Non-psychotic mental disorders in adolescent men and risk of myocardial infarction: a national cohort study

Abstract

Abstract Background/Purpose Recent studies show that early life stress is associated with later risk of cardiovascular disease (CVD) and stress may also increase the risk of psychiatric disease. We investigated the association between non-psychotic mental disorders in adolescence and subsequent myocardial infarction, and the role of stress resilience and physical fitness in this association. Method This is a register-based cohort study with 238 013 males born between 1952 and 1956 followed from 1987 to 2010 using information from Swedish registers. Stress resilience was measured at a compulsory military conscription examination using a semi-structured interview with a psychologist. Physical fitness was measured at conscription examination with a cycle ergometer test. A total of 34 503 men were diagnosed with a non-psychotic mental disorder at conscription. Using Cox regression, we estimated the association of mental disorders with myocardial infarction after adjustment for other established CVD risk factors in adolescence. Stress resilience and physical fitness were included in the adjusted model in a second set of analyses. Results A total of 5891 diagnoses of first myocardial infarction were identified. Non-psychotic mental disorders were associated with an increased risk of myocardial infarction, with a hazard ratio (HR) and confidence interval (CI) of 1.51 (1.41–1.62). The association remained statistically significant after adjustment for other important potential confounders in adolescence such as systolic and diastolic blood pressure, body mass index, inflammation, cognitive function, parental socioeconomic index and a summary disease score (HR 1.24 (CI 1.13–1.35)). The association was further explained by stress resilience and lifestyle factors assessed with a cardiovascular fitness test in adolescence, as the association attenuated but remained statistically significant when further adjusting for stress resilience and physical fitness (HR 1.18 (CI 1.08–1.29)). Conclusion A non-psychotic mental disorder in adolescences may increase the risk of developing myocardial infarction later in life. This association was partly but not completely explained by poorer stress resilience and physical fitness. Effective prevention might focus on behaviour/lifestyle and psychosocial stress in early life. Funding Acknowledgement Type of funding source: None