The relationship between secondary hyperparathyroidism and thyroid cancer in end stage renal disease: A population based cohort study

Objectives We conducted a retrospective cohort study to investigate the risk of cancer in end stage renal disease (ESRD) patients with secondary hyperparathyroidism (HPT). Patients and methods This study investigated the elevated overall cancer risk in ESRD patients with secondary HPT in Taiwan. We used a population-based retrospective cohort consisting of original claims data of 1 million beneficiaries randomly sampled from the Taiwan National Health Insurance Research Database (NHIRD). We calculated the hazard ratios (HRs) and 95% confidence intervals (CIs) of cancer in the ESRD with secondary HPT and comparison cohorts, using the Cox proportional hazards regression model. Results We observed that ESRD patients with secondary HPT exhibited a 10.1-fold increased risk of thyroid cancer than did ESRD patients without this parathyroid complication, after adjusting for comorbidities (95% confidence interval = 1.12-91.0). Conclusion These phenomena indicate that ESRD patients with secondary HPT are at greater risk of thyroid cancer. Physicians should be alert for occult thyroid cancer in ESRD patients with secondary HPT.