Thijs Engelen, Dieter Smout, Michaël R. Laurent, Hanne Skou Jørgensen, Amaryllis Van Craenenbroeck, Björn Meijers, Kathleen Claes, Bert Bammens, Margo Verbinnen, Evelien Gielen, Pieter Evenepoel
BACKGROUND: Fracture risk in patients with chronic kidney disease (CKD) is excessively high. A recent European consensus provides guidance on the comprehensive screening for CKD-associated osteoporosis in patients with CKD stages G4-5D. However, data on the yield and therapeutic implications of this approach in patients with kidney failure is lacking. METHODS: All prevalent dialysis patients aged > 50 years or postmenopausal with life expectancy > 1 year at a single center were invited for comprehensive bone health assessment, including the evaluation of risk factors, calcium intake, mineral metabolism parameters, bone turnover markers, fracture history, bone mineral density (BMD) and vertebral fractures by dual-energy X-ray absorptiometry (DXA), handgrip strength and self-reported physical activity. RESULTS: Of 203 patients screened, 121 (mean age 75 years, 55% male) were eligible, of whom 71 underwent comprehensive phenotyping including DXA. CKD-associated osteoporosis was identified in 73% of participants, based on a T-score ≤ -2.5 at the hip or lumbar spine (65%), history of fragility fracture (41%) and/or finding of a vertebral fracture (13%). Vitamin D insufficiency (<30 ng/ml) and insufficient calcium intake (<800 mg/day) were observed in 35% and 29%, respectively. Despite bio-intact parathyroid hormone (1-84 PTH) levels exceeding the KDIGO target range in only 17%, bone turnover markers suggested high bone turnover in 53% of patients. Handgrip strength was below sarcopenia threshold in 65%, while physical activity was low in 55% of participants. Only 21% of patients with CKD-associated osteoporosis were treated with bone targeting therapy. CONCLUSION: Comprehensive bone health assessment identified CKD-associated osteoporosis in 7 out of 10 patients with kidney failure and unveiled several therapeutic opportunities ranging from optimization of mineral metabolism to non-pharmacological and pharmacological bone-targeting interventions. Present single-center findings call for reflection and confirmation.