Age and Sex Differences in the Risk of Sudden Cardiac Death in Patients with Hypertrophic Cardiomyopathy: A Multi-Centre Cohort Study

Huihui Ma,1,2 Fengcheng Xu,3,4 Lei Liu,5 Caixia Pan,1,2 Rong Luo,6 Mingjiang Liu,1,2 Tianhu Liu,3 Yan Shu,1,2 Xiaoping Li1,2 1School of Medicine, University of Electronic Science and Technology of China, Institute of Cardiovascular Diseases & Department of Cardiology, Sichuan Provincial People’s Hospital, Chengdu, 610072, People’s Republic of China; 2Chinese Academy of Sciences Sichuan Translational Medicine Research Hospital, Chengdu, 610072, People’s Republic of China; 3Department of Cardiology, Pidu District People’s Hospital, Chengdu, Sichuan, 611730, People’s Republic of China; 4Cardiology and Vascular Health Research Center, Chengdu Medical College, Chengdu, Sichuan, 610500, People’s Republic of China; 5Department of cardiology, Suining Central Hospital, Suning, Sichuan, 629000, People’s Republic of China; 6Institute of Geriatric Cardiovascular Disease, Chengdu Medical College, Chengdu, Sichuan, 610500, People’s Republic of ChinaCorrespondence: Xiaoping Li, Institute of Cardiovascular Diseases & Department of Cardiology, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, 610072, People’s Republic of China, Email [email protected] Yan Shu, Institute of Cardiovascular Diseases & Department of Cardiology, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, 610072, People’s Republic of China, Email [email protected]: There is a significant difference in prognosis among patients with hypertrophic cardiomyopathy (HCM) across different age groups and gender groups. This study aims to explore the risk of sudden cardiac death (SCD) in various age groups and genders.Methods: A cohort of 2781 patients with HCM, initially evaluated between 1996 and 2023, were followed for a median of 4.54 years. The patients were divided into three age groups: youth group (aged ≤ 40 years), middle-aged group (aged between 40 and 60 years), and elderly group (aged ≥ 60 years). The outcome event was (SCD). Kaplan-Meier survival curves and Cox regression analysis were employed to compare outcomes across different age groups for both genders. Additionally, restricted cubic splines (RCS) were utilized to evaluate the potential relationship between age and prognosis within different gender categories.Results: A total of 128 patients (4.6%) experienced SCD. In the whole population, significant age differences were observed in the Kaplan-Meier survival curves for SCD (log-rank P< 0.0001). Significant age differences in SCD were also noted in both genders (log-rank P< 0.0001). In multivariate Cox regression analysis, age was an independent predictor of SCD in the whole population [HR: 0.983; 95% CI: 0.972– 0.994; P=0.003] and female patients [HR: 0.963; 95% CI: 0.947– 0.98; P< 0.001]. However, it was not significant in male patients [HR: 0.995; 95% CI: 0.98– 1.01; P=0.538].Conclusion: In patients with HCM, age was an independent predictor of SCD both the whole population and female patients. Compared to young patients, the risk of SCD is reduced by 71.4% in middle-aged patients and by 43.5% in elderly patients across the whole population. Among male patients, the risk of SCD decreases by 68.5% in middle-aged patients and by 10.7% in elderly patients. In female patients, the risk of SCD is reduced by 77.8% in middle-aged patients and by 75.3% in elderly patients.Keywords: hypertrophic cardiomyopathy, sudden cardiac death, restricted cubic splines