Evaluation of dose-response relationship between smoking load and cardiopulmonary fitness in adult smokers: A cross-sectional study.

OBJECTIVE: To evaluate the dose-response relationship between smoking load and cardiopulmonary fitness, as measured with cardiopulmonary exercise testing (CPET), in adult smokers free of respiratory diseases. METHODS: After a complete clinical evaluation and spirometry, 95 adult smokers (35 men and 60 women) underwent CPET on a treadmill. RESULTS: The physiological responses during CPET showed lower cardiorespiratory fitness levels, regardless of smoking load, with a peak [Formula: see text] lower than 100% of the expected value and a lower maximum heart rate. We observed a significant moderate negative correlation between smoking load and peak [Formula: see text] . The smoking load also presented a significant negative correlation with maximum heart rate(r=-0.36; p<0.05), lactate threshold(r=-0.45; p<0.05), and peak ventilation(r=-0.43; p<0.05). However, a dose-response relationship between smoking load quartiles and cardiopulmonary fitness was not found comparing quartiles of smoking loads after adjustment for age, sex and cardiovascular risk. CONCLUSION: There appears to be no dose-response relationship between SL and cardiopulmonary fitness in adult smokers with preserved pulmonary function, after adjusting the analysis for age and cardiovascular risk. Our results suggest that smoking cessation might be useful as the primary strategy to prevent cardiopulmonary fitness decline in smokers, regardless of smoking load. Thus, even a very low dose of tobacco use must be avoided in preventive strategies focusing on becoming people more physically active and fit.

Nosocomial occurrence of enterotoxigenic multiresistant Staphylococcus strains in Rio de Janeiro.

We studied 46 Staphylococcus aureus strains with three patterns of antimicrobial resistance (MARSA, MRSA and MSSA) obtained from inpatients of a large community hospital in Rio de Janeiro, Brazil. The strains showed a single biochemical pattern. On the contrary, remarkable phage-typing differences could be observed. Thirteen strains were associated to phagic group III and the remainder could not be typed even though most of them had shown a weak sensitivity to phage 54. Fourteen strains synthesized one or more enterotoxins. Enterotoxin D was synthesized more often. Neither was EEB produced nor TSSF-1. The results suggested the widespreading of different staphylococci strains in that hospital. There was strong evidence that some cases of nosocomial infections leading to death have been caused by the same S. aureus strain recovered from some inpatients in the intensive care unit.