Factors influencing persistent subjective insomnia in old age: a follow-up study of good and poor sleepers aged 65 to 74.

Of 82 subjective insomniacs aged 65-74 years identified during a community survey and classified on the basis of self-reported sleep quality, 69 (84%) continued to complain of poor sleep when re-interviewed 18-24 months later. When compared with a control group of similarly stable 'good sleepers' (n = 64) drawn from the same community sample these persistent subjective insomniacs showed significantly higher levels of constitutional (trait) and transitory (state) anxiety, and neuroticism. Discriminant analysis indicated that elevated levels of neuroticism, reduced health status (as measured by the number of drugs prescribed) and relatively high levels of tea consumption were most closely associated with persistent complaints of poor sleep. Thus, despite the existence of health problems as a major cause of sleep disturbance in later life, personality factors appear to exert a pervasive influence on subjective sleep quality among the 'younger' elderly.