Longitudinal Studies

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The Harvard Study of Adult Development. This prospective longitudinal study elucidates the controllable factors that led to “aging well”. 

The Harvard/Grant Study: “Aging Well”

The Harvard/Grant study is made up of three cohorts: 268 Harvard males, 500 inner city males, and 90 “gifted” high-IQ women. These groups were studied for over 50 years and the controllable factors involved in aging well were identified. Aging well was determined through data derived from physical and psychosocial health measured both subjectively and objectively. 

Six domains were measured:

1. Objective physical disability - Physical exam every 5 yrs performed by study internist. (4 point scale - points 1-3 are not “disabling”. To have a “4” the study internist thought health was disabling and irreversible) .
2. Subjective physical health - Based on iadl’s (15 point scale), what a member thought could be accomplished independently.
3. Length of objective or subjective “undisabled” life.
4. Objective Mental Health - 4 domains (work, love, play, interventions). One does not need to score well in all 4 domains.
5. Objective Social Supports (ie family, social, religious)
6. Subjective Life Satisfaction - 8 domains (min 2 needed “very satisfying”): “Over the last 20 years, how do you rate marriage, children, work, friendships, hobbies, community service, religion, recreation?”.

The Harvard study found that that those who were aging well (regarding the above six domains) had the majority of the following characteristics:

• Successfully progressed through Erikson’s stages of social maturation. Social maturation - “Successful navigation of developmental “tasks” (stages) means one has: become my own identity, shared reciprocal intimacy, engaged in fulfilling work, passed on knowledge to the next generation (caregiver), kept meaning (caretaker), and have done so with integrity (an understanding or meaning of my existence).
• Used mature, rather than immature, Freudian defense mechanisms in the domain of emotional maturation. “Mature defense mechanisms” are used in various life domains and allow one to adapt to difficult thoughts, emotions, and circumstances. 
• An absence of alcohol abuse. 
• Healthy weight/BMI (obesity vs not obese).
• Longtime marriage, or intimacy, or meaningful friendships (10 plus years).
• Engaged in exercise (min 2 days per week).
• Engaged in education as an adult. This factor alone was a strong predictor of successful aging and included any four year degree from any university.
• Either was not a smoker or stopped smoking before 50.

The MacArthur Foundation Study of Successful Aging. The MacArthur Study focussed on the factors that promote maximizing the physical and mental functioning of aging adults. The cohort (n = 1,192) consisted of persons aged 70-79, and utilized high functioning participants, functioning in the top third of a six point screening process (physical and cognitive), residing in three US cities. 

The MacArthur Study of Successful Aging

1,189 high functioning adults ages 70-79 were studied for 11 years. Eligibility to participate was determined through a six point screening process (physical and cognitive). The highest functioning third were asked to participate in the study.  Successful aging was defined by three outcome domains. The study also identifies controllable factors within those three outcome domains. The domains are:

1. Low risk of disease and disease-related disability, 
2. High cognitive and physical functioning, and 
3. Active engagement with life.   

Each of those three outcome domains consist of sub-domains and many of those sub-domains are controllable. 

The domain low risk of disease does refer to absence of disease, but also refers to addressing/avoiding the various risk factors for disease along with addressing the severity of any of those risk factors. For example, coronary heart disease and cancer (the number one and number two causes of death) have risk factors associated with these diseases. Many of those risk factors are controllable. Addressing those controllable risk factors are a crucial component of MacArthur’s model of successful aging. 

The domain of high cognitive and physical functioning also contains subdomains. One sub-domain regarding high levels of cognitive and physical functioning focuses on moving beyond the functional potential for an activity. It involves actively engaging consistently in cognitive and physical activities. For example, high levels of physical functioning would mean that one doesn’t only have the potential to walk a mile, it means that one is actually walking a mile as a practice. Furthermore, as with disease risk, another sub-domain of high cognitive and physical functioning involves addressing any risk regarding one’s present and future cognitive and physical functioning levels. For example, some cognitive risk factors include drinking alcohol daily, poor sleep, social withdrawal, etc. In the cognitive domain, successful cognitive aging would involve adopting a lifestyle that minimizes those controllable risk factors and maximizes active cognitive engagement.

The third domain, active engagement with life, can take many forms, but the MacArthur Study found two domains of activity to be preferable regarding successful aging. Those two sub-domains are meaningful socialization and engagement in productive activities. Meaningful socialization/social engagement includes active exchange of information, emotional support, and giving and receiving various types of assistance to others, etc.  Productive activities are activities that have a societal value (even if the activity is unpaid) such as volunteer work, teaching, etc.  One important note regarding engagement with life is that sustained or consistent engagement in those activities is crucial.

The Adventist Health Studies. Adventist Health Study 1 (AHS 1), Adventist Health Study 2 (AHS 2), and The Biopsychosocial Religion and Health Study (BRHS, substudy of AHS 2, also known as: Adventist Religion & Health Study). AHS 1 studied  63,530 California Adventists to explore the protective lifestyle factors regarding cancer and heart disease. AHS 2 studied 96,000 North American Adventists exploring the relationship of lifestyle, diet and disease. BRHS utilized 10,988 participants from AHS 2 to explore “the psychosocial manifestations of religion”.

Adventist Health Studies

The Adventist Health Studies explore links between disease, diet, and lifestyle. The Adventist Health Studies explored here consist of:  Adventist Health Study 1 (AHS 1), Adventist Health Study 2 (AHS 2), and the Biopsychosocial Religion and Health Study (BRHS), also known as: Adventist Religion & Health Study (A subset of AHS 2). 

Adventist Health Study 1. The Adventist Health Study 1 (AHS 1) studied  63,530 California Adventists to explore the protective lifestyle factors regarding cancer and heart disease. The study found:

• Diet/lifestyle were linked to cancer and heart disease.
• Diet/lifestyle protective factors included: a vegetarian diet, exercise, body weight, and abstinence of smoking and alcohol. 
• When all  factors were present, Adventists lived approx 10 yrs longer than those with none of those factors.

Adventist Health Study 2. The Adventist Health Study 2 (AHS 2) studied 96,000 North American Adventists exploring the relationship of lifestyle, diet and disease. Findings included:

• Lifestyle factors promoting longevity, and aligned with Adventist values, included vegetarianism, exercise, and restraint from alcohol, tobacco.
• Cancer, cholesterol, diabetes, high blood pressure trended towards vegetarians have lower disease risk.
• The closer one is to being a complete vegetarian, the lower the disease risk.

Adventist Religion and Health Study/Biopsychosocial Religion and Health Study (ARHS/BRHS). This study utilized 10,988 participants to explore “the psychosocial manifestations of religion”. Findings include:

• Adventists reported better mental health than non-Adventists 
• Adventist mental health advantage is greater for older adults (age 60+) and that advantage increases with age. 
• SDA lifestyle of: supports, socialization, service, and sabbath keeping increased psychosocial well being. 
• Positive religious coping contributes significantly to psychosocial well being. 

The ARHS/BRHS found 10 factors that contributed to Adventists psychosocial health. Four of those are religious factors, and six are mediating variables.

  The four religious variables include:

1. Affective: belief in a loving (vs. controlling) God, gratitude, forgiveness, eschatological attitude.
2. Cognitive: positive religious coping, spiritual meaning.
3. Behavioral: prayer, sabbath keeping, church attendance, organizational activities.
4. Social engagement in the religious domain: participating in a sense of community, active engagement with religious supports.

The six mediating variables are:

1. Healthy behaviors and personal lifestyle variables.
2. Social integration and social support.
3. Personal efficacy, self-esteem, including the belief that, “I am capable”.
4. Positive (vs. negative) emotions (through methodologies such as reframing).
5. Healthy beliefs including optimism (vs. pessimism).
6. Coping resources and behaviors.

Longitudinal studies identify many factors involved in aging well that are within one’s locus of control. Psychosocial functioning, behavioral health, maintaining a healthy lifestyle are factors leading to increased well being and do contain numerous aspects that are controllable. Gleaning from those three longitudinal studies the following factors stand out:

• Importance of socialization, social support, and relationships.
• Active and consistent engagement in activities that have meaning/purpose.
• Mindset regarding self-efficacy.
• Methodologies of navigating life stages and conflict (Freud, Erikson).
• Coping strategies, or problem solving strategies, that are solution focused.
• Maintaining one’s cognitive health through active engagement in various cognitive domains (education is one method that tends to bring significant benefit).
• Maintaining physical health (lifestyle, diet, exercise, etc.) which assists mental health.