The comparison of intra ocular pressure and central corneal thickness measurements between obese, overweġght and healthy volunteers

Obesity has become the epidemic of our time, threatening not only the whole body but also eyes. Obesity is thought to be an independent risk factor for increased intraocular pressure in both men and women in the literature. Patients who admitted to the Adnan Menderes University Ophthalmology Department were included in this prospective controlled study between June 2017 and November 2017. Adnan Menderes University Ethics Committee approved the study. (Reference: 2017/1179). Patients ranging between the ages of 18 and 90 years and who did not have systemic disease such as diabetes and hypertension were included in the study. Patients diagnosed with glaucoma, corneal surface disease and corneal edema were excluded. Three hundered and forty four eyes of 172 patients (115 women, 57 men) underwent full ophtalmic examination including visual acuity, anterior and posterior segment examinations with biomicroscopy, pachymetric evaluation with optical coherance tomography and intraocular pressure with non-contact tonometer. The height and weight measurements of the patients were taken and body mass indexes (BMI) were calculated. Patients were grouped according to group 1 included patients between with 18.5-24.9 kg / m² BMI, group 2 included patients with 25.0-29.9 kg / m², group 3 had patients over 30 kg / m² BMI. Statistical analyzes were performed using Mann-Whitney U, Kruskal Wallis H and Spearman test. The p value <0.05 was considered statistically significant (p <0.05). There was no significant difference in terms of age (p = 0,459), pachymetry (p = 0,0843) and visual acuity (p = 0,627), but there was a significant difference between groups in terms of IOP (p = 0,003). As the body mass index increased, IOP also increased. There was a weak correlation between BMI and IOP (r = 0,191). There was a significant difference between groups with correlation (p = 0.003). Post-hoc analysis showed that the IOP of the obese group of patients in Group 3 was significantly higher than that of Group 1 42 and 2; but no difference was found between groups 1 and 2 in terms of IOP. There was no significant difference between the pachymetre values of the obese group and the other two groups (p> 0.05) (p> 0.05) (p>0.371). (Mean pachymetre values in Group 1: 539,1 ± 35,7; in Group 2: 537,8 ± 30,9; and in Group 3: 539,9 ± 37,4) were as shown. The female patient group had a higher IOP than the male patients (p˂0,001 ). (Mean IOP female: 17,1 ± 4, male: 15,4 ± 3,3); as well they were younger than male (mean age: 53.2 ± 12.2 years; male: 57.4 ± 13.3 years), and their BMI was higher (p˂0.001) (mean BMI female: 30.9 ± 7.5 kg/m²; for men and 27.1 ± 4.3kg/m²). There was no significant difference for pachymetry measurements between man and women. (p = 0.674) (Mean pachymetre value female: 539 ± 35.9, male: 538.9 ± 32.9). Obese patients are in the risk group in terms of ĠOP increase even if they are not diabetic and hypertensive. In our study, each increase of 10 kg/m² BMI rises 1,4 mmHg intraocular pressure. As obesity prevelance increasing all over the World and causing higher intraocular pressure regulation in order to prevent glaucoma and blindness in this group of patients. We believe that our study will make a usefull contribution to the limited and conflicting results of literature about the subject. Future studies with large series of patients measuring intraocular pressure on the same hours of the day are needed. Key Words: Obesity, Intraocular Pressure, Central Corneal Thickness, Body Mass Indeks