Now more than ever, an increasing number of people can look forward to reach old age. However, increasing age is associated with increasing morbidity.
Multiple illnesses are often associated with decreases in quality of life and life expectancy. There are, however, substantial differences between persons. PREFER examined whether the way individuals cope with their illnesses, think about their illnesses and act despite or because of their illnesses could explain such differences in quality of life and autonomy
Individual attitudes and thoughts, health behaviors and individual health affect each other reciprocally over time. For example, physical limitations might affect individual attitudes towards health. On the other hand, such changes in attitudes might affect individual behavior, which in turn impacts on behavior and health.
In order to examine such reciprocal relations, we designed PREFER as a longitudinal study with three measurement points over one year.
The main aim of the study was to identify factors that allow older people with multiple illnesses to maintain or improve their health behaviors and health status. The results of PREFER can inform effective interventions to support older people with multiple illnesses in their autonomy and quality of life.
Here are some basic results from PREFER:
- Self-efficacy and social support interact in promoting physical activity in older people with multiple illnesses: A moderate amount of both resources is needed to promote physical activity (Warner et al., 2011-b)
- Self-efficacy for physical activity is mostly based on previous mastery experiences and on model learning – verbal persuasion seems less important (Warner et al., 2011-a)
- Illness representations for multiple illnesses depend on both illness-specific information and on factors on the level of the person (e.g., self-efficacy) - this means that on top of illness-related information, personal characteristics affect the way we think about different illnesses (Schüz et al., 2012)
- Individual views on aging affect how people cope with serious health events: People who expect more losses in old age are less likely to adaptively engage in health-promoting activities (Wurm et al., 2013).
- Changes in functional health affect what people think about their medicines – Functional improvement leads to less perceptions of necessity, and changes in such perceptions affect individual adherence behavior (Schüz et al., 2011)
- Schüz, B., Wurm, S., Warner, L. M., & Ziegelmann, J. P. (2012). Self-efficacy and multiple illness representations in older adults: A multilevel approach. Psychology & Health, 21, 13-29. doi: 10.1080/08870446.2010.541908
- Schüz, B., Wurm, S., Ziegelmann, J. P., Warner, L.M., Tesch-Römer, C., & Schwarzer, R. (2011). Changes in functional health, changes in medication beliefs and medication adherence. Health Psychology, 30, 31-39.
- Warner, L.M., Schüz, B., Knittle, K., Ziegelmann, J. P., & Wurm, S. (2011-a). Sources of perceived self-efficacy as predictors of physical activity in older adults. Applied Psychology: Health and Well-Being, 3, 172–192.
- Warner, L.M., Ziegelmann, J. P., Schüz, B., Wurm, S., & Schwarzer, R. (2011-b). Synergistic effect of social support and self-efficacy on physical exercise in older adults. Journal of Aging and Physical Activity, 19, 249-261.
- Wurm, S., Warner, L. M., Ziegelmann, J. P., Wolff, J. K., & Schüz, B. (2013). How do negative self-perceptions of aging become a self-fulfilling prophecy? Psychology and Aging, 28, 1088-1097. doi: 10.1037/a0032845
Design and Sample
PREFER I was based on the German Ageing Survey (DEAS). All PREFER participants had previously participated in the German Ageing Survey and were considered eligible for the study based on inclusion criteria:
- Being 65 years or older
- Having at least two diseases from a list of diseases in DEAS
- Having declared explicit consent to participate in further studies based on DEAS
After DEAS data collection, individuals fulfilling the inclusion criteria were contacted in early 2009. The goal was to assess about 300 persons. In total, 309 participants were recruited for PREFER and were visited by trained interviewers in March 2009. Interviewers conducted a computer-assisted personal interview (CAPI), a full medication inventory and employed Peak Expiratory Flow measurements and a sit-to-stand test as indicators of physical health. In addition, participants were asked to fill in a questionnaire. In June 2009, a first postal follow-up was conducted, and in September 2009, and interviewers returned to participants in September 2009 for another personal interview and health assessments.