NEW YORK (Reuters Health) – People with HIV treated at outpatient clinics may be at an increased risk of bone fractures, according to a new study published in Clinical Infectious Diseases.

Over the years from 2000 to 2006, patients in the HIV Outpatient Study (HOPS) consistently had higher rates of fracture than a comparison group from the general population, and also had a higher relative proportion of fragility fractures.

The findings show that these patients should be regularly screened for low bone mineral density starting at younger age than other groups have recommended, the authors say.

Led by Dr. Benjamin Young of Rocky Mountain CARES/DIDC in Denver, the authors identified 5,826 eligible patients in HOPS, a prospective cohort study of adults visiting 10 different HIV clinics in 8 U.S. cities. Using diagnoses recorded at clinic visits, the authors compared fracture rate in these individuals to data from the CDC and the National Hospital Ambulatory Medical Care Survey of outpatient departments.

Patients included in HOPS were a mean age of 40, 79 percent were male, and 73% had been exposed to ART. The racial breakdown of the population was 52% white, 33% black, and 12% Hispanic.

Rates of bone fracture increased in HOPS patients over time, from 57.7 fractures per year per 10,000 people in 2000 to 89.9 in 2008. Fracture rates in the comparison NHAMCS-OPD group, however, did not significantly increase over time.

Standardized fracture rates in HOPS patients were consistently higher than rates from NHAMCS-OPD. In 2006, the last year of available data for NHAMCS-OPD, overall fracture rates were 83.2 (95% CI: 65.2-146.3) per 10,000 among HOPS patients compared to 35.9 (95% CI: 24.1-53.5) per 10,000 in the NHAMCS-OPD database.

Compared to population-wide data, HOPS patients age 25 to 54 had a higher proportion of fragility fractures, including fractures of the wrist (significant for men only), femoral neck of the hip (significant for women only), and vertebra (significant for both men and women.)

Among those with HIV, multivariate analysis showed that patients who had diabetes (HR = 1.62), hepatitis C infection (HR = 1.61), and low Nadir CD4+ counts (HR = 1.60 for <200 cells/mm3) were at higher risk of a bone fracture, as were substance abusers (HR = 1.52) and older patients (HR = 1.58 for ? 47 vs. ? 35).

The findings are consistent with previous research that has shown that people with HIV have high rates of low bone density, and also with recommendations for bone density screening in this population, including those from the European AIDS Clinical Society.

However, those recommendations call for screening starting at age 40, while Young and his colleagues argue that these findings suggest a need for early initiation of bone density screening.

While how to best manage the bone health of patients with HIV has been controversial in the past, they note, the authors conclude that,