High societal costs and reduced health-related quality of life in inflammatory and systemic immune disease-associated dilated cardiomyopathies

Background: Dilated cardiomyopathy (DCM) comes with an estimated societal cost of above €10,000 per patient per year and a lower quality of life (QoL). However, DCM represents a heterogeneous disease with different aetiologies that can be combined in subgroups. Insight in QoL and societal costs per DCM subgroup may guide resource allocation, research focus areas, and tailored patient management. We investigated subgroup-specific costs and QoL in patients with DCM. Methods: Patients with DCM (n = 550) were included, all phenotyped by endomyocardial biopsy and genetic testing besides routine cardiac evaluation. Patients were classified as chemotherapy-induced DCM (n = 27), genetic DCM (n = 91), inflammatory DCM (n = 53), systemic immune-mediated disease (SID)-associated DCM (n = 83), alcohol-induced DCM (n = 40), and idiopathic DCM (n = 280). QoL and societal costs were cross-sectionally evaluated using the EQ-5D-5 L and the iMTA medical and productivity cost questionnaires, sent at 8 [IQR 5; 12] years after cardiomyopathy diagnosis. Results: Compared to other subgroups, QoL was lower for inflammatory DCM (-0.053 [-0.106; -0.003], p = 0.04), SID-associated DCM (-0.078 [-0.126; -0.031], p < 0.01), and alcohol-induced DCM (-0.079 [-0.141; -0.017], p = 0.01). Societal costs were higher for patients with inflammatory DCM (19,197€ [13,703 − 27,211]; log-transformed change + 0.862 [0.103; 1.621], p = 0.03), and SID-associated DCM (19,197€ [8,494 − 25,623]; log-transformed change + 0.804 {0.104; 1.505], p = 0.03). Healthcare costs were highest for patients with inflammatory DCM (6,198€ [4,083 − 8,626], log-transformed change + 0.614 [0.039; 1.189] p = 0.049). Conclusion: Patients with DCM due to chronic myocarditis or a SID have lower QoL and higher societal costs due to higher healthcare costs, compared to patients with DCM and other etiologies. These findings may guide resource allocation, research focus areas, and tailored management such as patient education, financial counseling, and psychological support.