COMPARATIVE STUDY OF NET CALCIUM ABSORPTION OF TWO DIFFERENT PHARMACEUTICAL FORMULATIONS OF CALCIUM CARBONATE IN POSMENOPAUSAL WOMEN

MASTAGLIA SR; WATSON DZ; SOMOZA J; GAINOTTI R; BRITO G; OLIVERI B

Seattle, Washington

Congreso; Reunión Anual American Society for Bone and Mineral Research; 2015

Calcium supplementation, administered alone or associated to a specific medication for osteoporosis, would reduce bone mass loss and fracture risk in postmenopause. However, the adherence rate to calcium supplements is low, mainly due to low tolerance. New formulations with the same effect but better tolerance are required. Objective: To compare calcium (Ca) net absorption rate, between two different pharmaceutical formulations of calcium carbonate (PFCa) in postmenopausal women. Materials and Methods: Population: 11 postmenopausal women aged 58.9±3yrs with a body mass index (BMI) 25.1±2kg/m2. Inclusion criteria: age: 55-65yrs, Menopause: ≥5yrs. Absence of osteoporosis (defined by T-score ≤-2.5 of Lumbar spine or Total femur or a history of osteoporotic fractures). Exclusion criteria: any medical condition and/or medication affecting mineral metabolism or intestinal Ca absorption. Design: Comparative, randomized, prospective, open-label exploratory crossover study of calcium mousse versus calcium pills. Intervention: Participants were randomized in 2 groups to receive in two periods, 2 different PFCa (500mg): pill vs. mousse, with previous vitamin D3 supplementation and adaptation periods for each. The parathormone (PTH) inhibition test and the area-under-the-curve (AUC) of calcium were studied. Blood samples were taken at baseline (after 12hrs fasting) and 1, 2 and 3 hrs after intake of the assigned PFCa. Urine samples (2hs) were obtained at -baseline, and after 2 and 4 hrs of PFCa intake. Biochemical Determinations: Serum: Calcium (Atomic absorption), phosphorus (Colorimetric); albumin (colorimetric), 25-hydroxyvitamin D (RIA), and iPTH (ECLIA). In urine: calciuria/creatininuria. Statistical Analysis: Performed with SPSS 19.0 software for Windows (Inc, Chicago, IL, USA). The trapezoid rule was applied to assess AUC in time [R Development Core Team (2008).http://www.Rp-project.org]. An ANOVA model with 2 error terms was used to assess the sequence effect, period and formulation. Results: The highest inhibition PTH rates were observed after 2 hrs of PFCa (pill 38.2% vs. mousse 36.7%; p=ns). In Table 1, the analysis of the AUC0-3hrs of both PFCa is shown. Conclusion: In this population sample, the absorption rate with mousse administration was similar to that one. This data would be useful in clinical practice as it would allow a higher adherence to calcium supplementation with a greater therapeutic efficacy.