Age-dependent associations with the risk of mental disorders in patients with myocardial infarction: a UK Biobank cohort study

Abstract Background Despite an overall decrease in cardiovascular mortality in recent decades due to effective preventive strategies, a concerning trend is emerging among young adults, with a rising incidence of myocardial infarction (MI) and its poor prognosis. Previous studies report that a significant association between mental disorders and the incidence and prognosis of MI. However, a detailed age-specific information is still lacking. Purpose We aimed to determine whether the risk of developing mental disorders after MI differs based on age and to stratify individuals at a higher risk. Methods From the UK Biobank prospective database (n=502,386), we collected data on patients with a prior MI (n=10,840) and compared them to age- and sex-matched controls (n=54,197) in a 1:5 ratio. Diagnoses of mental disorders were ascertained through linked hospital admission and mortality data, using the appropriate ICD-10-CM codes. Mental disorders were defined by at least two inpatient or outpatient claims within 1 year. The primary outcome was a composite of incident mental disorders, including depression, anxiety, stress-related, and somatoform disorders. Follow-up was done until the first diagnosis of mental disorders or the end of 2022. Results During a median follow-up of 13.7 years (interquartile range 12.8-14.5 years), the incidence rate of the primary outcome was 9.28 vs. 5.37/1,000 person-years among patients with MI and controls, respectively (p<0.001). A prior MI history demonstrated an independent association with the risk of incident mental disorders, yielding an adjusted hazard ratio (aHR) of 1.41 (95% confidence interval [CI], 1.29–1.54; p<0.001) after adjusting for confounders. This was comparable to heavy drinking and family history of depression. Notably, the risk of mental disorders attributed to previous MI was more prominent in younger individuals aged <55 years than their older counterpart (aHR 1.61 vs. 1.33) (p-for-interaction 0.020). Similar results were observed in the analysis of two important components: depression and anxiety disorder. Furthermore, in younger patients with MI (<55 years), mental disorders significantly increased the risk of mortality, while not in older patients. Conclusion MI was associated with a higher risk of incident mental disorders, resulting in poor prognosis, particularly in young individuals. Active surveillance and prevention for incident mental disorders after young MI may be beneficial.Cumulative Incidence of Mental Disorders