Adherence to heart failure therapy influences LV recovery in women with PPCM
Authors: Hoevelmann J , Viljoen C A , Maalouli Schaar J , Boehm M , Meyer M R , Sliwa K 
Published: November 2023

Abstract

Introduction
Peripartum cardiomyopathy (PPCM) is characterised by left ventricular (LV) dilatation and dysfunction developing towards the end of pregnancy or in the first months postpartum. Although about 60% of women with PPCM, the majority on evidence based (EBM) heart failure medications, show LV recovery within six to twelve months, others remain with persistently impaired LV function. Poor adherence to EBM represents a major cause of avoidable hospitalizations, disability and death in other cardiovascular conditions.

Purpose
We aimed to study drug adherence to heart failure (HF) therapy of women with PPCM and to identify possible associations between drug adherence and LV recovery, functional status and psychosocial factors.

Methods
In this prospective, observational study, we included 36 consecutive women with PPCM, who returned for their regular follow-up visit. Adherence to HF treatment was assessed by self-reported adherence, pharmacy refills of HF drugs [ACE-i/ARB, BB, MRA] and drug levels by means of liquid chromatography high-resolution mass spectrometry (LC-HRMS) of plasma. Participants were classified as following: "adherent" (all prescribed HF drugs were detectable by LC-HRMS), "partially adherent" (at least one prescribed drug detectable) and "non-adherent" (none of the prescribed drugs were detectable). Health state index scores were assessed by EQ5D including mobility, self-care, usual activities, pain/discomfort, and anxiety/depression.

Results
Patients’ median age was 32.4 years (IQR 27.6-36.1) with a median time of 16 months (IQR 5-45) between the first presentation and the adherence visit. Prescription at the adherence visit included 77.8% BB, 75% ACE-i/ARB, 47.2% MRA and 95.2% loop diuretics. The median LVEF at follow-up was 46% (IQR 34-55). Self-reported adherence was 50% and 66.7% of patients collected all pharmacy refills in 6 months prior to follow-up. According to LC-HRMS, 23.5% participants were classified as adherent, 53% as partially adherent, and 23.5% as non-adherent. Adherent patients showed significantly lower LVEDD at follow-up (47 mm [IQR 46-52), vs 56 mm [IQR 49-64] in partially adherent, and 62 mm [IQR 55-64] in non-adherent, p=0.022) and had a higher LVEF at follow up (60% [IQR 41-65]), vs partially adherent (46% [IQR 34-50]) and non-adherent patients (41% [IQR 29-47], p=014). Adherent patients had a lower overall EQ5D score (5.5 [IQR 5-7.5], vs 6 [IQR 5-7] in partially adherent, and 10 [IQR 8-15] non-adherent patients, p=0.032) suggestive of a better self-rated health status (Figure 1).

Conclusion
For the first time, we show that drug adherence in PPCM is sub-optimal. High adherence to HF therapy was associated with favourable LV remodeling. A better self-rated health status was associated with adherence. Our study highlights the importance of drug adherence for functional recovery in PPCM. Drug adherence should be an important component of patient communication and specific interventions in PPCM.Figure 1