Clinical characteristics and burden of non-obstructive hypertrophic cardiomyopathy: a real-world survey in Italy and Spain
Authors: Lowe M , Jackson J , Zhong Y , Contente M , Le Brocq L , Barlow S , Krause T 
Published: October 2024

Abstract

Background
Research describing non-obstructive hypertrophic cardiomyopathy (nHCM) and the associated burden of illness is sparse.

Purpose
This research aimed to describe the clinical characteristics of patients with nHCM and the associated clinical and societal burden of illness in Italy (IT) and Spain (ES).

Methods
Data were from the Adelphi HCM Disease Specific Programme (DSP), a cross-sectional survey with retrospective data collection in IT and ES (July 2022–January 2023). Ethics approval was obtained from the Pearl Institutional Review Board. Cardiologists provided data on patient demographics, employment, clinical characteristics, symptoms, support needs and treatment for up to ten consecutively consulting adult HCM patients. Patients voluntarily completed a survey containing the Kansas City Cardiomyopathy Questionnaire-23 (KCCQ). Analyses were descriptive and the mean [SD] was summarized for continuous variables.

Results
Overall, 112 cardiologists provided data for 483 patients with nHCM from IT (243) and ES (240). The mean age [SD] was 54.3 [14.1] and 58.0 [16.0], with 66.3% and 61.7% of patients being male, in IT and ES respectively. Eighty-four percent and 92.1% of patients were classified as New York Heart Association (NYHA) II, 14.8% and 7.1% were NYHA III, and 1.2% and 0.8% were NYHA IV, in IT and ES respectively. Among patients who completed the KCCQ, the mean [SD] KCCQ-clinical summary score was 84.9 [12.9] in IT and 81.8 [20.7] in ES. Regarding work-related impact, 30.8% (IT) and 16.7% (ES) of patients had taken time off work due to nHCM in the last three months, and 41.6% (IT) and 48.4% (ES) were not working full-time, of which 5.6% (IT) and 11.0% (ES) were not working full time due to nHCM. Additionally, 17.6% and 18.2% of patients experienced a delayed diagnosis in IT and ES respectively, with 24.0% (IT) and 25.0% (ES) having multiple delays to diagnosis. The most common symptoms reported by physicians were dyspnoea when active (83.7%), palpitations (29.3%) and fatigue (25.7%). The most prevalent concomitant conditions were hypertension (20.5%), anxiety (18.6%), and atrial fibrillation (18.4%). In IT and ES, respectively, 77.8% and 74.2% of patients were currently prescribed treatment for nHCM. The most frequently prescribed treatments were beta-blockers (83.3%), diuretics (32.1%) and angiotensin converting enzyme inhibitors (20.5%), alone or in combination. In IT and ES respectively, 14.4% and 18.8% of patients required caregiver support, at a mean [SD] of 46.3 [52.4] and 44.2 [47.5] hours per week.

Conclusions
While the majority of patients with nHCM were classified as NYHA II, a considerable clinical and societal burden is evident. Burden was demonstrated by the high prevalence of symptoms, comorbidities, disruptions to employment and the requirement for caregiver support among these patients, highlighting the need for new treatment and management approaches to enhance health outcomes and reduce societal impact.