP: 0.66 (CI 0.64-0.69) -0.66 (CI 0.64-0.69).

CONCLUSION

HRQL did not increase despite a reduction in the severity of chest pain during two years. This implies that the major part of HRQL in these consecutive ordinary patients with CAD is unresponsive to change in chest pain symptoms.

Severity of Angina as a Predictor of Quality of Life Changes Six Months After Coronary Artery Bypass Surgery

BACKGROUND

Although the fact that chest pain has a negative influence on the quality of life is well known, it is not completely clear whether the preoperative severity of angina can be a predictor of the quality of life change after coronary artery bypass grafting (CABG).

METHODS

We studied 243 consecutive patients who underwent elective CABG. The Nottingham Health Profile Questionnaire part 1 was used as the model for determination of quality of life. We distributed the questionnaire to all patients before and six months after coronary artery bypass surgery. Two hundred and twenty-six patients filled in the postoperative questionnaire. Severity of angina was estimated by Canadian Cardiovascular Society (CCS) classification of angina.

RESULTS

Quality of life (before and after CABG surgery) in all sections was significantly worse in patients with higher CCS angina class (p < 0.001). The CCS angina class was 1.89 +/- 0.97 at baseline and improved to 0.46 +/- 0.75 (p < 0.001) after CABG. Six months after the operation, quality of life significantly improved in patients with all classes of angina (p < 0.01). The improvement in quality of life was related to higher CCS angina class in sections of physical mobility (r = 0.4, p < 0.001), energy (r = 0.31, p < 0.001), and pain (r = 0.48, p < 0.001). High CCS angina class before CABG was an independent predictor of quality of life improvement after coronary artery bypass surgery in sections of physical mobility (p = 0.005; odds ratio [OR] = 2.11; confidence interval [CI] 1.25 to 3.55), energy (p = 0.021; OR = 1.77; CI 1.09 to 2.87), and pain (p < 0.001; OR = 3.99; CI 2.2 to 7.22).

CONCLUSIONS

Patients with higher CCS angina class had worse preoperative and postoperative quality of life. Patients with preoperative higher CCS angina class had greater improvement in sections of physical mobility, energy, and pain. High CCS angina class before CABG was the independent predictor of quality of life improvement six months after CABG.

Gastroesophageal reflux symptoms and well-being in a random sample of the general population of a Swedish community

OBJECTIVES

There is limited information on the relationship between gastroesophageal reflux symptoms and well-being in the general population. This study aimed to investigate this relationship and determine the severity threshold at which reflux symptoms meaningfully affect patients' well-being.

METHODS

A random sample of the population of Malmö, Sweden (n = 4,624), was sent the Gastrointestinal Symptom Rating Scale, the Subjective Symptom Assessment Profile, and the Psychological General Well-Being Index. The relationship between well-being and the severity of heartburn, acid regurgitation, stomach pain, and abdominal pain was investigated by analysis of covariance (ANCOVA).

RESULTS

Complete data were obtained from 1,476 subjects (43% male; mean age [standard deviation], 49.9 [14.2] yr). The mean Psychological General Well-Being Index score was 102 (95% CI: 101-103). Increasing symptom severity was associated with a decrease in well-being, and correlations between Psychological General Well-Being Index score and symptom severity ratings were statistically significant. At least mild symptoms of heartburn or abdominal pain (a mean Gastrointestinal Symptom Rating Scale score of > or =3) were associated with a clinically meaningful reduction in well-being (a Psychological General Well-Being Index score of less than 98).

CONCLUSIONS

Reflux symptoms are associated with impaired well-being in the general population. Individuals with symptoms that are mild or more severe report a meaningful reduction in well-being similar to that seen in other diseases. This may represent an appropriate threshold for patient selection in trials of GERD therapy and for more detailed evaluation of patients consulting with reflux symptoms in clinical practice.

Perceived cognitive function is a major determinant of health related quality of life in a non-selected population of patients with coronary artery disease ? a principal components analysis

OBJECTIVE

To assess health related quality of life (HRQL) and explore its underlying structure in a non-selected population of patients with coronary artery disease (CAD).

DESIGN, SETTING AND SUBJECTS

HRQL was estimated by the disease specific Cardiac Health Profile (CHP) questionnaire and the EuroQol-VAS (EQ) in 253 consecutive unselected CAD patients in Södertälje, Stockholm County, Sweden. Explorative factor analysis was used to identify independent dimensions of HRQL. Current angina was ranked according to Canadian Cardiovascular Society Classification (CCS).

RESULTS

Four independent principal factors representing perceived cognitive, physical, social and emotional functions underlying the patients' HRQL were found. Identical factors were recognized with an alternate technique. The major factor--explaining 43 % of HRQL--was perceived cognitive function reflecting ability to concentrate, activity drive, memory and problem solving. Cognitive function correlated to EQ but not to CCS. Perceived physical function/general health explained 9% of HRQL and was as expected related both to EQ and CCS. Total CHP scores differed significantly to those of healthy controls.

CONCLUSIONS

Perceived cognitive function seems to be a major determinant of HRQL in CAD patients. This, in addition to earlier reports of possible prognostic information of reduced cognitive function, would prompt us to propose that HRQL assessments should include questions aimed to assess cognitive function.

Relationships between self-reported health related quality of life and measures of standardized exercise capacity and metabolic efficiency in a middle-aged and aged healthy population

BACKGROUND

The purpose of this study was to evaluate to what extent self-reported health related quality of life (HRQL), assessed by the Swedish standard version of the Medical Outcome Study Short-Form 36 (SF-36), is related to measured exercise capacity and metabolic efficiency in a cohort of healthy subjects from the Gothenburg area of Sweden.

MATERIAL AND METHODS

Individuals were invited to take part in the evaluation where HRQL was compared with the maximal power output expressed in Watts assessed during a standardized treadmill test with incremental work loads. Whole body respiratory gas exchanges (CO2/O2) were simultaneously measured. Estimate of metabolic efficiency was derived from oxygen uptake per Watt produced (ml O2/min/W) near maximal work.

RESULTS

The health status profile in the current population largely agreed with normative data from an age- and gender-matched reference group, although some measured scores were slightly better than reference scores. Males and females had a similar relationship between energy cost (ml O2/min) for production of maximal work (W), while the regressions for maximal exercise power and age were significantly different between males and females (p < 0.01). The overall metabolic efficiency was the same in individuals between 40 and 74 years of age (10.4 +/- 0.07 ml O2/min/ Watt). Maximal exercise power was only related to the SF-36 subscale physical functioning (PF), but unrelated to other physical subscales such as role limitations due to physical problems, good general health and vitality. There was also a discrepancy between measured maximal power and PF in many subjects, particularly in males who experienced either intact or severely reduced PF.

CONCLUSIONS

Our results demonstrate that simultaneous measurements of self-reported and objective measures of PF should add a more integrated view for evaluation of therapeutic effectiveness, since the overall correlation was poor between objective and subjective scores among individuals.

Depressive symptoms and health-related quality of life: the Heart and Soul Study

CONTEXT

Little is known regarding the extent to which patient-reported health status, including symptom burden, physical limitation, and quality of life, is determined by psychosocial vs physiological factors among patients with chronic disease.

OBJECTIVE

To compare the contributions of depressive symptoms and measures of cardiac function to the health status of patients with coronary artery disease.

DESIGN, SETTING, AND PARTICIPANTS

Cross-sectional study of 1024 adults with stable coronary artery disease recruited from outpatient clinics in the San Francisco Bay Area between September 2000 and December 2002. Main Measures Measurement of depressive symptoms using the Patient Health Questionnaire (PHQ); assessment of cardiac function by measuring left ventricular ejection fraction on echocardiography, exercise capacity on treadmill testing, and ischemia on stress echocardiography; and measurement of a range of health status outcomes, including symptom burden, physical limitation, and quality of life, using the Seattle Angina Questionnaire. Participants were also asked to rate their overall health as excellent, very good, good, fair, or poor.

RESULTS

Of the 1024 participants, 201 (20%) had depressive symptoms (PHQ score > or =10). Participants with depressive symptoms were more likely than those without depressive symptoms to report at least mild symptom burden (60% vs 33%; P<.001), mild physical limitation (73% vs 40%; P<.001), mildly diminished quality of life (67% vs 31%; P<.001), and fair or poor overall health (66% vs 30%; P<.001). In multivariate analyses adjusting for measures of cardiac function and other patient characteristics, depressive symptoms were strongly associated with greater symptom burden (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.3-2.7; P =.002), greater physical limitation (OR, 3.1; 95% CI, 2.1-4.6; P<.001), worse quality of life (OR, 3.1; 95% CI, 2.2-4.6; P<.001), and worse overall health (OR, 2.0; 95% CI, 1.3-2.9; P<.001). Although decreased exercise capacity was associated with worse health status, left ventricular ejection fraction and ischemia were not.

CONCLUSIONS

Among patients with coronary disease, depressive symptoms are strongly associated with patient-reported health status, including symptom burden, physical limitation, quality of life, and overall health. Conversely, 2 traditional measures of cardiac function-ejection fraction and ischemia-are not. Efforts to improve health status should include assessment and treatment of depressive symptoms.

Baseline health-related quality of life in postmenopausal women with coronary heart disease: the Estrogen Replacement and Atherosclerosis (ERA) trial

OBJECTIVES

This study examined the baseline health-related quality of life (HRQL) of 301 postmenopausal women with heart disease enrolled in the Estrogen Replacement and Atherosclerosis (ERA) trial.

METHODS

The primary measure of HRQL was the Medical Outcomes Study Short Form-36 (MOS SF-36). The SF-36 was augmented with secondary assessments, including measures of depressive symptoms, life satisfaction, urinary incontinence, sleep disturbance, and physical symptoms. Multiple regression analyses were used to test hypotheses regarding the contribution of positive (social support) and negative (social strain) aspects of social relations after accounting for other correlates of HRQL and heart disease.

RESULTS

Results indicate that social support was positively associated with better functioning for all measured outcomes (all p < 0.05) except symptom frequency and severity. Social strain was negatively associated with HRQL functioning (all p < 0.05) except overall physical functioning, sleep disturbance, and urinary incontinence. In addition, several comorbid conditions were negatively associated with HRQL outcomes. In particular, chest pain was significantly associated with worse functioning on all HRQL outcomes except urinary incontinence.

CONCLUSIONS

These data suggest that both clinical status variables (particularly chest pain) and the psychosocial context (represented by dimensions of relationship quality) influenced HRQL in this cohort. Thus, interventions that combine medical treatments with psychosocially based interventions may be most effective for women at risk for impaired HRQL.

Criteria for definition of regional functional improvement on quantitative post-stress gated myocardial SPET after bypass surgery in patients with ischaemic cardiomyopathy

Myocardial viability can be defined as functional improvement of dysfunctional myocardium after revascularization. The purpose of this study was to define the optimal criteria for definition of regional functional improvement after coronary artery bypass graft (CABG) surgery on quantitative gated single-photon emission tomography (SPET). Thirty-two patients (26 men, 6 women; age 56 +/- 13 years) with coronary artery disease (three-vessel disease, 17; two-vessel disease, 15; previous history of myocardial infarction, 9) and severe left ventricular dysfunction (LVEF < or = 35%) underwent CABG. Rest thallium-201/dipyridamole stress technetium-99m methoxyisobutylisonitrile gated myocardial SPET was performed before and 3 months after CABG. Global LV functional improvement was defined as either an improvement in LVEF of 10% ( n = 15) or an improvement in LVEF of 5% combined with a decrease in end-systolic volume of 10 ml ( n = 2) after CABG on quantitative gated SPET. Postoperative regional wall thickening improvement (DeltaRWT), regional wall motion improvement (DeltaRWM) and regional resting (DeltaRP) and stress perfusion improvement (DeltaRstrP) were used to determine global functional improvement by ROC curve analysis, and the optimal criteria for definition of viable regional dysfunctional myocardium were defined on the ROC curves. Correlations were verified by determining the number of improved myocardial regions and LVEF improvement. LVEF was improved from 25% +/- 6% to 34% +/- 11% after CABG. A total of 229 segments were dysfunctional (wall motion < or = 2 mm, thickening < or = 20%) before CABG. On ROC curve analysis using global functional improvement as an indicator of viability, the areas under the ROC curves (AUCs) of DeltaRWT and DeltaRWM were 0.717 and 0.620, respectively. The AUC of DeltaRWT was significantly larger than that of DeltaRWM ( P = 0.009) and the optimal cut-off value of DeltaRWT was 15%. The AUCs of DeltaRP and DeltaRstrP were not significant. The correlation coefficients between summed DeltaRWT and DeltaRWM and LVEF improvement were 0.591 and 0.472, respectively. The number of segments with a DeltaRWT of more than 15% correlated with LVEF improvement (rho = 0.533 by Spearman rank correlation). Regional wall thickening improvement showed the best correlation with global LV functional improvement after CABG. The most reliable regional criterion of myocardial viability was improvement in regional wall thickening by > or = 15% on quantitative gated SPET.

Association of patients' perception of health status and exercise electrocardiogram, myocardial perfusion imaging, and ventricular function measures

BACKGROUND

Patients' viewpoint of their health status is increasingly used as an important outcome measure of the success of treatments. Because clinicians rarely formally measure patients' health-related quality of life, the question arises whether noninvasive testing for ischemia can provide similar information regarding physical functioning and general health perception.

METHODS

We measured physical functioning and general health status with the Medical Outcomes Study Short Form (SF-36) survey in 195 consecutive patients (68% male, mean age 55.6 +/- 11.1 years) referred for exercise testing with myocardial perfusion imaging. The survey was completed immediately before the exercise test.

RESULTS

In the multivariate analysis, the strongest predictor of physical functioning and general health perception was metabolic equivalents. However, the best model, including demographic, clinical, and test variables, predicted only 14% of the variation in physical functioning and 10% of the variability in general health perception.

CONCLUSIONS

The variation in physical functioning and general health perception, as measured by the SF-36, among patients referred for exercise testing is not predicted well by the results of the test. As expected, several test results are significantly associated with physical functioning and general health perception; however, there was substantial overlap among individual patients, suggesting that the parameters are poor surrogates for the actual assessment of the domains. If these domains are deemed important to tracking patient outcomes, then they should supplement the current assessments of these patients.

Improvement in quality of life differs between women and men after coronary artery bypass surgery

OBJECTIVE

To study improvement in quality of life (QoL) after coronary artery bypass grafting (CABG) in relation to gender.

BACKGROUND

Women generally report worse QoL after CABG than men. However, women are older and more symptomatic prior to surgery, which should be considered in comparative analyses.

METHODS

We studied consecutive patients who underwent CABG between 1988 and 1991 [n = 2121] with a QoL questionnaire containing the Physical Activity Score, the Nottingham Health Profile and the Psychological General Well-being Index prior to, 3 months, 1 year and 2 years after surgery.

RESULTS

Females were older than men with more concomitant diseases preoperatively. QoL was improved on all postoperative occasions for both sexes. Improvement in the Physical Activity Score was somewhat, although not significantly, greater in males. Improvement in the Nottingham Health Profile was greater in females. General well-being showed no consistent pattern for improvement.

CONCLUSIONS

QoL is significantly improved after CABG in both sexes throughout follow-up. There is a complex association between improvement in various aspects of QoL and gender.

Functional status and quality of life in patients with heart failure undergoing coronary bypass surgery after assessment of myocardial viability

OBJECTIVES

The aim of this study was to evaluate whether preoperative clinical and test data could be used to predict the effects of myocardial revascularization on functional status and quality of life in patients with heart failure and ischemic LV dysfunction.

BACKGROUND

Revascularization of viable myocardial segments has been shown to improve regional and global LV function. The effects of revascularization on exercise capacity and quality of life (QOL) are not well defined.

METHODS

Sixty three patients (51 men, age 66+/-9 years) with moderate or worse LV dysfunction (LVEF 0.28+/-0.07) and symptomatic heart failure were studied before and after coronary artery bypass surgery. All patients underwent preoperative positron emission tomography (PET) using FDG and Rb-82 before and after dipyridamole stress; the extent of viable myocardium by PET was defined by the number of segments with metabolism-perfusion mismatch or ischemia. Dobutamine echocardiography (DbE) was performed in 47 patients; viability was defined by augmentation at low dose or the development of new or worsening wall motion abnormalities. Functional class, exercise testing and a QOL score (Nottingham Health Profile) were obtained at baseline and follow-up.

RESULTS

Patients had wall motion abnormalities in 83+/-18% of LV segments. A mismatch pattern was identified in 12+/-15% of LV segments, and PET evidence of viability was detected in 30+/-21% of the LV. Viability was reported in 43+/-18% of the LV by DbE. The difference between pre- and postoperative exercise capacity ranged from a reduction of 2.8 to an augmentation of 5.2 METS. The degree of improvement of exercise capacity correlated with the extent of viability by PET (r = 0.54, p = 0.0001) but not the extent of viable myocardium by DbE (r = 0.02, p = 0.92). The area under the ROC curve for PET (0.76) exceeded that for DbE (0.66). In a multiple linear regression, the extent of viability by PET and nitrate use were the only independent predictors of improvement of exercise capacity (model r = 0.63, p = 0.0001). Change in Functional Class correlated weakly with the change in exercise capacity (r = 0.25), extent of viable myocardium by PET (r = 0.23) and extent of viability by DbE (r = 0.31). Four components of the quality of life score (energy, pain, emotion and mobility status) significantly improved over follow-up, but no correlations could be identified between quality of life scores and the results of preoperative testing or changes in exercise capacity.

CONCLUSIONS

In patients with LV dysfunction, improvement of exercise capacity correlates with the extent of viable myocardium. Quality of life improves in most patients undergoing revascularization. However, its measurement by this index does not correlate with changes in other parameters nor is it readily predictable.

Quality of Life After Coronary Artery Bypass Surgery: Past Progress and Future Directions

Historically, morbidity and mortality have been the primary outcome measures in coronary artery bypass research. Limited health care resources have led to greater emphasis on cost as a primary outcome mea sure. These are each important measures, but they fail to directly assess what patients care about, which is their overall quality of life (QOL). When QOL is used as an outcome in medical research, it should encompass at a minimum the following domains: physical status, mental function, social interaction, and disease-specific measure. Fortunately, QOL assessment instruments already exist that are reliable, valid, and sensitive to change. This article describes how QOL is defined, what instruments are available, how they have been devel oped, and how they are selected. Next, QOL in the coronary artery bypass literature is reviewed. This in cludes both the large randomized trials as well as studies focusing solely on QOL. Finally, future directions for QOL as an outcome measure are examined.