Objectives: The diagnosis of early-onset Alzheimer's disease (EOAD) can cause emotional stress not only to the patients themselves but also to their spouses. This study aimed to evaluate the risk of psychiatric disorders in spouses of EOAD patients, using psychotropic drug initiation as a surrogate indicator.
Methods: A cohort study was conducted using a Japanese claims database, with spouses of EOAD patients (exposed spouses) matched with spouses of non-EOAD individuals (reference spouses) up to a 1:10 ratio. Primary outcome was the initiation of mood disorder drugs, and secondary outcomes were the initiation of drugs for anxiety disorders, sleep disorders, and schizophrenia spectrum disorders. Four study cohorts were created according to each outcome analysis. Multivariable Cox regression models were used to estimate adjusted hazard ratios (aHRs) and their 95% confidence intervals (CIs) for study outcomes.
Results: The analysis of mood disorder drugs included 395 exposed spouses and 3711 reference spouses. The proportion of patients excluded from the analysis due to prescription of mood disorder drugs during the baseline period was 4.3% higher among exposed spouses than reference spouses. There was no major difference between groups with respect to mood disorder drug initiation after 1 year (aHR, 2.08 [95% CI, 0.61 to 7.13]). In subgroup analysis of females and dependents, exposed spouses showed a higher rate of initiation (females: aHR, 6.39 [95% CI, 1.24 to 32.80]; dependents: aHR, 6.47 [95% CI, 1.25 to 33.55]). No substantial differences in secondary outcomes were observed in any comparison.
Conclusions: This study does not conclusively demonstrate an increase in mood disorder drug initiation among spouses of EOAD patients overall; however, initiation rates may be higher among female or dependent spouses. Our findings also suggest that exposed spouses experience significant psychological stress prior to their partners' EOAD diagnoses.
Keywords: caregiver; early‐onset Alzheimer's disease; psychiatric disorder; psychotropic drug; spouse.
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