Andréa Matos

The relationship between serum vitamin A and breast cancer staging before and after radiotherapy

INTRODUCTION Several adverse effects of radiotherapy have been associated with the process of increased oxidative stress in the organism. In this context, vitamin A noteworthy for its important role in combating oxidative stress, in addition to its chemoprotective effect. OBJECTIVE To assess the serum levels of vitamin A (retinol and β-carotene) and their relationship to breast cancer staging in patients before and after radiotherapy. METHODS This is a prospective study of women with breast cancer who were evaluated from October 2011 to September 2012 before (T0) and after radiotherapy (T1-7 days). Serum retinol and β-carotene levels were analyzed using High Performance Liquid Chromatography. The assignment of breast cancer stages was based on the classification of malignant tumors that has been proposed by the International Union Against Cancer. RESULTS 230 patients (mean age 63.6 years, SD ± 9.38) were evaluated. There was a significant reduction in the serum retinol (45.1 ± 18.2 μg/dL at T0 to 27.1 ± 11.7 μg/dL at T1, p < 0.001) and β-carotene (209.0 ± 153.6 μg/L at T0 to 47.7 ± 25.5 μg/L at T1, p < 0.001). There was also a significant difference in serum retinol (p < 0.001) and β-carotene (p = 0.003) levels based on the disease stage. CONCLUSIONS It is recommended the early establishment of adequation serum concentrations of retinol and beta-carotene, offering nutritional assistance for those patients with deficiencies, in order to minimize the harmful effects of radiation.

Effect of vitamin A supplementation on clinical evolution in patients undergoing coronary artery bypass grafting, according to serum levels of zinc

Vitamin A and zinc are powerful antioxidants with synergy between them, thus protecting the organism against oxidative stress during the pre and postoperative periods. Our aim was to investigate the evolution clinical in patients undergoing coronary artery bypass grafting while receiving vitamin A supplements according to their zinc nutritional status. They were randomly divided into two groups (2:1): Control group (G1 = 60); and Supplemented group (G2 = 30) and subdivided according to the nutritional status of zinc. Serum concentrations of retinol, β-carotene, zinc and levels of malondialdehyde were measured prior to (T0) and on the 21st day (T1) following surgery. After surgery, was found a significant difference between G1 and G2 when comparing retinol (G1 = 38.7 ± 17.1 μg/dL and G2 = 62.1 ± 20.3 μg/dL; p < 0.001) and β-carotene (G1 = 12.3 ± 5.7 μg/dL and G2 = 53.5 ± 20.9 μg/dL; p < 0.001) in the patients with adequate concentrations of zinc. Analyzing the evolution clinical, operative mortality was 8.33% in G1 and 3.33% in G2. Hospitalization time significantly smaller in the G2 was found in the patients who had adequate concentrations of zinc (p = 0.001), as well as time in the intensive care unit both in those with adequate and inadequate levels of zinc (p = 0.047; p = 0.039). Such results may indicate that vitamin A supplementation may have a positive impact in combating the oxidative stress to which these patients are exposed above all in patients with adequate levels of zinc.

Maternal Anthropometry and Its Relationship with the Nutritional Status of Vitamin D, Calcium, and Parathyroid Hormone in Pregnant Women After Roux-en-Y Gastric Bypass

ObjectiveTo assess the influence of pre-pregnancy body mass index (BMI), total gestational weight gain (TGWG), and pre-pregnancy surgical success on the nutritional status of vitamin D, calcium, and parathyroid hormone (PTH) in the trimesters of pregnancy of women who previously underwent Roux-en-Y gastric bypass (RYGB).MethodologyThis is an analytical, longitudinal, and retrospective study comprising 42 pregnant women who previously underwent RYGB. Concentrations of vitamin D3, calcium, and PTH were assessed in all trimesters. Anthropometric variables necessary for calculating TGWG, surgical success, and BMI were collected preoperatively and over the trimesters of pregnancy.ResultsA total of 97.1% had vitamin D3 inadequacy at some point in pregnancy. Pre-pregnancy BMI, even when classified as overweight, may have exacerbated the serum concentrations of this vitamin in the third trimester (p = 0.011), and it was significantly lower in women with normal weight and/or obesity (p = 0.039). It was evidenced that both pre-pregnancy BMI and TGWG above the recommended optimal weight can be associated with calcium homeostasis, especially early in pregnancy. It was also shown that surgical success in the pre-pregnancy period may have influenced the serum concentrations of vitamin D in the second trimester of pregnancy (p = 0.013).ConclusionThis study draws attention to the importance of monitoring the nutritional status of vitamin D3 and calcium in the prenatal period due to its relationship with pre-pregnancy BMI, TGWG, and surgical success.

Relationship between the Nutritional Status of Vitamin A per Trimester of Pregnancy with Maternal Anthropometry and Anemia after Roux-en-Y Gastric Bypass

The aim of this study was to compare the nutritional status of vitamin A per trimester of pregnancy, as well as to assess its influence on pre-pregnancy BMI, total gestational weight gain (TGWG) and presence of anemia in women who had previously undergone Roux-en-Y gastric bypass (RYGB). An analytical, longitudinal and retrospective study comprising 30 pregnant women who had previously undergone RYGB was undertaken. In all trimesters of pregnancy, the serum concentrations of retinol, β-carotene, stages of vitamin A deficiency (VAD), night blindness (NB), anemia and anthropometric variables were assessed. VAD in pregnancy affected 90% of women, 86.7% developed NB and 82.8% had mild VAD. TGWG above/below the recommended range was related to the low serum concentrations of β-carotene (p = 0.045) in the second trimester and women with TGWG above the recommended range showed 100% of inadequacy of this nutrient in the third trimester. Among the pregnant women with anemia, 90.9% had VAD and 86.4% had NB. This study highlights the importance of monitoring the nutritional status of vitamin A in prenatal care, due to its relationship with TGWG and the high percentage of VAD and NB found since the beginning of pregnancy. It also reaffirms the use of the cut-off <1.05 μmol/L for determining VAD.