In patients with chronic kidney disease (CKD) not on dialysis, elevated parathyroid hormone (PTH) levels correlate with an increased risk for fractures, vascular events, and death, Karen Hansen, MD, of the University of Wisconsin in Madison, and colleagues reported in Osteoporosis International.
Of 5108 patients with stage 3 to 4 CKD (mean age 68 years; 48% male) receiving care from Marshfield Clinic Health System during 1985 to 2013, fractures, vascular events, and death occurred in 18%, 71%, and 56%, respectively. PTH independently predicted each event in multivariate models. The lowest risks for these outcomes were associated with baseline PTH levels of 0, 69, and 58 pg/mL, respectively. The investigators adjusted models for age, gender, tobacco use, diabetes, hypertension, hyperlipidemia, vascular disease, obesity, estimated glomerular filtration rate, and osteoporosis medications. For consistency, only PTH measurements from second-generation assays were used.
The 2017 National Kidney Foundation guidelines did not specify PTH targets for patients with stage 3 to 4 CKD, so the investigators of the current study urged additional research to corroborate the target PTH range if feasible, followed by randomized placebo-controlled trials of PTH-lowering therapies.
“Doctors do not know whether treatment of high parathyroid hormone levels is linked to better outcomes in their patients with kidney disease,” Dr Hansen and the team stated.
In 2 studies of the Chronic Renal Insufficiency cohort involving 4000 CKD patients, baseline fibroblast growth factor 23 (FGF23) more strongly predicted vascular events and death. The current study did not assess FGF23, which limits interpretation of the findings.
Geng S, Kuang Z, Peissig PL, et al. Parathyroid hormone independently predicts fracture, vascular events, and death in patients with stage 3 and 4 chronic kidney disease. Osteoporos Int. doi:10.1007/s00198-019-05033-3