Densidade mineral óssea de idosas independentes com diferentes perfis físico-funcionais e polimorfismos do gene do receptor da vitamina D

Abstract

-The aim of the study was to compare BMD among physically independent elderly women with different physical-functional profiles and vitamin D receptor gene (VDR) polymorphisms, as well as to analyze the effect of the interaction between these last two aspects on BMD. Overall, 165 elderly women had BMD assessed by bone densitometry. Handgrip and lower limb strength and functional exercise capacity (6MWT) were also assessed. VDR polymorphisms (TaqI, BsmI, ApaI and FokI) were analyzed by polymerase chain reaction. For analyses, elderly women were categorized according to their performance on physical-functional tests into low performance (LP; <25th percentile), normal performance (NP; 25th percentile ≤ NP ≤ 75thpercentile) and high performance (HP;> 75th percentile). Regarding functional exercise capacity, LP group showed lower BMD compared to HP and NP groups (p=0,003). With respect to handgrip strength, there was a trend for LP group to have lower bone mineral density compared to NP group (p=0.08). No differences were observed in femur and lumbar BMD in comparisons among the different VDR genotypes (0.07≤p≤0.94); among different groups regarding lower limb strength (p=0.49) and in the interaction analysis among variables (0.17≤p≤0.77). It was concluded that physically independent elderly women with low functional exercise capacity have lower bone mineral density than those classified as normal and high performance. However, apparently, there is no effect of the interaction between VDR gene polymorphisms and physical and functional factors on BMD.Key words: Elderly; Bone density; Exercise tolerance; Genetics. Resumo -O objetivo do estudo foi comparar a DMO entre idosas fisicamente independentes com diferentes perfis físico-funcionais e polimorfismos do gene do receptor da vitamina D (VDR), assim como analisar a interação entre estes dois últimos aspectos sobre a DMO. Participaram do estudo 165 idosas, as quais tiveram a DMO avaliada por meio da densitometria óssea. Foram avaliadas também a força de preensão manual (FPM), força de membros inferiores (FMI) e a capacidade funcional de exercício (TC6min