Comparative 25-OH-vitamin D level in institutionalized women older than 65 years from two cities in Spain and Argentina having a similar solar radiation index

Vitamin D deficiency in older adults and its associated factors: a cross-sectional analysis of the Mexican Health and Aging Study

“…In fact, Portela et al [18–20] reported that the prevalence of vitamin D deficiency is linked with factors such as sex, age, genetics, diet, adiposity, and comorbidities.…”

Lifestyle impact on serum level of vitamin D and PTH, in elderly

“…Attending to these results, we can deduce that in both groups, the average was substantially lower to the values considered sufficient of vitamin D for adults, because values lower than 20 ng/ml translate deficiency of this hormone. In a study realized by M. L. Pita Martin Portela et al 2010, witch aimed to dose the 25(OH)D in institutionalized elderly of two countries with similar solar radiation index, they verified that, even in the end of the summer there were a deficit of vitamin D in both groups. This study seems to indicate that the deficiency of vitamin D is not restrict to a specific season, but transversal to all year, despite the fact that the values of vitamin D tend to be higher during the months of summer (Portela et al, 2010).…”

“…In a study realized by M. L. Pita Martin Portela et al 2010, witch aimed to dose the 25(OH)D in institutionalized elderly of two countries with similar solar radiation index, they verified that, even in the end of the summer there were a deficit of vitamin D in both groups. This study seems to indicate that the deficiency of vitamin D is not restrict to a specific season, but transversal to all year, despite the fact that the values of vitamin D tend to be higher during the months of summer (Portela et al, 2010). The synthesis mechanism of vitamin D tends to suffer alterations with the aging process, not only because of the lower sun exposure, but also due to the compromised capacity to create precursors of vitamin D in the skin, the reduce intake of vitamin D in the diet and, possibly, also because of the decay of the receptors of vitamin D in the duodenum.…”

“…So, the institutionalized group presented lower concentrations of 25(OH)D and higher concentrations of iPTH, while the non-institutionalized revealed higher concentrations of 25(OH)D and lower concentrations of iPTH. Several studies, performed on elderly, support the inverse relation between 25(OH)D and PTH (Portela et al, 2010;Saraiva et al, 2007;Silva et al, 2008). This results reflect the attempt to compensate the insufficiency of vitamin D, through the PTH.…”

“…The hypovitaminosis D is a lack of vitamin increasingly frequent in the developed countries due to dietary errors lower sun exposure and sedentary lifestyle (Silva, Camargos, Fujii, Dias, & Soares, 2008;Thacher & Clarke, 2011). Beyond these aspects, several studies point to hypovitaminosis D even in countries with a lot of sun radiation and in studies made at the final of the summer (Lanhamnew, 2008;Pérez-llamas et al, 2008;Portela et al, 2010). The plasmatic concentration of vitamin D, is interpreted according to reference values assumed for the adults, being that, plasmatic concentrations that are inferior to 20 ng/ml determine state of deficiency of the hormone; values between 20 ng/ml and 30 ng/ml, are considered insufficient; and concentrations between 30 and 100 ng/ml are sufficient when it comes to an adult (Analytics, Ce, & La, 2010).…”