Key result
Adequate adherence to β-blockers (MPR ≥0.8) was observed in only 49% of patients with long QT syndrome types 1 and 2, with no identifiable clinical or demographic predictors of nonadherence.
Observational (n=90)
Adherence to life-saving β-blocker therapy in patients with long QT syndrome is suboptimal in approximately half of the population, highlighting a critical gap in clinical management.
Suboptimal β-blocker adherence affects half of LQTS1/2 patients; leaves open identification of risk factors and outcome effects.
BACKGROUND: Long-term uninterrupted β-blockade significantly reduces cardiac events in long QT syndrome (LQTS). Despite this, data on nonadherence are scarce and quantified only on the day of cardiac arrest in LQTS literature. We aimed to describe β-blocker adherence, and predictors thereof, among patients with LQTS types 1 and 2. METHODS AND RESULTS: Electronic health records and pharmacy dispensing data were reviewed for 90 patients with LQTS 1 and 2 who reside in Auckland, New Zealand, during a 34-month period. For each patient, the medication possession ratio (MPR: proportion of follow-up days patients were dispensed β-blocker) was calculated. Adequate adherence was characterized by an MPR ≥0.8 and ideal as MPR=1.0. Clinical and demographic features were assessed to determine whether they predicted adherence. Long-term β-blockers were prescribed to 74 patients (82%). Side effects were described as intolerable by 6 (8%) and their β-blockers were stopped. MPR was calculated in the remaining 68 patients >151.7 patient-years of follow-up. Median MPR was 0.79 (range, 0-1.3). Suboptimal adherence (MPR<0.8) was recorded in 35 (51%). Seven patients (10%) never took up a prescription (MPR=0). Adequate adherence was present in 33 (49%), including 9 (13%) who had ideal adherence. Age, sex, clinical presentation, family history of sudden death, ethnicity, and deprivation index did not predict adherence. CONCLUSIONS: Adherence to β-blockers in LQTS is suboptimal in half of those with LQTS 1 and 2. Risk factors for nonadherence could not be identified in our population. Further research into β-blocker adherence is imperative in this high-risk population.
No takes yet. Share an insight, caveat, or question.
Waddell-Smith et al. (2016) conducted an observational in Long QT syndrome types 1 and 2 (n=90). β-blocker therapy was evaluated on Adequate adherence (Medication Possession Ratio ≥0.8). Adequate adherence to β-blockers (MPR ≥0.8) was observed in only 49% of patients with long QT syndrome types 1 and 2, with no identifiable clinical or demographic predictors of nonadherence.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: