Genetic risk for subjective reports of insomnia associate only weakly with polygraphic measures of insomnia in 2,770 adults

Subjective insomnia complaints and objective sleep changes are mostly studied outside of clinical trial studies. In this study, we tested whether 240 genetic variants associated with subjectively reported insomnia were also associated with objective insomnia parameters extracted from polysomnographic recordings (PSG) in three studies. The study sample (total N = 2,770) was composed of the Wisconsin Sleep Cohort (N = 1,091) and the Osteoporotic Fractures in Men (N = 1,026) study, two population-based studies, and the Stanford Sleep Cohort, a sleep center patient-based sample (N = 653). Seven objective PSG features related to insomnia defined outcome variables, with each variant allele serving as predictor. Meta-regression was performed, accounting for common confounders as well as variance differences between studies. Additionally, a normalized genetic risk score (nGRS) was generated for each subject to serve as a predictor variable in separate linear mixed models assessing objective insomnia features. After correction for multiple testing, single nucleotide polymorphisms (SNPs) associated with subjective insomnia were not significantly associated with 6 of 7 objective sleep measures. Only periodic limb movement index (PLMI) was significantly associated with rs113851554 (MEIS1), as found in previous studies. The nGRS was only weakly associated with arousal index and duration of wake after sleep onset. Our findings suggest that subjective insomnia does not have a strong genetic signature mapping onto objective (PSG) sleep variables.