0795 Polysomnographic and Clinical Associations of Comorbid Obstructive Sleep Apnea and Restless Legs Syndrome (Co-ROSA)

Abstract Introduction The coexistence of obstructive sleep apnea (OSA) and restless legs syndrome (RLS), recently termed Co-ROSA, has been increasingly recognized but remains underexplored. This study aimed to compare comorbidities, sleep architecture, and psychiatric outcomes in patients with Co-ROSA with controls, OSA, and RLS alone. The central research question was whether Co-ROSA represents a distinct phenotype with amplified risk for specific comorbidities. Methods We studied adults undergoing in-laboratory polysomnography (PSG) at an academic sleep center. Patients were classified into four groups: Group 0 (neither condition), Group 1 (OSA only), Group 2 (Co-ROSA), and Group 3 (RLS only). Demographics, comorbidities, medication use, and PSG parameters were compared between groups using ANOVA, chi-square tests, and multivariable logistic regression. We examined associations with medical and psychiatric comorbidities, adjusting for age, sex, BMI, and medication use. Results A total of 153 patients were included. The mean age was 58.0 ± 21.1 years in Group 0, 54.6 ± 19.9 in Group 1, 54.2 ± 16.2 in Group 2, and 64.8 ± 12.7 in Group 3. The proportion of male participants was 55.6% in Group 0, 60.0% in Group 1, 56.5% in Group 2, and 37.5% in Group 3. Patients with Co-ROSA (group 2) had longer sleep latency (23.9 ± 22.2 minutes), shorter total sleep time (330.8 ± 67.5 minutes), and higher WASO (wake after sleep onset: 74.7 ± 53.3 minutes) compared to Groups 0 and 1, although not statistically significant. Group 2 also exhibited the highest rates of anxiety (63.2%) and depression (52.6%) compared to all other groups (p < 0.05). Regression analyses confirmed Co-ROSA as an independent predictor of both anxiety (OR 1.69, 95% CI 1.07–2.67, p=0.023) and depression (OR 1.84, 95% CI 1.10–3.09, p=0.021). When compared to OSA alone, patients with Co-ROSA had fourfold higher odds of anxiety (OR 4.24, 95% CI 1.47–12.26) and higher odds of depression (OR 2.94, 95% CI 1.04–8.31). Odds ratios for other medical comorbidities, including diabetes, hypertension, chronic kidney disease, peripheral neuropathy, and insomnia, did not reach statistical significance. Conclusion Patients with Co-ROSA represent a high-risk subgroup with disproportionately elevated risk of depression and anxiety independent of demographic and pharmacologic confounders. Polysomnographic, comorbidities, or medication use were not statistically significant. Support (if any) none