Association of baseline glycaemic status with BMD change after 12 doses of romosozumab: a retrospective cohort study of 170 patients

Objective We evaluated whether dysglycaemia is an independent factor associated with bone mineral density (BMD) gain during romosozumab treatment. Methods We included all patients who initiated and received 12 doses of romosozumab in two Osteoporosis Centres from January 2019 to March 2025 and had dual-energy X-ray absorptiometry performed at baseline and upon completion of romosozumab. The cohort was divided into three groups. Diabetes was defined by physician diagnosis, glycated haemoglobin (HbA1c) ≥ 6.5%, or anti-diabetic medication use. Among those without known diabetes, HbA1c 5.7%–6.4% defined prediabetes and HbA1c ≤ 5.6% defined normoglycaemia. Percentage of BMD (%BMD) gain while on romosozumab was calculated. Multivariable linear regression analysis was used to identify independent factors associated with %BMD gain. Results A total of 170 patients were included (age 71.6 ± 9.6 years; 167 women, 3 men; body mass index (BMI) 21.0 ± 3.6 kg/m 2 ): 59.4% had normoglycaemia, 25.9% prediabetes, and 14.7% diabetes (all type 2). Of these, 64.1% had prior antiresorptive exposure. Baseline mean BMD T-scores (95% CI) were −3.0 (−3.2, −2.9) (lumbar spine, LS), −2.9 (−3.1, −2.8) (femoral neck, FN), and −2.6 (−2.7, −2.4) (total hip, TH). In total, 69.4% had prior fractures. Overall %BMD gain was 12.1% (95% CI 10.5%–13.7%) (LS), 3.6% (95% CI 2.4%–4.7%) (FN), and 3.4% (95% CI 2.5%–4.3%) (TH). Across the three glycaemic categories, %BMD gain did not differ (LS: p = 0.821; FN: p = 0.776; TH: p = 0.985). HbA1c did not correlate with %BMD gain. Baseline BMD T-score and prior antiresorptive treatment were the independent factors inversely associated with %BMD gain. Conclusion This real-world study showed BMD gains of 12% at the LS and 3.5% at the hip with 12 doses of romosozumab. No statistically significant association was identified between baseline glycaemic category and one-year BMD change during romosozumab treatment. However, the relatively small diabetes subgroup limits the precision of this estimate.