SYDNEY, Australia—One of the few prospective cohort studies to examine absolute as well as relative low-trauma refracture risks in older community-dwelling men and women shows that men are as likely as women to suffer a second fracture. The researchers also report that use of antiresorptive therapy and/or calcium/vitamin D supplementation is even rarer in men than in women.¹

"Our findings show a similar absolute risk for sustaining a subsequent fracture in men and women. This similar absolute risk reflected a 2-fold greater increase in refracture risk for men than for women. Importantly, this was across all age groups and for virtually all fractures, with the increased absolute risk persisting for up to 10 years after the initial fracture event," lead author Jacqueline R. Center, MBBS, PhD, writes in the January 24 Journal of the American Medical Association.1

16-year follow-up data on 4000 subjects

Dr. Center and colleagues at the Bone and Mineral Research Program of the Garvan Institute of Medical Research, in Sydney, Australia, are conducting the Dubbo Osteoporosis Epidemiology Study, a prospective cohort study launched in 1989 to examine osteoporosis and related issues in community dwelling men and women aged 60 or older living in the city of Dubbo, Australia. The investigators have access to all radiological services provided in the Dubbo area, which has one hospital and a population of 32,000.

They identified 905 women and 337 men who were at least 60 years old, and who had sustained an initial low-trauma fracture over a median of 16 years between 1989 and April 2005. Of those patients, 65% of the women (n = 584) and 63% of the men (n = 211) agreed to detailed, ongoing assessments that included smoking, alcohol, and dietary calcium intake, number of falls in the last year, comorbid conditions and medications, anthropometric measurements, bone mineral density (BMD) of the lumbar spine and femoral neck, quadriceps strength, and body sway. The investigators calculated time to subsequent fracture and risk of subsequent fracture in intervals of 0–2, 0–5, 5–10, and >e;10 years after initial fracture.

As expected, initial fracture risk was higher in women than in men and increased with age. However, absolute refracture risks were similar for women and men [Table]. Since the initial population risk was lower in men, this meant that the relative risk (RR) of refracture was >50% higher for men than for women.

"For women, the absolute refracture risk was equivalent to or greater than the initial fracture risk of a woman 10 years older," the authors write. "For men, the absolute risk of a subsequent fracture was similar to that of women and equivalent to or greater than an initial fracture risk of a woman 10 years older...and similar to the initial risk of a man at least 20 years older." Interestingly, during the first 5 years after the initial fracture, the absolute refracture risk was greater for older than for younger women but similar for men for all ages.

Even after fracture, few received osteoporosis treatment

Even after an initial low-trauma fracture, rates of osteoporosis preventive therapy were dismal. Calcium and/or vitamin D supplementation were being used by 23% of the women and 3% of the men (P <.001), and antiresorptive therapy rates were 14% for women and 4% for men (P <.001).

The risk of refracture was highest in the first few years after the initial low-trauma fracture. "[V]irtually all low-trauma fractures indicate the clinical need for fracture preventive therapy, and given the early peak of refracture, such preventive treatment should not be delayed. The lack of consideration of osteoporosis and treatment initiatives by the medical profession and the public, particularly in relation to men, should be the focus of education initiatives," the researchers concluded.

The study was funded by the Australian National Health & Medical Research Council, Merck Sharp & Dohme, Eli Lilly and Co, and GE Lunar Corporation.

Table 1: Risk of Refracture After First Low-Trauma Fracture

Subjects