ABSTRACT
Aging and the diseases that typically follow with increasing age, notably atherosclerosis and cancer, are often proposed to be involved in increased oxidative stress. Animal studies, on the other hand, show no clear-cut pattern of age-related changes in enzymatic antioxidant defences. In this study we have demonstrated that total peroxyl radical scavenging antioxidant capacity (TRAP) in human plasma changes with age. We also found that among the antioxidants in human plasma there exists a major fraction of so far unidentified antioxidant(s). A chemiluminescent TRAP assay was used to determine the presence of peroxyl radical scavenging antioxidants in human plasma. The material consisted of 87 healthy volunteers, aged 20-96 years, who used no regular medication, vitamins, or trace elements. In females, total antioxidant capacity increased significantly during the life span. The increase in TRAP was mainly due to unidentified antioxidants. In males, TRAP increased until age 51-74, and then significantly decreased. The decrease observed among males was also due to the sharp decline in the concentration of unidentified antioxidants.
Subject(s)
Aging/blood , Free Radical Scavengers/blood , Peroxides/metabolism , Adolescent , Adult , Aged , Aged, 80 and over , Animals , Antioxidants/analysis , Ascorbic Acid/blood , Chromans/blood , Female , Free Radicals/metabolism , Glutathione/blood , Humans , Male , Middle Aged , Oxidative Stress , Sulfhydryl Compounds/blood , Uric Acid/blood , Vitamin E/bloodABSTRACT
The purpose of this study was to measure the rate of falls and to identify the causes, consequences and opportunities for preventing falls among 796 permanent residents of a nursing home. Altogether 377 falls were reported among 207 residents during the study period. The most important association discovered was that between impaired visual acuity and falls. In addition, 49% of the fallers suffered from severe and 19% from mild dementia. In the group of demented subjects it was impossible to assess visual acuity in 30% of the fallers as the subjects were unable to fixate at request. This finding may be one explanation for the increased incidence of falls in demented subjects. We conclude that the high number of subjects suffering from dementia among institutionalized elderly limits the possibility of training in prevention. The main emphasis in prevention of falls in institutions should be in proper design of the environment, including the visual environment.
