Are sleep disorders hereditary? A questionnaire survey of elderly persons about themselves and their parents

The aim of the present study was to investigate the occurrence of sleep complaints in an elderly population in relation to the sleep pattern in their parents. The study is based on a postal questionnaire, which was sent to 10 216 elderly persons in northern Sweden. The mean (s.d.) ages of the participating men and women were 73.0 (6.0) and 72.6 (6.7) years, respectively. Among the men whose parents had no sleep problems, a good nightʹs sleep was reported by 11.1%, and among those whose parents both had such problems, this proportion was 18.9%. The corresponding figures for women were 20.6% and 60.0%, respectively. Restless sleep, frequent awakening, difficulty in getting to sleep again after waking up in the night as well as tiredness at night but with inability to get to sleep was more common in both sexes if either of the parents had difficulty in sleeping, and even more common if such problems had occurred in both parents. Also visits to doctors because of sleep problems and treatment with sleeping pills were more common in both men and women whose parents had had sleep problems, compared with those whose parents had been good sleepers. Thus, a poor sleep was more common in elderly persons if their parents had sleep problems, compared with those whose parents had been good sleepers. The results suggest that hereditary factors could be an underestimated cause of sleep disorders in the elderly.