Association of rate-pressure product with diabetic retinopathy in patients with type 2 diabetes mellitus: development and internal validation of a nomogram for diabetic retinopathy identification.

BACKGROUND

To investigate the association and dose-response relationship between rate-pressure product (RPP) and prevalent diabetic retinopathy (DR), and to develop a nomogram for identifying DR in patients with type 2 diabetes mellitus (T2DM).

METHODS

A total of 1,316 hospitalized patients with T2DM, including 464 with DR, were retrospectively enrolled. LASSO regression was used for variable selection. Correlation analyses, multivariable logistic regression, and restricted cubic spline (RCS) analyses were performed to evaluate the association and dose-response relationship between RPP and prevalent DR. Subgroup analyses were conducted to assess the stability of the association. A nomogram was constructed and evaluated using receiver operating characteristic (ROC) analysis, bootstrap validation, calibration assessment, Brier score, and decision curve analysis.

RESULTS

After full adjustment for confounders, RPP was independently and positively associated with prevalent DR. Per 1-SD increase in RPP was associated with higher odds of DR (OR = 1.292, 95% CI: 1.136-1.469; P < 0.001). RCS analysis showed a significant overall association without evidence of nonlinearity (P for nonlinear > 0.05), and a positive dose-response trend was observed (P for trend < 0.001). The association remained consistent across most subgroups without significant interactions. The nomogram incorporating disease duration, using insulin, HbA1c, and RPP demonstrated acceptable discrimination (AUC = 0.732; bootstrap-corrected AUC = 0.727), good calibration, and favorable clinical utility.

CONCLUSIONS

RPP is independently associated with prevalent DR in patients with T2DM. The RPP-based nomogram shows acceptable discrimination and calibration, suggesting clinical utility for DR identification.