Insuficiência e deficiência de vitamina D em pacientes portadores de doen？a renal cr？nica

introduction: vitamin d deficiency is common among patients with chronic kidney disease (ckd). a higher level of serum vitamin d is expected in residents of the tropics in relation to inhabitants of non-tropical regions, due to greater sun exposure and increased production of vitamin d. objective: to analyze serum levels of vitamin d, such as 25-hydroxyvitamin d - 25(oh)d, in brazilian patients at the predialytic stage with ckd. methods: we studied 125 patients (aged 57.4 ± 16.2 years, 78 were white and 55.2%, male), with creatinine 2.67 ± 1.73 mg/dl and creatinine clearance 43.7 ± 34.5 ml/min. body mass index was 27.4 ± 4.7 kg/m2, and waist circumference was 95.0 ± 14.0 cm. calcium was 9.3 ± 0.6 mg/dl, intact parathormone (ipth) 212.6 ± 221.2 pg/ml and serum albumin 4.2 ± 0.6 g/dl. the mean 25(oh)d was 23.9 ± 10.7 ng/ml. results: out of the 125 patients, we found that 92 (72.6%) had suboptimal levels of 25(oh)d < 30 ng/ml, and 65 (52%) had vitamin d insufficiency (15-29 ng/ml); 27 (21.5%) had deficiency (5-14 ng/ml) and only one patient had severe vitamin d deficiency <5 ng/ml. no differences were observed among the levels of 25 (h)d in stratified patients as to the ckd stage. levels of 25(oh)d were higher among males (38.1 ± 20.6 versus 22.4 ± 9.7 ng/ml; p < 0.0001), and there was an inverse correlation between levels 25(oh)d and ipth, proteinuria and abdominal circumference, and a positive correlation between 25(oh)d and calcium and serum albumin. multivariate analysis only showed inverse correlation between serum 25(oh)d and ipth and abdominal circumference. conclusion: even though the brazilian population live in a tropical region, most patients had suboptimal levels of serum vitamin d, and this pattern may play a role in the development of hyperparathyroidism.