Prospective cohort study of C-reactive protein as a predictor of clinical events in adults with congenital heart disease: results of the Boston adult congenital heart disease biobank.

Aims: Despite the well-defined association of high-sensitivity hsCRP with cardiovascular outcomes in apparently healthy adults and those with acquired heart disease, the relevance of this inflammatory marker in adults with congenital heart disease (ACHD) remains unclear. We aimed to examine the clinical correlates and prognostic value of high-sensitivity C-reactive protein levels in ACHD.

Methods and results: We conducted a prospective cohort study of (n = 707) outpatient ACHD (age 39 ± 14 years, 49% women), enrolled mainly at a referral centre, who had serum hsCRP measured in conjunction with a clinical assessment between 2012 and 2016. We analysed clinical correlates of hsCRP and its association with adverse events including the primary combined outcome of all-cause mortality or non-elective cardiovascular hospitalization. Higher hsCRP was strongly associated with measures of functional status including New York Heart Association class and peak V̇O2, and with comorbidities such as atrial arrhythmia. During average follow-up of 815 ± 536 days, 114 patients (16%) experienced the primary outcome, including 29 deaths. Having elevated hsCRP, in the highest (≥2.98 mg/L) compared with the lower three quartiles, conferred increased risk for the primary outcome [30.5% vs. 11.3%, adjusted hazard ratio (HR) = 2.00, 95% confidence interval (CI) 1.35-2.97; P = 0.0006] and all-cause mortality (11.9% vs. 1.5%, adjusted HR = 4.23, 95% CI 1.87-9.59; P = 0.0006). Elevated hsCRP was associated with adverse outcomes across ACHD subgroups and other patient characteristics.

Conclusion: Adults with congenital heart disease with elevated hsCRP have not only worse functional status and exercise capacity, but also greater risk for death or non-elective cardiovascular hospitalization. Further study is warranted to characterize the role of inflammation in the pathophysiology of ACHD.