Abstract
Introduction
Poor childhood conditions can be seen as “the launch pad for a lifetime of health problems” (Raphael, 2011, p. 24). Research consistently shows that growing up under disadvantageous circumstances, such as in poor financial conditions or not living with both parents, is associated with poor later-life health (Gilman et al., 2003; Gruenewald et al., 2012; Kumari et al., 2013; Latham-Mintus & Aman, 2019; Pakpahan et al., 2017). Such experiences may have an immediate impact on the nervous, endocrine, and immune systems that remains apparent in adulthood and later life (Danese & McEwen, 2012). Life course epidemiologists have argued that adversity experienced in childhood may also be harmful for later-life health in an indirect way. Poor childhood circumstances may initiate a
Consistent with the idea of chains of risk, research shows that children who grew up in poor economic circumstances tend to have a lower socioeconomic position as adults (Barboza Solís et al., 2016; Jenkins & Siedler, 2007), which is, in turn, associated with poorer adult health (Barboza Solís et al., 2016; Präg & Richards, 2019; Robert & House, 1996; Whitley et al., 2018). The intergenerational transmission of divorce is also well documented (Dronkers & Härkönen, 2008). People who experienced the divorce of their parents in childhood are moreover relatively likely to become parents at a young age (Quinlivan et al., 2004; Woodward et al., 2004). Divorce and early transitions to parenthood are both, in turn, known antecedents of poor later-life health (Grundy & Read, 2015; Lorenz et al., 2006; Rote, 2017; Sironi et al., 2020).
The current study’s focus is on a potential chain of risk via health lifestyles. Cockerham (2005) has argued that the disposition toward particular health lifestyles is the result of the interplay between
Health behavioral choices within the set of options that are available are also shaped by structural factors via socialization patterns and experiences (Cockerham, 2005). Growing up in poor economic conditions or in a single parent family may be detrimental for the acquisition of cultural capital, that is, the symbolic and informational resources, such as knowledge, values, and norms, that are acquired through social learning (Abel, 2008). People who grew up under such circumstances may thus have relatively poor opportunities for the social learning of healthy lifestyle behavior. Plausibly due to limited life opportunities and exposure to material hardship, people with a low socioeconomic position are relatively likely to view their health as something beyond their control, to think less of the future, and to think less about how they can stay healthy, all of which is, in turn, associated with unhealthy lifestyle choices (Wardle & Steptoe, 2003). Certain forms of unhealthy behavior, such as smoking or drinking, may provide persons with a short-term reduction of the stress associated with having grown up under disadvantageous circumstances, albeit at the expense of a broad range of longer-term health outcomes (McEwen & Stellar, 1993). Growing up in a disrupted family or under poor economic circumstances is furthermore associated with greater impulsivity (Peterson & Zill, 1986), which, in turn, is associated with unhealthy eating, drinking, and smoking behavior (Hofmann et al., 2008).
Adverse health effects of various forms of health behavior may offset or compound each other (Shaw & Agahi, 2012). Therefore, many scholars have recently adopted a holistic perspective on health behavior and considered various aspects of health behavior, such as smoking, drinking, diet, and physical activity, conjointly, rather than in isolation, to provide insights into which behavioral combinations should be prioritized for interventions (Burgard et al., 2020; Griffin et al., 2014; Saint Onge & Krueger, 2017; Shaw & Agahi, 2012). Although research in which multiple aspects of health behavior are combined into an index has provided valuable insights on the antecedents and later-life consequences of health behavior in general (e.g., Barboza Solís et al., 2016; Zaninotto et al., 2020), it should be noted that various forms of health behavior are only weakly associated (Newsom et al., 2005). Many people’s behavioral patterns are discordant, that is, neither uniformly healthy nor uniformly unhealthy (Saint Onge & Krueger, 2017). This suggests that health behavior is a multidimensional concept that cannot fully be captured with an index.
Acknowledging the multidimensional nature of health behavior, the current study uses latent class analysis to distinguish distinct health behavior profiles that vary on the so-called smoking, nutrition, alcohol, and physical activity (SNAP) behavioral dimensions among people aged 50–80 years in Great Britain. It also assesses how disadvantageous early-life circumstances, such as growing up under poor economic conditions or not with both parents, are associated with having particular health behavior profiles and the extent to which effects of disadvantageous early-life characteristics on later-life health is attributable to differences in health behavior profiles.
The outcome of interest is allostatic load, that is, the physiological wear and tear of the body due to repeated or chronic exposures to stressors (McEwen & Stellar, 1993). When people are confronted with stressful challenges, neural, neuroendocrine, and neuroendocrine–immune mechanisms are activated in response. Although beneficial in the short term, this response called allostasis–stability through change–comes with increased physiological wear and tear over time. This long-term damage is called allostatic load. McEwen (1998) has argued that health behavior should be regarded as part of the overall notion of allostasis. This is because suboptimal health behavior, for example, smoking or drinking, may help individuals to cope with stress and challenges in the short term, while being physiologically damaging in the long term (e.g., Barboza Solís et al., 2016; Gruenewald et al., 2012).
Data and Methods
Analytical Approach
Latent class analysis (LCA) (McCutcheon, 1987) will be used to identify distinct health behavior profiles that vary on multiple SNAP dimensions. Health behavior profiles are operationalized here as a latent categorical variable underlying response patterns on a range of survey questions covering different SNAP dimensions. Given that, LCA uses the expectation–maximization (EM) algorithm that may only produce a local rather than the global maximum of the log-likelihood function dependent on the initial parameter values chosen in the first iteration, all latent class models are estimated 250 times with different starting values. A model with two latent classes is first estimated and the number of classes is then increased until the addition of a latent class does not lead to a model fit improvement as indicated by the Bayesian information criterion (BIC) score (Schwarz, 1978). Given the current study’s considerable sample size (see next subsection), BIC is arguably the most appropriate criterion to detect the number of classes because it sufficiently penalizes model complexity to avoid overfitting (Dziak et al., 2020; Tein et al., 2013). The AIC score (Akaike, 1974) is a commonly used alternative criterion to determine the number of classes, but, although it may work well with small samples, it is marred by high overfitting rates in larger samples (Dziak et al., 2020).
After estimating the LCA model with the optimal number of classes, the posterior probabilities of class memberships for each class will be stored for every respondent. Multinomial logistic regression will subsequently be used to predict class membership, whereby uncertainty regarding class membership is taken into account through the use of weights inversely related to the class membership classification errors (Bolck et al., 2004).
Linear regression is used to predict allostatic load. In a first model, allostatic load is regressed on early-life characteristics and a range of contemporaneous controls. The health behavior profiles identified in the LCA are added in a second model. Weights inversely related to the membership classification errors are again used to take uncertainty regarding class membership into account (Bakk & Vermunt, 2016). Bootstrapping is used to estimate the indirect effect of early-life characteristics via health behavior profiles on allostatic load (Preacher & Hayes, 2008).
Sample
Data are from the UK Household Longitudinal Study (UKHLS) (University of Essex, Institute for Social and Economic Research, NatCen Social Research, & Kantar Public, 2018, 2019). The UKHLS is a prospective, nationally representative study. Nurse visits took place in Wave 2, collected between 2010 and 2012. During these visits, physical measures, blood samples, and other health-related information were collected.
Analyses were restricted to 4700 people who participated in both Wave 1 and Wave 2, were aged between 50 and 80 years when Wave 2 data were collected, and had a valid blood sample analytical weight. 51 respondents were dropped because they reported that they did not live with at least one biological parent while growing up. This made it impossible to derive information on childhood socioeconomic circumstances. This exclusion procedure resulted in a final analytical sample of 4649 respondents.
Participation in the UKHLS nurse health assessment was selective. Most notably, no nurse visits were carried out in Northern Ireland. Furthermore, people with particular sociodemographic characteristics (e.g., people who were not married, lower educated, or not born in the UK) were underrepresented. The UKHLS team therefore prepared weights specially for the biomarker data to enable estimation samples to be representative of the general population of Great Britain (Benzeval et al., 2014). These supplied biomarker weights were used in this study.
Measures
Given the analytical approach, three types of measures are distinguished: manifest items, explanatory variables, and the distal outcome. Manifest items are observed realizations of the underlying dimensions of the latent health behavior profiles. The distal outcome is a measure of later-life health predicted by one’s health behavior profile. Explanatory variables considered are background variables that are plausibly predictive of having a particular health behavior profile as well as of allostatic load.
Manifest Items
Six smoking, nutrition, alcohol, and physical activity items were considered. With regard to smoking, current smokers, former smokers, and people who never smoked were distinguished. Two nutrition items were included: one capturing the frequency of fruit consumption and other capturing the frequency of vegetable consumption. Respondents were asked how often they consumed fruit and how often they consumed vegetables in a usual week, with response categories being never, 1–3 days per week, 4–6 days per week, or every day. The two bottom categories were combined into a new category for all respondents who consumed fruit, respectively vegetables, 0–3 days per week because very few respondents reported never eating any fruit or vegetables.
Respondents were also asked how often in the last week they consumed at least one alcoholic drink, and how many types of alcoholic drinks (beer or cider; alcohol shots, wine, and alcopops) they had on the day in the last week on which they drank the most. Alcohol consumption was subsequently converted to alcohol units, with one unit being equal to 10 ml of pure alcohol. Following the guidelines for low-risk drinking agreed upon by the UK chief medical officers (Department of Health and Social Care, 2016), respondents were categorized as nondrinkers, people with low-risk drinking behavior (≤14 units per week), or people with risky drinking behavior (>14 units per week).
Two physical activity items were considered. The question how many days of the past 4 weeks respondents had walked for at least 10 minutes continuously was used to capture the frequency of low-intensity physical activities (cf. Hughes & Kumari, 2017). A distinction was made between respondents who did so on not more than seven of the last 28 days, respondents who did so between 8 and 21 of the last 28 days, and respondents who did so on 22 or more of the last 28 days. A range of moderate-intensity sports were also considered, whereby a distinction was made between respondents who had done sports two times or less in the last year, respondents who had done sports more than twice in the last year, but less than weekly, and respondents who had done sports at least weekly.
Distal Outcome
Allostatic load is a measure of the physiological wear and tear of the body due to repeated or chronic exposure to stressors. McEwen and Stellar (1993), who coined the concept, defined it as “the cost of chronic exposure to fluctuating or heightened neural or neuroendocrine response resulting from repeated or chronic environmental challenge that an individual reacts to as being particularly stressful” (p. 2093). Allostatic load is typically measured with an index of markers of various biological systems (for an overview of various operationalizations, see Johnson et al., 2017). Johnson et al. (2017) recently pointed out that there is no standard method of calculating an allostatic load index in the scholarly literature. What they deemed particularly problematic was the absence of hypothalamic–pituitary–adrenal (HPA) axis biomarkers in the operationalizations of allostatic load in approximately half of the studies they considered in their review. They argued that the absence of HPA-axis markers made the operationalization of allostatic load inconsistent with McEwen and Stellar’s conceptual definition in which the neuroendocrine response to stress was central. However, the UKHLS data used here did include an HPA-axis marker: dehydroepiandrosterone sulphate (DHEA-S). Dehydroepiandrosterone (DHEA) and its sulfate form DHEA-S are the most common steroid hormones in the body and their levels decline with age (Benzeval et al., 2014). In addition to DHEA-S, 12 other markers of cardiovascular (systolic blood pressure, diastolic blood pressure, and resting heart rate), metabolic (waist-to-height ratio, total cholesterol-to-HDL cholesterol ratio, HDL cholesterol, triglycerides, glycated hamoglobin (HbA1c), and insulin-like growth factor-1), kidney liver function (creatinine clearance rate), and immune response (C-reactive protein and fibrinogen) biological systems were included in the allostatic load measure.
Consistent with earlier work (Seeman et al., 2001), all 13 indicators were dichotomized based on quartiles in the weighted sex-specific distributions, whereby scores in the least favorable quartile were coded as one (See Supplementary Appendix A). The dichotomized items were summed into a scale ranging from 0 to 13, with higher scores indicating a poorer physiological condition. The scale’s internal consistency was acceptable (KR-20 = .59).
Explanatory Variables
Early-life characteristics taken into account included whether or not respondents lived with both biological parents when they were 16 years old and whether or not they were born in the United Kingdom. Parental socioeconomic position when growing up was also taken into account. Respondents were asked to list the occupations of their parents when they were aged 14 years, and these occupations were subsequently coded according to the National Statistics Socioeconomic Classification. A distinction was made between parents with disadvantaged (“semi-routine and routine”), intermediate (“intermediate,” “small employers and own account,” and “lower supervisory and technical”), and advantaged (“management and professional”) socioeconomic positions. When the respondent reported that the parent was not working when the respondent was 14 years old, the parent was also coded as having low socioeconomic position. Where the socioeconomic positions of the father and the mother differed, the parental socioeconomic position was coded according to the parent with the highest socioeconomic position.
Early-life health was also considered. Respondents were asked if they were ever diagnosed with any of a range of diseases and health conditions, including diabetes, coronary heart disease, and clinical depression. Respondents who answered affirmatively were subsequently asked at what age they were told that they had this health condition. Respondents who were diagnosed with any of the listed health conditions at the age of 18 years or younger were coded as having health problems when growing up. Diseases most commonly mentioned as being diagnosed with when growing up were asthma and chronic bronchitis.
Sample Characteristics, Means, and Percentages.
Missing Values
The sample included 1636 respondents (35.2%) with missing information on at least one variable of interest. Information on blood pressure (
Results
Four Health Behavior Profiles
A comparison of fit statistics indicated that a solution with four classes fitted optimally with our data (See Supplemental Appendix B). The BIC was lowest when a 4-class solution was chosen. The Akaike information criterion (AIC), which penalizes model complexity much more weakly, showed an “elbow” at the 4-class point, that is, there were only small further AIC declines with the addition of higher-order classes. Figure 1 provides an overview of the class conditional response probabilities on the considered manifest health behavior dimensions. The response probabilities displayed in green represent the class-conditional likelihood of being in the most favorable category in the particular behavioral dimension, respectively: never smoked, daily fruit consumption, daily vegetable consumption, nondrinker, walking for 10+ minutes continuously on 22 or more days out of the last 28 days, and at least weekly sports participation. In contrast, the response probabilities displayed in red respectively represent the class-conditional likelihood of being a current smoker, consuming fruit only 0–3 days a week, consuming vegetables only 0–3 days a week, drinking beyond sensible limits, walking for 10 minutes or more on not more than 7 days out of the last 28, and participating in sport fewer than three times a year. Class-conditional response probabilities.
The latent health behavior profile with the largest prevalence was characterized by a low probability of smoking and a high probability of frequent consumption of fruit and vegetables. Moreover, people with this profile were relatively likely to be physically active as indicated by a high probability of frequent walking and participation in sports. A final feature of this profile that stands out is the high probability of risky drinking behavior and the low probability of nondrinking. This profile was labeled
The second profile also scored favorably on most health behavior dimensions. Fruit and vegetable consumption was high in this profile, and, albeit slightly higher than in the first profile, and levels of smoking were low. Moreover, people with this health behavior profile were highly likely to be nondrinkers. A negative characteristic of this profile was the high likelihood of nonparticipation in sports and of rarely walking for more than 10 minutes continuously. This profile was labeled
The third latent health behavior profile identified was characterized by relatively poor scores on most dimensions. People with this profile were relatively likely to smoke and their consumption of fruit and vegetables tended to be low. As with the second profile, they had a high likelihood of nonparticipation in sports and rarely walked for more than 10 minutes. However, they were considerably less likely to report risky drinking behavior and more likely to be nondrinkers than their counterparts in the first health behavior profile. The label
As with the
Early-Life Circumstances and Later-Life Health Behavior Profiles
Results of Multinomial Logistic Regression Analyses Predicting Class Membership and Average Marginal Effects.
The analyses showed that early-life circumstances predicted later-life health behavior profiles. Compared to people whose parents had high socioeconomic position, people whose parents had a lower socioeconomic position were more likely to have the
The model moreover showed that women were more likely than men to have the
Compared to their highly educated counterparts, people with lower levels of educational attainment were more likely to have the
Allostatic Load
Results of Linear Regression Models of Allostatic Load.
In the second model, the health behavior profiles identified in the LCA were added. People with a
Decomposition of Coefficients of Parental Socio-Economic Position.
Discussion
It is well established that growing up under disadvantageous circumstances, such as in poor financial conditions, is associated with poor later-life health. The current study assessed a potential pathway from early-life circumstances to later-life health via health behavior. Latent class analysis (LCA) was used to distinguish particular health behavior profiles that vary on multiple behavioral dimensions–smoking, nutrition, alcohol consumption, and physical activity (SNAP) – among people aged 50–80 years in Great Britain. Multinomial logistic regression analyses then shed light on how disadvantageous early-life circumstances are associated with having particular health behavior profiles. Finally, the current study assessed to what extent the effects of disadvantageous early-life circumstances on allostatic load–an objective measure of the physiological wear and tear of the body–were mediated by the health behavior profiles identified in the latent class analysis.
Four distinct health behavior profiles were identified among the older British population: (1)
The analyses furthermore showed that people who grew up in a high socioeconomic position family had lower later-life allostatic load than their counterparts who grew up in families with a lower socioeconomic position, and that these differences could to a substantial extent be attributed to differences in health behavior profiles. The lion’s share of the indirect effects of parental socioeconomic position via health behavior profiles was due to people with low and intermediate socioeconomic position parents’ high likelihood to have the health behavior profile associated with the highest allostatic load in later life (
The current study extended earlier work by life course epidemiologists on later-life health by assessing a chain risk between early-life circumstances and later-life health via health behavior, in a way that acknowledged that health behavior is a multidimensional concept. Much earlier work explored chains of risks via socioeconomic circumstances in adulthood (e.g., Luo & Waite, 2005; Surachman et al., 2019), and the few studies that explored chains of risk via health behavior have tended to combine multiple aspects of health behavior into an index (Barboza Solís et al., 2016). Combining multiple aspects of health behavior into an index is, however, at odds with the increasingly dominant view that health behavior is a multidimensional concept. One of the reasons for this is that various forms of health behavior are only weakly associated (Newsom et al., 2005). In line with this argument, a reliability analysis indicated that the six health behavior items considered in the current study did not form an internally consistent scale together (
The main limitation of the current study is that the analyses are cross sectional. Allostatic load was regressed on health behavior profiles, but it is not implausible that health status may also predispose people to a specific health behavior profile. In particular, having a
A second notable limitation is that the information on early-life circumstances used in the current study was collected retrospectively, as were some important control variables. Retrospectively collected information may be of lower quality than prospectively collected information (cf. Sironi et al., 2020) because it may be prone to recall bias. In a recent study, in which prospective and prospective data on British people in their 50s were compared, no systematic differences in the distribution of important early-life characteristics (socioeconomic position of father when growing up and parental separation between birth and age of 16 years) were found, but the authors noted that retrospectively collected early-life characteristics were slightly, but statistically significantly, more strongly associated with later-life health than were prospectively collected early-life characteristics (Jivraj et al., 2020). This suggests that the magnitude of the impact of parental socioeconomic position on later-life allostatic load may be overestimated in the current study.
Recall bias may also explain the considerably higher levels of reported childlessness among men than among women in the sample analyzed here. Rendall et al. (1999) analyzed fertility histories in the British Household Panel Study and the Panel Study on Income Dynamics concluded that between one-third and half of the men’s nonmarital births and births within previous marriages were missed when information on fertility histories was collected retrospectively. Men’s higher levels of reported childlessness in the current study may, however, to some extent also capture the fact that, in couples, men tend to be older than women. Female partners of male respondents are thus typically born later than female respondents. This is important because the median of birth year of female respondents was 1948, and women born in the second half of 1940s form a cohort with a considerably lower prevalence of childlessness than subsequent cohorts of women (Berrington, 2017).
It should also be considered that whereas multinomial logistic regression was used to predict health behavior profiles, the indirect effects of parental socioeconomic position were calculated based on linear probability estimates of class membership (cf. Preacher & Hayes, 2008). However, these linear probability estimates (see Supplemental Appendix C) were very similar to average marginal effects from the multinomial logistic regression model of class membership presented in Table 2.
Older adults’ health behavior patterns tend to be highly stable over time (Burgard et al., 2020), and even after the development of health conditions, people find it difficult to adopt a healthier lifestyle (Newsom et al., 2012). This suggests that efforts to disrupt the chain of risk from early-life socioeconomic disadvantage to poorer later-life health via health behavior may be most promising if they focus on early phases in the life course. Recent reviews suggested that interventions targeting disadvantaged children may yield modest improvements in health behavior among this group (Craike et al., 2018; Wijtzes et al., 2017). However, the body of evidence on which interventions can be based is still very limited considering the need to battle the suboptimal health behavior choices that follow from growing up under disadvantageous circumstances. Wijtzes et al. (2017) therefore recently called for increasing scholarly attention for the long-term effectiveness of interventions aiming to improve health behavior among children growing up under disadvantageous circumstances. The current study’s finding of an important pathway from early-life socioeconomic disadvantage to poorer later-life health via a disposition for suboptimal health behavior underlines the urgency of this call.
Supplemental Material
sj-pdf-1-jah-10.1177_0898264320981233 – Supplemental Material for Early-Life Circumstances, Health Behavior Profiles, and Later-Life Health in Great Britain
Supplemental Material, sj-pdf-1-jah-10.1177_0898264320981233 for Early-Life Circumstances, Health Behavior Profiles, and Later-Life Health in Great Britain by Thijs van den Broek in Journal of Aging and Health
Footnotes
Acknowledgments
Declaration of Conflicting Interests
Funding
Ethics Statement
Supplemental Material
References
Supplementary Material
Please find the following supplemental material available below.
For Open Access articles published under a Creative Commons License, all supplemental material carries the same license as the article it is associated with.
For non-Open Access articles published, all supplemental material carries a non-exclusive license, and permission requests for re-use of supplemental material or any part of supplemental material shall be sent directly to the copyright owner as specified in the copyright notice associated with the article.
