Influence of Height, Weight, and Body Mass Index on Optic Disc Parameters
ABSTRACT To examine the influence of body height, body weight, and body mass index (BMI) on optic disc parameters in a population-based study.
The Singapore Malay Eye Study examined 3280 persons of Malay ethnicity, aged 40 to 80 years, of whom 2329 (71.0%) had reliable retinal scanning confocal laser tomography images for analyses. Intraocular pressure (IOP) was ascertained by Goldmann applanation tonometry. Body height and weight were measured with standardized protocols; BMI was calculated as weight (kilograms)/height squared (meters). Sociodemographic information was collected in an interviewer-administered questionnaire.
In univariate analyses, body height, weight, and BMI were significantly associated with optic cup area, rim area, and cup-to-disc area ratio (all with P < 0.05) but none of the anthropometric parameters was significantly associated with optic disc area (all with P > 0.05). In multiple regression analyses after adjustment for age, sex, optic disc size, axial length, education, family income, and IOP, each SD increase in body height was associated with a 0.042-mm(2) decrease in optic rim area and a 0.020 increase in optic cup-to-disc area ratio; each SD decrease in body weight was associated with a 0.013-mm(2) decrease in optic rim area and a 0.010 increase in optic cup-to-disc ratio; and each SD decrease in BMI was associated with a 0.021-mm(2) decrease in optic rim area and a 0.010 increase in optic cup-to-disc ratio.
Persons who are taller or have lower BMI have a smaller neuroretinal rim area and a larger optic cup-to-disc area ratio.
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