Association of different folate statuses with sleep disturbances in adults in the US: Data from NHANES 2007-2016.

Abstract

Objective: To explore the associations between three folate statuses (folate intake, serum folate, and red blood cell folate) and sleep disturbances in adults.

Methods: Trends in sleep disturbances in five consecutive cycles were evaluated using Cochran-Armitage tests. Survey-weighted logistic regression models, restricted cubic spline models, and interaction analysis were used to evaluate the associations between different statuses of folate and sleep disturbances.

Results: This cross-sectional study included 20,200 eligible adults from five cycles of NHANES (2007-2016). The overall crude prevalence of sleep disturbances increased over time from 25.8% (95% confidence intervals, 23.6%, 28.0%) in 2007-2008 to 29.3% (95% confidence intervals, 25.9%, 32.9%) in 2015-2016 (P for trend <.001). In adjusted, weighted multivariable regression models, compared to the second quartile (Q2), lower folate intake levels (Q1, odds ratio=1.22, 95% confidence intervals: 1.06, 1.40), higher folate intake levels (Q4, odds ratio=1.18, 95% confidence intervals: 1.01, 1.38), and higher red blood cell folate levels (Q4, odds ratio=1.17, 95% confidence intervals: 1.03, 1.33) were independently associated with higher odds of sleep disturbances. The restricted cubic spline models revealed U-shaped, nonlinear associations between different folate statuses and the risk of sleep disturbances. A daily folate intake of approximately 439 mcg, a serum folate concentration of approximately 35nom/L, and an red blood cell folate concentration of approximately 886nmol/L were associated with the lowest risk of sleep disturbances. The results were robust in interaction and sensitivity analyses.

Conclusions: We observed U-shaped associations between folate intake, serum folate, red blood cell folate, and sleep disturbances among US adults.