Background: Accumulating evidence demonstrates an association of type 2 diabetes mellitus (T2DM) and its microvascular complications with increased fracture risk. In this study, we aimed to evaluate the relationships between serum concentrations of bone turnover markers and the presence and/or severity of diabetic retinopathy (DR) among patients with T2DM.
Methods: A total of 285 patients with T2DM comprising 168 patients without DR and 117 patients with DR were enrolled in the cross-sectional study. In the latter group, patients were further divided into patients of mild and severe DR stages. The biochemical parameters and bone turnover markers were determined in all participants.
Results: This study found that serum levels of procollagen type 1 N-terminal propeptide (P1NP), a bone formation marker, and the bone resorption marker serum β-cross-linked C-telopeptide of type I collagen (β-CTX) were more decreased in diabetic patients with DR than in those without DR, with differences remaining significant (P < .05) in multivariate linear regression models after adjustments for multiple confounding factors. Osteocalcin and β-CTX levels were further reduced along with the severity of DR among participants with DR. Moreover, multivariate logistic regression analysis revealed that lower serum levels of P1NP and β-CTX were associated with higher odds for the presence of DR, while β-CTX was associated with the severity of DR.
Conclusion: Our results suggest that the development of DR might be involved in the progression of T2DM-induced deficits in bone formation and resorption or vice versa. Follow-up studies and further research are necessary to validate the associations and elucidate the underlying mechanisms.
背景: 越来越多的证据表明2型糖尿病及其微血管并发症与骨折风险增加相关。在这项研究中，我们旨在评估2型糖尿病患者中骨转换标志物的血清水平与糖尿病视网膜病变(diabetic retinopathy,DR)的存在和/或其严重程度的相关性。 方法: 在这项横断面研究中，我们共纳入285例2型糖尿病患者，包括168例无DR的2型糖尿病患者和117例合并DR的2型糖尿病患者。此外，DR组进一步分为轻度病变患者和重度病变患者。所有参与者均测定生化参数和骨转换标志物。 结果: 本研究发现，与无DR相比，DR患者的骨形成标记物1型原胶原N-端前肽(P1NP)和骨吸收标志物1型胶原β交联C端肽(β-CTX)的血清浓度均降低，进一步的多元线性回归模型结果显示，校正多种混杂因素后，该差异仍显著存在(P<0.05)。此外，随着DR的严重程度加重，骨钙素与β-CTX的血清浓度进一步下降。多因素逻辑回归分析显示，低血清水平的P1NP和β-CTX可能与高更的DR发病率相关，而β-CTX与DR的严重程度相关。 结论: 本研究结果提示DR的发生发展可能参与了2型糖尿病引起的骨形成与骨吸收缺陷，或者相反，但尚需进一步研究验证相关性并明确机制。.
Keywords: 2型糖尿病; bone turnover markers; diabetic retinopathy; type 2 diabetes mellitus; 糖尿病视网膜病变; 骨转化标志物.
© 2020 Ruijin Hospital, Shanghai JiaoTong University School of Medicine and John Wiley & Sons Australia, Ltd.