Eficácia da reposição de vitamina D3 em idosos na dose de 50.000 ui por semana durante 8 semanas: é o suficiente?

Abstract

INTRODUCTION: Vitamin D deficiency is frequently noticed in the elderly. However, there are still doubts about the supplementation levels required to achieve the normalization of such deficiency. OBJECTIVE: To evaluate the efficacy of vitamin D replacement with weekly oral doses of 50,000 IU in community elders of the Federal District, Brazil. METHODS: Clinical, interventional, quasi-experimental study with 89 community volunteers, aged 60 and older, living in the Federal District, 15ºS. Variables on habits, medication use, dosage (chemiluminescence) of serum 25 (OH) D, parathyroid hormone (PTH), calcium, and phosphorus were analyzed. Supplementation with vitamin D3 was performed in 24 volunteers with sufficient 25-OH VITD (≥ 30 ng/mL) at a dose of 800 IU per day; in 20 subjects with deficiency of 25-OH VITD (< 20 ng/mL), and in 45 subjects with insufficiency of 25-OH VITD (20 to 29 ng/mL) a dose of 50,000 IU per week for 8 weeks was used. RESULTS: Hypovitaminosis D was identified in 70.9% being deficient in 24.3% and insufficient in 46.6% of the subjects. Supplementation for 8 weeks resulted in an average gain of 8.27 ng/mL. In the group with D hypovitaminosis, there was a persistent insufficiency in 49.2% of volunteers, adequacy in 46.1% and deficiency only in 4.6%. In the group with deficiency the average gain were 12.90 ng/mL (92.5% gain), being 7.80 ng/mL (33.0% gain) in the deficiency group and 5.25 ng/mL (16.0% gain) for the group with no vitamin D deficiency. There was no evidence connecting the gains to gender and age group. Patients treated with antipsychotics and bisphosphonates had lower gains compared to the average. CONCLUSIONS: Despite the statistically significant gain — mean 8.2 ng/mL — in volunteers who received a dose of 50,000 IU of vitamin D3 weekly, results show that after the treatment of vitamin D deficiency, 58.3% of pacients with hyposufficiency did not reach normal concentrations in the period of 8 weeks. Volunteers taking antipsychotics and bisphosphonates had significant smaller gains in vitamin D concentrations with the supplementation.