The Association Between Weekend Catch‐Up Sleep and Obesity: A Systematic Review and Dose–Response Meta‐Analysis

Background The relationship between weekend catch‐up sleep (WCS) and weight and obesity remains controversial. The aim of this systematic review and meta‐analysis was to determine the association between WCS and obesity and to explore the dose–response effect between these two factors. Methods We conducted a meta‐analysis with a comprehensive search of electronic databases from inception. Heterogeneity was assessed using the Chi‐squared (Q) test and I 2 statistic. Different subgroup analyses will be conducted, such as gender, age, WCS durations, weekday sleep deprivation, and obesity definition. Leave‐one‐out sensitivity analyses were performed by removing a single study each time, to assess whether the results of this meta‐analysis were robust. Publication bias was explored using the funnel plot. The potential linear or nonlinear dose–response effect was evaluated using a restricted cubic splines regression model. Results A total of 11 studies, comprising a total of 149,795 participants, were included. The pooled analysis using a random‐effects model demonstrated a significant association between WCS and reduced obesity risk (OR = 0.79, 95% CI: 0.70–0.89, p < 0.001). In subgroup analysis by weekday sleep deprivation, an association was observed among three subgroups with weekday sleep deprivation (OR = 0.73, 95% CI: 0.55–0.97, p = 0.027), while no clear correlation was shown among three subgroups without weekday sleep deprivation (OR = 0.90, 95% CI: 0.78–1.06, p = 0.206). Moreover, obesity was associated with 0 < WCS< 1 h (OR = 0.85, 95% CI: 0.77–0.94, p = 0.001) and 1 < WCS< 2 h (OR = 0.85, 95% CI: 0.78–0.94, p = 0.001) when compared with the reference group. Furthermore, WCS was associated with those BMI above 25 kg/m 2 criteria (OR = 0.77, 95% CI: 0.60–0.99, p = 0.042) and BMI z‐score > 95th percentile criteria: (OR = 0.81, 95% CI: 0.66–0.99, p = 0.040), whereas no significant association was observed in studies using BMI above 30 kg/m 2 criteria (OR = 1.03, 95% CI: 0.98–1.06, p = 0.417). When stratified by age, an association was observed among adults (OR = 0.73, 95% CI: 0.55–0.97, p = 0.030) and adolescents (OR = 0.77, 95% CI: 0.65–0.91, p = 0.002), whereas no clear association was seen among children (OR = 0.82, 95% CI: 0.66–1.01, p = 0.073). A nonlinear relationship was observed between WCS and the risk of obesity, where moderate WCS may reflect an attempt to compensate for sleep debt, and excessive or irregular sleep extension was associated with higher odds of obesity. Conclusions WCS may be associated with a lower risk of overweight or obesity. More prospective studies incorporating objective sleep metrics are needed to verify the dose–response association and underlying biological pathways.