Averting Complications of Proton Pump Inhibitor Therapy by Effervescent Calcium Magnesium Citrate

In a single-dose bioavailability study, the investigators showed previously that provision of calcium and magnesium in a soluble form as EffCaMgCit improved intestinal absorption of calcium and magnesium and suppressed parathyroid function during PPI treatment, compared with calcium carbonate. In a multidosing trial with esomeprazole 40 mg/day for 28 days, EffCaMgCit suppressed parathyroid function and bone turnover, and increased serum and urinary magnesium, compared with placebo. Moreover, EffCaMgCit co-administered with PPI conferred an alkali load, and averted apparent acid load conferred by PPI (when given with placebo). In the current proposal, the investigators wish to conduct a 2-year treatment trial, directed at obtaining more definitive evidence that EffCaMgCit overcomes all three complications of PPI. Aim 1. To test the hypothesis that EffCaMgCit would prevent/treat osteoporosis, by suppressing parathyroid function and bone resorption, thereby stabilizing bone mineral density (BMD). The critical endpoint will be BMD. Secondary endpoints will be serum PTH and C-terminal telopeptide (CTX). Aim 2. To test the hypothesis that EffCaMgCit would prevent/treat hypomagnesemia/magnesium deficiency, by providing bioavailable magnesium. The critical endpoint will be fractional excretion of magnesium (FEMg) and free muscle magnesium by MRS. Secondary endpoints will be serum and urinary magnesium. Aim 3. To test the hypothesis that EffCaMgCit would reduce the risk of CKD during PPI use by averting putative hypomagnesemia/magnesium deficiency and neutralizing acid load. The investigators propose that PPI causes hypomagnesemia/magnesium deficiency and confers an acid load, - factors implicated for incident CKD and its progression. EffCaMgCit is expected to avert incident CKD by providing bioavailable magnesium and alkali load. Critical endpoints will be endogenous creatinine clearance, FEMg, free muscle magnesium and acid-base status.