Objectives: To assess the prevalence rate of mood disorders, anxiety disorders, benzodiazepine dependence, and insomnia in older men and women with probable cognitive impairment no dementia (CIND) and to examine the independent associations between each disorder and CIND.
Method: Participants were a random sample of community-dwelling individuals aged 65-96 (N = 2414). Semi-structured in-home interviews based on DSM-IV-TR (DSM, Diagnostic and Statistical Manual of Mental Disorders) criteria evaluated the prevalence rates of mood disorders, anxiety disorders, benzodiazepine dependence, and insomnia. Participants were classified as probable CIND based on their Mini-Mental State Examination score using sex, age, and education-stratified cut-offs (lower than the 15th percentile).
Results: In men, 22.7% of individuals with probable CIND and 12.1% of those with normal cognition had at least one psychiatric disorder (crude odds ratio (OR): 2.13, 95% confidence interval (CI): 1.23-3.69). More specifically, mood disorders (3.43, 1.74-6.75), benzodiazepine dependence (5.10, 1.23-21.11), and comorbid anxiety and mood disorders (8.67, 2.00-37.68) were significantly associated with probable CIND, but not anxiety disorders alone and insomnia. The prevalence rate of psychiatric disorders was similar in women with probable CIND (23.1%) and in women without CIND (23.9%; 0.95, 0.64-1.42). No specific psychiatric disorder was significantly associated with probable CIND in women. All associations remained unchanged after adjustments for potential confounders.
Conclusions: The association between psychiatric disorders and probable CIND appears to be sex-specific. In clinical practice, mood disorders, and benzodiazepine dependence should receive particular attention since these disorders are associated with a condition increasing the risk of dementia.