Impact of CPAP therapy on geriatric depression scale scores in elderly patients with obstructive sleep apnea

The aim of this study is to investigate the effect of CPAP treatment on depression scores in OSA, which is associated with impaired quality of life and functional decline in the geriatric population.

The study was an ambispective cohort involving geriatric patients aged 65-80 with moderate-to-severe OSA confirmed by polysomnography. Initial depressive symptoms were assessed using the Geriatric Depression Scale (GDS). Participants were categorized based on their adherence to CPAP. Objective CPAP usage data, including mean nightly usage time and the percentage of nights used, were obtained from device downloads. Baseline predictors of depression were examined using multiple linear regression. The effect of CPAP adherence on post-treatment GDS scores was analyzed with analysis of covariance (ANCOVA), adjusting for initial depression scores. The model was also run with body mass index, lowest oxygen saturation and follow-up duration as additional covariates, and effect sizes were calculated.

Of the 53 patients, 31 (58.5%) adhered to CPAP. Demographic and clinical characteristics were similar between adherent and non-adherent groups. Regression analysis showed that lower nocturnal oxygen saturation (p = 0.012) and higher body mass index (BMI) (p = 0.011) were independently associated with higher initial GDS scores, while the apnea-hypopnea index was not significantly related to depressive symptoms. After adjusting for initial GDS scores, the adherent group had significantly lower post-treatment depression scores compared to non-adherents (adjusted mean GDS: 7.15 ± 0.18 vs. 10.10 ± 0.21, p < 0.001). The adjusted mean difference was 2.95 points (95% CI 2.40-3.50; partial η² = 0.70). Mean nightly use was 6.44 ± 0.97 h in the adherent group and 2.41 ± 0.95 h in the non-adherent group, on 88.4 ± 15.0% and 36.0 ± 25.0% of nights respectively (p < 0.001).

CPAP adherence was associated with a significant reduction in depressive symptoms in older adults with OSA. Nocturnal hypoxemia and obesity were key predictors of depression severity. These findings suggest that effective OSA treatment may improve mental health outcomes in the elderly.