Association between area- and individual-level socio-economic factors with glycated haemoglobin-Evidence from a Portuguese population-based study.

AIMS: This study aims to estimate the associations between area-level deprivation and individual-level socio-economic factors, as well as their interaction, with glycated haemoglobin (HbA1c ) levels. METHODS: We conducted a gamma multilevel regression analysis using individual-level data from the Portuguese National Health Examination Survey and a deprivation index built through factor analysis, at municipality level, with census variables. RESULTS: Living in a municipality with high material deprivation and having a low level of education were independently associated with an increase of 2.3% (95% confidence interval [CI] 0.6, 4.0) and of 1.6% (95% CI 0.6, 2.7) in the mean levels of HbA1c , respectively. The interaction between area material deprivation and individual-level education was not associated with the levels of HbA1c (0.5%, 95% CI -1.3, 2.3). CONCLUSIONS: Our findings support the collective resources model that argues that people in less deprived areas have better health because there are more collective resources. The results suggest that to reduce socio-economic inequalities associated with the levels of HbA1c and, consequently, with diabetes, will require attention to the area material deprivation and individual-level education. Upstream social determinants of health are thus highlighted.

Ambient air pollution and lipid profile: Systematic review and meta-analysis.

Ambient air pollution (AAP) is recognized a cardiovascular risk factor and lipid profile dysregulation seems to be one of the potential mediators involved. However, results from epidemiologic research on the association between exposure to AAP and altered lipid profile have been inconsistent. This study aims to systematically review and meta-analyse epidemiologic evidence on the association between exposure to ambient air pollutants (particulate matter, nitrogen oxides, sulphur dioxide, ozone, carbon monoxide, back carbon) and lipid profile parameters (Total cholesterol; High-Density Lipoprotein Cholesterol; Low-Density Lipoprotein Cholesterol; TG-Triglycerides) or dyslipidaemia. Systematic electronic literature search was performed in PubMed, Web of Science and Scopus databases (last search on 24th May 2019) using keywords related to the exposure (ambient air pollutants) and to the outcomes (lipid profile parameters/dyslipidaemia). Qualitative and quantitative information of the studies were extracted and fixed or random-effects models were used to obtain a pooled effect estimate per each pollutant/outcome combination. 22 studies were qualitatively analysed and, from those, 3 studies were quantitatively analysed. Particulate matters were the most studied pollutants and a considerable heterogeneity in air pollution assessment methods and outcomes definitions was detected. Age, obesity related measures, tobacco consumption, sex and socioeconomic factors were the most frequent considered variables for confounding adjustment in the models. In a long-term exposure scenario, we found a 3.14% (1.36%-4.95%) increase in TG levels per 10 µg/m3 PM10 increment and a 4.24% (1.37%-7.19%) increase in TG levels per 10 µg/m3 NO2 increment. No significant associations were detected for the remaining pollutant/outcome combinations. Despite the few studies included in the meta-analysis, our study suggests some epidemiologic evidence supporting the association between PM10 and NO2 exposures and increased TG levels. Due to the very low level of evidence, more studies are needed to clarify the role of lipid profile dysregulation as a mediator on the AAP adverse cardiovascular effects.