Man Ray’s Printmaking Techniques

There is no definitive age from which older age begins. Research currently uses varied definitions and can refer to older adults as people aged from 55 years (65), 60 years (66), and 65 years and beyond (67). The term older adults can be

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perceived as a negative descriptor, therefore in this thesis, the term mid to late adulthood will be used to define people who are at or over the age of 55 years;

the peri-retirement life-stage.

There is no consensus in the literature on the terminology or definitions used for the concept of healthy ageing. The term successful ageing has been used

predominantly, although this is changing. Various terms such as optimal-, productive-, positive-, active-ageing, ageing well and healthy ageing have been

used (68-72). The latter descriptors suggest the inclusion of QoL measures. More recently, the terms healthy living and active living have been used which

incorporate the principles of healthy ageing (73-75). This thesis uses the term healthy ageing to include all of these definitions.

The component parts of the healthy ageing framework are multidimensional and can include personal, social and environmental influences, lifestyle and

behavioural factors, as well as genetic and biological considerations. As such not all studies measure the same components; both objective and subjective

measures may be used. Some researchers include SEP and income measures (76-78), while others include freedom from major diseases (79, 80), self-rated health (68, 81), absence of cognitive impairment (82), longevity (80), or wellbeing and life satisfaction factors (82-84). To further add to the difficulty for meaningful comparison, previous research into healthy ageing has covered a wide range of ages at baseline. These may begin from age 58+ (85), 60+ (78, 81, 86) , 65+ (79, 80, 82, 84, 87, 88), 68+ (78, 89), 70+ (90, 91). Moreover, the investigation period of these studies varied between two years and over the life-course (72, 92).

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In their historic Science article on ageing, Rowe and Kahn (93) made the distinction between usual and successful ageing, where usual related to the

‘norm’ according to prevailing patterns of ageing in a given society, and

successful explained those people with minimal or no decrements in functional

loss compared with younger people. In subsequent investigations, the

researchers (94) determined three measures for successful ageing: absence of disease and associated risk factors, high functional capability (includes physical and cognitive factors), and active engagement with life. Since Rowe and Kahn’s landmark paper, research on successful ageing has adapted the framework (82, 83, 86, 95).

Collectively, the lack of standardized definitions of the healthy ageing framework may have resulted in imprecise definitions of healthy and/or unhealthy ‘agers’

(96). More recently, subjective definitions from the individual’s perspective have placed great importance on life satisfaction and wellbeing, otherwise known as QoL, as well as social involvement (95, 97, 98). Strawbridge et al. (83) evaluated a comparison of Rowe and Kahn’s measures of successful ageing (absence of disease, maintenance of physical and cognitive function, active engagement with life), with one based on self-rated criteria. The self-rated model showed 50% of respondents considered themselves to be ageing ‘successfully’, whereas the application of the Rowe and Kahn model reduced this figure to 18%. This figure would likely be further reduced if more common NCDs were added to the

‘diseases-related disability’ category.

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Quality of life

The term ‘quality of life’ is a dynamic construct dependent on time, place, and culture, and at which point in an individual’s life-course it affects (99). As such, QoL is now recognised as an integral component of health and wellbeing that covers both physical and mental health, and social cohesion. Self-rated health has been shown to be a useful indicator of QoL; indeed previous research observes individuals who rated their health as fair or poor to have the lowest QoL (100). Since the development of the World Health Organization QoL instrument (101), considerable research has been carried out on QoL. Much of the literature that focuses on QoL does so in the context of NCDs (102),

degenerative conditions such as Alzheimer’s disease (103, 104), depressive illness (105), and injury (106).

Numerous QoL measurement tools exist; some are brief (SF-8, SF-12) whilst others are longer and more comprehensive (SF-36, WHOQOL, EuroQoL) (101, 107). There is no universal ‘all purpose’ QoL measurement instrument, and each have their merit. However, the SF-36 is the most widely used.

The MOS 36-Item Short Form Health Survey (otherwise known as the SF-36) was originally developed for the Medical Outcomes Study (107, 108) to be

administered by phone, person-to-person interview, or as a self-administered survey. It is a reliable tool to measure health-related QoL (108-111). As the most widely used QoL instrument, the value of the SF-36 is grounded in its descriptive richness that some suggest other QoL instruments may not have (112-114). The

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SF-36 is practical, short, and can be incorporated into longer, more complex surveys.

The SF-36 comprises 36 questions, covering physical and mental health. Eight scales are constructed from these questions; four scales concerning physical health and four scales concerning mental health. The physical scales are physical functioning, role limitations due to physical problems, bodily Pain and general health perception. The mental scales are vitality, social functioning, role limitations due to emotional problems, and emotional wellbeing. In addition, there are two aggregated measures: The physical component summary (PCS) score, and the mental component summary (MCS) score. The aggregated scores each comprise a proportion of all eight scales, since physical components affect mental wellbeing, and mental components affect physical wellbeing. Of the research that is carried out using the SF-36, the PCS and the MCS scores are most commonly used to explain QoL (7, 29, 115-118), although the individual domains are used in some research (116, 119, 120).

Although the aggregated scores have utility, they do not provide a detailed explanation of the factors relating to physical or mental health. Therefore, valuable information may be overlooked or the scores may be misinterpreted.

For example, since all eight domains contribute to each of the PCS and MCS scores, the researcher is not able to identify which of the individual domains feature most prominently in the results.

Despite the decrements in functional health that may be seen with increased age, people with a positive outlook on ageing have reported to experience higher

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states of wellbeing (100). In contrast, those who reported negative attitudes to ageing experienced a less favourable state of wellbeing (121). This highlights an important point in that longevity is not the only pressing issue; rather, healthy life-years and QoL is the health imperative in ageing well.

Determinants of healthy ageing

Since the framework of healthy ageing is multifactorial, so too are its

determinants. There are key components that stand out as common drivers of healthy ageing: engagement in physical activity such as walking (77, 122) non-smoking status (90), higher SEP and income (123), active engagement with life, particularly connection with friends and/or family (78), attaining higher-level education (82), life-long learning, and high quality diet, particularly the inclusion of nutrient-rich foods (89), and high cognitive functioning (70). Other factors contribute positively to healthy ageing, but have been shown to be less strong predictors. These included: life satisfaction, wellbeing and positive adaptation (78), and independent living (91).

In view of the lack of a standardized definition for healthy ageing or agreement on its terminology, it is difficult to definitively compare findings. Nevertheless, throughout the literature there are aspects of the determinants of healthy ageing that overlap (Appendix A). This may concern their physical and/or mental health, or social connectedness; all of which contribute to the health and

wellbeing experienced by the individual.

Social capital and participation are important factors in health and wellbeing outcomes (124, 125). Social ties, either between friends and family or within the

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community, have shown to have a beneficial effect on health outcomes (125, 126). McPherson and et al. (127) expressed concern over their findings that social connectedness of individuals is being degraded. In that review, the proportion of people who have someone to discuss important and personal matters has diminished substantially, and this may translate into poor health for some. Other research supports these findings: a review on social relationships and mortality risk (128) concluded that people who have stronger social ties had a 50% better chance of survival that people without such relationships. Similarly, a European study on health, ageing and retirement (129) observed that all things being equal, those who entered into their fifties in good health had a greater tendency to engage in social activities with subsequent health benefits, than people who lived with poor health. The lack of social engagement therefore may accelerate a decline in health.

Between 1991 and 2006 the proportion of single person households in Australia rose from 7% to 10%, with more women than men living alone. Those people who were aged between 55 to 59 years in lone person households rose from 11% in 1991 to 14% in 2006. This figure is estimated to rise to 15% to 19% by 2031. Women of all age groups living alone are expected to increase from one million (in 2006) to around 1.7 million (in 2031) and men in single person households are projected to rise from 850,500 (in 2006) to around 1.3 million (in 2031) (130).

Marital disruption in mid to late adulthood raises important public health issues (131). Studies have observed women at this life-stage who divorce experience

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greater levels of illness, stress, and depressive symptoms ten years on, compared to those who are married (132). Similarly, a study investigating men and women from the British Household Panel Survey identified the loss of a partner, whether through separation or death, increased the odds of having no weekly contact with friends (133). It is not known if people who have previously cohabited, without marriage, are at equal risk. However since the issue here is the removal from the main source of support, it may be hypothesized that both marriage and cohabitation yield similar experiences.

People aged 65 years and over who are living alone have an increased risk of economic hardship (42). A population social trends appraisal has found that 20%

of people in this category were regarded as having low economic resources (134). As a major determinant of health, SEP is used in innumerable research:

longitudinal studies have consistently shown SEP predicts QoL and healthy ageing (82, 96, 123). Lower SEP, particularly low educational level and lower employment grade are strong indicators for functional limitations and unfavourable physical and mental health in later life.

As can be seen above, there are numerous influences on age and how well the human body ages. Although chronological age is important, age can also be measured as biological age; defined as how old the body seems (135). Aside from genetic factors, environmental factors such as diet, alcohol consumption,

smoking status and physical activity contribute to biological age (136, 137).

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