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
Sandhu et al. (Fri,) studied this question.