Table 2

Cox regression model results demonstrating (A) the mean number of antibiotic purchases per follow-up year, and (B) LPS activity, as risk factors for incident severe diabetic retinopathy with prospective, longitudinal ETDRS scores as a time-dependent covariate included in the models to adjust for background retinopathy

CovariateHR (95% CI)P value
Mean number of antibiotic purchases per follow-up year1.05 (0.93–1.18)0.43
Age (years)1.00 (0.98–1.01)0.46
Duration of diabetes (years)0.96(0.94–0.98) <0.001
Sex0.84 (0.65–1.0.8)0.17
Longitudinal ETDRS scores*1.07 (1.06–1.07) <0.001
LPS activity (EU/mL)1.63 (1.02–2.60) 0.04
Freeze time (years)0.97 (0.94–1.00)0.06
Age (years)1.00 (0.98–1.01)0.26
Duration of diabetes (years)0.96 (0.95–0.98) <0.001
Sex0.88 (0.68–1.15)0.36
Longitudinal ETDRS scores*1.06 (1.05–1.07) <0.001
  • *Longitudinal scores used as a time-dependent covariate in the model. Bold values indicates P<0.05.

  • LPS activity, bacterial lipopolysaccharide activity; HR, hazard ratio; ETDRS, Early Treatment Diabetic Retinopathy Study.