The role of air pollution and lung function in cognitive impairment

Abstract

Air pollution has been associated with impaired lung and cognitive function, especially impairment in visuo-construction performance (VCP). In this article, we evaluate whether the effect of air pollution on VCP is mediated by lung function.We used data from the SALIA cohort (baseline 1985-1994 and follow-up 2007-2010) including 587 women aged 55 years at baseline. Particulate matter (PM) and nitrogen dioxide (NO) exposures at baseline were estimated via land-use regression models. Lung function was characterised by averages between baseline and follow-up. We used age- and height-controlled Global Lung Initiative (GLI) z-scores of forced expiratory volume in 1 s (FEV), forced vital capacity (FVC) and FEV/FVC. VCP was assessed at follow-up with the CERAD-Plus neuropsychological test battery and causal mediation analysis was conducted.An increase of one interquartile range in FEV and FVC was positively associated with VCP (β=0.18 (95% CI 0.02-0.34) and β=0.23 (95% CI 0.07-0.39), respectively). The proportion of the association between NO on VCP mediated by FEV was 6.2% and this was higher in never smokers (7.2%) and non-carriers of the allele (11.2%). However, none of the mediations were statistically significant.In conclusion, air pollution associated VCP was partially mediated by lung function. Further studies on the mechanisms underlying this pathway are required to develop new strategies to prevent air pollution induced cognitive impairment.

Causal Modeling in Environmental Health

“…In 2018, Cole-Hunter et al (18) conducted a regression-based mediation analysis to examine occupational-address noise, residential-neighborhood greenness, and total daily physical activity as possible mediators in the association between PM 10 exposure and cardiopulmonary outcomes. The same year, Huels et al (56) also conducted a regression-based mediation analysis and concluded that the association between air pollution and impairment in visuoconstruction performance (a measure of cognitive function) was mediated by lung function.…”

Air pollution and brain health

“…The authors concluded that a 1µg/m 3 increase in decadal PM2.5 exposure was associated with an increased probability of dementia diagnosis of 1.3% (95%CI 0.4-2.2). The UK investigators using primary care data derived their dementia outcome from the use of Read codes for dementia within the Quality and Three studies reported a measure of cognitive change (based on two measurements) [10,11,14] and one study reported a measure of cognition at one point in time. [15] UK Biobank included several cognitive tests performed on a tablet computer at recruitment: reasoning; reaction time; numeric memory; visuospatial memory; and prospective memory.…”

“…Air pollution data were derived from a single monitoring supersite measuring ambient PM2.5 concentrations and its components which were regarded as tracers for traffic, regional contributions or oil combustion, coal combustion, and crustal PM2.5 sources. [9,11] All the studies used residential address as a proxy for exposure to some extent, but one study used a single air pollution measurement source to assign personal exposure values to everyone in the study. [14] Furthermore, some studies use a very limited period of measurement, for example one year's air pollution data being extrapolated to fifteen years of follow up.…”

“…[1] A number of researchers, notably Dr Lilian Calderón-Garcidueñas, have focused on this area for many years, [2] but the volume of literature has recently been rapidly expanding. So far in 2018 there have been four review articles[3-6] published and another nine scientific articles [7][8][9][10][11][12][13][14][15] which were published too recently for inclusion in those review articles.…”

Benefits of improved air quality on aging lungs – Impacts of genetics and obesity

“…One limitation of our study is the loss to follow-up, resulting in a reduced study sample at the first and second follow-up investigation. Women lost to follow-up were less well-educated, smoked more heavily, were exposed to higher levels of air pollution and their respiratory health was worse than those who participated in the follow-up [36]. These factors have already been shown to be predictors for cardiovascular mortality in the SALIA cohort [20].…”