In the decades to come, Sweden will be facing an unprecedented increase in the proportion of inhabitants aged 80 years or older. This age group is characterised by large heterogeneity; however ageing also poses challenges for health and well-being. These challenges apply not only to the individual, but also to the health care systems. Care of this older age group employs much of the nursing resources, affecting society as a whole. Healthy ageing can and should, therefore, be promoted in the decades prior to reaching old age, and once having reached old age, well-being should be a continued focus of health care and society. In this way older adults can continue perceiving good health and well-being. The overall aim of this thesis was to explore and describe areas of importance to healthy ageing and well-being in old age. 

Predictors of healthy ageing were prospectively studied as part of the northern Sweden Silver-MONICA project, from baseline in 1999 (n=1595) to follow-up 20 years later (n=541). For the healthy ageing outcome, a composite outcome comprised of measures of cognition (MMSE), 2.4 metre walking speed, personal independence in everyday life (Katz P-ADL) and depression (GDS15) was constructed. To study perceptions of general well-being in old age, a subsample (n=52) age > 80 was analysed as a cross-section using mixed method with open-ended interviews and the PGCMS well-being measure. A similar approach was used (n=50) to investigate specific aspects of well-being in relation to home. To study the relationship between well-being and objectively measure everyday physical activity, an accelerometer was worn 24 hours per day for at least 5 consecutive days (n=77) and analysed for associations with the PGCMS and its subscales.  

The five top ranking predictors determined by the healthy ageing index, comprising the total baseline cohort including those who passed away before possible follow-up were smoking status, NT-proBNP, waist circumference, leisure time physical activity level and HbA1c. For those who participated in the Silver-MONICA follow-up, the top five ranking predictors as determined by the healthy ageing index were leisure time physical activity, HbA1c, BMI, waist circumference and high sensitivity Troponin I. In interviews of general well-being, six areas were described that related to social context, health, physical activity, home, engagement and freedom. In regression analysis independence in activities of everyday living along with age were significantly associated with well-being. Acceptance was key for handling consequences of ageing that impacted well-being. Home was perceived as a central aspect of well-being; however, participants described being in the margins of home. Morale was higher among persons living in single-dwelling housing compared to those living in apartments. In activity measures, well-being was associated with the number of steps, time spent stepping and time spent stepping at >75 steps/minute.

In conclusion, the combination of qualitative, quantitative and mixed methodology utilised in this thesis to study healthy ageing allowed for the possibility to nuance conclusions and to describe the subject from different points of view. Based on the findings, this thesis suggests that physical ability in old age is the basis for being able to engage in and experience the important factors of well-being described above. However, support from others, often family, can compensate for the lack of physical ability. The support is positive to well-being as long as it does not create feelings of being a burden. As consequences of ageing affect the areas most crucial to well-being, it seems that the extent and way these changed conditions are accepted has an important role in the maintaining of well-being in old age.