Nutritional status and well being. Is there a relationship between body mass index and the well-being of older people?

Poor nutritional status may impair well being indirectly as a consequence of increased morbidity and decline in functional status. The aim of this study was to examine the independent effect of body mass index on the well being of older people. Thirty one hospital-based patients over 65 years of age were studied. Well being was assessed using the Philadelphia Geriatric Center Morale Scale (PGCMS)--anglicised version. Body mass index and well being were assessed on admission to hospital and at three months. At follow-up, a significant correlation was observed between body mass index and PGCMS values. Further analysis showed that this relationship was linear, with poor nutritional status being associated with low levels of well being and good nutritional status being associated with the highest levels of well being. High or low body mass index was able to predict the PGCMS score with a poor sensitivity of 44% and specificity of 96%. When the contribution of potential confounding variables was analysed, body mass was found to have no significant independent effect on well being. Instead, the presence of depression was the most powerful predictor of levels of well being. In conclusion, this study has demonstrated that nutritional status, as indicated by body mass index, has no detectable independent effect on well being. However, measurement of nutritional status may still have a role in the assessment of well being, in that, while the finding of a low body mass index cannot be taken as indicative of low levels of well being, the finding of a high body mass index is likely to indicate adequate well being. Further studies, however, are required in this area that would involve larger numbers of subjects and alternative measures of nutritional status and well being.

Ageing: definitions, mechanisms and the magnitude of the problem.

All multi-cellular organisms undergo change with time. Conception heralds the onset of growth and development, leading to reproductive competence and propagation of the species. With time, organisms age, leading to death as a final end-point. Whilst our knowledge and definitions of growth and reproduction are firmly established, the concept of ageing remains less well understood. One of the reasons for the lack of a singular definition of ageing is that it can be considered in many different ways, according to social, behavioural, physiological, morphological, cellular and molecular changes. Research has led to a number of theories being proposed that may explain the ageing process. In this chapter, we will review some of these theories and address some of the following fundamental questions: What is ageing? How can ageing be measured? When does ageing begin? When is an organism defined as old?