Association between sleep parameters and metabolic syndrome among healthy middle-aged Koreans

Abstract

BACKGROUND

Sleep has been recognized as one of the important factors related to various health problems. Several studies have reported that sleep status affects the morbidity of metabolic syndrome; however, there are limited studies, particularly in Korea. Thus, the current study evaluates the association of sleep parameters including sleep duration, difficulty in sleep initiation, and obstructive sleep apnea (OSA) risk with metabolic syndrome in healthy middle-aged Koreans.

METHODS

This study used data from 1,659 participants (588 of male and 1,071 of female) aged 30 to 64 years enrolled in the Cardiovascular and Metabolic diseases Etiology Research Center (CMERC) study conducted between 2013 and 2014. Multiple logistic regression models were used to examine the associations between sleep parameters and metabolic syndrome.

RESULTS

Male participants with short sleep duration exhibited 3.41 times higher odds (95% confidence interval (CI) 1.40-8.28) of having metabolic syndrome after adjusting for age, body mass index, smoking status, drinking status, physical activity, depression, and risk of OSA. On the other hand, female participants with difficulty in sleep initiation for 1-4 days/week were at higher risk for metabolic syndrome (adjusted odds ratio (OR) 1.75; 95% CI 1.06-2.89) than those without difficulty in sleep initiation. People with short sleep duration and difficulty in sleep initiation had a higher risk of metabolic syndrome (adjusted OR 4.94; 95% CI 1.05-23.21 in males, 2.23; 95% CI 1.01-4.94 in females) than those with intermediate sleep duration and no difficulty in sleep initiation. Corresponding OR for people with short sleep duration and no difficulty in sleep initiation was 3.34 (95% CI 1.15-9.67) in males, 1.36 (95% CI 0.50-3.72) in females. The high risk of OSA group exhibited an increased risk of abdominal obesity with an adjusted OR of 3.61 (95% CI 2.76-4.71) and high blood pressure with an OR of 2.39 (95% CI 1.82-3.14) compared to the low risk of OSA group.

CONCLUSION

Our study suggested that short sleep duration and difficulty in sleep initiation are associated with metabolic syndrome among healthy middle-aged Koreans. The results of our study also imply that it is important to assess the quantitative and qualitative aspects of sleep. In addition, the high risk of OSA group was associated with components of abdominal obesity and high blood pressure. However, considering the indicators for determining the risk of OSA, including body mass index and diagnosed hypertension, caution is needed in interpretation.