Psychological Aging Clocks: a Measure of Emotional Health and Well-being?

"How old would you be if you didn't know how old you was?" (Satchel Paige)

Looking at the bright side of the medal, aging brings wisdom, experience, temperance, and a bag of memories. Unfortunately, however, age is also associated with progressive cognitive and physical decline, which in some cases may exacerbate chronic and neurodegenerative diseases.

In previous articles, I have discussed how aging, in its biological process, may deviate from its normal trajectory, manifesting the onset of pathologies, such as dementia and Alzheimer’s disease (AD). Alzheimer’s and dementia is recognized as one of the most common diseases and the sixth leading cause of death in the U.S. Therefore, besides the progressive decline of learning, memory, and physical activity, emotional well-being is affected which requires a closer look because it is highly connected with cognitive and physical functioning.

Thus, in this article, I discuss the importance of healthy aging with a focus on the psychology of aging, and how psychological intervention in older age would promote health outcomes, life quality, and satisfaction. Moreover, while a strong predictor of health is found to influence biological aging, AI-based “psychological aging clocks” are presented, highly linked to health longevity and mental health, potentially aging reversers.

How do we age?

Fragile and grumpy? Wrinkles and greying hair? It’s all about genes? Thinking of aging and older adults, this is the image that most probably tends to be attributed, but it does not reflect the reality. Indeed, older people are better capable of regulating emotions, more conscientious, and agreeable. In addition, elders are happier, more mellow, grateful, and have a flexible mindset than midlife individuals. Last but not least, nowadays elders declare a better wealth and health status, and higher education compared to older people of past decades. However,  aging is a fact and cannot be neglected. Accordingly, aging is a multifactorial process in which the body and at the higher level, also cognitive functions are affected. Thus, a series of biological and physiological processes are involved which are prone to progressively decline. A few studies have already shown that a lower subjective age is related to higher psychological and physical health, cognitive abilities, wellbeing, and more generally life satisfaction [1].

Based on a US Census, by 2060 one-quarter of the population will be 65+ years old. Therefore, closer attention should be focused on well-being and mental health in later years of life. Particularly, improving cognitive decline, usually observed in dementia and Alzheimer's disease (AD), and physical health due to progressive motor disabilities and physical inactivity, became the major areas of interest when investigating aging (and related impairments) to promote health and a better quality of life. Moreover, the increased focus on improving the quality of care delivery services and a closer investigation of age-related cognitive and physical dysfunctions had the positive effect of having older individuals aged 65 or even older reporting fewer debilitating disorders, impairments, living in nursing homes, or in assisted-living arrangements. Besides, an increase in lifespan is also observed. Indeed, men are expected to live to around age 83, while women to age 85.

What is healthy aging?

What is aging? In the health longevity article series, I discussed how aging can hardly be differentiated from longevity because the rate of aging can influence lifespan, although researchers debate the fact that lifespan and longevity are two processes that occur independently of aging and healthspan.

Thus, due to the increased life expectancy and the development of age-related health issues, modern medicine has greatly evolved toward regenerative and longevity medicine, the core research of the booming longevity industry, aimed at reversing the aging process while improving physical and cognitive functioning. The “mind-body” connection is not a myth but is provided to be highly interconnected and interdependent to foster health throughout the lifespan. Besides, health longevity or healthy aging is also the result of multiple habits earlier in life that make the difference later in life. Indeed, recent research showed that by comparing physically active younger adults aged 20 and 30 years with those who did not practice regular activities, had stronger cardiovascular and cognitive functioning in mid-life and 25 years later.

Furthermore, being mentally active to maintain cognitive abilities is demonstrated to be a protector against AD development, and has been called cognitive reserve. Besides, a focus on stimulating well-being through self-care, healthy diet and habits, and high-quality social relationships/support are also key factors to healthy aging because determining lower levels of stress, lower mortality risk (by almost 50%), and thus higher life quality and satisfaction.

Despite the importance of targeting cognitive and physical functioning, also emotional health should be prioritized when promoting healthy aging. Indeed, emotional and physical health are strictly connected, influencing each other. It is common to talk about loneliness, depression, and anxiety, often occurring and affecting the older population, and possibly due to the vulnerability of their mental health status. Nevertheless, although mental conditions are treatable, often older individuals are untreated, or even worse undiagnosed, thus collapsing the healthcare economy due to higher costs (the case of the U.S.). For example, loneliness is very common, and more than a third of adults aged 45 or even older report feeling (chronically) lonely. Social isolation also contributes to anxiety, depression, stroke, heart disease, type-2 diabetes, cognitive abilities, and consequently raises the risk of dementia. In addition, contrary to the general misinformation, depression should not be treated as a normal process and event happening in aging, but as an obstacle to be faced and treated in advance. Likewise, severe anxiety has negative effects on daily living, but also it has the effect of shortening the length of the telomeres (the end caps of chromosomes) leading to cell death and a faster aging process.

Why invest in the psychology of aging?

As previously mentioned, a great segment of the U.S population is 65+ years old. Despite most of them reporting good mental health conditions, it cannot be neglected that a considerable number of elders encountering physical and mental (e.g. anxiety, depression) difficulties will almost quadruple, from 4 million in 1970 to 15 million in 2030. Thus, interventions and treatments to address these conditions would improve mental health and reduce emotional suffering, consequently ameliorating physical health and the quality of life. In addition, affordable and fast accessibility to mental health services would lower overall healthcare costs by reducing the number of medical visits and treatments. Hence, investing in psychologists and their care services would be the key in response to the growing need for mental health support in the aging population.

What is psychological aging?

“What age do you feel?” “Do you feel psychologically and physically younger, the same or older than your chronological age?” “If you could choose your age, what age would you like to be?”

Subjective psychological constructs and approaches gained momentum in investigating psychological health based on different subjective psychological concepts (e.g., subjective age, age identity, the aging self and attitude toward aging, self-perceptions of aging, and satisfaction) [2,3,4,5,6,7,8]. Other approaches have also investigated the self-perception of age in which the “perceived age” was associated with the subjective estimation. Particularly, this factor was found to influence how individuals cope with illnesses and symptoms (e.g., a positive view and attitude toward life are related to positive health outcomes) [9], likewise perceiving oneself younger than the actual chronological age would positively affect the age-related biological change, even though it was shown that the subjective age might also be influenced by socio-cultural values [1].

A recent review published in Aging [1] proposed non-modifiable and modifiable factors that might affect subjective age and its change across the lifespan, and thus potentially useful when developing individual psychological aging clocks to measure with high sensitivity health conditions and life satisfaction of patients and the general population. Moreover, several studies found a relationship between age identity and health, mental states, cognitive functioning, longevity, and wellbeing, and how subjective age was highly determined by health changes, life experiences, social interactions and relationships, and cultural values. Hence, based on this evidence the goal of public health initiatives and clinical interventions should be to promote a positive and sustainable attitude toward age and health [1].

But which are the biomarkers related to subjective age? Even though different studies investigated which factors contribute to determining subjective age, only a few focused on specific biomarkers. Among these perceived subjective ages, epigenetic factors and the biological system would require more investigation. Besides, examining changes associated with aging and the risk of developing mental health problems should be better addressed and how this association relates to productive functioning. Indeed, lower subjective age was found related to higher mental and physical health, life satisfaction, and cognitive capabilities. Here again, the importance of focusing on the identification of modifiable factors correlating with psychological age to improve life quality. Lately, the review suggested the importance of developing new tools to evaluate biopsychological profiles to enhance resilience against stress while evolving a positive attitude and proactive behaviors. Moreover, besides advances in artificial intelligence underneath the development of biological clocks, also the development of deep learning-based psychological aging clocks would value the importance of health toward the promotion of health longevity and target clinical interventions [1].

Geropsychology and the need to address mental health in aging

Previously, I have discussed how psychological support plays a relevant role in promoting mental health in aging, consequently influencing physical health, life satisfaction, and wellbeing. Therefore, the role of psychologists, independently or in a team of health professionals, is indeed to provide a variety of long-term care services to older adults across different care facilities (e.g., hospitals, homes, communities, assisted-living structures) while delivering and guaranteeing an interdisciplinary care practice.

Geropsychology is a branch of psychology focused on studying aging to provide proper clinical services. But who are geropsychologists? They investigate the aging process and test specific psychological interventions in response to common issues that affect and challenge the aging population. Whereas practitioners support caregivers and patients to overcome obstacles.

The growing need for psychological support is mostly related to the growing aging population, particularly care services directed to rural, poorer, ethnic, and racial groups. Integrating physical and mental health care interventions has a greater effect due to their interdependence, and for instance, elders suffering from heart diseases also have comorbidity with depression. Thus, targeting anxiety, depression, and stress would impact the ability to function and manage daily living activities with optimal physical conditions. Despite the difficulty in recognizing and treating mental health disturbances and due to the comorbidity of other chronic diseases in older adults, (gero)psychologists have a wide set of skills to diagnose and establish primary care interventions. Among psychological interventions, (gero)psychologists implement cognitive-behavioral, interpersonal, psychodynamic therapies, behavioral and disease management strategies, and cognitive training interventions. In addition, psychotherapies can be conducted independently of or in combination with psychiatric interventions, in combination or not with medications. Furthermore, throughout the variety of treatments, the focus of (gero)psychologists is to treat and recover from several mental health conditions such as the identification and improvement of stressors affective late life, anxiety, and depression disorders, caregiving capacities, dementia, end-of-life assistance and care, sleeping disorders, incontinence, chronic disease management, abuse and dependence on substances, suicidal risk and behavior to provide long-term care in late life.

APA Division 12-II (Clinical Geropsychology)

The APA Division 12-II (Clinical Geropsychology) is a part of the American Psychological Association (APA) that provides psychological services for elders through research and training activities. Therefore, the focus is on promoting mental and behavioral health that is often underestimated across the aging process and often left untreated. Accordingly, attention to affordability and lowering the costs of services are major points that the association aims to address to democratize the accessibility of care services among older adults and especially those groups with difficult living conditions (e.g., minorities). Lastly, a comprehensive care approach is fostered, in which a team made of (gero)psychologists and other healthcare professionals deliver assessments, interventions, and programs to target mental and physical (e.g., chronic diseases) health, besides offering support for caregivers and relatives.

Can we control psychological aging and improve our health?

Aging is a complex process happening at multiple levels, from biological to mental changes and thus influencing our hopes and expectations concerning life. And because this process starts already from our birth, it’s a feature that humans and other organisms have in common. Despite the rapid development of translational medicine, particularly focused on aging biomarkers, it remains difficult to slow or even reverse biological aging. Nevertheless, targeting and controlling psychological aging might be possible. Indeed, even though individuals age at different rates, specific biomarkers can be detected that precisely indicate age-related changes. Accordingly, “biological clocks” based on deep and machine learning techniques were proposed to measure biological aging and potentially be translated into clinical research to develop personalized treatments to address a diversity of age-related conditions.

In addition to biological markers of aging, also changes happening at the psychological level should be addressed. For instance, the consideration of specific life events that had an impact on our life, goals, expectations, beliefs, core values, and behavior toward others. Previously, an individual’s psychological age (e.g., how an individual perceives him/herself as younger/older/same age than their chronological age), known as subjective age or age identity, was found to affect physical health (e.g., decreased obesity and inflammation, increased liver enzymes and grip strength, body mass index) and brain health (e.g., grey matter volume, cognitive functioning). So what can be done to improve health and life decisions?

A recent article from Dr. Alex Zhavoronkov, an expert in AI for healthcare and longevity biotechnology, discussed how psychological aging, detectable through biomarkers, can potentially affect biological aging. He reported a research study that demonstrated how older subjective age is related to accelerated epigenetic aging, advancing the hypothesis of a close relationship between these factors and how subjective aging is also associated with life satisfaction, where a discrepancy between chronological and subjective age might have a negative effect. Moreover, other factors were found to affect long-term health and aging such as neuroticism (i.e., how the person experiences the world as threatening and unsafe) and conscientiousness (i.e., the tendency of an individual to be responsible and organized); two relevant personality traits belonging to the Big Five personality traits model. Attitude towards aging (e.g., self-perception of age, cultural and social stereotypes about aging) can affect, positively or negatively, health outcomes. Hence, a longitudinal study published in the Journal of Psychology and Aging investigated the role of these key personality traits in a sample of German adults across twenty years finding that low neuroticism and a positive attitude toward aging were highly related to stronger physical health, although having a high conscientiousness and positive attitude determined even higher effects on health. In the same journal, another interesting meta-analysis showed that subjective aging varies across different populations worldwide and how individuals aged 40 or even older reported feeling 6.4-21.1 years younger than their real chronological age. In addition, by comparing regions across the world, North America shows the highest discrepancy between chronological and subjective aging, followed by Western Europe and Oceania, and where the smallest discrepancy was observed in Africa, probably due to socio-economical and cultural factors.

In his article, Dr. Alex Zhavoronkov continues the discussion about the future time perspective. Awareness of time and the time an individual has “left” to reach goals is strongly associated with subjective age, due to a tendency of using the time already spent as an estimator of successes or failures. This fact matches the social-emotional selectivity theory that Dr. Laura Carstensen of Stanford University suggested. Hence, according to this theory, individuals tend to set goals based on the perception of time that is left and their future life perspectives. So, youngsters show a tendency for achieving knowledge-based goals, whereas seniors tend to shift their focus on closer relationships, life satisfaction, well-being, and higher management of negative emotions.

Having seen how perceived age has a great influence on promoting health and coping with physical diseases, closer attention should be paid to how stressful life events negatively affect health outcomes and biological aging, as shown by a study of military veterans in 2009, in which post-traumatic stress disorder was found to increase subjective agee and physical health problems, memory complaints, and weight gain. Besides, subjective age was also related to specific aging biomarkers (e.g., shorter leukocyte telomere length), thus negatively affecting aging even more than chronological age by itself. Similar findings were found linking depression to increased serum cortisol levels, cognitive decline, somatic and behavioral impairments, and where older subjective age was a predictor of depression development later in life in seniors.

The article continues by discussing how psychological aging can be measured. Previously presented, research studies tried to link psychological age and subjective age with health outcomes by relying on basic questions (e.g., “What age do you feel?” “Do you feel psychologically and physically younger, the same or older than your chronological age?”), although more recent approaches have also proposed implementing machine learning and neural networks to gather a deeper insight concerning subjective aging and health. Hence, in a newer research study, scientists at Deep Longevity implemented machine learning to explore data acquired from an extensive U.S. longitudinal study about health and well-being. Therefore, the research study investigated various factors (e.g., health conditions, quality of relationships, occupational concerns, community engagement, personality traits, beliefs, demographic features, life satisfaction, and well-being) related to chronological and subjective age based on neural networks. Results brought to the establishment of two psychological clocks, strong predictors of chronological, subjective age, and all-cause mortality risk; “PsychoAge” (i.e., a predictor of chronological age about health) and “SubjAge” (i.e., a predictor of perceived age), respectively. Surprisingly, the study demonstrated that both clocks could be “reversed” through behavioral and social interventions while highlighting the possibility of promoting healthier behaviors and a positive attitude toward life.

In conclusion, Dr. Alex Zhavoronkov speculates about future perspectives regarding research in psychological aging. Having already shown how biomarkers of aging might be translated into personalized interventions to extend lifespan and health, similarly could be predicted regarding subjective and psychological aging, in which the focus would be on lifestyle habits, life events, stress management, life quality, and satisfaction, and where artificial intelligence might be a promising technique to investigate these processes for the establishment of future interventions targeting health.

"Nature gives you the face you have at twenty; it is up to you to merit the face you have at fifty." (Coco Chanel)

References:

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