麻豆传媒

MONTREAL -- Older adults who experienced a first major osteoporotic fracture had an increased risk for having an additional subsequent fracture, with the risk being higher among men than women.

Men had a three-fold higher risk of sustaining a second fracture within the first year after their index fracture compared with men without a previous fracture (HR 3.3, 95% CI 2.6-4.1), whereas among women with an index fracture, the risk of a second fracture was elevated but to a lesser extent (HR 1.8, 95% CI 1.7-2), according to Suzanne N. Morin, MD of McGill University in Montreal, and colleagues.

"These results underscore the importance of timely recognition of fracture events, especially in men, a population in whom secondary prevention is vastly under-implemented," Morin said in a press release.

"Fragility fractures are associated with subsequent major osteoporotic fractures and excess mortality," she said during a plenary session at the American Society for Bone and Mineral Research annual meeting.

It's been recognized that there is a clustering in time of subsequent osteoporotic and hip fractures soon after an initial fracture, but how this risk evolves over time and whether the evolution is similar in men and women is uncertain. Morin's group undertook a retrospective matched cohort study of men and women included in the Manitoba linked healthcare databases who experienced an initial fracture from 1989 to 2006.

They ensured that there had been no previous fractures in the 5 years prior to the index fracture for each patient, and allowed for at least 10 years and up to 25 years of follow-up to assess for incident fractures.

For each case, they identified three age and sex-matched controls, and all were followed through 2016.

They identified 29,694 index major osteoporotic fractures, with sites being the wrist in 11,028, the hip in 9,313, the humerus in 5,799, and the spine in 3,554. The annual rate of subsequent major osteoporotic fractures was 18.5 (95% CI 17.3-19.8) per 1,000 person years in men and 29.6 (95% CI 28.8-30.4) per 1,000 among women.

The cumulative incidence of subsequent major osteoporotic fractures was higher in cases than in controls in both men and women, and was consistent across all age groups except in the very elderly, where the relationship was reversed because of the competing risk of mortality, she explained.

After the first year, there was a gradual attenuation of risk, but it remained elevated even 15 years after the initial fracture, at which time the hazard ratio for an additional major osteoporotic or hip fracture was 1.8 (95% CI 1.4-2.4) in men and 1.5 (95% CI 1.3-1.6) in women.

This analysis has multiple strengths, according to Morin, including its large, population-based cohort, the long period of follow-up, and the inclusion of a large number of men. Limitations included the reliance on administrative data that did not take into account comorbidities and medication use.