Neighborhood Environment and Epigenetic Age: A Scoping Review

Abstract

Background: Interest in how the neighborhood environment impacts age-related health conditions has been increasing for decades. Epigenetic changes are environmentally derived modifications to the genome that alter the way genes function-thus altering health status. Epigenetic age, a biomarker for biological age, has been shown to be a useful predictor of several age-related health conditions. Consequently, its relation to the neighborhood environment has been the focus of a growing body of literature.

Objective: We aimed to describe the scope of the evidence on the relationship between neighborhood environmental characteristics and epigenetic age.

Methods: Using scoping review following methods established by Arksey and O'Malley, we first defined our research questions and searched the literature in PubMed, PsycINFO, and EMBASE. Next, we selected the literature to be included, and finally, we analyzed and summarized the information.

Results: Nine articles met the inclusion criteria. Most studies examined deprivation as the neighborhood characteristic of interest. While all studies were observational in design, the articles included diverse participants, including men and women, adults and children, and multiple ethnicities. Results demonstrated a relationship between the neighborhood environment and epigenetic age, whether the characteristic of interest is socioeconomic or physical.

Conclusions: Overall, studies concluded there was a relationship between neighborhood characteristics and epigenetic age, whether the characteristic of interest was socioeconomic or physical. However, findings varied based on how the neighborhood characteristic and/or epigenetic age was measured. Furthermore, a paucity of investigations on physical characteristics was noticeable and warrants increased attention.

Keywords: age-related health conditions; epigenetic aging; health disparities; neighborhood; physical environment; socioeconomic status.

Figure 1.

Study search and selection process.

Figure 2.

Neighborhood-level Variables Included in Relationship with Epigenetic Age. Note: Social characteristics were the most frequently reported neighborhood variable, lead by household composition, income, and education.

Figure 3.

Multivariate vs Univariate Measurement of Neighborhood Characteristics Note: Most studies relied on a multivariate index to capture neighborhood environment characteristics.

Figure 4.

Distribution of Epigenetic Clocks Note: The first-generation epigenetic clock developed by Hannum and colleagues was used most frequently to assess epigenetic age.