臺灣地區成人睡眠時數與肥胖的相關性研究

The Association between Sleep Duration and Obesity in Taiwanese Adults

研究目的：半個世紀以來，肥胖的盛行率大幅增加，而睡眠時數卻明顯減少。關於睡眠時數與肥胖的關係，雖然多數歐美國家的研究結果支持睡眠時數減少會伴隨體重的增加，但在亞洲國家這方面的研究不多且結論不一致，因此本研究以台灣地區成人為研究對象探討睡眠時數與肥胖的相關性。研究方法：本研究採橫斷面設計，以2001年至2007年間於成大醫院接受健康檢查之成人為研究對象，共計2,929人（其中男性1,870人，女性1,059人）納入統計分析，平均年齡為50.5±12.8歲。肥胖的定義係以身體質量指數(BMI)≧25 kg/m2為切點；而睡眠時數採問卷調查並分為三組（<6, 6~8, ≧8小時），並進一步調整年齡、婚姻狀況、教育程度、收縮壓、運動、吸菸、飲酒及喝咖啡習慣，以線性複迴歸分析探討兩性睡眠時數與BMI的關係。研究結果：單變項分析中，女性肥胖者比非肥胖者的平均睡眠時數少，達統計學上之差異（6.2±1.3 vs. 6.5±1.1小時，p=0.001），而在男性則無明顯差異（6.5±1.1 vs. 6.5±1.1小時，p=0.581）。以線性複迴歸分析發現在男性族群中，已婚、收縮壓、喝咖啡習慣、飲酒習慣及睡眠時數小於6小時為BMI的獨立相關因子；在女性族群中則為年齡、已婚、收縮壓及睡眠時數小於6小時。以複邏輯迴歸分析則顯示男性中已婚及收縮壓高者較易肥胖；而女性中睡眠時數＜6小時及收縮壓高者較易肥胖。結論：本研究發現在台灣地區成人睡眠時數減少是BMI的獨立相關因子，不論男性或女性，睡眠時數小於6小時者有較高的身體質量指數；女性中睡眠時數＜6小時者較易肥胖。因此臨床上在評估肥胖的相關危險因子時，除了要注意飲食與運動等因素外，仍應注意睡眠時數對肥胖的影響。

Purpose: Over the past half century, the prevalence of obesity has increased dramatically, while sleep duration has diminished. Several studies conducted in the West have suggested that short sleep duration is associated with increased body weight; in Asia, however, there have been few studies, and their results have been inconsistent. Therefore, the aim of this study was to investigate the relationship between sleep duration and obesity in Taiwanese adults. Methods: This cross-sectional study enrolled 2,929 subjects (1,870 men and 1,059 women) with mean age of 50.5±12.8 years, who received health examination in National Cheng Kung University Hospital during 2001 and 2007. Obesity was defined as body mass index (BMI) ＞25 kg/m2. Subjects were classified by sleep duration into one of three categories (＜6 hours, 6 to 8 hours, ＞8 hours). We applied linear regression to explore the relationship between sleep duration and obesity by gender, adjusting for age, marital status, education level, systolic blood pressure, exercise, smoking, alcohol consumption, and coffee consumption. Results: The sleep duration of obese women was significantly shorter than that of nonobese women (6.2±1.3 vs. 6.5±1.1 hours, p=0.001), but there was no difference in men (6.5±1.1 vs. 6.5±1.1 hours, p=0.581). Multiple linear regression analysis showed that being married, systolic blood pressure, habitual coffee drinking, habitual alcohol drinking, and sleep duration ＜6 hours were independently associated with BMI in men; age, being married, systolic blood pressure, and sleep duration ＜6 hours were independently associated with BMI in women. Conclusion: Our study revealed that short sleep duration was associated with elevated BMI in Taiwanese men and women; furthermore, sleep duration ＜6 hours was associated with increased risk for obesity in women. Therefore, in addition to diet and exercise, sleep duration should be considered when evaluating risk factors for obesity.