Relationship between sleep duration and body mass index depends on age

Abstract

OBJECTIVE Sleep duration is associated with obesity and cardiometabolic disease. It is unclear, though, how these relationship differs across age groups. METHODS Data from the 2007–2008 National Health and Nutrition Examination Survey (NHANES) were used, including respondents aged 16+ with complete data (N=5,607). Sleep duration and age were evaluated by self-report and body mass index (BMI) was assessed objectively. Sleep duration was evaluated continuously and categorically [very short (≤4h), short (5–6h), and long (≥9h) versus average (7–8h)]. Age was also evaluated continuously and categorically [adolescent (16–17yrs), young adult (18–29yrs), early middle age (30–49 yrs), late middle age (50–6 4yrs), and older adult (≥65 yrs)]. RESULTS There was a significant interaction with age for both continuous (Pinteraction=0.014) and categorical (Pinteraction=0.035) sleep duration. A pseudo-linear relationship is seen among the youngest respondents, with the highest BMI associated with the shortest sleepers and the lowest BMI associated with the longest sleepers. This relationship becomes U-shaped in middle-age, and less of a relationship is seen among the oldest respondents. CONCLUSIONS These findings may provide insights for clinical recommendations and could help to guide mechanistic research regarding the sleep-obesity relationship.

Socio-demographic and behavioural determinants of body mass index among an adult population in rural Northern Ghana: the AWI-Gen study

“…This is consistent with similar studies which report that older participants with longer sleep duration were likely to have lower BMI [55]. Sedentary time, however, was associated with higher BMI among both men and women.…”

Sleep, Health, and Society

“…First, this relationship is dependent on age, with the strongest relationships among younger adults and U-shaped relationships more common in middle-aged adults. 47 Also, this relationship may be moderated by race/ethnicity, with stronger relationships between sleep and obesity among non-Hispanic white and black/African American adults. 24 …”

Sleep duration and the associated cardiometabolic risk scores in adults

“…20,21,24 The shape of the relationship between sleep duration and cardiometabolic risks may also vary in different age groups: Grandner and colleagues 21 found a linear relationship in younger adults and a U-shaped relationship in middle-aged adults. Aging is also considered as a risk factor for cardiometabolic dysfunction, and it is associated with increased inflammation and oxidative stress, as well as decreased antioxidant capacities, which may partially explain the higher cardiometabolic risk score seen in older adults in our study.…”

“…16 Previous studies have also found that several individual cardiometabolic risk factors are optimal among 7 to 8 h sleepers, 17,18 but poor sleep patterns and the prevalence of cardiometabolic risks are also higher in subgroups such as men, older adults, non-Hispanic Blacks, and smokers. [19][20][21][22][23][24][25] Further, the relationship between sleep duration and cardiometabolic risk may be U-shaped. 14,18 The relationship between sleep duration Sleep Health xxx (2017) xxx-xxx and a continuous measure of cardiometabolic risk may also be moderated by sex, age, ethnicity, and smoking status, which have been considered as confounding variables in previous studies, 4,13 but they may be significant moderators of the relationship.…”