Insomnia, Depression Closely Related in Older Adults

 Since insomnia and depression often coexist in older adults (OAs), researchers evaluated whether symptoms are linked and found despite previous data, the conditions constitute no additional risk for one another.

Study authors utilized a sample of 3081 community-dwelling OAs and over the course of 20 years with measurements at 3-year intervals. Each individual’s longitudinal reciprocal relationship between symptoms of depression was measured using the Center for Epidemiological Studies Depression Scale. Insomnia symptoms were evaluated using a 3-item questionnaire, which included nightly awakenings, difficulty initiating sleep, and early morning awakenings.

Findings showed a moderate correlation (correlation of intercepts: rho .41, 95% CI: .36 to .46 P < .001; correlation of slopes: rho .39, 95% CI: .25 to .52, P < .001) between OAs within-individual average change over time and severity of symptoms of insomnia and depression.

In 3-year results, study authors noted no association of an additional risk of higher symptoms of insomnia related to symptoms of depression (P = 0.329 and P = 0.919, respectively). Furthermore, researchers reported similar results when analyses were corrected for covariates.

“In older individuals, depression and insomnia are associated and tend to increase concurrently over time, but constitute no additional risk for one another over repeated 3-year intervals,” concluded authors of the study. “These findings contradict previous research that suggests that depression and insomnia are risk factors for one another over time.”

Researchers also noted that while this study stands out based on its longitudinal within-individual approach, limitations also exist due to the 3-year intervals between measurements.

Reference:
Brouwer A, van de Ven PM, Kok A, Snoek FJ, Beekman ATF, Bremmer MA. Symptoms of depression and insomnia in older age: a within-individual analysis over 20 years. J Am Ger Soc. Published online April 6, 2022. doi:10.1111/jgs.17765