Heartburn, known medically as gastro esophageal reflux disease (GERD), is commonly treated with medications that decrease the production of stomach acid. Heartburn has nothing to do with the heart, but the pain is felt in the chest – thus the popular name. The pain is caused by the reflux of stomach acid up into the esophagus. This irritates the lower part of the esophagus just above the stomach and causes the painful symptoms of GERD. For more about GERD see Heartburn / GERD on About.com.

An article in the December 27, 2006 issue of the Journal of the American Medical Association found that people who had used GERD medications called proton pump inhibitors (PPIs) for more than one year had an increased risk of hip fracture. The risk was 2.6 times greater among long-term users of higher doses. Overall, those with the highest dosage and longest duration of use had the greatest increase in fracture risk.

These results were based on the comparison of 13,556 people with hip fractures to over 135,000 otherwise similar people who did not experience fractures. The authors of this large study concluded, “For elderly patients who require long-term and particularly high-dose PPI therapy, it may be prudent to reemphasize increased calcium intake, preferably from a dairy source, and coingestion of a meal when taking insoluble calcium supplements.”

Why would these drugs cause this?

Some forms of calcium, like calcium carbonate, dissolve better in an acid solution. Inhibition of stomach acid production with GERD medications may decrease the amount of calcium that is absorbed from a supplement or a meal. The researchers recommended taking a calcium supplement with meals because the meals can stimulate the release of stomach acids and likely help calcium compounds dissolve and be absorbed better.

Calcium citrate supplements are not affected like calcium carbonate by a lack of stomach acid. If you are taking GERD medications and a calcium carbonate supplement, talk to your doctor about switching to a calcium citrate supplement.

Source
Yang, Yu-Xiao, et al. “Long-term Proton Pump Inhibitor Therapy and Risk of Hip Fracture.” Journal of the American Medical Association 296 (2006): 2947-53. (See article abstract)