Obstructive Sleep Apnoea and Cardiovascular Comorbidity: A Narrative Review with Implications for Clinical Practice in Sub-Saharan Africa

ABSTRACT Background Obstructive sleep apnoea (OSA) is a highly prevalent but significantly underdiagnosed sleep disorder characterised by repetitive episodes of upper airway collapse during sleep, resulting in intermittent hypoxia, sympathetic activation, and systemic inflammation. Accumulating evidence implicates OSA as an independent risk factor for a spectrum of cardiovascular diseases (CVD) including hypertension, heart failure, cardiac arrhythmias, and coronary artery disease. Despite this established association, OSA remains largely unrecognised as a modifiable cardiovascular risk factor in clinical practice, particularly in Sub-Saharan African settings where diagnostic infrastructure is limited and cardiovascular disease burden is rising. This review synthesises current evidence on the pathophysiological mechanisms linking OSA to cardiovascular comorbidity and examines the implications for diagnosis and clinical management in resource-limited African contexts. Methods A narrative review of peer-reviewed literature was conducted using PubMed, Google Scholar, and African Journals Online (AJOL). Search terms included "obstructive sleep apnoea," "cardiovascular disease," "hypertension," "heart failure," "cardiac arrhythmia," "Sub-Saharan Africa," and "sleep-disordered breathing." Publications from 2000 to 2024 were prioritised, with seminal earlier studies included where relevant. A total of 27 sources were reviewed and synthesised thematically. Results OSA exerts cardiovascular harm through three principal pathophysiological pathways: intermittent hypoxia-driven oxidative stress, heightened sympathetic nervous system activity, and systemic vascular inflammation. These mechanisms collectively drive the development and progression of hypertension, heart failure, cardiac arrhythmias, and atherosclerotic disease. Evidence consistently demonstrates that untreated OSA significantly worsens cardiovascular outcomes, while continuous positive airway pressure (CPAP) therapy reduces cardiovascular risk. In Sub-Saharan Africa, rising obesity rates, hypertension prevalence, and limited polysomnographic diagnostic capacity create a critical but poorly characterised OSA-CVD burden requiring urgent clinical attention. Conclusion Obstructive sleep apnoea represents a treatable yet widely overlooked contributor to cardiovascular morbidity and mortality. Strengthening OSA awareness, screening, and management within African healthcare systems is essential to reducing the compounding burden of cardiovascular disease across the region.