FRAX Prediction With and Without Bone Mineral Density Testing

Of the 119 patients included in the study, 98 patients (82.4%) had the same treatment recommendation when the FRAX score was calculated with and without BMD. The remaining 21 patients (17.6%) had different treatment recommendations when FRAX scores were calculated with BMD compared with FRAX scores calculated without BMD. Treatment was recommended based on risk prediction for 43 of the 98 patients who had identical treatment recommendations. Of the 21 patients who had different treatment recommendations, treatment was recommended based on risk prediction for 14 patients when FRAX scores were calculated with BMD. Treatment was recommended for the other 7 patients when FRAX scores were calculated without BMD.

Of the numeric variables evaluated, mean age, femoral neck BMD, and T-score were all significantly different between the 2 groups (Table 2). Patients with an identical treatment recommendation were a mean age of 67.9 years (SD: 10.2 y), and patients with different treatment recommendations were a mean age of 62.2 years (SD: 8.9 y) (P = .011). Patients with an identical treatment recommendation had a mean BMD of 0.9 (SD: 0.2), and patients with different treatment recommendations had a mean BMD of 0.8 (SD: 0.1) (P = .021). Patients with an identical treatment recommendation had a mean T-score of -1.7 (SD: 1.2), and patients with different treatment recommendations had a mean T-score of -2.3 (SD: 1.1) (P = .031). Mean weight, height, and vitamin D level were not statistically significantly different between the 2 groups.

Of the binary variables evaluated, only glucocorticoid use was significantly different between the 2 groups. Of the patients with an identical treatment recommendation, 4 (4.1%) received a glucocorticoid.

Discussion

The purpose of this retrospective study was to determine whether using FRAX without BMD was as effective as using FRAX with BMD in predicting the risk of osteoporotic fractures and in providing identical treatment recommendations in male veteran patients. The results of this study revealed that FRAX calculations without BMD provided identical treatment recommendations as FRAX calculations with BMD for 82.4% of male veteran patients. These findings were similar to the findings of another study by Gadam and colleagues, in which 84% of patients had identical treatment recommendations when calculating FRAX scores with and without BMD.⁶ In contrast, a prospective cohort study by Ettinger and colleagues found that the addition of BMD to the FRAX calculation enhanced the performance of the FRAX tool by correctly identifying more patients who experienced a fracture within the following 10 years.⁸

Several of the risk factors evaluated in the present study were indicative of an identical treatment recommendation. Age was one of the risk factors that differed significantly between the 2 groups. The mean age of patients with an identical treatment recommendation was 67.9 years, and the mean age of patients with different treatment recommendations was 62.2 years (P = .011). These findings opposed the findings in the Gadam and colleagues’ study.⁶ The results of that study revealed that younger age rather than older age was more indicative of an identical treatment recommendation. The study by Gadam and colleagues included both male and female patients; however, the majority of patients included in the Gadam study were female (96%).⁶ Because the present study included only male patients, a comparison of the results was difficult because of the different patient populations.

A higher T-score (P = .031) and a higher BMD (P = .021) were the other 2 risk factors associated with an identical treatment recommendation with and without BMD. The Gadam and colleagues study did not find these to be significant risk factors for identifying an identical treatment recommendation.⁶

The FRAX calculation without BMD identified all the patients meeting treatment criteria based on the FRAX calculation with BMD except for 14 of the 119 patients (11.8%). Therefore, > 88% of patients who met treatment criteria based on FRAX calculated with BMD also met treatment criteria based on FRAX without BMD.

The FRAX calculation has several advantages, including risk stratification in men and identifying those with other conditions that may predispose them to a fracture.⁷ Therefore, before obtaining a DXA scan, it would be reasonable to calculate a FRAX score without BMD to identify patients who are at high risk for fracture but who may not receive treatment because they are not considered to need a DXA scan or a DXA scan is not feasible.