Air pollution linked to depression and cognitive decline in older women; claims study
A recently published research in the Journal of the American Geriatrics Society has highlighted on the fact that exposure to air pollution can lead to depressive symptoms, as well as episodic memory decline among older women. This manuscript was presented at the 2020 Virtual Annual Meeting of the International Society of Environmental Epidemiology in Washington, D.C
Exposure to air pollution may contribute to both increasing depressive symptoms and decreasing episodic memory in older adulthood, but few studies have examined this hypothesis in a longitudinal context. Growing evidence has emerged that exposure to polluted air is associated with impaired cognitive functions at all ages and increased risk of AD and other dementias in later life; this association is particularly notable with traffic related pollutants such as nitrogen dioxide, nitrous oxide, black carbon, and small diameter airborne solids and liquids known as particulate matter. The exact mechanisms by which air pollutants mediate neurotoxicity in the central nervous system (CNS) and lead to cognitive decline and AD remain largely unknown.
Taking a cue from this,researchers examined the association between air pollution and changes in depressive symptoms (DS) and episodic memory (EM) and their interrelationship in oldest‐old (aged 80 and older) women.
For h study design ,Prospective cohort data from the Women's Health Initiative Memory Study‐Epidemiology of Cognitive Health Outcomes was taken into account.
A total of 1,583 dementia‐free women aged 80 and older were taken as the sample population.
Women completed up to six annual memory assessments (latent composite of East Boston Memory Test and Telephone Interview for Cognitive Status) and the 15‐item Geriatric Depression Scale (GDS‐15). Researchers estimated 3‐year average exposures to regional particulate matter with aerodynamic diameter below 2.5 μm (PM2.5) (interquartile range [IQR] = 3.35 μg/m3) and gaseous nitrogen dioxide (NO2) (IQR = 9.55 ppb) at baseline and during a remote period 10 years earlier, using regionalized national universal kriging.
On data analysis, the following facts emerged.
- Latent change structural equation models examined whether residing in areas with higher pollutant levels was associated with annual changes in standardized EM and DS while adjusting for potential confounders.
- Remote NO2 (β = .287 per IQR; P = .002) and PM2.5 (β = .170 per IQR; P = .019) exposure was significantly associated with larger increases in standardized DS, although the magnitude of the difference, less than 1 point on the GDS‐15, is of questionable clinical significance.
- Higher DS were associated with accelerated EM declines (β = −.372; P = .001), with a significant indirect effect of remote NO2 and PM2.5 exposure on EM declines mediated by DS.
- There were no other significant indirect exposure effects.
For the full article follow the link: https://doi.org/10.1111/jgs.16889
Primary source: Journal of the American Geriatrics Society