Intraocular Pressure and Associated Factors. The Central India Eye and Medical Study

Jost Jonas

Purpose: To determine intraocular pressure (IOP) range in a rural Central Indian population and to evaluate ocular, medical, and socioeconomic factors associated with IOP.

Methods: This is a population-based study performed in Nagpur in Central India. Single IOP measurement was taken using Goldmann applanation tonometry. Over 200 independent variables were entered into logistic regression analysis and variables with significant P-values (P<0.05) were entered into a multivariable logistic regression analysis. .

Results: Of 5885 eligible subjects, 9338 eyes of 4686 subjects were included in the study. Mean IOP was 13.6±3.4 mmHg (median:14 mmHg; range: 2-56 mmHg). In multivariate regression analysis, the following factors, with coefficients of determination and P-values reported in parentesis, were found to be associated with IOP. Ocular factors included higher corneal power (0.12;P=0.004), lower central corneal thickness (0.02;P<0.001), and higher myopic refractive power (-0.13;P=0.001). Medical factors included diastolic blood pressure (0.05;P<0.001), pulse rate (0.02;P=0.005), and body mass index (0.05;P=0.01). Socioeconomic factors included level of education (0.15;P=0.05) and livestock ownership (-0.18;P=0.008).

Conclusion: Low mean IOP was found when compared to other epidemiologic studies and this may be explained by the low central corneal thickness found in the study population. Several known ocular and medical factors as well as new socioeconomic factors were found to be associated IOP. Identifying risk factors associated with IOP in different populations may allow clinicians to better define and recognize subgroups of patients at risk for elevated IOP. Newly identified socioeconomic-IOP associations will need to be validated in future studies.