Associations of sleep durations and sleep-related parameters with metabolic syndrome among older Chinese adults.

PURPOSE

There is a lack of data on the role of sleep in the development of metabolic syndrome (MetS) in older adults. We aimed to examine the associations of sleep durations at night and other sleep-related parameters with the presence of MetS in older Chinese adults.

METHODS

Data of 4579 individuals aged 60 years or older from the Weitang Geriatric Disease Study were analyzed. MetS was diagnosed based on the Adult Treatment Panel III (ATP III) criteria. Information regarding sleep durations and other sleep-related parameters was collected by questionnaires.

RESULTS

Compared with those with daytime napping, individuals without daytime napping were at an increased risk of MetS (odds ratio [OR] = 1.23; 95% confidence interval [CI] = 1.03-1.47). Each hour increase in daytime napping increased the risk of MetS by 33% (OR = 1.33; 95% CI = 1.15-1.52). After adjusting for the effect of age and gender, a J-shaped association between sleep durations at night and the presence of MetS was observed. The risk of MetS was lowest among those who slept 7-8 h at night. Gender-stratified analysis indicated that the J-shaped relationship between sleep durations at night and MetS remained significant in men but not in women.

CONCLUSIONS

In older Chinese adults, sleep durations at night might have a dual effect on the risk of MetS and this effect was particularly pronounced in men. The results indicated that circadian rhythm might play an important role in the development of MetS in older populations.