Associations of Dietary Patterns with Objective and Subjective Sleep Duration and Sleep Quality in a Population-Based Cohort Study

Objective: To examine cross-sectional and longitudinal associations of various types of dietary patterns with selfreported sleep quality and with actigraphy-estimated sleep parameters in the prospective, population-based Rotterdam Study. Methods: For each participant, scores for five different dietary patterns were derived based on food frequency questionnaires; two pre-defined scores developed to estimate adherence to the Dutch dietary guidelines and to the Mediterranean diet; and three data-driven scores indicating a prudent, unhealthy and typical Dutch diet. In 2589 participants (median age 56.9 years; 58 % female), self-rated sleep quality was assessed with the Pittsburgh Sleep Quality Index. In 533 participants, actigraphs were worn for an average of 6.8 days (SD: 0.7) to estimate total sleep time, sleep onset latency, wake after sleep onset, and sleep efficiency. Sleep parameters were measured at baseline and 3-6 years later. Multiple linear regression was used to assess cross-sectional and longitudinal associations. Results: No statistically significant associations between dietary patterns and total sleep time, sleep onset latency, wake after sleep onset, sleep efficiency and subjective sleep quality were observed in cross-sectional or longitudinal analyses. To illustrate, the effect estimate for sleep duration was 2.7 min per night (95 % CI -2.1, 7.5) per 5 point increase in Mediterranean diet score in the cross-sectional analyses. Furthermore, in longitudinal analyses, the effect estimate for sleep duration was -1.0 min per night (95 % CI -5.2, 3.1) per SD increase in the prudent diet. Conclusions: Our results suggest that dietary patterns are not associated with sleep in this population-based cohort study. Trial registration: Netherlands National Trial Register and WHO International Clinical Trials Registry Platform (ICTRP; https://apps.who.int/trialsearch/) shared catalogue number NL6645/NTR6831. Registered November 13th, 2017.