Understanding insomnia in older adults.

OBJECTIVE

The aims of this study were to determine the true frequency of primary insomnia (PI), sleep disorder related to another mental disorder (SDMD) and sleep disorder due to a general medical condition (SDMC) in older adults and to establish their differentiating characteristics.

METHODS

This is a cross-sectional study. Participants were randomly selected samples of 951 subjects who are 65 years or older. Main measures were as follows: presence (according to DSM-IV-TR diagnostic criteria) of PI, SDMD, SDMC or other sleep disorders, co-morbidity and psychotropic consumption.

RESULTS

Of the subjects, 36.1% reported having sleep problems (95% CI: 33.0-39.2) and 37.0% reported regularly consuming a psychotropic drug. The prevalence of PI was 8.9% (95% CI: 7.1-11.0), and according to the criteria for differential diagnosis, the prevalence of SDMD was 9.3% (95% CI: 7.5-11.4) and that of SDMC was 7.0% (95%CI: 5.4-8.9). A higher percentage of PI subjects had problems in falling asleep on most days (52.5%), had frequent night-time awakenings (66.3%) and early awakenings (51.3%). In subjects with any type of insomnia, the variables that showed a statistically significant association were female gender (OR: 2.21), consumption of psychotropic drugs (OR: 1.83), presence of four or more health problems (OR: 1.88) and being single, widowed or divorced (OR: 1.43).

CONCLUSIONS

Our results provide a true picture of the prevalence of insomnia in older adults on the basis of diagnostic criteria and indicate that it is a widespread, significant health problem. The peculiarities of PI, SDMD and SDMC need to be appropriately differentiated in clinical practice, and each needs a different approach to obtain the best outcome.