Impact of guideline-directed medical therapies on clinical and economic outcomes in nonobstructive hypertrophic cardiomyopathy: analysis of data from a multinational cross-sectional survey
P Gebrehiwet, J Jackson, L Hargreaves, S Barlow, L Lebrocq, J Brekke, M Butzner, S Shreay, P DivanjiAbstract
Background
There are no approved therapies for nonobstructive hypertrophic cardiomyopathy (nHCM). The current guideline-directed medical therapy (GDMT) focus is on beta-blockers, calcium channel blockers, or disopyramide and that current guidelines simply draw recommendations from obstructive HCM due to lack of evidence in nHCM. The impact of GDMT on clinical and economic outcomes in nHCM remains unclear.
Objective
To characterize and compare the clinical and economic outcomes of patients with nHCM currently receiving unapproved treatment following guideline recommendations (guideline-treated) vs those who did not (non–guideline-treated).
Methods
Data were drawn from the Adelphi Real World HCM Disease Specific Programme (DSP™), a multinational, cross-sectional survey conducted between July 2022 and October 2024 in Italy, Spain, and the United States. Clinical outcomes, including symptoms and cardiovascular (CV) comorbidities, were collected. Healthcare resource utilization (HCRU; ie, hospitalizations, emergency room [ER] visits, day visits, caregiver support) and quality of life (QoL) assessed by EQ-5D-5L and EQ-VAS were measured. Means were reported for utilization and QoL; symptoms and comorbidities with prevalence >5% were summarized as percentages. GDMT was defined as patients who received ≥1 of the following treatments: a non-vasodilating beta-blocker (metoprolol, bisoprolol, propranolol, atenolol, or nadolol), a non-dihydropyridine calcium channel blocker (verapamil or diltiazem), or disopyramide. Outcomes were compared between patients who received GDMT and those who did not.
Results
Of 723 patients (mean age, 55.11 years; 61.41% were male), 70.40% received GDMT for nHCM, with a mean duration of 1.93 years (Table 1). GDMT-treated patients had a significantly higher rate of dyspnea on activity, fatigue/weakness, and chest pain on activity (P<0.05 for all) compared with untreated patients. CV comorbidities, including hypertension, atrial fibrillation/atrial flutter, and heart failure (P<0.05 for all), were also more prevalent in GDMT-treated vs untreated patients. HCRU was higher among GDMT-treated patients, with more HCM-related ER visits and day visits (P<0.05 for both). Furthermore, patients receiving GDMT reported lower QoL, as measured by EQ-5D-5L and EQ-VAS scores (P>0.05 for both) (Table 2).
Conclusions
Two-thirds of patients with nHCM received GDMT. Despite the high proportion of nHCM patients treated with GDMT, patients continued to experience substantial clinical and economic burden when compared with those not treated according to guideline recommendations. These findings highlight the urgent need for novel therapies that address the underlying disease mechanisms of nHCM to reduce symptoms and improve QoL.For image description, please refer to the figure legend and surrounding text.For image description, please refer to the figure legend and surrounding text.