Experimentation with and knowledge regarding water-pipe tobacco smoking among medical students at a major university in Brazil,

OBJECTIVE:

Water-pipe tobacco smoking is becoming increasingly more common among young people. The objective of this study was to estimate the prevalence of the use of water pipes and other forms of tobacco use, including cigarette smoking, among medical students, as well as to examine the attitudes, beliefs, and knowledge of those students regarding this issue.

METHODS:

We administered a questionnaire to students enrolled in the University of São Paulo School of Medicine, in São Paulo, Brazil. The respondents were evaluated in their third and sixth years of medical school, between 2008 and 2013. Comparisons were drawn between the two years.

RESULTS:

We evaluated 586 completed questionnaires. Overall, the prevalence of current cigarette smokers was low, with a decline among males (9.78% vs. 5.26%) and an increase among females (1.43% vs. 2.65%) in the 3rd and 6th year, respectively. All respondents believed that health professionals should advise patients to quit smoking. However, few of the medical students who smoked received physician advice to quit. Experimentation with other forms of tobacco use was more common among males (p<0.0001). Despite their knowledge of its harmful effects, students experimented with water-pipe tobacco smoking in high proportions (47.32% and 46.75% of the third- and sixth-year students, respectively).

CONCLUSIONS:

The prevalence of experimentation with water-pipe tobacco smoking and other forms of tobacco use is high among aspiring physicians. Our findings highlight the need for better preventive education programs at medical schools, not only to protect the health of aspiring physicians but also to help them meet the challenge posed by this new epidemic.     

Influence of current or former smoking on asthma management and control

BACKGROUND:

In patients with asthma, smoking has been associated with accelerated decline in pulmonary function, poor disease control and reduced responsiveness to corticosteroids.

OBJECTIVE:

To assess the influence of current and former smoking on self-reported asthma control and health care use in a large population of asthma patients.

METHODS:

The present analysis was conducted following a telephone survey of adult Canadians aged 18 to 54 years who had physician-diagnosed asthma and a smoking history of less than 20 pack-years.

RESULTS:

Of 893 patients, 268 were former smokers and 108 were current smokers. Daytime and nighttime symptoms, absenteeism from work or school, emergency care use for asthma in the past year, and use of a short-acting bronchodilator without controller medication were reported more frequently by current smokers than non-smokers and former smokers. Former smokers were not significantly different from nonsmokers with respect to most asthma outcomes.

CONCLUSIONS:

Current smokers with asthma show evidence of poorer asthma control and greater acute care needs than lifelong nonsmokers or former smokers. These observations stress the importance of smoking cessation to help achieve asthma control.     

Nicotine dependence and smoking habits in patients with head and neck cancer

Objective:

To assess smoking habits and nicotine dependence (ND) in patients with head and neck cancer

Methods:

This study involved 71 smokers or former smokers with squamous cell carcinoma in the oral cavity, pharynx, or larynx who were treated at a university hospital in the city of São Paulo between January and May of 2010. We used the Fagerström Test for Nicotine Dependence to evaluate smoking habits and ND in the sample. Data regarding cancer treatment were collected from medical records. Depending on the variables studied, we used the chi-square test, Fisher''s exact test, Student''s t-test, or Spearman''s correlation test.

Results:

Of the 71 patients, 47 (66.2%) presented with high or very high ND, 40 (56.3%) smoked more than 20 cigarettes/day, and 32 (45.1%) smoked their first cigarette within 5 min of awakening. Advanced disease stage correlated significantly with the number of cigarettes smoked per day (p = 0.011) and with smoking history (p = 0.047). We found that ND did not correlate significantly with gender, disease stage, smoking cessation, or number of smoking cessation attempts, nor did the number of cigarettes smoked per day correlate with smoking cessation or gender. Treatment for smoking cessation was not routinely offered.

Conclusions:

In most of the patients studied, the level of ND was high or very high. The prevalence of heavy smoking for long periods was high in our sample. A diagnosis of cancer is a motivating factor for smoking cessation. However, intensive smoking cessation treatment is not routinely offered to smoking patients diagnosed with cancer.     

Psychological morbidity as a moderator of intention to quit smoking: a study of smokers and former smokers

OBJECTIVE:

To analyze psychological morbidity as a moderator of the relationship between smoking representations and quality of life in smokers and former smokers, as well as to determine which psychological variables discriminate between smokers with and without the intention to quit smoking.

METHODS:

This was a quantitative, correlational cross-sectional study involving a convenience sample of 224 smokers and 169 former smokers.

RESULTS:

In smokers and former smokers, psychological morbidity had a moderating effect on the relationship between mental/physical quality of life and smoking representations (cognitive representations, emotional representations, and comprehensibility). Smokers with the intention to quit smoking more often presented with low comprehensibility, threatening emotional representations, behavioral beliefs, and perceived behavioral control, as well as with normative/control beliefs, than did those without the intention to quit.

CONCLUSIONS:

The results of this study underscore the importance of the moderating effect exerted by psychological morbidity, as well as that of sociocognitive variables, among smokers who have the intention to quit smoking.     

Correlates of experimentation with smoking and current cigarette consumption among adolescents

OBJECTIVE:

The aim of this study was to analyze social characteristics and stress as correlates of cigarette smoking in adolescence. The main intent was to identify elements that distinguish adolescents who had experimented with smoking and did not progress to regular smoking from those who became current smokers.

METHODS:

Students at 10 high schools in the city of Ribeirão Preto, Brazil, completed a questionnaire based on an instrument employed in a similar large-scale study. The students were classified as never-smokers or experimenters. The experimenters were subcategorized as having become current smokers or nonprogressors. Analyses were performed using adjusted logistic models.

RESULTS:

A total of 2,014 students (mean age, 16.2 ± 1.1 years; females, 53%) completed the questionnaire. We categorized 1,283 students (63.7%) as never-smokers, 244 (12.1%) as current smokers, and 487 (24.2%) as nonprogressors. We found that experimentation with smoking was associated with being held back a grade in school (OR = 1.80), alcohol intake (low/occasional, OR = 8.92; high/regular, OR = 2.64), illicit drug use (OR = 9.32), having a sibling or cousin who smokes (OR = 1.39), having a friend who smokes (OR = 2.08), and high levels of stress (in females only, OR = 1.32). Factors associated with an increased risk of transitioning from experimenter to current smoker were alcohol intake (low/occasional, OR = 3.28; high/regular, OR = 2.16), illicit drug use (OR = 3.61), and having a friend who smokes (OR = 7.20).

CONCLUSIONS:

Current smoking was associated with a profile of socioeconomic correlates different from that associated with experimentation only. Our data (showing that current smoking was associated with having a friend who smokes, alcohol intake, and illicit drug use) suggest the need for comprehensive approaches to discourage substance use during adolescence.     

Preventing smoking during pregnancy: the importance of maternal knowledge of the health hazards and of the treatment options available

OBJECTIVE:

To examine the pattern of tobacco use and knowledge about tobacco-related diseases, as well as to identify popular types of electronic media, in pregnant women, in order to improve strategies for the prevention or cessation of smoking among such women.

METHODS:

A cross-sectional study involving 61 pregnant women, seen at primary care clinics and at a university hospital, in the city of Botucatu, Brazil. For all subjects, we applied the Hospital Anxiety and Depression Scale. For subjects with a history of smoking, we also applied the Fagerström Test for Nicotine Dependence, and we evaluated the level of motivation to quit smoking among the current smokers.

RESULTS:

Of the 61 pregnant women evaluated, 25 (40.9%) were smokers (mean age, 26.4 ± 7.4 years), 24 (39.3%) were former smokers (26.4 ± 8.3 years), and 12 (19.8%) were never-smokers (25.1 ± 7.2 years). Thirty-nine women (63.9%) reported exposure to passive smoking. Of the 49 smokers/former smokers, 13 (26.5%) were aware of the pulmonary consequences of smoking; only 2 (4.1%) were aware of the cardiovascular risks; 23 (46.9%) believed that smoking does not harm the fetus or newborn infant; 21 (42.9%) drank alcohol during pregnancy; 18 (36.7%) reported increased cigarette consumption when drinking; 25 (51.0%) had smoked flavored cigarettes; and 12 (24.5%) had smoked a narghile. Among the 61 pregnant women evaluated, television was the most widely available and favorite form of electronic media (in 85.2%), as well as being the form most preferred (by 49.2%).

CONCLUSIONS:

Among pregnant women, active smoking, passive smoking, and alternative forms of tobacco consumption appear to be highly prevalent, and such women seem to possess little knowledge about the consequences of tobacco use. Educational programs that include information about the consequences of all forms of tobacco use, employing new and effective formats tailored to this particular population, should be developed, in order to promote smoking prevention and cessation among pregnant women. Further samples to explore regional and cultural adaptations should be evaluated.     

Airflow obstruction in young adults in Canada

OBJECTIVE:

Airflow obstruction is relatively uncommon in young adults, and may indicate potential for the development of progressive disease. The objective of the present study was to enumerate and characterize airflow obstruction in a random sample of Canadians aged 20 to 44 years.

SETTING:

The sample (n=2962) was drawn from six Canadian sites.

DESIGN:

A prevalence study using the European Community Respiratory Health Survey protocol was conducted. Airflow obstruction was assessed by spirometry. Bronchial responsiveness, skin reactivity to allergens and total serum immunoglobulin E were also measured. Logistic regression was used for analysis.

RESULTS:

Airflow obstruction was observed in 6.4% of the sample, not associated with sex or age. The risk of airflow obstruction increased in patients who had smoked and in patients who had lung trouble during childhood. Adjusted for smoking, the risk of airflow obstruction was elevated for subjects with past and current asthma, skin reactivity to allergens, elevated levels of total immunoglobulin E and bronchial hyper-responsiveness. Of the subjects with airflow obstruction, 21% were smokers with a history of asthma, 50% were smokers without asthma, 12% were nonsmokers with asthma and 17% were nonsmokers with no history of asthma. Bronchial hyper-responsiveness increased the prevalence of airflow obstruction in each of these groups.

CONCLUSION:

Smoking and asthma, jointly and individually, are major determinants of obstructive disorders in young adults. Bronchial hyper-responsiveness contributes to obstruction in both groups.     

Pulmonary tuberculosis and lung cancer: simultaneous and sequential occurrence

OBJECTIVE:

Lung cancer (LC) is the leading cause of cancer-related death and represents a major public health problem worldwide. Another major cause of morbidity and mortality, especially in developing countries, is tuberculosis. The simultaneous or sequential occurrence of pulmonary tuberculosis and LC in the same patient has been reported in various case series and case-control studies. The objective of this study was to describe the characteristics of patients developing tuberculosis and LC, either simultaneously or sequentially.

METHODS:

This was a cross-sectional study based on the review of medical charts.

RESULTS:

The study involved 24 patients diagnosed with tuberculosis and LC between 2009 and 2012. The diagnoses of tuberculosis and LC occurred simultaneously in 10 patients, whereas tuberculosis was diagnosed prior to LC in 14. The median time between the two diagnoses was 5 years (interquartile range: 1-30 years). Fourteen patients (58.3%) were male, 20 (83.3%) were White, and 22 (91.7%) were smokers or former smokers. The most common histological type was adenocarcinoma, identified in 14 cases (58.3%), followed by epidermoid carcinoma, identified in 6 (25.0%). Seven patients (29.2%) presented with distant metastases at diagnosis; of those 7 patients, 5 (71%) were diagnosed with LC and tuberculosis simultaneously.

CONCLUSIONS:

In the present study, most of the patients with tuberculosis and LC were smokers or former smokers, and tuberculosis was diagnosed either before or simultaneously with LC. Non-small cell lung cancer, especially adenocarcinoma, was the most common histological type.     

Post-Acute Coronary Syndrome Alcohol Abuse: Prospective Evaluation in the ERICO Study

Background

Some studies have indicated alcohol abuse as one of the contributors to the development of cardiovascular disease, particularly coronary heart disease. However, this relationship is controversial.

Objective

To investigate the relationship between post-acute coronary syndrome (ACS) alcohol abuse in the Acute Coronary Syndrome Registry Strategy (ERICO Study).

Methods

146 participants from the ERICO Study answered structured questionnaires and underwent laboratory evaluations at baseline, 30 days and 180 days after ACS. The Alcohol Use Disorders Identification Test (AUDIT) was applied to assess harmful alcohol consumption in the 12 months preceding ACS (30 day-interview) and six months after that.

Results

The frequencies of alcohol abuse were 24.7% and 21.1% in the 12 months preceding ACS and six months after that, respectively. The most significant cardiovascular risk factors associated with high-risk for alcohol abuse 30 days after the acute event were: male sex (88.9%), current smoking (52.8%) and hypertension (58.3%). Six months after the acute event, the most significant results were replicated in our logistic regression, for the association between alcohol abuse among younger individuals [35-44 year-old multivariate OR: 38.30 (95% CI: 1.44-1012.56) and 45-54 year-old multivariate OR: 10.10 (95% CI: 1.06-96.46)] and for smokers [current smokers multivariate OR: 51.09 (95% CI: 3.49-748.01) and past smokers multivariate OR: 40.29 (95% CI: 2.37-685.93)].

Conclusion

Individuals younger than 54 years and smokers showed a significant relation with harmful alcohol consumption, regardless of the ACS subtype.     

Cigarette smoking and the association with glomerular hyperfiltration and proteinuria in healthy middle-aged men

Summary

Background and objectives

Glomerular hyperfiltration and albuminuria accompanied by early-stage diabetic kidney disease predict future renal failure. Cigarette smoking has reported to be associated with elevated GFR in cross-sectional studies and with renal deterioration in longitudinal studies. The degree of glomerular hyperfiltration and proteinuria associated with smoking, which presumably is a phenomenon of early renal damage, has not been investigated in a satisfying manner so far.

Design, setting, participants, & measurements

This study included 10,118 Japanese men aged 40 to 55 years without proteinuria or renal dysfunction at entry. Estimated GFR was calculated using the Modification of Diet in Renal Disease equation for Japanese. Glomerular hyperfiltration was defined as estimated GFR ≥117.0 ml/min per 1.73 m², which was the upper 2.5th percentile value of estimated GFR in the total population. Proteinuria was detected using standard dipstick.

Results

During the 6-year observation period, there were 449 incident cases of glomerular hyperfiltration and 1653 cases of proteinuria. Current smokers had a 1.32-time higher risk for the development of glomerular hyperfiltration and a 1.51-time higher risk for proteinuria than nonsmokers after adjustment for baseline age, body mass index, systolic and diastolic BP, antihypertensive medication, diabetes, alcohol consumption, regular leisure-time physical activity, and estimated GFR. Both daily and cumulative cigarette consumption were associated with an increased risk for glomerular hyperfiltration and proteinuria in a dose-response manner.

Conclusions

In middle-aged Japanese men, smoking was associated with an increased risk of glomerular hyperfiltration and dipstick proteinuria. Of importance, past smokers did not exhibit any increased risk for these conditions.     

Association between serum selenium level and conversion of bacteriological tests during antituberculosis treatment

Objective:

To determine whether serum selenium levels are associated with the conversion of bacteriological tests in patients diagnosed with active pulmonary tuberculosis after eight weeks of standard treatment.

Methods:

We evaluated 35 healthy male controls and 35 male patients with pulmonary tuberculosis, the latter being evaluated at baseline, as well as at 30 and 60 days of antituberculosis treatment. For all participants, we measured anthropometric indices, as well as determining serum levels of albumin, C-reactive protein (CRP) and selenium. Because there are no reference values for the Brazilian population, we used the median of the serum selenium level of the controls as the cut-off point. At 30 and 60 days of antituberculosis treatment, we repeated the biochemical tests, as well as collecting sputum for smear microscopy and culture from the patients.

Results:

The mean age of the patients was 38.4 ± 11.4 years. Of the 35 patients, 25 (71%) described themselves as alcoholic; 20 (57.0%) were smokers; and 21 (60.0%) and 32 (91.4%) presented with muscle mass depletion as determined by measuring the triceps skinfold thickness and arm muscle area, respectively. Of 24 patients, 12 (39.2%) were classified as moderately or severely emaciated, and 15 (62.5%) had lost > 10% of their body weight by six months before diagnosis. At baseline, the tuberculosis group had lower serum selenium levels than did the control group. The conversion of bacteriological tests was associated with the CRP/albumin ratio and serum selenium levels 60 days after treatment initiation.

Conclusions:

Higher serum selenium levels after 60 days of treatment were associated with the conversion of bacteriological tests in pulmonary tuberculosis patients.     

Smoking-Cessation Efforts by US Adult Smokers with Medical Comorbidities

Background

Continued cigarette smoking by individuals with chronic medical diseases can adversely affect their symptoms, disease progression, and mortality. We assessed the association between medical comorbidities and smoking-cessation efforts among US adult smokers.

Differences in clinical presentation of non-small cell lung cancer in never-smokers versus smokers

Objectives

This study was conducted to evaluate whether or not tumor spread and the diagnostic process in non-small cell lung cancer (NSCLC) is different based on smoking history.

Methods

Associations between smoking status and clinical presentation were evaluated controlling for the effect of histology. Lung cancer with delayed diagnosis (LCDD) and incidental detection (LCID) were determined based on medical records.

Results

Of 914 patients, frequency of distant metastases was more common in never-smokers than in smokers (59% and 36%, respectively; P<0.001). Although never-smokers were more likely to have LCDD than smokers (18% and 11%, respectively; P=0.038), LCDD were not significantly associated with frequency of distant metastases [49% (LCDD) vs. 42% (non-LCDD); P=0.189] as well as tumor [29% (T3-4) vs. 24% (T1-2); P=0.134] and node [43% (N2-3) vs. 44% (N0-1); P=0.838] stage. Interestingly, never-smokers are more likely to have LCID than smokers (31% and 19%, respectively; P=0.010). In survival analysis, LCID (P=0.001; HR, 0.63) remained a prognostic factor, while LCDD did not.

Conclusions

This study suggests distinct metastatic pattern and diagnostic processes of never-smokers. The link between survival and incidental detection was also indicated.KEYWORDS : Non-small cell lung cancer (NSCLC), advanced stage, incidental detection, smoking history     

Prevalence of nutritional deficiency in patients with pulmonary tuberculosis

OBJECTIVE:

To determine the prevalence of nutritional deficiency among patients with pulmonary tuberculosis.

METHODS:

This was a cross-sectional study using data obtained from the Brazilian Case Registry Database and from the medical records of patients diagnosed with pulmonary tuberculosis (15-59 years of age) residing in one of the municipalities that make up the 16th Regional Health District of the state of Bahia. We calculated the incidence, lethality, and mortality rates, as well as the prevalence of nutritional deficiency, as evaluated by body mass index. Demographic, social, clinical, and epidemiological data were collected.

RESULTS:

Of the 72 confirmed cases of tuberculosis, 59 (81.9%) were in males, and 21 (29.2%) of the patients were in the 40-49 year age bracket. The majority (85.3%) described themselves as Mulatto or Black; 55.2% reported using alcohol; and approximately 90% were treated as outpatients. In the district and age bracket studied, the incidence of pulmonary tuberculosis was 30.6/100,000 population. Among the 72 patients, data regarding nutritional status was available for 34. Of those, 50% and 25%, respectively, presented nutritional deficiency at the beginning and at the end of treatment. No statistically significant differences were found between normal-weight and malnourished patients regarding the characteristics studied.

CONCLUSIONS:

The prevalence of nutritional deficiency was high among our sample of patients with pulmonary tuberculosis. This underscores the importance of nutritional follow-up for the assessment of tuberculosis treatment in the decision-making process regarding therapeutic interventions.     

HAV Immunity in Iranian Medical Students

Background:

Hepatitis A, a fecal-oral transmitted disease, which has been considered endemic in developing countries, seems to change its pattern in developing countries because of their improved socioeconomic status.

Objectives:

In the present study, we aimed to determine the need of vaccination in 270 students at AJA University of Medical Sciences.

Materials and Methods:

The serum level of anti-HAV antibody was checked in 270 students of AJA University of medical students, and effect of different factors, including age, gender, pre-university entrance exam region, familial education, familial income, clean water availability, and previous history of jaundice were tested.

Results:

Of total 270 students, 30 were female. Their age ranged between 18 and 30 years old with the mean age of 20.58 years and just 34% of students had positive level of anti-HAV antibody. Age and sex had no role in positive serum level of anti-HAV antibody. According to analyzed data, lack of clean water availability, pre-university entrance exam region, lower family education, and poor health status estimation increased statistically the risk of HAV infection.

Conclusions:

Because 66% of students were anti-HAV antibody negative and they will work as health care workers in future, our study suggest vaccinating all students accepted at AJA University of Medical Sciences.     

Prevalence of Rheumatic Heart Disease in a Public School of Belo Horizonte

Background

Previous studies indicate that compared with physical examination, Doppler echocardiography identifies a larger number of cases of rheumatic heart disease in apparently healthy individuals.

Objectives

To determine the prevalence of rheumatic heart disease among students in a public school of Belo Horizonte by clinical evaluation and Doppler echocardiography.

Methods

This was a cross-sectional study conducted with 267 randomly selected school students aged between 6 and 16 years. students underwent anamnesis and physical examination with the purpose of establishing criteria for the diagnosis of rheumatic fever. They were all subjected to Doppler echocardiography using a portable machine. Those who exhibited nonphysiological mitral regurgitation (MR) and/or aortic regurgitation (AR) were referred to the Doppler echocardiography laboratory of the Hospital das Clínicas of the Universidade Federal of Minas Gerais (HC-UFMG) to undergo a second Doppler echocardiography examination. According to the findings, the cases of rheumatic heart disease were classified as definitive, probable, or possible.

Results

Of the 267 students, 1 (0.37%) had a clinical history compatible with the diagnosis of acute rheumatic fever (ARF) and portable Doppler echocardiography indicated nonphysiological MR and/or AR in 25 (9.4%). Of these, 16 (6%) underwent Doppler echocardiography at HC-UFMG. The results showed definitive rheumatic heart disease in 1 student, probable rheumatic heart disease in 3 students, and possible rheumatic heart disease in 1 student.

Conclusion

In the population under study, the prevalence of cases compatible with rheumatic involvement was 5 times higher on Doppler echocardiography (18.7/1000; 95% CI 6.9/1000-41.0/1000) than on clinical evaluation (3.7/1000-95% CI).     

Applicability of the Appropriate use Criteria for Myocardial Perfusion Scintigraphy

Background

Appropriateness Criteria for nuclear imaging exams were created by American College of Cardiology (ACC) e American Society of Nuclear Cardiology (ASNC) to allow the rational use of tests. Little is known whether these criteria have been followed in clinical practice.

Objective

To evaluate whether the medical applications of myocardial perfusion scintigraphy (MPS) in a private nuclear medicine service of a tertiary cardiology hospital were suitable to the criteria of indications proposed by the American medical societies in 2005 and 2009 and compare the level of indication of both.

Methods

We included records of 383 patients that underwent MPS, November 2008 up to February 2009. Demographic characteristics, patient''s origin, coronary risk factors, time of medical graduation and appropriateness criteria of medical applications were studied. The criteria were evaluated by two independent physicians and, in doubtful cases, defined by a medical expert in MPS.

Results

Mean age was 65 ± 12 years. Of the 367 records reviewed, 236 (64.3%) studies were performed in men and 75 (20.4%) were internee. To ACC 2005, 255 (69.5%) were considered appropriate indication and 13 (3.5%) inappropriate. With ACC 2009, 249 (67.8%) were considered appropriate indications and 13 (5.2%) inappropriate.

Conclusions

We observed a high rate of adequacy of medical indications for MPS. Compared to the 2005 version, 2009 did not change the results.     

Smoking Cessation Among Women with and at Risk for HIV: Are They Quitting?

BACKGROUND

Cigarette smoking is an important risk factor for adverse health events in HIV-infected populations. While recent US population-wide surveys report annual sustained smoking cessation rates of 3.4–8.5%, prospective data are lacking on cessation rates for HIV-infected smokers.

OBJECTIVE

To determine the sustained tobacco cessation rate and predictors of cessation among women with or at risk for HIV infection.

DESIGN

Prospective cohort study.

PARTICIPANTS

A total of 747 women (537 HIV-infected and 210 HIV-uninfected) who reported smoking at enrollment (1994–1995) in the Women’s Interagency HIV Study (WIHS) and remained in follow-up after 10 years. The participants were mostly minority (61% non-Hispanic Blacks and 22% Hispanics) and low income (68% with reported annual incomes of less than or equal to $12,000).

MEASUREMENTS AND MAIN RESULTS

The primary outcome was defined as greater than 12 months continuous cessation at year 10. Multivariate logistic regression was used to identify independent baseline predictors of subsequent tobacco cessation. A total of 121 (16%) women reported tobacco cessation at year 10 (annual sustained cessation rate of 1.8%, 95% CI 1.6–2.1%). Annual sustained cessation rates were 1.8% among both HIV-positive and HIV-negative women (p = 0.82). In multivariate analysis, the odds of tobacco cessation were significantly higher in women with more years of education (p trend = 0.02) and of Hispanic origin (OR = 1.87, 95% CI = 1.4–2.9) compared to Black women. Cessation was significantly lower in current or former illicit drug users (OR = 0.42 95% CI = 0.24–0.74 and OR = 0.65, 95% CI = 0.49–0.86, respectively, p trend = 0.03) and women reporting a higher number of cigarettes per day at baseline (p trend < 0.001).

CONCLUSIONS

HIV-infected and at-risk women in this cohort have lower smoking cessation rates than the general population. Given the high prevalence of smoking, the high risk of adverse health events from smoking, and low rates of cessation, it is imperative that we increase efforts and overcome barriers to help these women quit smoking.KEY WORDS: smoking cessation, HIV/AIDS, clinical epidemiology, vulnerable populations     

Effects of long-term smoking on the activity and mRNA expression of CYP isozymes in rats

Background

To investigate the effect of long-term smoking on the activity and mRNA expression of cytochrome P450 (CYP) enzymes.

Methods

Sprague-Dawley rats were exposed to passive smoking 6 cigarettes per day for 180 days. A cocktail solution which contained phenacetin (20 mg/kg), tolbutamide (5 mg/kg), chlorzoxazone (20 mg/kg) and midazolam (10 mg/kg) was given orally to rats. Blood samples were collected at pre-specified time points and the concentrations of probe drugs in plasma were determined by HPLC-MS/MS. The corresponding pharmacokinetic parameters were calculated by DAS 3.0. In addition, real-time RT-PCR was used to analyze the mRNA expression of CYP1A2, CYP2C11, CYP2E1 and CYP3A1 in rat liver.

Results

There were no significant influences of pharmacokinetic profiles of chlorzoxazone in long-term smoking pretreated rats. But many pharmacokinetic profiles of phenacetin, tolbutamide, and midazolam in long-term smoking pretreated rats were affected significantly (P<0.05). The results suggested that long-term smoking had significant inhibition effects on CYP2C11 and CYP3A1 while CYP1A2 enzyme activity was induced. Furthermore, Long-term smoking had no effects on rat CYP2E1. The mRNA expression results were consistent with the pharmacokinetic results.

Conclusions

Alterations of CYP450 enzyme activities may fasten or slow down excretion with corresponding influence on drug efficacy or toxicity in smokers compared to nonsmokers, which may lead to clinical failures of lung cancer therapy or toxicity in smokers.