[Passive smoking in adults]

[ETAP: A smoking scale for Primary Health Care]

OBJECTIVE

To obtain a scale of tobacco exposure to address smoking cessation.

DESIGN

Follow-up of a cohort. Scale validation.

SETTING

Primary Care Research Unit. Tenerife.

PARTICIPANTS

A total of 6729 participants from the "CDC de Canarias" cohort.

METHODS

A scale was constructed under the assumption that the time of exposure to tobacco is the key factor to express accumulated risk. Discriminant validity was tested on prevalent cases of acute myocardial infarction (AMI; n=171), and its best cut-off for preventive screening was obtained. Its predictive validity was tested with incident cases of AMI (n=46), comparing the predictive power with markers (age, sex) and classic risk factors of AMI (hypertension, diabetes, dyslipidaemia), including the pack-years index (PYI).

RESULTS

The scale obtained was the sum of three times the years that they had smoked plus years exposed to smoking at home and at work. The frequency of AMI increased with the values of the scale, with the value 20 years of exposure being the most appropriate cut-off for preventive action, as it provided adequate predictive values for incident AMI. The scale surpassed PYI in predicting AMI, and competed with the known markers and risk factors.

CONCLUSION

The proposed scale allows a valid measurement of exposure to smoking and provides a useful and simple approach that can help promote a willingness to change, as well as prevention. It still needs to demonstrate its validity, taking as reference other problems associated with smoking.

Volatile organic compounds in exhaled breath in a healthy population: effect of tobacco smoking

INTRODUCTION

Tobacco smoke is a source of free radicals and reactive oxygen and nitrogen species, which are the main causes of oxidative stress. The analysis of volatile organic compounds (VOC) in exhaled breath is an indirect method of measuring the level of oxidative stress that occurs in the airways caused by tobacco consumption. The aim of this study was to determine whether smoking influences the production of VOC, in a clinically healthy population.

METHODS

Exhaled breath from 89 healthy volunteers, divided into three groups (non-smokers, ex-smokers and smokers) was analysed. Samples were collected using Bio-VOC® devices and transferred to universal desorption tubes. Chemical compounds were analysed by thermal desorption, gas chromatography and mass spectrometry. We analysed hexanal, heptanal, octanal, nonanal, nonanoic acid and propanoic acid, all identified by retention time and mass spectra referenced in the NIST 08 mass spectral library; confirmation was carried out using reference standards of the pure chemical compound.

RESULTS

These VOC were found in very low concentrations. Only nonanal showed significant quantitative and qualitative statistical differences among the study groups. Nonanal concentration is dependent on smoking, but is independent of the amount of tobacco consumed, age and gender.

CONCLUSIONS

Nonanal in exhaled breath is associated with tobacco consumption, current or previous. Nonanal is a sub-product of the destruction of the cell membrane, and its finding may be indicative of cell damage in smokers. This result appears in many farmers who smoke.

Impacto de la implantación de una política de trabajo libre de humo en una empresa

OBJECTIVE

To assess the impact of a smoke-free workplace policy in a company.

METHOD

The impact of the implementation of a smoke-free workplace policy was assessed between October 2001 and February 2003 in a company with 184 employees. Two surveys of the entire staff were performed, one before the implementation of the new policy and the other 14 months after.

RESULTS

Both passive exposure to tobacco smoke and tobacco consumption among smokers decreased. The proportion of workers free of tobacco smoke exposure at their workplace increased from 32% to 84% (p < 0.001) and, among smokers, the mean daily consumption of cigarettes was reduced by 7.3 cigarettes (p = 0.049).

CONCLUSIONS

Demarkation of areas where smoking is allowed not only reduces passive exposure to tobacco smoke at the workplace but also seems to encourage smokers to quit smoking or to reduce tobacco consumption.

[Influence of computed tomography of the abdomen for staging lung cancer]

OBJECTIVES

To analyze the influence of routine imaging of the upper abdomen by conventional computed tomography (CT) to stage bronchopulmonary carcinoma and to detect liver or adrenal metastasis. A second objective was to describe the characteristics of a large group of patients in our practice.

MATERIAL AND METHODS

Retrospective study of 387 patients (367 men and 20 women; mean age [+/-SD] 62.3 +/- 10.4 years, range 34-90 years) who had received a diagnosis of lung cancer (203 epidermoid carcinoma, 75 adenocarcinoma, 15 non-small cell carcinoma, 68 small cell carcinoma and 25 mixed tumors). CT images were obtained of the chest and upper abdomen with intravenous contrast except in patients with a history of allergy or renal insufficiency. The characteristics associated with abdominal CT images aiding or confusing diagnosis were analyzed by Spearman coefficient. Differences related to sex or histology were studied using a Mann-Whitney U-test and Kruskal-Wallis test.

RESULTS

The upper abdominal CT changed the staging of 27 patients (7%): non-small cell carcinoma 5% (16/319) and small-cell carcinoma 16.2% (11/68). Twelve patients (3.1%) showed evidence of unconfirmed adrenal or hepatic metastasis. Change of staging after CT was associated with a high creatinine concentration in blood (p = 0.032), whereas confusion of diagnosis after CT was more common for women (p = 0.002) and patients for whom the diagnosis was established by cytology of sputum or bronchial aspirate (p = 0.019). Differences between men and women were found for from pathology (p = 0.027), confusion after CT (p = 0.002), hemoglobin (p = 0.011), hematocrit (p = 0.019) and smoking (p = 0.000).

CONCLUSION

Given the considerable limitations of CT imaging of the upper abdomen, new technologies should be developed to facilitate a more rational approach to the problem.