ABSTRACT
BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) often present with severe acute exacerbations requiring hospital treatment. However, little is known about the prognostic consequences of these exacerbations. A study was undertaken to investigate whether severe acute exacerbations of COPD exert a direct effect on mortality. METHODS: Multivariate techniques were used to analyse the prognostic influence of acute exacerbations of COPD treated in hospital (visits to the emergency service and admissions), patient age, smoking, body mass index, co-morbidity, long term oxygen therapy, forced spirometric parameters, and arterial blood gas tensions in a prospective cohort of 304 men with COPD followed up for 5 years. The mean (SD) age of the patients was 71 (9) years and forced expiratory volume in 1 second was 46 (17)%. RESULTS: Only older age (hazard ratio (HR) 5.28, 95% CI 1.75 to 15.93), arterial carbon dioxide tension (HR 1.07, 95% CI 1.02 to 1.12), and acute exacerbations of COPD were found to be independent indicators of a poor prognosis. The patients with the greatest mortality risk were those with three or more acute COPD exacerbations (HR 4.13, 95% CI 1.80 to 9.41). CONCLUSIONS: This study shows for the first time that severe acute exacerbations of COPD have an independent negative impact on patient prognosis. Mortality increases with the frequency of severe exacerbations, particularly if these require admission to hospital.
Subject(s)
Pulmonary Disease, Chronic Obstructive/mortality , Acute Disease , Adult , Aged , Epidemiologic Methods , Forced Expiratory Volume/physiology , Humans , Male , Middle Aged , Prognosis , Pulmonary Disease, Chronic Obstructive/physiopathology , Vital Capacity/physiologyABSTRACT
A study is made of the ultrastructure and variations in pinealocyte caryometric indices in 45 male albino rats (240 +/- 40 gm). Fifteen animals were subjected to exposed pineal body irradiation for 6 continuous minutes with soft He-Ne laser light. The irradiated rats were sacrificed in groups of five 3, 6 and 15 days post-irradiation. The control and sham-operated (craniotomy without irradiation) groups consisted of the same number of animals as the experimental groups. The results show a significant decrease in indices (p less than 0.0005) in all experimental groups in relation to the control and sham-operated animals, although in terms of the latter p for the three days post-irradiation group was 0.002. A progressive and significant decrease (p less than 0.002) was also observed between the experimental groups after 3 and 15 days and after 6 and 15 days, but not between the experimental groups after 3 and 6 days. Ultrastructurally, there were signs of secretory activity increase in the groups after 3 and 6 days, and decrease in such activity after 15 days--along with the appearance of cells of mesoglial lineage. A significant increase was observed in the number of peri-canalicular dark cells. The results are discussed and compared with those of other authors and different light energies.
