Frequency and impact of lifestyle modification in patients with coronary artery disease: The Japanese Coronary Artery Disease (JCAD) Study

Background Lifestyle modifications such as exercise and diet interventions in patients with coronary artery disease (CAD) are widely regarded as important, but little is known about their frequency in clinical practice and their impact on all-cause mortality. Methods The JCAD study is a cohort study of 13,812 patients with CAD (≥75% stenosis in ≥1 of 3 major coronary arteries). Patients were enrolled from April 2000 through March 2001 at 202 institutions throughout Japan. Exercise and diet interventions were defined based on Japanese national guidelines. Cox proportional hazards models were used to calculate hazard ratios (HRs) for all-cause mortality with 95% CIs. Results We studied 11,893 patients in the JCAD study. Over 3 years of follow-up, there were 474 deaths; 4,237 patients (35.6%) underwent exercise intervention, and 8,642 patients (72.7%) underwent diet intervention from the time of discharge. Mortality was lower in patients who underwent an exercise or diet intervention than in patients who did not: HR 0.68 (95% CI 0.56-0.84) and 0.75 (95% CI 0.62-0.91), respectively. After adjustment for age, sex, institution, hypertension, hyperlipidemia, diabetes, obesity, current drinking, current smoking, and the use of antiplatelet agents, β-blockers, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and statins, the associations with these interventions remain statistically significant: HR 0.73 (95% CI 0.55-0.96) for exercise and 0.74 (95% CI 0.58-0.95) for diet interventions. Conclusions Exercise and diet interventions have a beneficial impact on all-cause mortality in patients with CAD, yet these interventions are surprisingly infrequent. Lifestyle interventions should be more actively promoted.