Cell-Mediated Immunity as a Predictor of Morbidity and Mortality in Subjects Over 60

Abstract

Previous studies have suggested an association between depressed cell-mediated immunity and increased mortality in elderly persons. However, the effects of age and existing disease on this association have not been adequately addressed. We studied the association between cell-mediated immunity and subsequent morbidity and mortality in 273 initially healthy persons 60 years of age and older. In 1979, two tests of cell-mediated immunity were conducted--mitogen stimulation with phytohaemagglutinin, and delayed hypersensitivity skin testing. The study group was followed annually for development of pneumonia, cancer, and death. Anergy was associated with all-cause mortality (hazard ratio of 2.16; 95% confidence interval [1.10,4.28]). When the results were adjusted for age, the resulting hazard ratio was 1.89;[0.94,3.79]. A relationship was also suggested between anergy and cancer mortality although this association was not statistically significant. Response to phytohaemagglutinin was a poorer predictor of mortality than was response to delayed hypersensitivity skin testing. The results show that anergy may be a good indicator of subsequent all-cause mortality, and perhaps cancer mortality, in elderly who lack other indicators of poor health.

Effects of antioxidants on immune system ageing

“…The senescent decrease in antioxidant levels supports the free radical theory of ageing, and provides a rationale for decreasing the rate of ageing by supplementing the diet with these antioxidants (Miquel & Weber, 1990). Previous studies from our laboratory, in old mice as well as in elderly men and women, have demonstrated the beneficial effects in vitro and in vivo, on the immune functions, of the antioxidants mentioned above (De la Fuente et al, 1998a,b;De la Fuente & Victor, 2000;Ferrández et al, 1999), and we should emphasize that an adequate immune system is a marker of health and longevity (Wayne et al, 1990). Moreover, the antioxidant doses should be higher in old animals than in the adult in order to improve the immune system (De la .…”

“…Thus, the immune system has been proposed as a marker of biological age and life span since a suboptimal immune function may significantly contribute to morbidity and mortality in the elderly. Moreover, an association between immune function and individual longevity has been suggested (Wayne et al, 1990).…”

The prevalence and risk factors for age-related macular degeneration in rural–urban India, Sankara Nethralaya Rural–Urban Age-related Macular degeneration study, Report No. 1

“…The illness patterns in the elderly reflect both a deterioration of immune function and increased incidence of upper respiratory infections, shingles, tuberculosis and cancer. Moreover, prospective studies indicate that older persons with low delayed-type hypersensitivity skin test (DTH) responses have higher morbidity, are less selfsufficient, and have a higher incidence of post-operative complications and mortality compared with those with normal DTH responses (90)(91)(92).…”

Murine models of premature ageing for the study of diet-induced immune changes: improvement of leucocyte functions in two strains of old prematurely ageing mice by dietary supplementation with sulphur-containing antioxidants

“…In the cells of innate immunity, the phagocytic cells show functions that decrease with ageing and others that are over activated (2,(11)(12)(13) , whereas the anti-tumoral activity of natural killer (NK) cells, in most of the work, shows an age-related decrease (2,11,14) . In addition, it has been demonstrated that the competence of the immune system is an excellent marker of health (2,4,8,15,16) and several age-related changes in immune functions, such as low T-cell proliferative responses, IL-2 secretion and NK cell cytotoxicity, have been linked to longevity (2,15,16) . In previous studies, the earlier-mentioned functions and other immune functions, in lymphocytes and phagocytes, have been established as markers of biological age and therefore as predictors of longevity (2,13,16,17) .…”