Vitamin D deficiency has been associated with impaired glucose metabolism, but its predictive value for diabetes status remains incompletely characterized. We applied machine learning methodologies to investigate this relationship and develop predictive models based on vitamin D levels and clinical parameters. This cross-sectional study analyzed data from 817 patients with concurrent measurements of 25-hydroxyvitamin D and HbA1c. Patients were classified as having normal glucose metabolism (HbA1c<5.7%), prediabetes (HbA1c 5.7-6.4%), or diabetes (HbA1c≥6.5%). Logistic regression models of increasing complexity were developed to predict diabetes status, and various vitamin D thresholds were evaluated to determine the optimal cutoff for diabetes prediction. Mean vitamin D levels differed significantly across glycemic categories (normal: 24.57 ng/mL, prediabetes: 25.41 ng/mL, diabetes: 21.85 ng/mL; ANOVA: F(2,814)=4.68, P<0.01). Model-specific performance analysis revealed limited discriminative ability across all models: basic vitamin D model (AUC: 0.55, 95% CI: 0.51-0.59), demographic model incorporating age and gender (AUC: 0.58, 95% CI: 0.54-0.62), and comprehensive model with additional biomarkers (AUC: 0.62, 95% CI: 0.56-0.68). In the logistic regression model, each 1 ng/mL increase in vitamin D was associated with a 4% decrease in diabetes odds (OR: 0.96, 95% CI: 0.93-0.99). The statistically optimal vitamin D threshold for diabetes prediction was 14.0 ng/mL (sensitivity: 31.9%, specificity: 89.3%), differing from the conventional clinical cutoff of 20 ng/mL. However, the weak discriminative ability indicates that vitamin D has limited standalone predictive value for diabetes status and should be considered only as part of comprehensive risk assessment frameworks. The cross-sectional design precludes causal inferences, and the modest performance suggests limited immediate clinical applicability as an isolated predictor.
Vitamin D deficiency Diabetes mellitus HbA1c Machine learning Predictive modeling
Ethical approval for this study was obtained from the Gebze Technical University Rectorate, Ethics Committee for Human Research (Approval Date: March 28, 2024; Approval Number: 2024-05/07) and from the T.C. Istanbul Medipol University Health Education, Application and Research Center – Pendik Unit Ethics Committee (Approval Date: April 15, 2024; Approval Number: 48430706-259). The study utilized anonymized clinical data with no patient identifiers. All procedures were conducted in accordance with the ethical standards of the institutional research committees and with the 1964 Helsinki Declaration and its later amendments. As this was a retrospective analysis of anonymized data, the requirement for individual patient consent was waived by the institutional review boards.
Vitamin D deficiency has been associated with impaired glucose metabolism, but its predictive value for diabetes status remains incompletely characterized. We applied machine learning methodologies to investigate this relationship and develop predictive models based on vitamin D levels and clinical parameters. This cross-sectional study analyzed data from 817 patients with concurrent measurements of 25-hydroxyvitamin D and HbA1c. Patients were classified as having normal glucose metabolism (HbA1c<5.7%), prediabetes (HbA1c 5.7-6.4%), or diabetes (HbA1c≥6.5%). Logistic regression models of increasing complexity were developed to predict diabetes status, and various vitamin D thresholds were evaluated to determine the optimal cutoff for diabetes prediction. Mean vitamin D levels differed significantly across glycemic categories (normal: 24.57 ng/mL, prediabetes: 25.41 ng/mL, diabetes: 21.85 ng/mL; ANOVA: F(2,814)=4.68, P<0.01). Model-specific performance analysis revealed limited discriminative ability across all models: basic vitamin D model (AUC: 0.55, 95% CI: 0.51-0.59), demographic model incorporating age and gender (AUC: 0.58, 95% CI: 0.54-0.62), and comprehensive model with additional biomarkers (AUC: 0.62, 95% CI: 0.56-0.68). In the logistic regression model, each 1 ng/mL increase in vitamin D was associated with a 4% decrease in diabetes odds (OR: 0.96, 95% CI: 0.93-0.99). The statistically optimal vitamin D threshold for diabetes prediction was 14.0 ng/mL (sensitivity: 31.9%, specificity: 89.3%), differing from the conventional clinical cutoff of 20 ng/mL. However, the weak discriminative ability indicates that vitamin D has limited standalone predictive value for diabetes status and should be considered only as part of comprehensive risk assessment frameworks. The cross-sectional design precludes causal inferences, and the modest performance suggests limited immediate clinical applicability as an isolated predictor.
Vitamin D deficiency Diabetes mellitus HbA1c Machine learning Predictive modeling
Ethical approval for this study was obtained from the Gebze Technical University Rectorate, Ethics Committee for Human Research (Approval Date: March 28, 2024; Approval Number: 2024-05/07) and from the T.C. Istanbul Medipol University Health Education, Application and Research Center – Pendik Unit Ethics Committee (Approval Date: April 15, 2024; Approval Number: 48430706-259). The study utilized anonymized clinical data with no patient identifiers. All procedures were conducted in accordance with the ethical standards of the institutional research committees and with the 1964 Helsinki Declaration and its later amendments. As this was a retrospective analysis of anonymized data, the requirement for individual patient consent was waived by the institutional review boards.
| Birincil Dil | İngilizce |
|---|---|
| Konular | Bilgi Sistemleri (Diğer), Biyomedikal Bilimler ve Teknolojiler |
| Bölüm | Research Articles |
| Yazarlar | |
| Erken Görünüm Tarihi | 12 Kasım 2025 |
| Yayımlanma Tarihi | 15 Kasım 2025 |
| Gönderilme Tarihi | 3 Mart 2025 |
| Kabul Tarihi | 1 Kasım 2025 |
| Yayımlandığı Sayı | Yıl 2025 Cilt: 8 Sayı: 6 |