Discordancia en autopercepción de peso en población adulta de Talca

Resumen

Background: Obesity is related to underestimation of one’s own
weight. Aim: To determine the agreement between nutritional status and self perception of weight
status in apparently healthy adults from Talca. Subjects and methods: Data were obtained from
a survey applied at 1007 randomly selected subjects, aged 18-74 years old (66% women). The
survey identified age, gender, educational level and socioeconomic status. Self-perception of
weight was estimated with pictures representing the four nutritional status categories:
underweight, normal, overweight and obese. Body Mass Index (BMI, kg/m2) was calculated to
determine nutritional status. Statistical analysis included kappa index, Bowman’s symmetry test
and a logistic regression model to calculate the odds ratio in different variables related to
underestimation of weight. Results: Seventy three percent of subjects were overweight or obese
and 44% underestimated their nutritional status. Sixty percent of subjects with a BMI between 25
and 26 kg/m2, perceived themselves as normal. A higher underestimation was observed in obese
subjects (odds ratio (OR) 17.2 95% confidence intervals (CI) 10.9-27.1), in overweight individuals
(OR 3.5 95% CI 2.3-5.3), in men (OR 1.5 95% CI 1.1-2.1) and in people aged from 45 to 59 years
(OR 1.7 95% CI 1.0-2.7). Conclusion: Almost half of studied population had an erroneous selfperception
of weight, mainly due to underestimation. Obese subjects, males and people older than
45 years were those with the higher degree of underestimation