Parathyroidectomy slows renal function decline in patients with primary hyperparathyroidism

Primary hyperparathyroidism has deleterious effects on health and causes nephrolithiasis and osteoporosis. However, it remains unclear whether parathyroidectomy benefits kidney function among patients with primary hyperparathyroidism.

In this retrospective study, patients with primary hyperparathyroidism receiving parathyroidectomy in a tertiary medical center between 2003 and 2017 were followed up until December 31 2017, death, or requiring renal replacement therapy. Impact of parathyroidectomy on kidney function was examined using longitudinal estimated glomerular filtration rate (eGFR) change scales: single, average, absolute difference, percent change, annual decline rate, and slope. We applied linear mixed-effect model to determine the effect of parathyroidectomy on kidney function.

During study period, 167 patients with primary hyperparathyroidism were identified from 498 parathyroidectomized patients, and finally, 27 patients fulfilled our stringent criteria. Median follow-up duration was 1.50 years (interquartile range 1.05-1.81) before surgery and 2.47 years (1.37-6.43) after surgery. Although parathyroidectomy did not affect amount of proteinuria and distribution of eGFR, parathyroidectomy significantly slowed decline rate of eGFR compared with that before surgery (- 1.67 versus - 2.73 mL/min/1.73 m²/year, p < 0.001). More importantly, parathyroidectomy made more beneficial effects on kidney function in patients with age < 65 years and those without chronic kidney disease or hypertension.

Our study showed that parathyroidectomy slows renal function decline irrespective of age or comorbidities, which offers novel insight into the revision of guidelines for surgical indications in primary hyperparathyroidism. Given small sample size, further large-scale controlled studies are warranted to confirm our findings.