Israel Medical Association Journal

Background: Trabecular bone score (TBS) reflects vertebrae microarchitecture and assists in fracture risk assessment. The International Society of Clinical Densitometry postulates that the role of TBS in monitoring antiresorptive therapy is unclear. Whether changes in TBS correlate with bone resorption measured by bone turnover markers is not known.

Objectives: To determine whether longitudinal changes in TBS correlate with C-terminal telopeptide (CTX) of type I collagen.

Methods: Examinees with two bone mineral density (BMD) measurements were detected via the institutional database. Over 5.8% change in TBS was considered least significant and patients were grouped accordingly (increment, decrement, or unchanged). CTX, BMD, co-morbidities, incident fractures, and medication exposure were compared between the groups by Kruskal-Wallis. The correlation between TBS and BMD change and CTX in a continuous model was analyzed by Pearson's correlation coefficient.

Results: In total, 110 patients had detailed medical records. In 74.5%, TBS change was below least significant change. Two other TBS categories, fracture incidence or medication exposure, did not differ by CTX. In the continuous model, BMD and TBS change was positively correlated (r = 0.225, P = 0.018). A negative correlation was observed between BMD change and CTX. The decrease in BMD level was associated with higher CTX (r = -0.335, P = 0.004). No correlation was observed between CTX and TBS.

Conclusions: No correlation between TBS dynamics and bone resorption marker was found. Clinical interpretation and implication of longitudinal TBS changes should be further explored.

Background: Chronic fatigue is common among patients with rheumatoid arthritis (RA), affecting quality of life. Osteoporosis is a prevalent co-morbidity in RA patients.

Objectives: To assess the effect of long-term treatment with tocilizumab on fatigue and bone mineral density (BMD) in RA patients with inadequate response to synthetic or biologic disease-modifying anti-rheumatic drugs. 

Methods: In this multicenter, open-label, non-controlled, single-arm study, patients ≥ 18 years of age received intravenous tocilizumab 8 mg/kg every 4 weeks for 96 weeks. The primary outcome was the change in Functional Assessment of Chronic Illness Therapy (FACIT)-Fatigue score from baseline to weeks 24, 48, 72, and 96. BMD was assessed before and 96 weeks after treatment. 

Results: The study comprised 145 patients (mean age 53.4 ± 13.4 years, 83.4% women). Of these, 88 (60.7%) completed the 2 year treatment period. The mean FACIT-Fatigue score improved consistently starting from week 4 and showed a statistically significant increase of 5.0 ± 9.7, 6.8 ± 10.5, 7.3 ± 10.9, and 7.3 ± 10.4 from baseline to weeks 24, 48, 72, and 96, respectively (P < 0.0001). Mean BMD of femoral neck and total spine remained stable. Disease activity, acute phase reactants, and composite efficacy measures decreased during the study, while hemoglobin levels increased. Adverse events and serious adverse events were as expected for the known and previously described data.

Conclusions: Tocilizumab therapy for 2 years significantly and clinically decreased fatigue. BMD remained stable and no new safety issue was reported.