Endocrine Abstracts

Background and aims: Diabetic osteopathy in patients with type 1 diabetes (T1DM) is obvious. However, approaches to its diagnosis are still ambiguous. Thus, the aim was to study the features of serum osteo-specific parameters and dual energy X–ray absorptiometry (DXA) data in T1DM patients.

Materials and methods: 157 patients with T1DM (105 women, 52 males) (mean age: 32.5 (25.5–41.6) yrs, duration of DM: 13 (7–20) yrs, age of manifestation: 19 (14–23) yrs, BMI: 23.43 (21.55–25,70) kg/m²; HbA1c: 8.2 (7.6–8.9) %) and 98 (67 women, 31 men) controls, comparable in sex, age and anthropometric data. The research involved general clinic examination, serum bone-specific parameters, DXA (bone mineral density (BMD) and trabecular bone score (TBS) of lumbar spine). Z–score of –2.0 or less was regarded as «low bone mineral density».

Results: There were no significant differences in L1-L4 BMD and TBS in women compared with men: 1.16 (1.08–1.26 vs. 1.16 (1.08–1.28) g/sm²; (U=5506; P=0.694) and 1.40 (1.35–1.46) vs. 1.44 (1.37–1.49) (U=3230; P=0.097). Similar results were obtained in subgroups of T1DM patients and controls. There was a definite link between BMD (L1–L4) and TBS (L1–L4) – r²=0.33, P<0.001. Low BMD was detected in 14.6% (23) of the surveyed patients with T1DM and 4.1% (4) of controls. T1DM patients compared to controls had lower BMD and TBS: BMD 1.14 (1.04–1.22) vs 1.23 (1.13–1.33) g/cm²; U=3606; P<0.001; TBS 1.39 (1.33–1.46) vs 1.45 (1.39–1.48); U=2775; P<0.001), T-score TBS −0.30 (−1.90–0.30) vs 0.10 (−1.025–0.90); U=248.5; P=0.018; Z-score TBS −0.30 (0.00–0.50) vs. 0.15 (−0.50–1.00), U=617; P=0.092. In T1DM patients was established decreased alkaline phosphatase (77.98 (67.78–85.18) vs 93.4 (75.58–110.8) U/l; U=698; P<0.001) and osteocalcin (10.58 (8.08–15.70) vs 19.73 (15.16–26.30) ng/ml; U=545; P<0.001) compared with the control group. There were an increased osteoprotegerin levels (4.44 (3.38–5.77) vs 2.74 (2.15–3.54) pmol/l; U=94; P<0.001) and a decreased the RANKL/osteoprotegerin ratio (0.03 (0.02–0.06) vs 0.05 (0.04–0.07), U=155; P=0.017).

Conclusions: T1DM patients have decreased bone formation markers (alkaline phosphatase, osteocalcin) and elevated resorption markers (osteoprotegerin), which can lead to impaired mineralization (low BMD) and microstructure (low TBS).