Sleep quality and duration - potentially modifiable risk factors for Coronary Artery Disease?

PURPOSE

Previous studies have shown that lack of sleep exerts deleterious effects on a variety of systems with detectable changes in metabolic, endocrine and immune pathways. Both short and long sleep durations are related to increased likelihood of diabetes and hypertension. However, the relation between sleep duration, sleep quality and Coronary Artery Disease (CAD) is not clear in the Indian population. We examined the hypothesis that sleep duration (compared with <6 h) and quality of sleep (PSQI > 5) are risk factors for CAD.

METHODS

A retrospective & controlled study was conducted on 352 adult (>18 yrs) subjects (176 controls and 176 cases, 60% men, age M = 51 ± 9.38). Sleep quality and duration was measured with Pittsburg Sleep Quality Index (PSQI). Poor sleep quality and short sleep duration was defined as PSQI >5 and total sleep time <6.0 h, respectively. OSA patients were excluded from the study. The main outcome of interest was the presence of any CAD (n = 176), including MI, angina, and stroke. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated using Multivariate Logistic Regression analysis.

RESULTS

We found both poor quality of sleep and short sleep duration to be independently associated with CAD. Compared with a total sleep time of 6.0 h, the multivariate odds ratio (95% confidence interval) of CAD was 3.81 (1.69-8.58) whereas for poor sleep quality (PSQI > 5) it came out to be 16.62 (9.13-30.28).

CONCLUSION

There was a positive association between both short sleep duration and poor sleep quality with CAD in a selected sample of Indian adults. These results suggest that poor sleep quality and short sleep duration may be important modifiable CAD risk factors in the Indian population.