The risk of osteoporosis is twice as high in people with inflammatory bowel disease (IBD) as in the general population, a Danish study found.
The study, “Incidence, risk factors and evaluation of osteoporosis in patients with inflammatory bowel disease – a Danish population-based inception cohort with 10 years of follow-up,” was published in the Journal of Crohn’s and Colitis.
Osteoporosis — a condition that weakens bones, making them more porous, fragile, and prone to fractures —is a common complication among IBD patients. The condition is marked by a progressive reduction in bone mineral density (BMD), or bone density loss, which develops silently and progressively and is often only diagnosed when a fall or sudden impact causes a bone fracture.
The use of corticosteroids, chronic inflammation, vitamin D deficiency caused by food malabsorption, and low body mass index (BMI) are some of the factors thought to contribute to osteoporosis in IBD patients.
Corticosteroids tend to lessen the body’s ability to absorb calcium and to speed bone destruction. The more and the longer a person takes these medications, the greater the risk of developing osteoporosis.
Yet few studies have addressed the prevalence of osteoporosis among those with IBD, or investigated possible screening practices.
There are no specific recommendations for how frequently IBD patients should be screened for bone loss (by dual-energy X-ray absorption, also known as DXA or DEXA scans), and current European guidelines do not address precautions for specific risk factors in these patients.
Researchers at Copenhagen University Hospital Hvidovre in Denmark conducted a population-based study with a decade of follow-up to investigate the frequency of osteoporosis and its screening practices, as well as specific risk factors increasing the propensity for the condition among those with IBD.
A total of 513 patients — 213 with Crohn’s disease and 300 with ulcerative colitis — diagnosed in 2003 and 2004 in an area of Copenhagen were followed until 2015. Their data were compared to a control population.
Overall, 338 IBD patients (66%) — 164 (77%) with Crohn’s disease and 174 (58%) with ulcerative colitis — had taken a total dose of steroid medications equal to or greater than 500 mg of prednisolone within a year.
Such exposure to steroids was estimated to result in 781 patient years at risk of osteoporosis. However, only 83 (10.6%) patient years were actually followed for bone loss with DXA scans within the same or the following two years, an “infrequent” and “limited” monitoring, the researchers said.
A patient year is a statistical measure used by researchers to address trends, or the risk of a specific condition or event. In this case, it indicates how many patients are estimated to be at risk of osteoporosis per year.
During follow-up, a total of 73 patients (14.2%) were diagnosed with osteoporosis — 31 (14.6%) with Crohn’s disease and 42 (14%) with ulcerative colitis — which was higher than the 680 (6.6%) observed in the general population.
“The risk of osteoporosis was increased compared to the control population,” wrote the researchers, who found that IBD patients had two times the risk of developing osteoporosis.
Nevertheless, the frequency of low-energy fractures (fall from a standing height or a height of less than one meter) was similar between the IBD group and the control population (3% in both groups).
Risk factors for osteoporosis and osteopenia (bone loss that precedes osteoporosis) were also analyzed.
Those 50 or older at the time of IBD diagnosis were found to have a higher risk of osteoporosis, in both Crohn’s disease and ulcerative colitis patients. Hospitalizations were also associated with a greater risk of osteoporosis in people with Crohn’s disease.
Men with ulcerative colitis appeared to have a lower risk of developing osteoporosis compared with women, regardless of age.
“In this population-based inception cohort, the incidence of osteoporosis was significantly higher compared to a control population,” the researchers said. “Measurement of bone mineral density is infrequent, especially in patients at high-risk of developing osteoporosis.”
Doctors and patients should be more aware of the risks of developing osteoporosis and its associated complications, they noted, adding that larger, population-based studies are needed to characterize in more detail those risks and help define screening practices.