Nutrition, exercise and body composition in community-dwelling older adults : Effects on function, wellbeing and mortality

Sammanfattning: Background: The demographic shift in society with more people reaching a high age provides new challenges for both society and the healthcare system.Aim: The overall aim of this thesis was to examine the impact of nutrition, exercise and body composition on function, wellbeing and mortality in community-dwelling older adults.The thesis is based on 1) data from the Vitality, Independence and Vigor in the Elderly 2 study (VIVE2) (Papers I-III), i.e. 149 community-dwelling participants >70 years who took part in an exercise program, and were randomized to take either a protein- and vitamin D-rich supplement or a placebo for 6 months and 2) three cohorts from two Swedish population studies on older adults (Paper IV). Quantitative (Papers I, II and IV) and qualitative methods (Paper III) were used. Results: Paper I reports cross-sectional data showing that there was no clear association between serum levels of serum 25(OH)D and physical performance in mobility-limited adults.In Paper II, the results of the VIVE2 study indicated positive effects on mental health from exercise but no additional effect from supplementation was detected.In Paper III, the qualitative interview investigation indicated that the VIVE2 intervention had positive effects, both psychologically and physically. Another finding was that weight loss was a main reason for participants wanting to take part in the study, whereas the aim of the study was to improve muscle function.Paper IV shows from prospective observational data that 75-year-old women with sarcopenic obesity had an increased mortality risk within 10 years, while a similar result could not be found among 75-year-old or 88-year-old men.Conclusion: The exercise intervention improved the mental status of the participants based on both quantitative and qualitative studies. No effect could be attributed to the protein- and vitamin D-rich nutritional supplement, a finding that needs to be evaluated in light of the participants’ good nutritional status. No clear association was revealed between physical function and serum 25(OH)D. Sarcopenic obesity may be associated with mortality but such associations may depend on age and gender.