Prevalence of anti-beta-1 antibody 6 months after hospitalization for acute heart failure predicts adverse outcome.

Abstract

Agonistic antibodies against neurohumoral receptors can induce cardio-noxious effects by altering the baseline receptor activity. To estimate the prevalence of autoantibodies directed against the beta-1 receptor (b1-AAB) in patients admitted to the hospital for acute heart failure (HF) at (i) baseline and (ii) after 6months of follow-up (F6) and (iii) after another 12months of follow-up (i.e. 18months after index hospitalization), to estimate their prognostic impact on clinical outcome (death or first hospitalization for HF). In 47 patients, b1-AAB were serially determined in serum samples collected at index hospitalization and at 6months of follow-up (F6) with a flow cytometry-based assay: median age 71years (quartiles 60, 80), 23 (49%) women, 24 (51%) HF with preserved ejection fraction. Beta1-AAB were detected in three subjects at index hospitalization (6%), and in eight subjects at F6 (17%). There were no differences apparent between patients with and without b1-AAB at F6 with regard to age, sex, type, duration, or main cause of HF. During the 12month period following F6 (i.e. up to month 18), eight events occurred. Event-free survival was associated with prevalence of b1-AAB at F6. Compared with patients without b1-AAB at F6, age-adjusted Cox regression indicated a higher event risk in patients harbouring b1-AAB, with a hazard ratio of 8.96 (95% confidence interval 1.81-44.50, P=0.007). Our results suggest a possible adverse prognostic relevance of b1-AAB in patients with acute HF, but this observation needs to be confirmed in larger patient collectives.