Postmenopausal women who regularly use proton pump inhibitors are at increased risk of suffering hip fractures, a large
US study suggests.
Data on almost 80,000 women showed those who regularly used PPIs over at least two years were 35% more likely to suffer hip fractures than non-users, over an eight-year period.
This risk increased to more than 50% if they were also current or former smokers, found the
study, published Wednesday in the
BMJ.
The risk of hip fracture increased with longer duration of PPI use. However, the effect disappeared within two years of discontinuing PPIs.
The authors suggested PPIs could increase fracture risk by reducing gastric acid secretion, thereby impairing absorption of calcium. Smoking had also been shown to inhibit calcium absorption, they noted.
“Smoking and PPIs may have a synergistic effect on fracture risk mediated by impaired calcium absorption,” wrote the researchers, from Massachusetts General Hospital and Harvard Medical School.
“In addition, experimental studies have postulated that both PPIs and smoking influence osteoclast function, perhaps suggesting a shared negative effect on bone remodelling.
“Our data suggest the importance of carefully evaluating the need for long term, continuous use of PPIs, particularly among individuals with a history of smoking.”
The Therapeutic Goods Administration last year warned about a risk of hypomagnesaemia with prolonged usage.
PPIs were also the subject of a 2009 NPS
campaign (http://www.nps.org.au/news_and_media/media_releases/repository/NPS_urges_judicious_use_of_Proton_Pump_Inhibitors), which urged doctors to limit prescriptions to 4-8 weeks when treating gastro-oesophageal reflux disease, and to step down therapy when appropriate.
The authors of the latest study expressed concern that there could potentially be a huge burden of fractures attributable to PPI use, after figures showed a spike in their use over the eight-year study period.
In 2000 6.7% of women were regularly using PPIs, increasing to nearly 20% in 2008. There were 893 incident hip fractures over the study period, which ran from 2000 to 2008. Participants were drawn from the Nurses' Health Study, who were followed up biennially.
Commenting on the latest study Dr Danielle Stowasser, NPS clinical advisor, told Rheumatology Update’s sister publication Australian Doctor the advice from the 2009 campaign still stood.
“Review the need for ongoing therapy as there are rare, but serious side effects,” she said.
“We recommend using the lowest [possible] dose and frequency of PPIs.”