Hypertrophic cardiomyopathy increased all-cause death risk compared to matched controls (HR 1.35; 95% CI 1.27-1.44), although mortality decreased by approximately 50% over 20 years.
Cohort (n=12,288)
Yes
Does the prognosis of hypertrophic cardiomyopathy (HCM) differ from matched controls, and how have morbidity and mortality rates changed between 2003 and 2022?
Over two decades, mortality in HCM has decreased by approximately 50%, though patients still face significantly higher risks of death, heart failure, and stroke compared to the general population.
Effect estimate: HR 1.35 (95% CI 1.27-1.44)
Abstract Background/Introduction Hypertrophic cardiomyopathy (HCM) is a myocardial disease with variable course, from subclinical to fatal. Previous studies have reported improved prognosis over the last decades, but long-term studies in Sweden are lacking. Purpose To evaluate the trends of morbidity and mortality in HCM during the years 2003 to 2022. Methods Data regarding medical diagnoses, hospitalisations, and cause of death from the Swedish National Cause of Death Register and the Swedish National Patient Register, for the study period were analysed. The registers include all patients ≥ 17 years of age diagnosed with HCM in both in-hospital and in out-patient specialised care in Sweden. Patients were categorised based on a first ever ICD 10-diagnostic code for HCM with (I42.1, OHCM) or without (I42.2, nonOHCM) LVOTO. The age- and sex adjusted incidence rates per study year for all-cause death, sudden cardiac death (SCD), heart failure (HF) and new-onset stroke/transient ischaemic attack (TIA) were analysed. The risk for each variable, adjusted for age, sex, hypertension, diabetes, and ischaemic heart disease, were calculated for HCM, OHCM and nonOHCM, vs five age- and sex matched controls for every patient, randomly selected from the Swedish longitudinal integrated database for health insurance and labour market studies. Results Data for 12,288 patients (median age 68.0 17.0–100.0 years, 58% male, 33% OHCM) were analyzed.In OHCM, patients were significantly older (66.2 years vs 64.6 years), less often male (49.6% vs 61.4% men), than in nonOHCM. In HCM, all-cause mortality decreased from 10.5% to 4.8% (yearly event rate 6.4% over a median follow-up (FU) of 4.8 y), SCD from 1.1% to 0.7% (0.5%, FU 8.0 y), HF hospitalisations from 9.4% to 3.7% (4.4%, FU 5.1 y), and stroke/TIA from 2.0% to 1.2% (0.7%, FU 7.8 y), incidence rates per group in Fig. 1. Compared to controls, HCM increased the risk for all-cause death hazard ratio (HR) 1.35 (95% CI 1.27-1.44), SCD HR 1.31 (95% CI 1.08-1.58), HF hospitalization HR 3.28 (95% CI 3.01-3.57) and stroke/TIA HR 1.93 (95% CI 1.66 - 2.24). Results per group vs controls in Fig.2. Compared to OHCM, the risk for stroke/TIA was significantly lower in nonOHCM, but higher for the other outcomes. Conclusions Although still entailing substantial risks, the prognosis for patients with clinical HCM has improved markedly, with an approximately 50% reduction in mortality over 20 years. In contrast to several previous studies, the prognosis was not worse for OHCM than for nonOHCM.
Silverdal et al. (Sat,) conducted a cohort in Hypertrophic cardiomyopathy (n=12,288). Hypertrophic cardiomyopathy vs. Age- and sex-matched controls was evaluated on All-cause death (HR 1.35, 95% CI 1.27-1.44). Hypertrophic cardiomyopathy increased all-cause death risk compared to matched controls (HR 1.35; 95% CI 1.27-1.44), although mortality decreased by approximately 50% over 20 years.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: