Bone Density Is Directly Associated With Glomerular Filtration and Metabolic Acidosis but Do Not Predict Fragility Fractures in Men With Moderate Chronic Kidney Disease.
Hyperparathyroidism, vitamin D deficiency, increased fibroblast growth factor-23 (FGF-23), and metabolic acidosis promote bone fragility in chronic kidney disease (CKD). Although useful in predicting fracture risk in the general population, the role of dual-energy X-ray absorptiometry (DXA) in CKD remains uncertain. This cross-sectional study included 51 men aged 50-75 yr with moderate CKD. The stage 4 CKD patients had higher levels of parathyroid hormone (p<0.001), FGF-23 (p=0.029), and lowest 25-hydroxyvitamin D (p=0.016), bicarbonate (p<0.001), total femur (p=0.003), and femoral neck (p=0.011) T-scores compared with stage 3 CKD patients. Total femur and femoral neck T-scores were directly correlated with serum bicarbonate (p=0.003, r=0.447 and p=0.005, r=0.427, respectively) and estimated glomerular filtration rate (p=0.024, r=0.325 and p=0.003, r=0.313, respectively) but were not significantly associated with parathyroid hormone, 25-hydroxyvitamin D, or FGF-23. Only 3.9% of the participants had osteoporosis on DXA scan, whereas 31.4% reported a low-impact fracture. Our data point to a pivotal role of metabolic acidosis for bone impairment and to the inadequacy of DXA to evaluate bone fragility in CKD patients.
Division of Endocrinology, Universidade Federal do Rio de Janeiro, Hospital Universitário Clementino Fraga Filho, Rio de Janeiro, Brazil. Electronic address: gaclima@yahoo.com.br.
Guilherme Alcantara Cunha
GA
Lima
Division of Endocrinology, Universidade Federal do Rio de Janeiro, Hospital Universitário Clementino Fraga Filho, Rio de Janeiro, Brazil.
Francisco
F
de Paula Paranhos-Neto
Division of Endocrinology, Universidade Federal do Rio de Janeiro, Hospital Universitário Clementino Fraga Filho, Rio de Janeiro, Brazil.
Luciana Colonese
LC
Silva
Division of Rheumatology, Universidade Federal do Rio de Janeiro, Hospital Universitário Clementino Fraga Filho, Rio de Janeiro, Brazil.
Laura Maria Carvalho
LM
de Mendonça
Division of Nephrology, Universidade Federal do Rio de Janeiro, Hospital Universitário Clementino Fraga Filho, Rio de Janeiro, Brazil.
Alvimar Gonçalves
AG
Delgado
Division of Nephrology, Universidade Federal do Rio de Janeiro, Hospital Universitário Clementino Fraga Filho, Rio de Janeiro, Brazil.
Maurilo
M
Leite
Division of Nephrology, Universidade Federal do Rio de Janeiro, Hospital Universitário Clementino Fraga Filho, Rio de Janeiro, Brazil.
Carlos Perez
CP
Gomes
Division of Endocrinology, Universidade Federal do Rio de Janeiro, Hospital Universitário Clementino Fraga Filho, Rio de Janeiro, Brazil.
Maria Lucia Fleiuss
ML
Farias
D015502:Absorptiometry, Photon / Q000379:methods; D000138:Acidosis / Q000209:etiology / Q000378:metabolism; D000368:Aged; D015519:Bone Density; D001938:Brazil; D003430:Cross-Sectional Studies; D005269:Femur / Q000000981:diagnostic imaging / Q000378:metabolism; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000097:blood; D005919:Glomerular Filtration Rate; D006801:Humans; D006961:Hyperparathyroidism / Q000209:etiology / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D058866:Osteoporotic Fractures / Q000209:etiology / Q000378:metabolism; D011237:Predictive Value of Tests; D051436:Renal Insufficiency, Chronic / Q000150:complications / Q000378:metabolism / Q000503:physiopathology; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013223:Statistics as Topic; D014808:Vitamin D Deficiency / Q000209:etiology / Q000378:metabolism
C000717427:FGF23 protein, human; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23
Chronic kidney disease; FGF-23; dual-energy X-ray absorptiometry; fractures; metabolic acidosis