Vitamin D and calcium prevent bone loss in vitamin D-deficient chronic hepatitis B patients treated with tenofovir disoproxil fumarate: A randomized controlled trial

Tenofovir disoproxil fumarate (TDF) is an important drug to treat chronic hepatitis B (CHB) patients. However, long-term TDF therapy decreases renal function and bone mineral density (BMD). This study compared bone turnover markers, BMD, and renal function in TDF-treated CHB patients with and without vitamin D 2 and calcium supplementation. This 48-week, open-label, randomized controlled trial assigned TDF-treated CHB patients to either a supplement group (n = 32) or a control group (n = 32). At baseline, the mean age was 54.2 years, 57.8% were male, and 17.2% had cirrhosis. Demographic data were comparable in both groups, except body mass index, AST, and ALT were higher in the control group. At 48 weeks, there were no differences in parathyroid hormone, serum creatinine, procollagen-1 N-terminal peptide, and tubular reabsorption of phosphate in both groups. The BMD T score of the total hip did not decrease in the supplement group but significantly decreased in the control group. The C-terminal telopeptide of type 1 collagen increased in only the control group. Subgroup analysis was performed in participants with low baseline vitamin D, the result showed that the median difference in the T score for the total hip in the supplement group also showed a smaller decrease than in the control group. In TDF-treated CHB patients, 48-week vitamin D 2 and calcium supplementation did not meet the primary endpoint of PTH change. However, it was associated with a trend toward preserving BMD, particularly in those with baseline vitamin D deficiency. This study protocol was registered on ClinicalTrials.gov as NCT05313477 on 6/4/2022.