The Association Between Schizophrenia and Cardiovascular Diseases: A Retrospective Cohort Study of Primary Care Routine Data in Germany.

Background: This novel study addresses the question of whether schizophrenia is associated with an increased risk of cardiovascular diseases (CVDs) by controlling for metabolic syndrome-related conditions through propensity score matching, using real-world primary care data from Germany. Methods: This retrospective cohort study analyzed 12,527 patients aged 18 or older with schizophrenia from 1209 general practices (GPs) in Germany between 2005 and 2023 from the IQVIA Disease Analyzer database. Patients were matched 1:5 with individuals without schizophrenia based on sex, age, index year, consultation frequency, and chronic conditions. CVDs cumulative incidence was assessed using Kaplan-Meier curves and hazard ratios (HRs) were calculated using univariable Cox regression analysis. Results: Over a 10-year follow-up, schizophrenia was associated with a higher risk of heart failure (HR: 1.33, 95% CI: 1.20-1.48) and a lower risk of atrial fibrillation and flutter (HR: 0.77, 95% CI: 0.67-0.89). No significant associations were observed for acute myocardial infarction (HR: 0.97, 95% CI: 0.76-1.25), angina pectoris (HR: 0.78, 95% CI: 0.63-0.96), or chronic ischaemic heart disease (HR: 0.91, 95% CI: 0.82-1.02). Stratified analyses showed that schizophrenia was most strongly associated with heart failure in women aged 41-50 years (HR: 3.34, 95% CI: 2.11-5.31), followed by women aged 61-70 years (HR: 1.88, 95% CI: 1.45-2.44) and men aged 51-60 years (HR: 1.81, 95% CI: 1.34-2.45). Conclusions: This study highlights significant differences in the 10-year cumulative incidence of CVDs between individuals with and without schizophrenia. While patients with schizophrenia appear less likely to be diagnosed with milder or asymptomatic CVDs, they are at increased risk for severe outcomes. The study's findings underscore the need for sex-specific and symptom-sensitive public health strategies to improve early detection and prevention of CVDs in patients with schizophrenia.