Evaluating Snoring as a Cardiovascular Risk Factor: Myocardial Infarction, Stroke, and mortality in a 28-Year Study of 971 Middle-Aged Swedish Men in the Automotive industry

Background Cardiovascular disease (CVD) remains the leading cause of mortality worldwide, responsible for 32% of all deaths globally in 2019 and 29% of deaths in Sweden in 2023. Since the Framingham study began in 1942, numerous risk factors for CVD have been identified. Recently, interest has surged regarding the relationship between sleep-related breathing disorders and CVD, particularly concerning obstructive sleep-related apnea syndrome (OSAS), which is associated with an increased risk of hypertension, diabetes, myocardial infarction (MI), stroke, and dementia. However, research on snoring and the association with CVD remains inconclusive. This study aims to investigate the association between snoring and CVD, examining whether this association persists after adjusting for potential confounding factors, and to determine if snoring in men at ages 45-50 can serve as predictor of future cardiovascular outcomes. Results : In 1993, data on snoring were collected from 971 of addressed 1 000 men employed in automotive companies in Sweden who participated in a nurse-led health examination, which included completing a questionnaire and undergoing blood work at their workplace. In 2024, incidents of first-time myocardial infarctions, strokes, and deaths were identified using three national registries in Sweden. Statistical analyses were conducted to calculate odds ratios (OR) for snoring in relation to cardiovascular outcomes, perform multivariate analysis to identify potential confounders, and conduct survival analysis to assess the time to cardiovascular events. Habitual snorers exhibited higher levels of blood pressure, lipids, glucose and body mass index alongside increased rates of smoking and alcohol consumption compared to non-snorers or occasional snorers. The odds of cardiovascular mortality were 2.2 times (p=0.03) greater for snorers than for non-snorers and occasional snorers. Nevertheless, no statistical significance was observed in the multivariate analysis or the survival analyses regarding snoring. Conclusions : Habitual snorers demonstrate an increased likelihood of cardiovascular death compared to non-snorers and occasional snorers; however, the relationships between snoring and stroke, MI, and all-cause mortality remain unclear. Therefore, snoring cannot currently be classified as an independent risk factor for CVD, necessitating further investigation. Key words: snoring, myocardial infarction, stroke, mortality, cohort study, Swedish men