Association between demographic, organizational, clinical, and socio-economic characteristics and underutilization of cardiac resynchronization therapy: results from the Swedish Heart Failure Registry.
Cardiac resynchronization therapy (CRT) improves outcomes in heart failure (HF) but may be underutilized. The reasons are unknown.



We linked the Swedish Heart Failure Registry to national registries with ICD-10 (International Classification of Diseases-10th Revision) co-morbidity diagnoses and demographic and socio-economic data. In patients with EF ≤39% and NYHA II-IV, we assessed prevalence of CRT indication and CRT use. In those with CRT indication, we assessed the association between 37 potential baseline covariates and CRT non-use using multivariable generalized estimating equation (GEE) models. Of 12 807 patients (mean age 71 ± 12 years, 28% female), 841 (7%) had CRT, 3094 (24%) had an indication for but non-use of CRT, and 8872 (69%) had no indication. Important variables independently associated with CRT non-use were: HF duration <6 months [risk ratio (RR) 1.21, 95% confidence interval (CI) 1.17-1.24]; non-cardiology planned follow-up (RR 1.14, 95% CI 1.09-1.18); age >75 years (RR 1.13, 95% CI 1.09-1.18); non-cardiology care at baseline (RR 1.10, 95% CI 1.07-1.14); small-town non-university centre (RR 1.08, 95% CI 1.05-1.12); female sex (RR 1.07 95% CI 1.03-1.10) (all P < 0.05); as was absence of AF, living alone; psychiatric diagnosis; smoking; and non-use of HF drugs. Education, income, cancer, or HF characteristics were not independently associated with CRT non-use.



In this population-wide HF registry, CRT was underutilized. Non-use was associated mostly with demographic and organizational, but not clinical or socio-economic factors. This calls for programmes to raise awareness of CRT indications and improve access and referrals to cardiology specialists.
Karolinska Institutet, Department of Medicine, Stockholm, Sweden.|Karolinska University Hospital, Department of Cardiology, Stockholm, Sweden.
Lars H
LH
Lund
Karolinska Institutet, Department of Medicine, Stockholm, Sweden.|Karolinska University Hospital, Department of Cardiology, Stockholm, Sweden.
Frieder
F
Braunschweig
Karolinska Institutet, Department of Clinical Science and Education, South Hospital, Stockholm, Sweden.
Lina
L
Benson
Karolinska Institutet, Department of Medicine, Stockholm, Sweden.|Karolinska University Hospital, Department of Cardiology, Stockholm, Sweden.
Marcus
M
Ståhlberg
Department of Cardiology and Department of Medicine and Health Sciences, Linköping University, Linköping, Sweden.
Ulf
U
Dahlström
Karolinska Institutet, Department of Medicine, Stockholm, Sweden.|Karolinska University Hospital, Department of Cardiology, Stockholm, Sweden.
Cecilia
C
Linde
D000368:Aged; D000369:Aged, 80 and over; D058406:Cardiac Resynchronization Therapy / Q000706:statistics & numerical data*; D003710:Demography; D005260:Female; D006333:Heart Failure / Q000453:epidemiology* / Q000628:therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012042:Registries; D012959:Socioeconomic Factors; D013548:Sweden / Q000453:epidemiology; D016896:Treatment Outcome
Cardiac resynchronization therapy; Epidemiology; Guidelines; Heart failure; Implementation; Utilization