Lifetime cumulative adversity and physical health deterioration in old age: Evidence from a fourteen-year longitudinal study

Highlights

• Evaluated a 14-year growth model of cumulative adversity and late-life physical health.

• Used Survey of Health, Ageing and Retirement in Europe as database.

• Higher cumulative adversity was related to an accelerated decline in health.

• The effects on mobility limitation were stronger than self-rated health.

Abstract

Background

Although several studies have demonstrated the associations between lifetime cumulative adversity and late-life physical health, many of them were conducted at a single time point and examined events that occurred in childhood only. Less is known about the effect of lifelong adversity on the aging process over time. This study aimed to investigate the impact of cumulative adversity on the accelerated deterioration in health over time - mobility limitation and self-rated state of health in old age.

Methods

This study provides a 14-year, 6-time-point follow-up on a representative sample of Europeans using the SHARE Project - longitudinal survey panel. The sample included a total of 7195 respondents aged 65 and older from nine countries in Europe. The outcome measurements were the number of mobility limitations and self-rated health – trajectories along 6 measurements. The independent variable was Lifetime Cumulative Adversity, and the analyses included also control variables – age, gender, socioeconomic status, depression, and country.

Results

Time-based Latent Growth Curve Modeling has demonstrated that the effects of Lifetime Cumulative Adversity were significant on both health measures, by means of the intercepts and the slopes: Greater experience of adversities correlated with a higher physical health impairment at baseline and a higher decline along time. The effects of self-rated health were weaker than the effects of mobility limitations.

Conclusions

Given that the populations of numerous countries are rapidly aging, understanding the risk factors associated with health deterioration is important, especially for policymakers and medical health care experts, to raise awareness of the relationship between lifelong adversity and health decline and to build preventive interventions to deal with these consequences.

Introduction

The increase in the aging population is a relatively new global phenomenon, accompanied by high rates of illness and decline in health. In recent years, researchers have investigated risk factors for the accelerated deterioration of health in old age. Cumulative stress is one of the mechanisms responsible for this process, according to inequality theory (Ferraro and Shippee, 2009). The theory argues that personal trajectories are shaped by the accumulation of risk and resources, and that accumulation of stress, as a risk factor, may lead to biological changes commonly associated with the aging process. According to the theory, people who have had severe adversity and stress in their lives would be more susceptible to early mortality and illness in their adulthood, especially in old age. A growing body of research has likewise shown that chronic stress can adversely affect the human body in a dose-response pattern: the more frequent the system activation is, the graver the physiological consequences will be (Epel, 2009; Epel et al., 2006; McCrory et al., 2015; Rasmussen et al., 2020).

Inequality theory is consistent with another major theory explaining the accumulation of stress in old age. The Conservation of Resources (COR) model (Hobfoll, 1989, 2002) suggests that people deal with stress by retaining or obtaining resources. According to this theory, stress occurs when central or key resources are lost, or when significant efforts to gain central or key resources fail. From the perspective of accumulation, stressful events can cause a dilution of resources, leading in turn to a shortage in resources for dealing with future stressful events. Cumulative stress, therefore, may be more determinative than a single stress event, due to the loss of resources over time.

COR theory is closely aligned with inequality theory from the perspective of life span development. Similar to inequality theory, the COR model defines aging as a distinct life stage. During aging, the consequences of lifetime cumulative stress can be more substantial than at younger ages, as a result of a decrease in resources and of biological changes in this period. COR theory focuses on gain and loss of resources and the inevitable depletion of resources that accompanies aging, which, in turn, demands a realignment of available resources to compensate for failing ones (Hobfoll and Wells, 1998).

A large body of evidence supporting some of the above assumptions suggests that negative life events are risk factors for stress reactions and that there is an association between cumulative adversity and poor physical health in old age. A recent study modeled the possible factors contributing to stress and its consequences, and demonstrated a large body of evidence linking adversity to mental and physical health throughout life (Nelson et al., 2020). For example, McCrory et al. (2015) found positive associations between cumulative childhood adversity (e.g., substance abuse among parents, physical abuse) and old-age diseases, in line with a dose-response pattern: adults who reported more childhood adversities were at higher risk of chronic cardiovascular disease and mental, neural, or psychiatric illness. Taylor et al. (2019) found that early-life military exposures have a positive effect on functional limitations and activities of daily living limitations in old age. Gruenewald et al. (2012) demonstrated that more socioeconomic-related adversities in childhood may lead to problems in later life in seven different physiological systems, among them the nervous system, cardiovascular system, and metabolism. Other studies pointed to relationships between cumulative adversity and dementia, cardiometabolic disease, difficulty in daily living activities, and other physical problems and medical diagnoses (Donley et al., 2018; Jakubowski et al., 2018; Radford et al., 2017; Riem and Karreman, 2019; Stesssman et al., 2008).

One point should be noted. Both COR and inequality theories suggest that the impact of cumulative stress is relevant throughout the life cycle, not only during aging, but they still define aging as a unique period during which cumulative inequality and loss of resources are increased. However, old age is not a singularly homogeneous period. Some studies found that inequality tends to increase with age, with higher inequality levels present after age 65 (Crystal et al., 2017; Prus, 2007). Additionally, several studies on trauma and stress have targeted older adults (65+) for their study population, as a specific group within aging that is more vulnerable to the consequences of stress (e.g., Inoue et al., 2021; Raposo et al., 2014; Traviss-Turner et al., 2016).

The current study addresses the notion of lifetime cumulative adversity (LCA) capturing a life-span perspective on accumulated exposure to a wide spectrum of potentially traumatic events throughout all periods on life (Turner and Lloyd, 1995). Although LCA has been found to be associated with physical health problems in old age, various issues have yet to be addressed in research. First, existing examinations have intensively probed the impact of accumulation of childhood events on old-age health, but the effect of LCA on trajectories of older age health has been studied only to a limited degree. Second, most studies used a cross-sectional approach, whereas other studies lasted only a few years—not the long-term exploration one would expect for a process taking place over decades. Several studies that did combine the two issues showed that lifetime adversity is related to trajectories of health over time (e.g., Comijs et al., 2011; Seery et al., 2010). The longest longitudinal studies to have examined the relationship between LCA and health deterioration during aging over time examined the association for a period of up to six years. They found a higher decline in physical and mental indicators over three time points— during four years (Shrira, 2012), and accelerated deterioration in physical function over four time points during the six years (Shrira and Litwin, 2014).

The current study extends previous studies by investigating the association between LCA and physical health over fourteen years with six time points. Using a large representative sample from the Survey of Health, Ageing and Retirement in Europe (SHARE), we estimated the health deterioration in adults aged 65 and older. Although the prevalence of specific adversities varied between regions or countries, overall, people reported similar proportions of adversities in different regions (Kessler et al., 2010). The value of a cross-national survey like SHARE is its ability to reflect the global nature of various phenomena as lifetime adversities (Kessler et al., 2010).

Whereas there are several methods for conceptualizing health, it is acceptable to refer to self-assessment of health as an inclusive reliable measurement (Cox et al., 2009; DeSalvo et al., 2006). In addition, mobility limitations were found in previous investigations to be a sensitive indicator for health changes specific to old age (Darin-Mattsson et al., 2017; Wahrendorf et al., 2013). Demographic variables such as age, gender, and socioeconomic status (SES), as well as mental health, are well-established background factors associated with old-age health (Darin-Mattsson et al., 2017; Makaroun et al., 2017; Ohrnberger et al., 2017; Zimmer et al., 2016). In understanding the association between LCA and health, it is essential to investigate whether the observed associations have an impact beyond these other background factors. The hypothesis of the present study was that the long-term study, after controlling for background variables, would demonstrate the association of LCA with health deterioration.