Effect of Underlying Cardiometabolic Diseases on the Association Between Sedentary Time and All-Cause Mortality in a Large Japanese Population: A Cohort Analysis Based on the J-MICC Study.

Background This study aimed to determine the association between sedentary time and mortality with regard to leisure-time physical activity with or without cardiometabolic diseases such as hypertension, dyslipidemia, and diabetes mellitus. Methods and Results Using data from the J-MICC (Japan Multi-Institutional Collaborative Cohort) Study, 64 456 participants (29 022 men, 35 434 women) were analyzed. Hazard ratios (HRs) and 95% CIs were used to characterize the relative risk of all-cause mortality to evaluate its association with sedentary time (categorical variables: <5, 5 to <7, 7 to <9, ≥9 h/d and 2-hour increments in exposure) according to the self-reported hypertension, dyslipidemia, and diabetes mellitus using a Cox proportional hazards model. A total of 2257 participants died during 7.7 years of follow-up. The corresponding HRs for each 2-hour increment in sedentary time among participants with all factors, no factors, hypertension, dyslipidemia, and diabetes mellitus were 1.153 (95% CI, 1.114-1.194), 1.125 (95% CI, 1.074-1.179), 1.202 (95% CI, 1.129-1.279), 1.176 (95% CI, 1.087-1.273), and 1.272 (95% CI, 1.159-1.396), respectively. Furthermore, when analyzed according to the combined different factors (hypertension, dyslipidemia, and diabetes mellitus), HRs increased with each additional factor, and participants reporting all 3 conditions had the highest HR of 1.417 (95% CI, 1.162-1.728) independently of leisure-time metabolic equivalents. Conclusions The association between sedentary time and increased mortality is stronger among patients with hypertension, dyslipidemia, and diabetes mellitus regardless of leisure-time physical activity in a large Japanese population.