Despite the growing need for mobility, the anthropogenic byproducts of transportation, construction, and other human activity within our built environments, such as air pollution and noise, are detrimental to human health. In the United States (US), environmental noise is a ubiquitous yet overlooked pollutant and source of physiological and psychological stress. Several studies have examined associations between environmental noise and health outcomes, particularly in Europe; however, an insufficient number of longitudinal studies have been conducted. Additionally, much of the research lacks individual-level data, sufficient adjustment for confounding, and the ability to establish temporality. With an increasing demographic shift of the US population to an older age profile, there is heightened imperative to examine new interventions to reduce chronic disease risk, specifically upstream factors associated with risk factors for cardiovascular disease (CVD) and dementia, at the population level. The objective of this dissertation was to investigate the potential effects of long-term environmental noise exposure on CVD and dementia-related outcomes in the US by leveraging data from nationwide (Nurses’ Health Studies, Chapter Two) and local (Chicago Health and Aging Project [CHAP], Chapters Three and Four) cohorts. In both cohorts, annual aircraft noise estimates obtained from the Aviation Environmental Design Tool were generated every five years from 1995 to 2015 and linked to participants’ geocoded addresses. In CHAP, annual community and road noise estimates were generated within the Chicago city boundaries from separate land-use regression and CadnaA noise propagation models, respectively, for the same period as our aircraft noise estimates (1995 to 2015). In Chapter Two, we examined associations of aircraft noise with CVD incidence, CVD mortality, and all-cause mortality in the nationwide Nurses’ Health Studies, consisting of two prospective cohorts of 121,700 (Nurses’ Health Study, NHS) and 116,686 (Nurses’ Health Study II, NHSII) female nurses followed over the past 40 years. Overall, we did not find associations of aircraft noise with our outcomes of interest, which may reflect the lack of variability estimated exposure, as only approximately 7% of individuals experiencing a CVD-related event or death were exposed to aircraft noise above 50 A-weighted decibels. In Chapter Three, we assessed the relations of various types of environmental noise (community, road, aircraft) with three blood biomarkers of neurodegeneration (total tau, t-tau; neurofilament light chain, Nf-L; and glial fibrillary acidic protein, GFAP) in CHAP, a local prospective cohort of older adults living in Chicago, Illinois. We observed weak adverse associations of community, road, and aircraft noise with t-tau and Nf-L, which suggest that noise may work directly through neuronal damage. With GFAP, we observed weak and imprecise protective relations with GFAP, which may indicate that astrocyte activation may not be a pathway in which noise impacts health. Lastly, in Chapter Four, we continued to use data from CHAP to quantify associations of each noise measure (community, road, aircraft) with baseline cognitive performance, cognitive decline, and Alzheimer’s dementia (AD) incidence. In this study, we operationalized cognitive level and decline using assessments of perceptual speed, episodic memory, and a global cognitive performance score. With community and road noise, we found associations between increasing noise level and worse performance on each cognitive domain at baseline; however, we did not observe any associations with cognitive decline. With aircraft noise, we found mixed associations with cognitive performance at baseline, in which we unexpectedly observed some increasing aircraft noise categories with better cognitive performance, particularly with episodic memory. Yet, higher exposure to aircraft noise corresponded to faster rate of cognitive decline over time, most notably among the highest (versus the lowest) exposure category. When examining each noise source with cumulative odds of AD, we found suggestive yet imprecise associations, indicating greater odds with increasing exposure. Overall, our results should be interpreted cautiously, as the confidence intervals for the estimates were wide, and estimates were not necessarily consistent across sources of noise exposure. Although many of the results consistent with no association, this dissertation adds to the sparse literature on noise and health in aging populations and establishes a foundation for developing research on these questions that is more robust. / 2026-05-10T00:00:00Z

Background: Alzheimer???s disease and related dementias (ADRD) are often improperly or under-diagnosed in primary care; yet, it is expected that community-based care will be an increasingly important source of support for ADRD patients. In Ontario, primary care has continued to expand its services to include health team models, such as family health teams (FHTs) to provide multidisciplinary collaborative care for patients. Within such teams, memory clinic teams have also been implemented, which are clinic days set up typically once or twice a month to provide interprofessional collaborative care specifically for ADRD patients by trained health care providers (HCPs). Objective: Little is known about the experience of HCPs who work in primary care memory clinic team settings to provide care for ADRD patients. This study explored these experiences. Specifically, questions were asked around the rewards, challenges and motivations with working in the memory clinic structure and providing support to ADRD patients. Methods: A phenomenological approach was used. One-on-one semi-structured interviews were completed with 12 interprofessional team members in two primary care memory clinic teams. Interviews were transcribed and analyzed using Colaizzi???s (1978) method of analysis. Results: Overall, seven subthemes were found which describe the HCP experience. The first two subthemes describe experiencing the journey with the patient and caregiver. HCPs want to support patients while maintaining the patient???s dignity. They also balance emotional dilemmas with responsibilities. The next two subthemes describe experiencing the journey with the team. HCPs feel valued and connected to their team members. The memory clinic structure offers unique care provider experiences. Lastly, three subthemes were found which describe the personal and professional rewards of the experience. HCPs found thrilling complexities within the patient population in the memory clinic and that working in the clinic they are able to experience ongoing learning opportunities. HCPs also described that the memory clinic offers personal and professional fulfillment. Discussion: HCPs described an overall positive experience working in the memory clinic to support ADRD patients. HCPs take pride in being able to support patients and caregivers. Knowing that they are making a difference and doing good work are motivations to continue to work with complex populations, such as ADRD patients. HCPs enjoy working in close proximity to one another, respect their team members, and enjoy learning from each other. Team members motivate each other to stay and work with the ADRD population in primary care memory clinics. HCPs reap many rewards associated with working in a ???tight-knit??? memory clinic team setting for ADRD patients. As the number of HCPs working in team settings continues to grow in Canada, it is important to look at the experiences of these teams to understand the rewards, challenges and motivations of team members. Conclusions: These findings provide more context in understanding how to motivate future HCPs to work with more complex populations such as ADRD patients. Future research should address the outcomes of these clinics by exploring patient and family caregiver experiences with specialized teams, as it is important to gain their experiences to enhance the care practices for these individuals.

Biologisk ålder (BA) har nyligen fått ökad uppmärksamhet att fördjupa förståelsen kring åldersrelaterade sjukdomar och dess behandlingar, eftersom åldersrelaterade förändringar utgör en grundläggande gemensam nämnare för dessa tillstånd. Medan kronologisk ålder (CA) mäts i år, kan biologisk ålder (BA) mätas på många olika sätt. I det här mastersarbetet användes blodbaserade biomarkörer som korrelerar med CA för att skapa uppskattningar av BA, med algoritmerna ‘PhenoAge’, ‘Klemera-Doubal metoden’ och ‘Homeostatic Dysregulation’. Biomarkörerna valdes ut genom Pearson och Spearmankorrelation med CA separat för varje kön. Dessutom validerades biomarkörerna mot mortalitet. Kohorten AMORIS (Apolipoprotein-relaterad dödlighetsrisk) användes för att beräkna tre olika biologiska åldersmått med hjälp av BioAge-paketet. För att undvika kollinearitet användes residualerna från dessa biologiska åldersmått, som representerar avvikelsen av BA från CA. PhenoAge-residualerna valdes för vidare undersökning på grund av deras robusthet. Sambandet mellan BA-residualer, särskilt PhenoAge-residualer, och Alzheimers sjukdom och relaterade demenssjukdomar (ADRD) utvärderades med Cox proportionella hazardmodeller. Justeringar gjordes för kön, utbildningsnivå och socioekonomisk status. Stratifiering för två åldersgrupper, över 65 och under 65, samt kön utfördes för två olika modeller. Modellens överensstämmelse varierade, över lag var den bättre för vaskulär demens och sämre för Alzheimers sjukdom. En ökad riskkvot hittades särskilt för vaskulär demens (PhenoAge HR=1.086, 95% CI=1.074 to 1.099), och till viss grad även för andra demenstyper men inte för Alzheimers sjukdom. Stratifiering efter ålder och kön visade varierande hazardkvoter, vilket tyder på olika riskprofiler bland olika demografiska grupper. En ökad risk för vaskulär demens noterades särskilt i åldersgruppen under 65 och bland män. Dessa differentierade risker belyser vikten av BA-markörer för att identifiera ökad risk för demensundergrupper och bekräftar värdet av att inkludera BA i bedömningen av ADRD för användning inom precisionsmedicin. / Biological age (BA) has recently gained increased attention as a means of deepening the understanding of the development of treatments for age-related diseases, as age-related changes serve as the fundamental commonality among these conditions. While chronological age (CA) is measured in years, BA can be measured in a wide variety of ways. In this thesis blood biomarkers correlated with CA were used as input to create BA estimates, with the algorithms PhenoAge, Klemera-Doubal method and Homeostatic Dysregulation. The serum biomarkers were selected by Pearson and Spearman correlation with CA separately per sex. The cohort AMORIS (Apolipoprotein-related MOrtality RISk) was used to calculate three different BA scores with the help of the BioAge package. To avoid collinearity, the residuals from these BA scores, which represent the deviation of BA from CA, were employed. The PhenoAge residuals were selected for further investigation due to their robustness. Association between BA residuals, particularly PhenoAge residuals, and Alzheimer’s disease and related dementias (ADRD) was assessed using Cox proportional hazard models. Adjustment was done for sex, education level and socioeconomic status. Stratification for two age groups, over 65 and under 65, as well as sex was done for two different models. The model concordance varied, overall, it was better for vascular dementia and worst for Alzheimer's disease. An increased hazard ratio was found especially for vascular dementia (PhenoAge HR=1.086, 95% CI=1.074 to 1.099), and to a lesser extent for other dementia types but not for Alzheimer's disease. Stratification by age and sex presented varied hazard ratios, suggesting different risk profiles among demographic groups. An increased risk for vascular dementia was especially noted in the age group under 65 and men. These differentiated risks, highlight the importance of BA markers in pinpointing elevated risks for dementia subtypes and affirm the value of incorporating BA into the assessment of ADRD for use in precision medicine.