Chronic increase of bone turnover markers after biliopancreatic diversion is related to secondary hyperparathyroidism and weight loss. Relation with bone mineral density.
BACKGROUND
Biliopancreatic diversion (BPD) is the most effective bariatric procedure. Around 70% of these patients have secondary hyperparathyroidism (SH) in the long term as a consequence of calcium and vitamin D malabsorption. This work was aimed to study the influence of SH on bone turnover and its relationship with bone mineral density (BMD).


METHODS
Bone turnover markers were determined in 63 BPD patients and 34 morbidly obese controls. In the BPD group, we also studied the influence of age, loss of weight, common channel length, PTH, vitamin D, and serum calcium on bone turnover as well as its relation with BMD.


RESULTS
BPD patients showed significantly higher PTH, osteocalcin, and beta-CTx levels than controls. In the multivariate regression analysis, only PTH (beta=0.42; P=0.0002), menopausal status (beta=0.31; P=0.007) and the percentage of lost BMI (beta=-0.24; P=0.03) significantly predicted the osteocalcin level (R2=0.33; F=9.56; P<0.0001). Similarly, only PTH (beta=0.39; P=0.0005), menopausal status (beta=0.37; P=0.001) and the percentage of lost BMI (beta=-0.23; P=0.04) significantly predicted the beta-CTx level (R2=0.33; F=9.82; P<0.0001). Osteocalcin and beta-CTx levels correlated negatively with BMD at lumbar spine (r=-0.38, P=0.002 and r=-0.30, P=0.02, respectively).


CONCLUSIONS
Chronic SH and the loss of weight determine a high rate of bone turnover that is associated with decreasing BMD in BPD patients.
Balsa
José Antonio
JA
Department of Endocrinology and Clinical Nutrition, Hospital Ramón y Cajal, Carretera de Colmenar Km. 9.1, Madrid, Spaine. jbalsa.hrc@salud.madrid.org
Botella-Carretero
José I
JI
Peromingo
Roberto
R
Caballero
Carmen
C
Muñoz-Malo
Teresa
T
Villafruela
Juan J
JJ
Arrieta
Francisco
F
Zamarrón
Isabel
I
Vázquez
Clotilde
C
D000328:Adult; D000368:Aged; D015904:Biliopancreatic Diversion / Q000009:adverse effects*; D015415:Biomarkers / Q000097:blood; D015519:Bone Density; D001851:Bone Diseases, Metabolic / Q000097:blood* / Q000209:etiology; D001842:Bone and Bones / Q000378:metabolism*; D002908:Chronic Disease; D024042:Collagen Type I / Q000097:blood; D005260:Female; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000097:blood* / Q000209:etiology; D008875:Middle Aged; D009767:Obesity, Morbid / Q000601:surgery*; D015675:Osteocalcin / Q000097:blood; D010281:Parathyroid Hormone / Q000097:blood; D015431:Weight Loss
D015415:Biomarkers; D024042:Collagen Type I; D010281:Parathyroid Hormone; D015675:Osteocalcin