Insomnia Symptoms in Older Adults: Associated Factors and Gender Differences

Objectives: The aim of this study was to examine the factors associated with insomnia in community-dwelling elderly as a function of the nature and number of insomnia symptoms (IS), e. g., difficulty with initiating sleep (DIS), difficulty with maintaining sleep (DMS), and early morning awakening (EMA). Methods: IS were assessed in a sample of 2,673 men and 3,213 women aged 65 years and older. The participants were administered standardized questionnaires regarding the frequency of IS and other sleep characteristics (snoring, nightmares, sleeping medication, and sleepiness) and various sociodemographic, behavioral and clinical variables, and measures of physical and mental health. Results: More than 70% of men and women reported at least one IS, DMS being the most prevalent symptom in both men and women. Women reported more frequently two or three IS, whereas men reported more often only one IS. Multivariate regression analyses stratified by gender showed that men and women shared numerous factors associated with IS, sleeping medication, nightmares, sleepiness, chronic diseases, and depression being independently associated with two or three IS. For both sexes, age was associated with only one IS in all age categories. Loud snoring was strongly associated with increased DMS in men only. High body mass index increased the risk for DIS in men but tended to decrease it in women. In women, hormonal replacement therapy, Mediterranean diet, and caffeine and alcohol intake had a protective effect. Conclusion: Our data suggest that women may have specific predisposition factors of multiple IS, which may involve both behavioral and hormonal factors. Identification and treatment of these risk factors may form the basis of an intervention program for reduction of IS in the elderly. (Am J Geriatr Psychiatry 2010; 19:88-97)