RESUMO
Stressful conditions lead to formation of excessive reactive oxygen species (ROS) and cause oxidative stress and aging. The aim of this study was to determine superoxide dismutase (SOD) and catalase (CAT) activity, and malondialdehyde (MDA) levels in nurses of a hospital intensive care unit according to demographic and occupational parameters, and to analyse the relationship with aging. Thirty-two nurses working in an intensive care unit and 35 aged-matched healthy individuals of both sexes as a control group were surveyed. No significant variations with respect to sex were detected in SOD, CAT, MDA and burnout levels. MDA levels increased with age in both the control group and the nurses, and we observed significant differences in MDA levels between the control group and nurses for all age groups. Significant variations in MDA levels were detected between single (286.12 +/- 8.41) and married (318.82 +/- 6.02), people, between those who frequently practice some kind of sport (281.41 +/- 7.32) and those who never participate in sport (298.24 +/- 8.11) ,and between those who frequently eat fruit and greens (289.75 +/- 8.41) and those who never eat them (315.12 +/- 7.21). Significant differences were detected between smokers and nonsmokers in SOD, CAT and MDA, but not for alcohol, coffee, tea or cola consumption. Higher SOD activity and MDA levels were detected in nurses on evening and night shifts (P < 0.01); these nurses also scored significantly higher on burnout subscales. These results suggest that: (1) occupational stress increases oxidative stress levels as a response to elevated ROS generation; (2) occupational stress increases MDA levels as a response to an elevation in free radical generation and can lead to aging; (3) working evening and night shifts increases oxidative and burnout levels. It is evident that preventive changes in job conditions and lifestyle are necessary to improve the quality of life of nurses who work in intensive care units.
RESUMO
BACKGROUND & OBJECTIVE: There is evidence that reactive oxygen species (ROS) plays an important role in the pathophysiology of many paediatric disorders. We carried out this study to see whether superoxide dismutase (SOD) activity was associated with age, sex and rural or urban status in three groups of Spanish people (newborns, children and young). METHODS: SOD activity was measured in red blood cells in newborns, children and young Spanish people (n=1212, divided in six groups) using the Minami and Yoshikawa method. RESULTS: The newborns had high levels of SOD activity, but among all age groups studied, SOD showed the highest activity in groups 1 and 2. We also observed that this activity decreased gradually with age until achieving adult levels. No significant variations with respect to sex were detected, except for the >or=14 to 18 yr age group, in which SOD activity decreased significantly in females. INTERPRETATION & CONCLUSION: Our findings show that SOD activity in newborns, children and young Spanish people is affected by age but not by gender (except from >or=14-18 yr) or rural or urban status.
