Perda de sensibilidade ao contraste espacial de luminância em sujeitos com história clínica de hipovitaminose B1

Abstract

Vitamin B1 acts directly in the energetic metabolism and its deficiency causes several deficits to the nervous system, including those that occurs in vision that is an important and fundamental sense in the quality of life of the human beings. Studies have been shown that the contrast sensitivity estimative is a good biomarker for evaluation of the visual system and the own nervous system. The present study purposed to compare the contrast sensitivity of subjects with history of hypovitaminosis B1 with healthy subjects living in the cities of Imperatriz and João Lisboa in the Maranhão state from 2006 to 2009. This is a transversal, analytic, and case control study. It was investigated 18 patients with history of hypovitaminosis B1 (13 males, 5 females) with mean age 33.77 ± 9.33 years-old, whose had 35 eyes. The control group was composed by 40 subjects (80 eyes) from both sexes, and mean age 33.25 ± 9.3 years-old. Both groups had similar way of life. For psychophysical evaluation, it was used cathodic ray tubes, 21”, 6 x 5 degrees of visual angle. It was performed a nutritional evaluation of all investigated subjects, further visual acuity and contrast sensitivity evaluation. There were statistical differences between the contrast sensitivity of the control group and the group of the subjects with history of hypovitaminosis B1 at 4, 10, 15 e 20 cpd (two-way ANOVA, α = 0,05, Tukey post-hoc test). Most of the subjects with changes in healthy nutritional condition had changes in the visual evaluation. Clinical complains also had important relationship with visual losses.