Relationship between MSpO2 and depressive symptoms in older patients with obstructive sleep apnea: a cross-sectional study.

OBJECTIVE

This study explored risk factors associated with depressive symptoms in older patients with obstructive sleep apnea (OSA) and assessed correlations of mean pulse oxygen saturation (MSpO2) with depressive symptoms.

METHODS

In total, 1,085 older patients diagnosed with OSA via polysomnography (PSG) were included. Based on scores from the 12-item Geriatric Depression Scale (GDS-12), participants were classified into two subgroups to identify depressive symptom-related risk factors. Logistic regression analysis, restricted cubic splines, and subgroup analyses were performed to evaluate correlations of MSpO2 with depressive symptoms.

RESULTS

Depressive symptoms were observed in 139 patients (12.8% of the sample). Logistic regression analysis indicated that age (per 1-year increase, odds ratio [OR] = 1.11, 95% confidence interval [CI]: 1.08-1.14; P < 0.001), smoking (OR = 1.66, 95% CI: 1.02-2.69; P = 0.041), MSpO₂ (per 1% increase, OR = 0.90, 95% CI: 0.85-0.94; P < 0.001), diabetes mellitus (OR = 1.61, 95% CI: 1.03-2.51; P = 0.038), and renal dysfunction (OR = 2.26, 95% CI: 1.10-4.66; P = 0.027) were significantly associated with depressive symptoms. Additionally, sleep parameters including AHI, ODI, and LSpO₂ were independently associated with depressive symptoms. Restricted cubic splines suggested a linear correlation between MSpO₂ and depressive symptoms (nonlinear P = 0.38). Compared with patients in the highest category (MSpO₂ ≥ 95.0%), those in the lowest category (MSpO₂ ≤ 91.7%) showed increased depressive symptom risk (OR = 2.25, 95% CI: 1.34-3.78, P = 0.002). Subgroup analyses confirmed this linear relationship.

CONCLUSION

A linear correlation exists between MSpO2 and depressive symptoms in older patients with OSA. Additionally, age, smoking, diabetes mellitus, and renal dysfunction are strongly associated with depressive symptoms in this population.