Damian Sendler: Mental health and physical health are intimately linked, but the exact mechanisms by which they are connected remain a mystery. In a mediation framework, we look at the direct and indirect effects of previous mental health on current physical health and the impact of previous physical health on current mental health. The English Longitudinal Study of Ageing (ELSA) collected data on 10,693 people over the age of 50 in six waves (2002–2012). The Centre for Epidemiological Studies Depression Scale (CES) is used to assess mental health, while the Activities of Daily Living (ADL) is used to assess physical health (ADL). Direct effects account for 10% of the effect of past mental health on physical health, and indirect effects account for 8% of the effect of past physical health on mental health. Indirect effects are largely due to physical activity. Males (9.9 percent) and older age groups (13.6 percent) have greater indirect effects on mental and physical health (12.6 percent ). Mental and physical health are intertwined, and health policies aimed at improving one or the other must take this into account both directly and indirectly.
Damian Jacob Sendler: Common mental illnesses are becoming more prevalent among the populations of Western industrialized countries (Twenge et al., 2010, Hidaka, 2012). There is a strong correlation between physical and mental health (Nabi et al., 2008, Surtees et al., 2008). Even after controlling for confounding variables, Ohrnberger, Fichera, and Sutton (2017) found strong cross-effects between physical and mental health. There is still a lack of understanding of the possible “indirect effects” that mental and physical health have on each other. The development of health policies could benefit greatly from an understanding of these indirect effects and how they differ between population groups.
Dr. Sendler: For the older population’s physical and mental health to be more closely linked, the authors of this paper propose a mediation framework and estimate the mediating effects of lifestyle and social capital. The research is based on the economics of health care, which considers both the production and consumption of health care services. For older people, health policies must take into account factors like lifestyle and social capital, which have a direct impact on their well-being (Artaud et al., 2013; Holt-Lunstad et al., 2012). According to a study by the Ageing Research Group (Melzer et al., 2012), lifestyle changes in high-income countries could prevent approximately 55% of the disease burden experienced by people 60 and older. Lifestyle factors account for up to 70% of disease burden in the general population (WHO, 2009). Inclusion, exclusion, and social isolation all contribute to a person’s social capital. With low-cost interventions, these are strong risk factors for ill health and pose a high risk to the health of older populations (Steptoe et al., 2012).
Damian Sendler
Our research examines the interplay between the physical and mental well-being of the elderly in the United Kingdom, looking at both the direct and indirect effects of previous mental health. ELSA (2002–2012) longitudinal data are used in this study, which includes six waves of data. Following Ohrnberger et al., we model the current level of one form of health as a function of the stock of the other form of health for direct effect estimations (2017). Individuals’ lifestyle choices (such as how much they exercise or smoke cigarettes) and social capital are used to model the indirect effects (social interaction). A multivariate regression framework is then used to calculate total differentials, which are changes in the function of variables dependent on changes in another variable in order to estimate direct and indirect effects. Comparable to the method utilizing the product of coefficients (Baron and Kenny, 1986, MacKinnon et al., 2007).
Mediation analysis has been used in many psychological, epidemiological, and economic studies, but not in our context. In a number of these studies, researchers have examined the direct and indirect effects of anxiety and childhood traumas on the mental health of people (Turner and Butler, 2003, Dour et al., 2014). Mental health has also been studied as a mediator between quality of life and employment outcomes (Wong et al., 2010, Johar and Truong, 2014). A third group of studies has examined the role of health investments in influencing labor outcomes and the quality of life of workers (Han et al., 2011, Wicke et al., 2014, Bekele et al., 2015 Burns et al., 2015).
First and foremost, we find that past physical and mental well-being has both direct and indirect consequences on the current state of physical or mental well-being. As in both models, the indirect effect accounts for about 10% of all effects and is mostly explained by one’s prior level of physical activity. Subgroup estimates show a wide range of effects based on age and gender. The results are unaffected by the timing of the mediators or the model used to estimate the amount of addiction.
Damian Jacob Markiewicz Sendler: Individuals can reap both consumption and production benefits from their health, according to Grossman (1972). Leisure activities can only be enjoyed if you have enough time to do them. Healthy time is an investment that pays dividends in the form of money. It is possible to either consume or produce health through the use of medical treatment and/or a variety of dietary and lifestyle choices (Grossman, 1972). Theories of health since Grossman have included additional factors such as retirement, early childhood investments and endowments and stress, as well as social capital and socio-economic status as determinants (Bolin. et al., 2003, Galama and van Kippersluis, 2013).
For starters, work can have an effect on both physical and mental health. As a result of poor health (physical or mental), people may not be able to afford healthy food and environments. Mental and physical health are negatively impacted by this income effect. Sleep deprivation and stress at work can also have negative health effects on people with mental health issues (Contoyannis and Rice, 2001, Garca-Gómez et al., 2013).
It is also possible that people’s mental health can affect their ability to make informed decisions about their healthcare, which can have a negative impact on their physical health (Mani et al., 2013).
Third, lifestyle choices such as physical activity, smoking and alcohol consumption, and a healthy diet are linked to both physical and mental health (Stampfer et al., 2005, World Health Organization Global Health Risks, 2009). A number of studies have found a link between depression/anxiety disorders and poor physical health and a lack of physical activity (Gerber and Puehse, 2009, De Mello et al., 2013, Durstine et al., 2013, Wang et al., 2014, Hegberg and Tone, 2015). Exercise has a positive impact on both mental and physical health outcomes in older adults, according to systematic reviews (Forbes et al., 2008, Clegg et al., 2012). People who are in better physical and mental health are also more likely to engage in physical activity, suggesting a possible reverse-causal relationship. After smoking cessation interventions, depression, anxiety, and stress were all found to be reduced in a systematic review by Taylor et al. (2014). Smoking is more than twice as common in depressed or anxious adults, suggesting that the two may be connected in a causal way (RCP, 2013).
Dr. Sendler: Researchers have discovered that moderate alcohol consumption is linked to better mental and physical health, and that higher levels of mental and physical well-being are predictive of lower levels of alcohol consumption (Stampfer et al., 2005, Lang et al., 2007). Drinking too much or abstaining from alcohol has a negative impact on health and is associated with worsened physical and mental health (Rehm et al., 2010, Frisher et al., 2015). Another significant lifestyle choice that affects health production is one’s diet. A higher mortality risk is linked to a poor diet (Haveman-Nies et al. 2003). When it comes to happiness, Mujcic and Oswald (2016) found that people who eat a lot of fruit are happier.
Finally, the importance of social interactions in health cannot be overstated. Social interaction has been shown in previous research to have a positive impact on mental health (Dour et al., 2014, Bekele et al., 2015). While controlling for baseline mental and physical health, researchers have discovered that loneliness and social isolation are both linked to an increased mortality risk (Steptoe et al., 2012). A systematic review by Holt-Lunstad et al. (2012) shows that social relationships have a significant impact on mortality risk. There have also been findings in the literature that physical disability and poor mental health can lead to isolation, as well as the opposite (Steptoe et al., 2012).
Damian Jacob Sendler
As a starting point for our mediation analysis, we use this conceptual framework. For the following reasons, we believe physical activity, smoking, and social interactions are the most important mediating factors in the relationship between mental and physical health. Predicting mortality is a primary function of these mediators. Smoking is a major contributor to premature death in the United Kingdom (Office for National Statistics UK, 2016). Physical inactivity accounts for 7.7% of all deaths, while tobacco use accounts for 17.9% of deaths (WHO, 2009). A lack of social capital also raises the mortality risks associated with aging populations due to social isolation, loneliness, and exclusion (Holt-Lunstad et al., 2012, Melzer et al., 2012, Steptoe et al., 2012). Mortality is less dependent on other potential mediators. As an illustration, only 4.1% of deaths can be attributed to factors such as alcohol consumption or dietary choices (WHO, 2009).
Second, our mental health metric captures factors like stress and sleep deprivation directly. Another factor that is frequently used in the literature as a measure of health outcomes is obesity, high blood pressure, and alcohol consumption (Banks et al., 2006). Drinking alcohol is more of an indicator of good mental and physical health than an input factor, according to Holdsworth and colleagues (2016). It is important to note, however, that only 59 percent of our sample is employed. The measurement of other mediators in our dataset is also a concern. From wave 5 onwards, questions about dietary preferences began to be included in the ELSA, but only in the third wave.
This is why our estimates are considered lower bounds on the indirect and direct effects of physical and mental health.
8 percent of the total effect on mental health and 7.5 percent of the total effect on physical health are explained by physical activity. Physical activity has a positive effect on both physical and mental health because it is associated with better physical and mental health. People who are more active are more likely to be physically fit, which has a positive effect on their mental and physical health. A positive correlation between mental health and physical activity has been discovered by Gerber and Puehse (2009).
Positive effects on mental and physical health can be traced back to previous social interactions. It accounts for roughly 13.6% of the total indirect effect on physical health. Social support has been linked to better mental health in the past (Umberson and Montez 2010). The link between mental and physical well-being has previously been shown to exist. According to this theory, social interactions encourage healthy behaviors and vice versa (Umberson et al., 2010).
Cigarette smoking is associated with a lower level of mental health in the past, which in turn has a positive impact on current physical health. Compared to the English population without mental health disorders, Szatkowski and McNeill (2015) found a more than doubled smoking rate among the English population with mental health disorders.