Correlation of Body Mass Index with Visual Acuity among Adults

Abstract

At present, increased BMI and visual impairment are becoming serious public health concerns worldwide, according to WHO, in 2022 more than 1 billion people are overweight/obese, and 2.2 billion people are facing far or near visual impairment problems and which is rapidly increasing in most countries. And according to world obesity federation (WOF),5.4 million school-aged Pakistani students will be obese in 2030. Objective: To assess that body mass index has an association with visual acuity among adults in the population. Methodology: BMI is being calculated and visual acuity data is noted in the following way. Height was measured using a measuring tape by asking the subject to stand (without any footwear) erect and placing the heel and back against the wall and the readings were taken to the nearest 0.1 cm. Weight was measured using a digital weighing machine, with the subject standing bare feet in such a way as to exert equal weight on both feet. Body Mass Index was evaluated by dividing the weight in kilograms by the square of the height in meters (weight (kg)/Height (m2)). Visual acuity (VA) of each eye was measured one by one using a Snellen chart. The Snellen’s chart was hung on a wall at a distance of six (6) meters from the subject and a height of two (2) meters in a well-lit room. Visual acuity was measured in one eye at a time (poor-vision eye first) with the subject standing opposite the chart and reading out loud the letters on the charts starting from the top line towards down. The other eye (not being examined yet) was covered with an eye occluder by the researcher. The level of the lineup to which the respondents were able to see at that specific distance was recorded. And with that other data about their age, nutritional statuses, work routine, screen, or sleep time were noted on proformas. Then chi-square for qualitative data, spearman correlation, and ANOVA is being used to assess the association having considered p value < 0.05 Results: The bivariate evaluation shows no significant correlation is found between BMI and visual acuity. ANOVA shows a significant relationship between height and visual acuity with a p-value <0.05. Fisher exact test evaluates a significant association between gender and left eye visual acuity with p < 0.05. Conclusion: No association between BMI and visual acuity is found but an association between height and visual acuity is found along with a relation between gender and left visual acuity is formed.