Assessment of bone mineral density in tenofovir-treated patients with chronic hepatitis B: can the fracture risk assessment tool identify those at greatest risk?

BACKGROUND Tenofovir disoproxil fumarate (TDF) is an established nucleotide analogue in the treatment of chronic hepatitis B. Bone mineral density loss has been described in TDF-treated patients with human immunodeficiency virus infection, but limited data exist for patients with chronic hepatitis B. Dual X-ray absorptiometry (DEXA) was used to determine bone mineral density changes in TDF-exposed patients. We evaluated the accuracy of the Fracture Risk Assessment Tool (FRAX) as an alternative to DEXA in clinical practice. METHODS A total of 170 patients were studied: 122 were exposed to TDF, and 48 were controls. All patients underwent DEXA, and demographic details were recorded. FRAX scores (before and after DEXA) were calculated. RESULTS TDF was associated with a lower hip T score (P = .02). On univariate and multivariate analysis, advancing age, smoking, lower body mass index, and TDF exposure were independent predictors of low bone mineral density. In addition, the pre-DEXA FRAX score was an accurate predictor of the post-DEXA FRAX treatment recommendation (100% sensitivity and 83% specificity), area under the curve 0.93 (95% CI, .87-.97, P < .001). CONCLUSIONS TDF-treated patients with chronic hepatitis B have reduced bone mineral density, but the reduction is limited to 1 anatomical site. Age and advanced liver disease are additional contributing factors, underlining the importance of multifactorial fracture risk assessment. FRAX can accurately identify those at greatest risk of osteoporotic fracture.