Increased resting heart rate and prognosis in treatment-naïve unselected cancer patients: results from a prospective observational study

Abstract

Aims: Cancer patients suffer from impaired cardiovascular function. Elevated resting heart rate (RHR) has been identified as a marker for increased long-term mortality in cancer patients prior to the receipt of anticancer treatment. We aimed to establish whether RHR is associated with survival in treatment-naïve cancer patients. Methods and results: This prospective study enrolled 548 unselected treatment-naïve cancer patients between 2011 and 2013. The median age of the cohort was 62 years; 40.9% were male and 32.7% had metastatic disease. Median RHR was 72 b.p.m. Most patients were in sinus rhythm (n = 507, 92.5%). Clinical heart failure was noted in 37 (6.8%) patients. RHR was not related to cancer stage (P = 0.504). Patients in the highest RHR tertile had higher levels of high-sensitivity troponin (P = 0.003) and N-terminal pro-B-type natriuretic peptide (P = 0.039). During a median follow-up of 25 months (interquartile range: 16–32 months; range: 0–40 months), 185 (33.8%) patients died from any cause [1-year-mortality: 17%, 95% confidence interval (CI) 13–20%]. In univariate survival analysis, RHR predicted all-cause mortality [crude hazard ratio (HR) for a 5 b.p.m. increase in RHR: 1.09, 95% CI 1.04–1.15; P < 0.001], and remained significantly associated with outcome after adjustment for age, gender, tumour entity, tumour stage, cardiac status and haemoglobin (adjusted HR for a 5 b.p.m. increase in RHR: 1.10, 95% CI 1.04–1.16; P < 0.001). There was no significant impact of metastatic/non-metastatic disease state on the predictive value of RHR (P = 0.433 for interaction). In subgroup analyses, the strongest associations for RHR with mortality were observed in lung (crude HR 1.14; P = 0.007) and gastrointestinal (crude HR 1.31; P < 0.001) cancer. Conclusions: Treatment-naïve cancer patients with higher RHRs display higher levels of cardiovascular biomarkers. RHR was independently associated with all-cause mortality, especially in lung and gastrointestinal cancers. Elevated RHR and cardiovascular biomarkers may represent early signs of incipient cardiac dysfunction.