Prevalência da deficiência, insuficiência de vitamina D e hiperparatiroidismo secundário em idosos institucionalizados e moradores na comunidade da cidade de São Paulo, Brasil

Abstract

A ocorrência de fraturas osteoporóticas em idosos está relacionada às concentrações reduzidas de vitamina D e conseqüente hiperparatiroidismo secundário, sendo os institucionalizados de maior risco. No Brasil, por seu alto grau de insolação, infere-se que a quantidade de vitamina D da população seja adequada. Neste estudo, objetivamos avaliar as concentrações plasmáticas de 25-hidroxivitamina D (25OHD), paratormônio (PTH) e cálcio ionizado (Cai), assim como analisar a prevalência de hipovitaminose D e de hiperparatiroidismo secundário em idosos moradores da cidade de São Paulo. Estudamos 177 pacientes institucionalizados (125 mulheres e 52 homens) com idade média (DP) de 76,6 (9,0) anos, e 243 idosos ambulatoriais (168 mulheres e 75 homens) com 79,1 (5,9) anos. Nesta avaliação, 71,2% do grupo institucionalizado e 43,8% do ambulatorial possuíam valores de 25OHD menores do que o mínimo recomendado (50 nmol/l), sendo que as mulheres apresentaram valores consideravelmente mais baixos que os homens. O hiperparatiroidismo secundário ocorreu em 61,7% dos pacientes institucionalizados e em 54% dos ambulatoriais. Considerando os resultados obtidos, recomendamos a suplementação com doses eficientes de vitamina D para a população idosa brasileira, alem de sugerir uma discussão para a implementação de políticas de fortificação alimentar com vitamina D, especialmente direcionada àqueles com maior risco. The occurrence of osteoporotic fractures in the elderly is associated with reduced levels of vitamin D and resulting secondary hyperparathyroidism, and inpatients are the ones at a higher risk. In Brazil, given its high level of insolation, the population's large amount of vitamin D is inferred to be adequate. In this study we aimed to assess the serum levels of 25-hydroxivitamin D (25OHD), parathormone (PTH) and ionized calcium (Cai), as well as to analyze the prevalence of both hypovitaminosis D and secondary hyperparathyroidism in the elderly living in the city of São Paulo. We studied 177 inpatients (125 women and 52 men) with mean age (SD) 76.6 (9.0) years, and 243 outpatients (168 women and 75 men) aged 79.1 (5.9) years. In this assessment 71.2% in the inpatients group and 43.8% in the outpatients group had 25OHD levels below the minimum recommended (50 nmol/l), with the women presenting with levels considerably lower than the men. Secondary hyperparathyroidism occurred in 61.7% of the inpatients and in 54% of the outpatients. Considering the results achieved, we recommend vitamin D supplementation in effective doses for the Brazilian elderly population, in addition to suggesting a discussion for the implementation of vitamin D-enhanced food policies, particularly oriented to the ones at a greater risk.

Nutritional aspects of the prevention and treatment of osteoporosis

“…The prevalence of vitamin D inadequacy (defined as < 30 ng/mL) was over 50% in all five world regions, and was highest in the Middle East (81%) and Asia (63%) (17). In Brazil, a cross-sectional study evaluated serum levels of 25-hydroxyvitamin D [25(OH)D] in the elderly living in the city of São Paulo, the authors observed that 71.2% of the inpatient group and 43.8% of the outpatient group had 25OHD levels below the minimum recommended (50 nmol/L) (18). Vitamin D insufficiency was also observed in 24% of women with osteoporosis (19).…”

Risk factors associated with hypovitaminosis D in HIV/aids-infected adults

“…In Brazil, studies carried out in the city of São Paulo show the high prevalence of hypovitaminosis D, both in healthy adolescents (9) and in elderly populations, either institutionalized or not (4). In Recife, a city of tropical humid climate, there was a high prevalence of vitamin D deficiency associated with low bone density in a study carried out with menopausal women (10).…”

“…From the skin, vitamin D 3 gets into the circulation and undergoes a first hydroxylation in the liver, yielding 25(OH)D (calcidiol), the most abundant and stable vitamin D metabolite, which is considered the best indicator of the status of this vitamin in the body (2). After that, circulating calcidiol reaches the kidneys, where it undergoes new hydroxylation and is converted to 1,25(OH) 2 D (calcitriol), an active form of the hormone that acts on several types of cells by means of its nuclear receptor (3), stimulating, for example, the intestinal absorption of calcium and bone mineralization, and regulating the synthesis and secretion of parathormone (PTH) (4).…”

Análise densitométrica da região femoral de homens acima de 50 anos oriundos de um ambulatório de urologia

“…In this assessment, 71.2% of the institutionalized group and 43.8% of the outpatients have shown values of 25 OHD lower than the minimum level recommended (50 nmol/L). 20 In our study of vitamin D in Brazilian men, outpatients aged 50 years or older in Rio de Janeiro (n = 152), we observed high prevalence of hypovitaminosis D (49.4%) and deficiency of vitamin D (31. 9%).…”