Co-morbid insomnia and obstructive sleep apnea (COMISA) and cardiovascular risk: A scoping review

INTRODUCTION: COMISA, defined as the co-occurrence of obstructive sleep apnoea (OSA) and chronic insomnia, is a common clinical phenotype associated with increased morbidity. While OSA and insomnia have been described as potential cardiovascular (CV) risk factors, the combined impact of COMISA is poorly defined. OBJECTIVE: This review aims to synthesize the available data on the association between COMISA and CV risk in adults, including closely related phenotypes (disturbed sleep in OSA patients). METHODS: A systematic search of PubMed and Web of Science databases was performed in October 2024. Included studies were published between 2015 and 2024 and examined the associations between OSA, insomnia, disturbed sleep and CV pathologies. RESULTS: Seventeen studies remained after rigorous selection. Limited studies suggest an association between COMISA and resistant hypertension or prevalent CV comorbidities. However, follow-up of large longitudinal cohorts shows no significant excess risk of incident CV events after adjustment for confounders. OSA patients with disturbed sleep do not appear to have an independent increased CV risk, in contrast to those with marked sleepiness. CONCLUSION: Although initial data suggest a potential synergistic effect of OSA and insomnia on CV risk, results remain mixed and limited by considerable methodological heterogeneity. Integrated management focusing on the multiple vulnerabilities of COMISA patients seems to be the most appropriate approach, regardless of a direct association with CV risk.