Acute biochemical variations induced by calcium citrate and calcium carbonate in Type 2 diabetic patients: impaired calcium absorption in Type 2 diabetic patients with prolonged gastric emptying time.
Calcium supplementation is important in the treatment of osteoporosis, a disease that may also occur in diabetic patients. The acute effects of calcium supplementation and their relationship to gastric emptying time, however, have rarely been studied in type 2 diabetic patients. We evaluated the acute biochemical variations induced by the administration of two different calcium preparations, calcium citrate and calcium carbonate, in 16 (male/female: 13/3) Chinese diabetic patients. Serum free calcium, intact parathyroid hormone (i-PTH), and amount of urinary excretion of calcium (uCal/uCr) were evaluated after a single dose of 1200 mg of elemental calcium in each preparation. The free calcium levels did not change significantly in either group. However, significant suppression of i-PTH after calcium citrate administration at 1 h (17.1+/-2.0 pg/ml, P=.023), and after calcium carbonate administration at 2 h (14.2+/-2.5 pg/ml, P=.000), was noted when compared with individual basal level (21.2+/-2.5 and 19.3+/-2.4 pg/ml, respectively). The suppressive effect on i-PTH lasted for 6 h after calcium citrate and 5 h after calcium carbonate preparation of the 6-h study period. After administration of calcium citrate, the uCal/uCr of 2-to-4-h collection was significantly higher than that of the basal and 0-to-2-h collections: 0.25+/-0.04 vs. 0.19+/-0.03, P=.025; and 0.25+/-0.04 vs. 0.19+/-0.02, P=.014, respectively. A similar finding was observed for calcium carbonate: 0.23+/-0.03 vs. 0.18+/-0.02, P=.019; and 0.23+/-0.03 vs. 0.18+/-0.02, P=.011, respectively. We conclude that, in this group of Chinese type 2 diabetic patients in our study, the oral administration of 1200 mg elemental calcium in either calcium citrate or calcium carbonate preparation can induce a significant suppression of i-PTH. This may be helpful in preventing or treating osteoporosis. A prolonged gastric emptying time in these diabetic subjects may contribute to the non-significant alteration in free calcium levels after the administration of either calcium preparation.
Division of Endocrinology/Metabolism, Department of Medicine, Taichung Veterans General Hospital, No. 160, Section 3, Taichung-Kang Road, Taichung 407, Taiwan. ymsong@vghtc.vghtc.gov.tw
Y M
YM
Song
W H
WH
Sheu
W J
WJ
Lee
D000284:Administration, Oral; D000368:Aged; D044466:Asian People; D001786:Blood Glucose / Q000378:metabolism; D002118:Calcium / Q000097:blood / Q000378:metabolism*; D002119:Calcium Carbonate / Q000008:administration & dosage / Q000494:pharmacology*; D019355:Calcium Citrate / Q000008:administration & dosage / Q000494:pharmacology*; D003404:Creatinine / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000503:physiopathology*; D005260:Female; D005746:Gastric Emptying; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007408:Intestinal Absorption; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D010710:Phosphates / Q000097:blood; D013624:Taiwan
D001786:Blood Glucose; D002118:Calcium; D002119:Calcium Carbonate; D019355:Calcium Citrate; D003404:Creatinine; D006442:Glycated Hemoglobin; D010281:Parathyroid Hormone; D010710:Phosphates