A Comparison of Accommodative Ability in Healthy Controls, Diabetics, and Healthy Subjects with a Family History of Diabetes.

Background: The aim of this study was to compare accommodative amplitude (AA) and accommodative facility (AF) in healthy subjects with a family history of diabetes (FHD+), individuals with diabetes mellitus (DM), and healthy controls (HC).

Material and methods: This cross-sectional, observational, comparative study was conducted among 89 subjects who attended in the age group between 30 and 40 years. The subjects were categorised into three groups: 30 healthy controls (HC) (mean age: 35.1 ± 4.5 years), 31 healthy subjects with a family history of diabetes (FHD+) (35.5 ± 3.2 years) and 28 subjects diagnosed with diabetes (DM) (36.5 ± 3.5 years). An informed consent form was obtained from subjects before conducting procedures. The amplitude of accommodation was assessed using the minus-lens technique. Additionally, accommodative facility was evaluated monocularly and binocularly using ± 1.50DS flippers. The effects of age, fasting plasma glucose levels, and glycated haemoglobin levels on accommodative parameters were examined using multiple regression analysis. One-way ANOVA with the Bonferroni post hoc test was used to test for significant differences in accommodative parameters.

Results: The mean amplitudes of accommodation for the three groups were statistically significant (Mean AA_DM: 3.4 ± 1.0; Mean AA_FHD+: 4.63 ± 0.83; Mean AA_HC: 6.25 ± 1.33; p = 0.001). Similarly, the mean monocular accommodative facility (AF) for the three groups differed significantly (mean AF_DM:4.35 ± 1.34, mean AF_FHD+: 5.95 ± 1.4; mean AF_HC:7.65 ± 1.18cpm; p = 0.001). In multiple regression, age nearly significantly affected AF in the FHD+ group, with (R² = 0.492, p = 0.040). Whereas, age and FBS were the predictors of AA in FHD+ (R² = 0.598, p = 0.001; R² = 0.400, p = 0.026).

Conclusions: Healthy subjects with a family history of diabetes who are at increased risk of developing prediabetes had reduced accommodations. The AA and AF values are notably lower than the expected value for this age group. Identifying and monitoring these individuals could provide an opportunity for early intervention, potentially delaying the progression of accommodative anomaly-like symptoms associated with DM. This observation highlights the importance of considering family history and prediabetic status when examining accommodative function.