Infection with Soil-Transmitted Helminths Is Associated with Increased Insulin Sensitivity

• Published in: PloS one Vol. 10; no. 6; p. e0127746
• Main Authors: Wiria, Aprilianto E, Hamid, Firdaus, Wammes, Linda J, Prasetyani, Margaretta A, Dekkers, Olaf M, May, Linda, Kaisar, Maria M M, Verweij, Jaco J, Guigas, Bruno, Partono, Felix, Sartono, Erliyani, Supali, Taniawati, Yazdanbakhsh, Maria, Smit, Johannes W A
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 10-06-2015; Public Library of Science (PLoS)
• Subjects: Adult; Adults; Ancylostoma; Animals; Ascaris lumbricoides; Blood glucose; Body mass; Body mass index; Body size; C-reactive protein; Cross-Sectional Studies; Diabetes; Disease transmission; Endocrinology; Energy balance; Epidemiology; Ethnicity; Female; Helminthiasis - epidemiology; Helminthiasis - immunology; Hip; Humans; Hypotheses; Immune system; Immunoglobulin E; Indonesia; Infection; Infections; Inflammation; Insulin; Insulin Resistance; Internal medicine; Laboratories; Male; Medicine; Metabolic syndrome; Microbiota; Microscopy; Middle Aged; Necator americanus; Obesity; Parasitic diseases; Parasitology; Prevalence; Prevalence studies (Epidemiology); Regression analysis; Regression models; Sensitivity; Soil - parasitology; Soil investigations; Strongyloides stercoralis; Studies; Trends; Trichuris; Tumor necrosis factor-TNF; Jakarta Indonesia; Netherlands; Indonesia
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0127746

Given that helminth infections have been shown to improve insulin sensitivity in animal studies, which may be explained by beneficial effects on energy balance or by a shift in the immune system to an anti-inflammatory profile, we investigated whether soil-transmitted helminth (STH)-infected subjects are more insulin sensitive than STH-uninfected subjects.
We performed a cross-sectional study on Flores island, Indonesia, an area with high prevalence of STH infections.
From 646 adults, stool samples were screened for Trichuris trichiura by microscopy and for Ascaris lumbricoides, Necator americanus, Ancylostoma duodenale, and Strongyloides stercoralis by qPCR. No other helminth was found. We collected data on body mass index (BMI, kg/m2), waist-to-hip ratio (WHR), fasting blood glucose (FBG, mmol/L), insulin (pmol/L), high sensitive C-reactive protein (ng/ml) and Immunoglobulin E (IU/ml). The homeostatic model assessment for insulin resistance (HOMAIR) was calculated and regression models were used to assess the association between STH infection status and insulin resistance.
424 (66%) participants had at least one STH infection. STH infected participants had lower BMI (23.2 vs 22.5 kg/m2, p value = 0.03) and lower HOMAIR (0.97 vs 0.81, p value = 0.05). In an age-, sex- and BMI-adjusted model a significant association was seen between the number of infections and HOMAIR: for every additional infection with STH species, the HOMAIR decreased by 0.10 (p for linear trend 0.01). This effect was mainly accounted for by a decrease in insulin of 4.9 pmol/L for every infection (p for trend = 0.07).
STH infections are associated with a modest improvement of insulin sensitivity, which is not accounted for by STH effects on BMI alone.