[Measurement of pupillary diameter in diabetic and non-diabetic patients: a case-control study]. / Mesure du diamètre pupillaire chez les patients diabétiques et non diabétiques : étude cas-témoins.

ABSTRACT

PURPOSE: To study the effect of type 2 diabetes on pupil diameter. PATIENTS AND METHODS: We carried out a case-control study at the Douala Obstetrics, Gynecology and Pediatric Hospital over a 5-month period. The cases were type 2 diabetic patients, and the controls were non-diabetic patients paired for age and gender. We studied the correlation between the duration of diabetes, fasting blood sugar and the horizontal pupil diameter. RESULTS: We included 35 patients in each group. The mean age was 56.6±10.01 years. Both groups included 17 males and 18 females. The mean duration of diabetes was 2.72±4.31 years, and the mean fasting blood sugar was 2.02±0.69g/L. The mean pupil diameter was similar in the two groups. On the right side, it was 4.75±0.73mm for controls and 4.52±0.69mm for cases (P=0.179). On the left side, it was 4.70±0.68mm and 4.42±0.73mm respectively for each group (P=0.101). The duration of diabetes was correlated to pupil diameter in the right eye (r=-0.43; P=0.01) and left eye (r=-0.45; P<0.01). No additional risk was found to be associated with diabetes for right pupil diameters (OR=0.79; P=0.33), or for left ones (OR=0.76; P=0.24). CONCLUSION: Pupil diameter is similar in diabetic and non-diabetic patients. However, the duration of diabetes appears to affect pupil diameter.