The effects of dimethylformamide exposure on liver and kidney function in the elderly population: A cross-sectional study.

Dimethylformamide (DMF) is widely used as a solvent in the production of synthetic leather. Previous studies have focused on workers exposed to DMF in leather factories; however, little attention has been paid to the general population. This study was conducted to examine the effects of DMF exposure on elderly residents living near synthetic leather factories. A total of 962 subjects over 60 years of age in proximity to these factories (monitoring points) were enrolled as the exposure group, and 1924 permanent residents living distant from the factories were enrolled as the control group. The exposure group was divided into 3 groups according to their distance from the monitoring points. Physical examination, routine blood tests, and liver and renal function data were collected, and the DMF concentration in the air was analyzed by gas chromatography-mass spectroscopy. The prevalence of abnormal heart rhythm, electrocardiogram and B-mode ultrasound results in the exposure group was significantly greater than in the control group. Aspartate transaminase (AST), alanine transaminase (ALT), and blood urea nitrogen (BUN) levels in the exposure group also were higher than those in the control group (P < .01). There was an effect of distance from leather factories on liver and kidney dysfunction in the 3 exposure groups. Compared with the exposure group at >3 km distance from the source, the prevalence of increased AST, ALT, and BUN in the exposure group at <1 km was significantly greater (P < .001). It was concluded that DMF exposure was related to an increased risk of a cardiac injury and liver and kidney dysfunction.

Vitamin D Deficiency in Relation to the Risk of Metabolic Syndrome in Middle-Aged and Elderly Patients with Type 2 Diabetes Mellitus.

Vitamin D deficiency is highly prevalent all over the world and dietary intakes of vitamin D are very low in China. In this study we aimed to determine whether vitamin D deficiency is associated with increased risk of metabolic syndrome (MetS) among Chinese type 2 diabetes mellitus (T2DM) patients aged over 50 y. Serum 25-hydroxyvitamin D [25(OH)D] concentrations were measured in a cross-sectional sample of 270 T2DM patients aged over 50 y from Zhejiang. Data on demographic characteristics, anthropometry and other variables were collected. The mean of serum 25(OH)D was 22.93 ng/mL, and percentages of vitamin D deficiency and insufficiency were 43.71% and 39.63%, respectively. Serum 25(OH)D concentrations were significantly lower in subjects with MetS than in those without MetS (21.74 vs 24.96 ng/mL, p=0.001), and the prevalence of MetS significantly increased according to tertiles of serum 25(OH)D concentrations. After adjusting for multivariate factors, the adverse effect of lower serum 25(OH)D concentrations was significant (OR: 3.26, 95% CI: 1.03-7.34; p=0.044) in the group with BMI≥24 kg/m2 while the change in OR of MetS for each 10 ng/mL decrease in the serum 25(OH)D concentrations was 2.03 (95% CI: 1.10-3.79). These results suggest that serum 25(OH)D deficiency may be a risk factor of MetS among Chinese type 2 diabetic patients, especially in the T2DM with BMI≥24 kg/m2. The challenge is determining the mechanisms of vitamin D action for recommendation of vitamin D supplementation that reduces the risks of MetS and progression to T2DM.

Vitamin D Deficiency Increases the Risk of Gestational Diabetes Mellitus: A Meta-Analysis of Observational Studies.

The results investigating the relationship between vitamin D levels and gestational diabetes mellitus (GDM) are inconsistent. Thus, we focused on evaluating the association of vitamin D deficiency with GDM by conducting a meta-analysis of observed studies. A systematic literature search was conducted via PubMed, MEDLINE, and Cochrane library to identify eligible studies before August 2015. The meta-analysis of 20 studies including 9209 participants showed that women with vitamin D deficiency experienced a significantly increased risk for developing GDM (odds ratio (OR) = 1.53; 95% confidence intervals (CI), 1.33, 1.75) with a little heterogeneity (I² = 16.20%, p = 0.252). A noteworthy decrease of 4.93 nmol/L (95% CI, -6.73, -3.14) in serum 25(OH)D was demonstrated in the participants with GDM, and moderate heterogeneity was observed (I² = 61.40%, p = 0.001). Subgroup analysis with study design showed that there were obvious heterogeneities in nested case-control studies (I² > 52.5%, p < 0.07). Sensitivity analysis showed that exclusion of any single study did not materially alter the overall combined effect. In summary, the evidence from this meta-analysis indicates a consistent association between vitamin D deficiency and an increased risk of GDM. However, well-designed randomized controlled trials are needed to elicit the clear effect of vitamin D supplementation on prevention of GDM.