CALCIUM PHOSPHATE VITAMIN-D HOMEOSTASIS AND BONE MASS IN PATIENTS AFTER GASTRECTOMY, VAGOTOMY, AND CHOLECYSTECTOMY

Sixty-two outpatients were assessed and divided into the following gro ups: 20 patients who had had partial gastrectomy (PC group), 22 patien ts who had had truncal vagotomy and pyloroplasty (TV group) or high se lective vagotomy (HSV group), and 20 patients who had had cholecystect omy (CH group). The patients' age ranged from 35 to 64 years (mean 45 years), and the average postoperative period was 9 years. None of the patients evidenced clinical or biochemical symptoms of malnutrition or malabsorption or of diseases affecting vitamin D metabolism. The func tion of the kidneys and the liver was normal. An age-matched group of volunteers served as a control group. The calcium dietary intake was d etermined using a standardized questionnaire; and the levels of serum calcium (Ca-s), phosphate (P-s), alkaline phosphatase (AP), and 25-hyd roxyvitamin D [25(OH)D] and the excretion of Ca in a sample of fasting urine corrected for concurrent creatine excretion (FuCa/cr) were asse ssed by means of standard laboratory techniques. The bone mineral dens ity (BMD) of the lumbar spine (L2-4) and femoral neck (neck-L) was det ermined by means of dual energy x-ray absorptiometry (DXA). The daily Ca dietary intake was lower than recommended (RDA) in 80% of the patie nts, with most of them ingesting less than 300 mg daily. The mean valu es of Ca-s, P-s, AP, and FuCa/cr did not differ from those in the cont rols, Significantly reduced 25(0H)D levels were observed in the PG gro up (7.0 ng/ml) (p < 0.001) and CH group (12.5 ng/ml) (p < 0.01) compar ed with the values in the control group (20.0 ng/ml). The serum 25(OH) D concentration was correlated with the Ca-s level and postoperative p eriod, The BMD of L2-4 was decreased in all postoperative patients com pared to that in the control group (in the PG group the BMD was 80 +/- 2%; in the CH group 95 +/- 2%; and in the TV or HSV group 94 +/- 1%) (p < 0.051. Tn both L2-4 and three sites of the femoral neck it was lo west in the PG group (neck 94 +/- 1%; Ward's triangle 93 +/- 3%; troch anter 95 +/- 2%) compared with the CH group (neck 98 +/- 1%; Ward's tr iangle 100 +/- 1%; trochanter 98 +/- 1%) and with TV or HSV group (94 +/- 1%; 100 +/- 1%; 98 +/- 1%, respectively) (p < 0.05). In the postga strectomy group BMD showed a significant negative correlation with the interval following gastrectomy and Ca excretion in urine but a signif icant positive correlation with the Ca level and serum 25(OH)D concent ration The BMD in the CH group showed a positive correlation only with the serum 25(OH)D concentration. Gastrectomy and cholecystectomy with out postoperative supplementation of Ca and vitamin D led to insidious disturbances in the calcium-vitamin D homeostasis and osteopenia. The refore we suggest that immediate supplementation of calcium and vitami n D be initiated as a routine postoperative procedure, particularly in countries where routine fortification of food with Ca and vitamin D i s not carried out.