Who are the older Australians referred for a bone density scan? Data from the Barwon region

We investigated the reasons for referral of older Australians aged 70 years and older to dual energy X-ray absorptiometry (DXA). The most common clinical indication was being aged 70 years and older, followed by monitoring for fracture or low bone mineral density (BMD). Compared to males, females were twice as likely to have osteoporotic BMD.

Little is known about reasons for the referral of older Australians to dual energy X-ray absorptiometry (DXA) for bone mineral density (BMD) measurements. Thus, we aimed to document the reasons for referral to DXA in Australian men and women aged 70 years and older and investigate any differences between the sexes.

Reasons for DXA referral were examined in 5438 patients aged ≥ 70 years (78.5 % female), referred to the Geelong Bone Densitometry Service, south-eastern Victoria, 2003-2010. Clinical indication codes derived from patient records were used to ascertain reasons for referral. We ascertained age, sex and BMD measures at the femoral neck and spine for each patient.

The most common reason for DXA referral was being aged ≥ 70 years (64.6 %), followed by monitoring of fracture or low BMD. In this referred population, a greater proportion of men than women had BMD in the normal range (men 30.2 % vs. women 10.9 %, p < 0.001), whereas sex differences in the opposite direction were seen for BMD in the osteopenic range (women 47.7 % vs. men 44.3 %, p = 0.04) and in the osteoporotic range (women 41.4 % vs. men 25.5 %, p < 0.001). After age adjustment, women were twice as likely to have BMD in the osteoporotic range compared to men (odds ratio (OR) 2.25, 95% confidence interval (95%CI) 1.95-2.61).

For both sexes, the most common reason for referral was being aged 70 years or older. Referred women were twice as likely as men to have BMD in the osteoporosis range. These data suggest that even more women may need to be referred to DXA.