Association between vitamin D serum levels and insulin resistance assessed by HOMA-IR among non-diabetic adults in the United States: Results from NHANES 2007-2014.

Insulin resistance, a pathological response to insulin hormone in insulin-dependent cells, is characterized by the presence of high glucose and insulin concentrations. The homeostasis model of insulin resistance (HOMA-IR) is one of the most used indexes to estimate insulin resistance by assessing the fasting glucose and insulin levels. An association was observed between vitamin D levels and insulin resistance, which varied in different ethnic groups, and there is some evidence that vitamin D supplementation could contribute to the improvement of insulin resistance. This study assessed the association between 25-hydroxyvitamin D (25[OH]D) concentration and HOMA-IR in American adults aged 20 years and older, without diabetes and other chronic diseases that can influence insulin resistance. The data from the National Health and Nutrition Examination Survey (NHANES) 2007-2014 were used by exploiting the free and publicly-accessible web datasets. Linear regression models were performed to evaluate the association between serum 25(OH)D concentration and HOMA-IR, and a negative association was observed, which remained significant following the adjustment for age, gender, race/ethnicity, education, body mass index (BMI), physical activity, the season of examination, current smoking, hypertension, the use of drugs which can influence insulin resistance, serum bicarbonates, triglycerides, and calcium and phosphorus levels. Only in non-Hispanic Blacks was this inverse association between vitamin D and HOMA-IR not observed in the fully adjusted model. Further studies are needed to explain the mechanisms of the observed ethnic/racial differences in the association of vitamin D levels with HOMA-IR.

Core decompression and implantation of calcium phosphate cement/Danshen drug delivery system for treating ischemic necrosis of femoral head at Stages I, II and III of antigen reactive cell opsonization.

OBJECTIVE: To introduce a new method using calcium phosphate cement/Danshen drug delivery system for treating ischemic necrosis of the femoral head and evaluate its curative effect. METHODS: From May 2000 to June 2005, 48 adult patients (54 hips) with ischemic necrosis of the femoral head at Stages I, II and III of antigen reactive cell opsonization (ARCO) were treated with implantation of calcium phosphate cement/Danshen drug delivery system in the involved femoral head. The operation consisted of removal of the necrotic bone under weight-loading cartilage and the implantation of phosphate cement/Danshen drug delivery system, and all manipulations were made percutaneously through a bone tunnel in the trochanter. The functions of the hip joint were evaluated and X-ray films were taken preoperatively and postoperatively. RESULTS: Postoperative follow-up was 45.5 months on average, ranging from 27 to 78 months. According to the evaluation criterion of "Dandong 1995" for therapeutic effect of adult ischemic necrosis of the femoral head, the therapeutic effects were excellent in 33 hips, good in 17, fair in 3 and poor in 1, with the excellent and good rate of 92.6%. CONCLUSIONS: This method is relatively simple with little invasion. It not only improves the microcirculation of the femoral head by local application of traditional Chinese medicine, but also provides mechanic buttress in the weight-loading area to prevent collapse during repairing, which is beneficial to repair and reconstruction of femoral head. It may be a choice of minimal invasion surgery for ischemic necrosis of the femoral head at Stages I, II and III of ARCO.