Dra. Mardones-Leiva, Lorena

Background: Genetic variants within the FTO gene have been associated with increased adiposity and metabolic markers; however, there is limited evidence regarding the association of FTO gene variants with physical activity-related variables. The authors aimed to investigate the association of the rs17817449 single-nucleotide polymorphism of FTO with physical activity, sedentary time, and cardiorespiratory fitness in Chilean adults. Methods: A total of 409 participants from the GENADIO study were included and genotyped for the rs17817449 single-nucleotide polymorphism of FTO in this cross-sectional study. Physical activity and sedentary time were measured with ActiGraph accelerometers. Cardiorespiratory fitness was assessed using the Chester step test. The associations were assessed by using multivariate regression analyses. Results: No associations were found for FTO variant with physical activity levels and cardiorespiratory fitness. The risk allele (G) of the FTO was found to be associated with sedentary time in the minimally adjusted model (β = 19.7 min/d; 95% confidence interval, 4.0 to 35.5, per each copy of the risk allele; P = .006), but the association was no longer significant when body mass index was included as a confounder (P = .211). Conclusion: The rs17817449 single-nucleotide polymorphism of the FTO gene was not associated with the level of physical activity, cardiorespiratory fitness, and sedentary behaviors in Chilean adults.

Antecedentes. El receptor de melanocortina 4 (MC4R) participa en el control del apetito a nivel del sistema nervioso central, a través de la vía de la leptina-melanocortina. Se ha reportado asociación entre diferentes polimorfismos del gen MC4R y la obesidad; sin embargo, existen escasos estudios del polimorfismo de nucleótido simple (SNP) rs483145 de este gen. Objetivo. Investigar su prevalencia y asociación con marcadores de adiposidad en adultos chilenos. Métodos. La prevalencia del SNP rs483145, del gen MC4R, fue determinada en 259 participantes del estudio Genes, Ambiente, Diabetes y Obesidad (GENADIO) mediante reacción en cadena de la polimerasa (PCR) en tiempo real. La asociación del alelo de riesgo de MC4R (A) con marcadores de adiposidad (peso corporal, índice de masa corporal, porcentaje de masa grasa, perímetro de cadera, perímetro de cintura e índice cintura/cadera), se realizó mediante análisis de regresión lineal y fue ajustada por variables de confusión (sociodemográficas y de actividad física) mediante 3 modelos estadísticos. Resultados. Se determinó que la prevalencia del alelo de riesgo (A) del SNP rs483145 del gen MC4R es del 24,5% en la población adulta chilena incluida en este estudio, sin encontrar asociación con ninguno de los marcadores de adiposidad estudiados, tanto en modelos ajustados como sin ajustar.

The purpose of this study was to investigate healthy lifestyle behaviours across age categories in the older population in Chile. Data from 1390 older adults (≥60 years), in the 2009–2010 Chilean National Health Survey were analyzed. We derived the following age categories: 60–65, 66–70, 71–75, 76–80 and >80 years. The associations between age and compliance with healthy lifestyle behaviours (smoking, sitting time, physical activity, sleep duration and intake of salt, alcohol, fruit and vegetables) were investigated using logistic regression. The probability of meeting the guidelines for alcohol intake (OR trend: 1.35 [95% CI: 1.11; 1.64], p = 0.001) and smoking (OR trend: 1.23 [95% CI: 1.13; 1.33], p < 0.0001) increased with age, whereas spending <4 h per day sitting time or engaging in at least 150 min of physical activity per week or sleep on average between 7 and 9 h per day were less likely to be met with increasing age (OR trend: 0.77 [95% CI: 0.71; 0.83], p < 0.000; OR trend: 0.73 [95% CI: 0.67; 0.79], p < 0.0001, and OR trend: 0.89 [95% CI: 0.82; 0.96], p = 0.002, respectively). No significant trend across age categories was observed for fruit and vegetables, and salt intake. The probability of meeting at least 3 out of 7 healthy lifestyle behaviours across the age categories was also lower in older age categories compared to those aged 60 to 65 years. Overall, in older adults the probability of having the healthy lifestyle behaviours of physical activity, sitting time and sleeping behaviours was low but not for smoking or alcohol consumption. With an increasingly ageing population, these findings could inform stakeholders on which lifestyle behaviours could be targeted in the older adults and therefore which interventions should take place to promote healthy ageing.