Objective  To explore the predictive value of the blood uric acid/creatinine ratio (SUA/Cr) and the Osteoporosis Self-Assessment Tool for Asians (OSTA) for osteoporosis (OP) in middle-aged, older, and elderly adult Tibetan populations in Xizang.

Methods  A total of 1058 middle-aged and older adult ethnic Tibetans who underwent physical examination in Xizang between June 2020 and December 2023 were selected for the study. Fasting venous blood samples were collected for laboratory analysis. The bone mineral density (BMD) of the radius of the participants was measured using dual-energy X-ray absorptiometry. Based on the BMD measurement results and OP diagnostic criteria, participants were divided into the OP group (n = 759) and the non-OP group (n = 299). Multivariate logistic stepwise regression analysis was used to further identify independent predictors associated with OP risk in the middle-aged and older adult Tibetan population. The predictive value of SUA/Cr and OSTA for OP was evaluated using the receiver operating characteristic (ROC) curve.

Results  1) The OP prevalence among the middle-aged and older adult Tibetan populations was 28.3% (299 people), including 209 females (69.9%) and 90 males (30.1%). Significant differences between the two groups were found in terms of age (OP group: 62 54, 69 vs non-OP group: 56 51, 62), SUA/Cr (OP group: 6.86 5.06, 10.23 vs non-OP group: 5.36 4.36, 6.52), and OSTA (OP group: －1.27 ± 3.06 vs non-OP group: 1.25 ± 2.68) (P < 0.05). 2) SUA/Cr (OR: 1.592, 95% CI: 1.469-1.726) was identified as a risk factor for OP, while OSTA (OR: 0.706, 95% CI: 0.662-0.752) was a protective factor for OP (P < 0.05). 3) For gender-based group analysis, the combined use of SUA/Cr and OSTA showed better diagnostic performance for OP, with AUCs of 0.807 (95% CI: 0.751-0.863) for males and 0.820 (95% CI: 0.782-0.857) for females. For age-based group analysis, the combined diagnosis of OP using SUA/Cr and OSTA provided the best performance, with the optimal cutoff value increasing with age. 4) In the middle-aged group and the older adult male group, the combined use of SUA/Cr and OSTA for OP diagnosis was more effective than using SUA/Cr or OSTA alone (P < 0.001). In the elderly adult male group, the AUC for SUA/Cr was 0.954 (95% CI: 0.858-1.000), with a sensitivity of 88.9% and specificity of 100.0%, indicating excellent predictive performance. In females, the diagnostic effectiveness of OSTA and the combined use of SUA/Cr and OSTA increased with age across different age groups.

Conclusion  The predictive performance of SUA/Cr and OSTA for OP varies across different sex and age groups in the Tibetan population. Both SUA/Cr and OSTA can be used to predict OP in middle-aged and older adult Tibetan populations, with the combined use of SUA/Cr and OSTA providing better predictive performance.