Excessive generalized and visceral adiposity is associated with a higher prevalence of diabetic retinopathy in Caucasian patients with type 2 diabetes.

BACKGROUND AND AIMS: Type 2 Diabetes Mellitus (T2D) has heterogeneous clinical phenotypes related to different risk of developing diabetes complications. We investigated the correlation between generalized and abdominal adiposity and the prevalence of both micro- and macrovascular complications in Caucasian patients with T2D. METHODS AND RESULTS: We evaluated 769 individuals with T2D consecutively referred to our diabetes center. Body mass index (BMI), waist circumference (WC), waist to hip (W/H) ratio, glycated hemoglobin (HbA1c), systolic and diastolic blood pressure, lipid profile, smoking habit, diabetes therapy, and micro- and macrovascular complications were recorded. Patients were divided into three groups based on BMI and WC: non-obese with normal WC (nWC, n = 220), non-obese with excess of abdominal fat (AF, n = 260) and obese (Ob, n = 289). We found that nWC, compared with AF and Ob individuals, were predominantly males (p<0.01), had lower HbA1c (p<0.01), diastolic blood pressure (p<0.01), triglycerides (p<0.01), and showed a significantly lower prevalence of diabetic retinopathy (DR) (p = 0.01). The rate of proliferative DR was significantly higher in Ob (13.2 %) compared to the other groups (p = 0.03). Multivariate analyses showed a significantly decreased prevalence of DR in nWC compared to both AF (OR 0.58, 95 CI 0.34-0.96; p = 0.03) and Ob (OR 0.57, 95 CI 0.33-0.98; p = 0.04) individuals. Conversely, DR was associated, mainly in women, to higher WC and W/H ratio. The prevalence of the other diabetes-related complications was similar among the studied groups. CONCLUSIONS: In our population, nWC subjects showed a lower prevalence of DR. An increased generalized and abdominal adiposity was associated to a higher prevalence of DR, especially among females.

Effect of gluten-free diet on autoimmune thyroiditis progression in patients with no symptoms or histology of celiac disease: a meta-analysis.

Background: Hashimoto's thyroiditis (HT) is the most common autoimmune disease. HT may be associated with nonthyroidal autoimmune diseases, including celiac disease (CD) or other gluten-related conditions (GRC). In the last years, interest about gluten-free diet (GFD) has increased for its supposed extraintestinal anti-inflammatory effect; thus, many patients with HT initiate GFD on their own. Objectives: The aim of this meta-analysis is to examine all available data in literature about the effect of a GFD on TgAb, TPOAb, TSH, FT4, and FT3 levels in patients with HT and no symptoms or histology of CD. Methods: The study was conducted according to MOOSE (Meta-analysis Of Observational Studies in Epidemiology). The search was performed on databases PubMed and Scopus. The last search was performed on 7 February 2023. Quality assessment was performed. Meta-analyses were performed using the random-effect model. Hedges' g was used to measure the effect size (ES). Statistical analyses were performed using StataSE 17. Results: The online search retrieved 409 articles, and 4 studies with a total of 87 patients were finally included for quantitative analysis. The risk of bias was generally low. The mean period of GFD was almost 6 months. The meta-analyses showed reduction in antibody levels with ES: -0.39 for TgAb (95% CI: -0.81 to +0.02; p = 0.06; I² = 46.98%) and -0.40 for TPOAb (95% CI: -0.82 to +0.03; p = 0.07; I² = 47.58%). TSH showed a reduction with ES: -0.35 (95% CI: -0.64 to -0.05; p = 0.02; I² = 0%) and FT4 showed an increase with ES: +0.35% (95% CI: 0.06 to 0.64; p = 0.02; I² = 0%). FT3 did not display variations (ES: 0.05; 95% CI: -0.38 to +0.48; p = 0.82; I² = 51%). The heterogeneity of TgAb, TPOAb, and FT3 data was solved performing sub-analyses between patients with or without GRC (TgAb p = 0.02; TPOAb p = 0.02; FT3 p = 0.04) and only for FT3, performing a sub-analysis between patients taking and not taking LT4 (p = 0.03). Conclusion: This is the first meta-analysis investigating the effect of GFD on HT. Our results seem to indicate a positive effect of the gluten deprivation on thyroid function and its inflammation, particularly in patients with HT and GRC. However, current lines of evidence are not yet sufficient to recommend this dietary approach to all patients with a diagnosis of HT.