UC Berkeley

Background

Understanding why certain population subgroups age faster than others is a pressing public health concern. Few biomarkers consistently predict morbidity and mortality, which has made it difficult to identify high-risk population subgroups earlier in the disease cascade. Telomeres are the repeat sequence at the ends of DNA that protect the cell from damage during each replicative cycle. Telomeres shorten with age, and individual-level exposures may exacerbate telomere length attrition. There is evidence that telomere length has an inverse association with psychosocial stress, poor health behaviors, and chronic diseases. However, multilevel determinants of telomere length remain understudied despite numerous connections among physical and mental health, lifestyle, and place of residence. The extant literature exhibits that better physical and social contexts have a positive association with telomere length.

Methods

This dissertation examines the associations among specific features of residential built, social, and socioeconomic environments and the 10-year change in telomere length using data from the Multi-Ethnic Study of Atherosclerosis (2000-2010). Chapter 2 presents cross-sectional findings on the relationship between the physical environment and leukocyte telomere length. Chapter 3 investigates the association between changes in physical environment features and the 10-year change in leukocyte telomere length. Chapter 4 explores the interplay among changes in neighborhood socioeconomic status, social context, and leukocyte telomere length. Physical environment features comprise of the physical activity and food environment. The social environment includes measures of aesthetic quality, safety, and social cohesion.

Significance

This dissertation presents the first studies to examine changes in neighborhood features and change in telomere length. The findings suggest that telomere length is a biological marker that is sensitive to changes in built, social, and socioeconomic contexts. Thus, health policy interventions should target specific features of the residential environment to support healthy aging trajectories.