Association Between Long-term Exposure to Air Pollution and Biomarkers Related to Insulin Resistance, Subclinical Inflammation, and Adipokines

Abstract

Insulin resistance (IR) is present long before the onset of type 2 diabetes and results not only from inherited and lifestyle factors but also likely from environmental conditions. We investigated the association between modeled long-term exposure to air pollution at residence and biomarkers related to IR, subclinical inflammation, and adipokines. Data were based on 2,944 participants of the KORA (Cooperative Health Research in the Region Augsburg) F4 study conducted in southern Germany (2006-2008). We analyzed associations between individual air pollution concentration estimated by land use regression and HOMA-IR, glucose, insulin, HbA, leptin, and high-sensitivity C-reactive protein levels from fasting samples using multivariable linear regression models. Effect estimates were calculated for the whole study population and subgroups of individuals who did not have diabetes, had prediabetes, or had diabetes. Among all participants, a 7.9 μg/m increment in particulate matter of <10 μm was associated with higher HOMA-IR (15.6% [95% CI 4.0; 28.6]) and insulin (14.5% [3.6; 26.5]). Nitrogen dioxide was associated with HOMA-IR, glucose, insulin, and leptin. Effect estimates for individuals with prediabetes were much larger and highly statistically significant, whereas individuals who did not have diabetes or had diabetes showed rather weak associations. No association was seen for HbA level. Our results suggested an association between long-term exposure to air pollution and IR in the general population that was attributable mainly to individuals with prediabetes.

Particulate Matter Air Pollution and the Risk of Incident CKD and Progression to ESRD

“…41 Emerging evidence also suggests that exposure to ambient air pollutants can lead to metabolic disturbances, including glucose intolerance, decreased insulin sensitivity, higher blood lipid concentrations, weight gain, and increased risk of diabetes mellitus. [42][43][44] It is plausible that one or more of these mechanistic pathways may explain the association described here.…”

Exposure to Environmental and Occupational Particulate Air Pollution as a Potential Contributor to Neurodegeneration and Diabetes: A Systematic Review of Epidemiological Research

“…These mostly comprise cohort studies, except for five cross-sectional studies [17,58,59,60,61]. They were conducted in North America (Canada, n = 2 and US, n = 6), Europe (UK, n = 1, Switzerland, n = 2, Denmark, n = 1 and Germany, n = 3), and Asia (Korea, n = 1 and China, n = 2).…”

“…Diabetes status can be measured directly from biomarkers [68], such as fasting blood glucose (FBG), but also because insulin resistance (IR) and inflammation are important hallmarks of T2DM, biomarkers of inflammation, such as C-reactive protein (CRP), are also relevant. Most of the studies in this review used questionnaires and interviews, that collected information on treatment, blood glucose measurements, insulin, leptin, HbA1c, and CRP levels [69,70,71,72], but some studies carried out only blood tests of the above biomarkers [17,58,73], or used both methods [24,59,74]. …”

“…In five studies [24,59,69,71,74] the outcome was measured using both questionnaires, completed by the participants and blood samples taken by them. There were two studies [66,67] based on hospital admission and diagnosis, four studies [32,58,61,73] that relied on samples taken by health specialists and one [60] based on a physical examination.…”

Type 2 diabetes in Asia: where do we go from here?

“…6 Air pollution will initiate and exacerbate a chronic inflammatory state that has effects on the growing foetus and the progression of adult disease. 7,8 Coincident with these environmental and lifestyle changes has been a rapid increase in economic prosperity, unplanned urbanization, a new culture of fast food consumption, and a continued high prevalence of smoking and tuberculosis. 6 The research of Krishnaveni and Yajnik 9 reminds us that maternal nutritional status and metabolic state are equally important.…”