Alternative forms of tobacco use.

BACKGROUND: A review of the available scientific literature concerning forms of tobacco use other than regular cigarettes, cigars and pipes, the nature of such products, prevalence data and trends, health effects, regulatory issues and preventive measures. RESULTS: Narghile (water pipe), bidis, kreteks and other forms of oral tobacco are traditionally used in many low-income countries, and some of these are currently spreading to the Western countries. They are all linked to negative effects similar to, and often greater than, those associated with common cigarette smoking. Various potentially reduced exposure products (PREPs), including snus, targeted at smokers aware of the health risks of regular cigarettes, have recently been developed by the tobacco industry. Their pathogenic potential varies widely and is not fully known; it is in any case greater than that of pure nicotine forms (such as medicinal nicotine). Their use as cigarette substitutes should not be considered even by inveterate smokers who are unable or unwilling to quit nicotine before further independent evaluation and control. CONCLUSIONS: There is no such thing as a safe tobacco product. Like cigarettes, alternative forms of tobacco use need regulatory measures that are adapted to local situations and supplemented by preventive measures within the World Health Organization's Framework Convention for Tobacco Control.

What can be learnt from tobacco butts? An observational study in a realistic hospital setting.

OBJECTIVE: Examination of tobacco butts and its possible use in tobacco control. DESIGN: Macroscopic examination of cigarette butts collected outside or in dedicated smoking rooms of a smoke-free hospital. RESULTS: Of 925 butts, 3.8% were cigarillos, 11.1% cigarettes without filter, 57.7% ventilated filter cigarettes, 22.5% filter cigarettes without macroscopic ventilation and 4.9% undetermined. Thirty-six different cigarette brands were identified. A wide distribution of butt lengths (mean 32.1 mm, variation coefficient 28%), peripheral ovalisation of the filter in 83.9%, and extended browning of the mouth end of the filter in 48.6% were observed. Vent holes were macroscopically detectable in 70.5% and a sharp decrease in browning in 53.4% of the filter cigarettes. Most (94.7%) ventilation holes were located at > or =10 mm from the mouth end. CONCLUSIONS: In a smoke-free hospital, the use of tobacco products (mainly ventilated filter cigarettes) remains sizeable. Given the wide distribution of butt lengths, the number of cigarettes per day is a poor marker of toxin intake. Vent-hole localisation and signs of vent-blocking confirm the inadequacy of machine-measured smoke yields and the presence of compensatory smoking. More intensive individual cessation advice with pharmacological support is necessary. Examination of a smoker's own cigarette butts can be used as a tool for individual cessation advice.

Anti-A60 immunoglobulin G in the serodiagnosis of tuberculosis in HIV-seropositive and seronegative patients.

OBJECTIVE: A60 is a high molecular weight mycobacterial antigen complex. The detection of immunoglobulin (Ig) G antibodies to A60 has been advocated as a reasonably sensitive and specific test for active tuberculosis (TB). We aimed to compare the sensitivity of this test among HIV-seropositive and HIV-seronegative patients with pulmonary TB. METHODS: The presence and concentration of anti-A60 IgG antibodies was assessed by enzyme-linked immunosorbent assay in 208 HIV-seropositive and 91 HIV-seronegative Zaïrian patients with smear-positive pulmonary TB. The relationship between anti-A60 IgG levels and HIV serostatus, CD4+ lymphocyte counts, presence of clinical AIDS, and tuberculin skin test results was verified. RESULTS: Only 36.5% of the HIV-seropositive, compared with 69.2% of the HIV-seronegative patients had a positive anti-A60 IgG test (P < 0.00001). Among HIV-seropositive patients, anti-A60 IgG levels did not differ according to CD4+ lymphocyte counts, presence of clinical AIDS, or tuberculin skin test results. CONCLUSIONS: Among patients with pulmonary TB, the sensitivity of testing for anti-A60 IgG was much lower among HIV-seropositive than among HIV-seronegative patients, even from the early stages of HIV-related immunodeficiency. This limits the utility of anti-A60 IgG-antibody testing in the diagnosis of TB among HIV-infected patients.

Towards a tobacco-free world.

Many barriers must be tackled for controlling the tobacco epidemic responsible for completely preventable mortality. Tobacco addiction is presently considered as the central element in smoking. The mechanisms of action of drugs of abuse (including nicotine) and the current techniques for their study in animals and in humans are briefly reviewed. Cigarettes are manipulated by the tobacco industry to increase the level of dependence. The transnational tobacco companies use a global tactic to expand their sales, particularly in the third world, so that the mean world cigarette consumption per adult remains unchanged at approximately 1500 per year. Nevertheless, it is hoped that control of the epidemic will be gained in the 21st century, since the awareness of tobacco risks and costs is increasing, an antismoking climate is developing and the tobacco lobby has lost its credibility. On the other hand, improved behavioural and pharmacological methods increase the cessation rate. Health professionals are progressively more involved in the smoking cessation problems, while international control measures are applied by the European Commission. The World Health Organization is preparing a "Framework Convention on Tobacco Control" with binding mechanisms for governments. A larger involvement of the community is needed to promote an international policy based on health values, rather than on trade considerations, and addressing the specific problems of the third world. Nevertheless, since a latency of approximately 30 yrs exists between the increase in tobacco consumption in a population and the rise in tobacco mortality, past trends in consumption will continue to influence health status during the next 30 yrs. Present, urgently needed, radical health measures are expected to have their major impact only after that period.

[Nicotine substitution as an aid in smoking cessation. Mechanisms of action, methods and evaluation of the results]. / La substitution nicotinique dans l'aide au sevrage tabagique. Modes d'action, modalités et appréciation des résultats.

Failure in smoking cessation is linked with behavioural factors and with nicotine dependence, due to the psychoactive effects of the drug, mainly on locus ceruleus and on mesolimbic dopaminergic system. Nicotine substitution partially controls the withdrawal syndrome, sometimes very intense in smokers with pharmacological dependence. After transdermal nicotine administration, nicotine blood levels are relatively low but steady; nicotine chewing gum can be used alone or in combination with transdermal administration. Both methods can double biologically controlled success rates. Risks are limited in comparison with those of continued smoking. Recent data from the literature allow a better understanding of indications and limits of the pharmacological approach to cessation, that should address smokers firmly decided to stop, and be completed by behavioural support, including changes in the way of life.

The cost-effectiveness of an extended course (12+12 weeks) of varenicline plus brief counselling compared with other reimbursed smoking cessation interventions in Belgium, from a public payer perspective.

OBJECTIVE: To evaluate the cost-effectiveness of an extended (12+12 weeks) course of varenicline plus brief counselling compared with the currently reimbursed smoking cessation interventions (in combination with brief counselling) in Belgium, from a public payer perspective. METHODS: The previously published version of the BENESCO model which included the extended course of varenicline was updated with recent publically available demographic and cost data from Belgium. RESULTS: The extended course of varenicline plus brief counselling has an incremental cost per quality adjusted life year gained of 1101€ compared with a nonextended 12-week course of varenicline (plus brief counselling). The extended course of varenicline dominates all other comparators in this analysis. CONCLUSIONS: The extended course of varenicline (12 weeks followed by 12 weeks maintenance therapy in successful quitters) plus brief counselling is a highly cost-effective alternative to a non-extended (12 weeks only) course of varenicline plus brief counselling. This strategy dominates the other alternative smoking cessation interventions currently reimbursed in Belgium.

Quantification and chemical markers of tobacco-exposure.

Quantitation of exposure to tobacco products is useful for any individual smoker, and necessary for epidemiological studies which relate smoking to pathology, or which are concerned with the efficacy of smoking cessation methods. The medical history, trying to quantitate the current mean daily cigarette consumption (consumption rate), the cumulative risk (pack years) and the various types of smoking, including inhalation habits, should also be attempted. However, due to the quasi-systematic underrating of tobacco consumption which smokers have revealed on many occasions, together with difficulty in correctly observing cigarette smoking, objective validation of recent historical data by quantitative measurement of tobacco products in tissue fluids is mandatory. Measurements of nicotine and cotinine levels in serum and urine require elaborate and expensive methods, and are not adequate for validation of smoking cessation in smokers who are using nicotine chewing gum. Carbon monoxide is a good marker of smoke inhalation. Normal carboxyhaemoglobin levels allow us to confirm that a subject has recently stopped smoking, as its half-life is only a few hours in blood. Salivary (or plasma) measurements of thiocyanate discriminate between smokers and ex-smokers, with a high probability, particularly in those who have stopped smoking for at least 14 days, separating these clearly from current smokers. However, several potential causes of error must be considered to allow correct interpretation of measurements of thiocyanate.

Pharmacological approach to smoking cessation.

At present, the possibilities of pharmacological intervention in smoking cessation remain limited. Some products, like smoking deterrants, lobeline, amphetamine and sedatives, definitely seem to have been rejected. The efficiency of other drugs aiming to treat the withdrawal syndrome (e.g. clonidine) or to eradicate the smoking habit (e.g. mecamylamine) must still be confirmed in large controlled trials. The same is true of the "cigarette substitutes" which have appeared recently. The only effective substitute treatment currently available is nicotine, presented as nicotine gum; other modalities of administration of nicotine are in preparation. Even if it has not fulfilled all the expectations of its promoters and of the smokers who hoped for a panacea, nicotine gum, when administered to highly dependent smokers motivated to stop, with the appropriate technique, effects a moderate increase not only in the cessation rate but also in the long-term abstention rate, in so far as the necessary psychological support is provided, either by the physician in medical settings, or by other health professionals, in smoking-cessation clinics or in industrial and community settings. The addiction to psychoactive nicotine presents only one facet of the smoking process in chronic smokers. They must also be helped to face the behavioural components of their habits, so individualized counselling remains essential, in addition to the prescription of the gum, in order to achieve satisfactory rates of long-term smoking cessation.

Influence of hyposensitization with Dermatophagoides pteronyssinus extract on clinical score, total and specific IgE levels, and skin test in asthmatic patients.

To evaluate the effects of immunotherapy on clinical response, on IgE serum level, on radioallergosorbent test (RAST), and on skin tests, a prospective study was performed by a follow-up of 73 asthmatic patients allergic for house dust during hyposensitization with Dermatophagoides pteronyssinus extract. No relationship could be found between the evolution of clinical score, skin tests and RAST, but 91% of the patients with a decreasing IgE serum level had satisfactory clinical results. Serial determinations of serum IgE levels during hyposensitization showed two patterns of evolution with a favourable prognostic value: a continuously decreasing serum IgE or a primary increase followed by a late decrease.

Rifampim-combined chemotherapy in coal worker's pneumoconio-tuberculosis.

Results of a retrospective study of rifampin-combined chemotherapy in 59 coal miners with pneumoconio-tuberculosis are reported. In 43 patients pneumoconiosis had attained the stage of progressive massive fibrosis. The follow-up period ranged from 24 to 78 months, except in 8 patients who died before the twenty-fourth month. Twenty-seven of the 59 patients were treated for the first time, and 32 were in retreatment. In none of them had rifampin been administered before. Although the objective was to administer rifampin in combination with one, 2, or even 3 companion drugs that had not been administered before and that had proved to be active on the patients' bacilli in vitro, this goal was fully reached only in the first treatment group; in 8 of the 32 retreated patients the drugs combined with rifampin were considered ineffective. The speed and rate of bacteriologic conversion were most impressive. Sputum conversion was obtained in 90 per cent of the patients; in the initial treatment group 100 per cent of the patients converted their sputum on culture at 5 months and in the retreatment group the corresponding figure was 84.4 per cent. These bacteriologic results are nearly as favorable as those obtained in cases of advanced pulmonary tuberculosis without pneumoconiosis treated with the same rifampin-containing drug regimens. It was concluded that rifampin-combined chemotherapy largely eliminates the handicap caused by the coexistence of tuberculosis and pneumoconiosis. Side effects due to rifampin were without practical significance. In 3 patients of 57 treated with ethambutol, visual impairment was observed. Mortality was high (27 per cent) but was caused by nontuberculous diseases, especially cardiorespiratory insufficiency. In 10 of the 16 patients who died, death occurred after bacteriologic conversion.

[Differential diagnosis of chronic obstructive lung disease, A statistical analysis of the discriminating power of various lung function tests (author's transl)]. / Diagnostic différentiel des bronchopneumopathies obstructives chroniques. Etude statistique du pouvoir discriminatoire de diverses épreuves fonctionnelles respiratoires

Among 65 patients admitted to the hospital for chronic obstructive lung disease, the following pulmonary tests were systematically performed : spirometric vital capacity and total lung capacity, FEV1, functional residual capacity and total lung capacity measured by body plethysmography, airway resistance and specific conductance, CO diffusion capacity measured by single-breath test, N2 clearance by single breath oxygen dilution, and blood gases. The patients were divided into bronchitics, emphysematous and broncho-emphysematous, according to the clinical and radiological Nash's score, and to another personal score derived from the former. The simple and multiple correlations between the clinico-radiological score and the functional results are low. The clustering analysis groups the 65 patients into four clouds of points, around two principal axes : the volume axis and the overinflation axis. This study indicates that the most suggestive results for emphysema diagnosis are increased FRC and TLC and low Tlco/V'a. The clinical score is not dominant for the clustering of the patients into the dynamic clouds. Beneath the bronchitic, the broncho-emphysematous and the emphysematous groups, the clustering analysis individualizes a fourth group of cases characterized by chronic asthma, and which were not isolated by Nash's score.

Evaluation of onset of bronchodilating effect by interruption of the air flow method.

The speed of onset of the bronchodilating effect of ibuterol, a derivative of terbutaline, was measured by the method of air flow interruptions, which enables an almost continuous study of lung resistance before and after the administration of a bronchodilator. In the double-blind comparison between ibuterol and placebo, the onset of action of the new beta 2-agonist has been shown to take place within 30-45 sec. This indicates that ibuterol is a bronchodilator with rapid onset of action.

Early bronchodilating effect of oxitropium bromide in comparison with ipratropium bromide.

The bronchodilating effects of a metered aerosol dose of 40 micrograms ipratropium bromide and of 200 micrograms oxitropium bromide are similar 15 min. after administration. The bronc hodilating activity of ipratropium bromide appears earlier (i.e., 75-90 s after administration) than that of oxitropium bromide but later than that of ibuterol, a beta2-agonist. Ipratropium bromide administered at the close of 80 micrograms provokes a bronchodilation about double of that obtained with 40 micrograms. An adaptation of the usual dosage should be considered.

Long term home oxygen therapy in chronic respiratory care--a Belgian experience in management.

Report on organization, financing, indications, preceding examinations, current observation, practical experiences and results during 2 years of application of oxygen concentrators in long term home treatment of patients with chronic respiratory distress. The authors plead for less restricted indications and propose measures to extend the action area of the patients.

Controlled trial of the effect of repeated administration of ipratropium bromide on ventilatory function of patients with severe chronic airways obstruction.

A trial was designed to assess whether repeated administration of ipratropium bromide for two weeks produced greater improvement than was obtained after a single dose. The effect of ipratropium bromide was compared with that of a placebo during a double-blind cross-over randomized trial in patients with advanced chronic airways disease in a stable state. Ipratropium bromide and placebo were both administered by metered dose inhaler for 14 days. There was a slight statistically significant improvement of conductance, thoracic gas volume, FEV1 and VC after inhalation of ipratropium bromide, but repeated doses of the drug did not produce progressive improvement.

Improvement of oxygen delivery in severe hypoxaemia by a reservoir cannula.

In 36 severely hypoxaemic patients (arterial oxygen tension (PaO2) less than 7.3 kPa or 55 mmHg), candidates for long-term oxygen therapy, we compared the effectiveness of three oxygen-delivery systems, the standard nasal prongs, a so-called oxygen-conserving reservoir device ("Oxymizer Pendant") and the reference pharyngeal catheter, at a preset flow rate of 2 l.min-1. After 30 min, the conserving device (OX) was at least as efficient as the pharyngeal catheter (PC) and did significantly better than the nasal prongs (NP), the mean increments in PaO2 and arterial oxygen saturation (SaO2) being, respectively, 1.1 kPa (8.1 mmHg) and 1.3% higher with OX than with NP. Twenty patients did not reach the target level of 8.6 kPa (65 mmHg) PaO2 with the nasal prongs, but the reservoir cannula allowed nine of these "refractory" patients to hit this therapeutic goal, a result indicating a clear trend towards improved immediate oxygen response. Although initially designed to spare gas, we suggest that a reservoir cannula could serve another purpose, namely to optimize oxygenation in patients treated by an oxygen concentrator. Indeed, since the oxygen flow rate cannot be reliably increased over 3 l.min-1 with the available oxygen concentrators, the reservoir device could be more effective in some selected patients whose hypoxaemia cannot be adequately corrected by standard nasal prongs.

Indoor radon exposure and lung cancer in Belgium.

Indoor radon is the most important source of ionising radiation for the general public and is estimated to be a causal factor for lung cancer. Most risk assessment for low doses are based upon extrapolations of the observations among high exposed groups. As the validity of such procedure is still a controversal matter and in order to obtain direct epidemiological evidence, a case-control study about radon and lung cancer was set-up in southern Belgium. All subjects are recruited at the department of pneumology of the clinic of the catholic university of Louvain at Mont Godinne. In the first year some 130 persons entered the study. Preliminary analysis of the data gives an odds ratio of 4.2 for the exposed group of male smoking cases compared to the matched non exposed control group.

Comparison of the bronchodilating effect of two doses of a sustained release theophylline.

In order to assess the dose/response ratio of two different doses of theophylline, the effects of two periods of 4-day treatment with 300 and 450 mg sustained release anhydrous theophylline (Theodur, Astra, Sweden) b.i.d. in 16 in-patients with reversible chronic obstructive lung disease in a stable state were investigated in a double-blind randomized crossover study. On the 4th day in each treatment period, ventilatory function parameters (FEV1, FVC, PEFR, MEF25, MEF50), theophylline serum concentration and blood gases were measured. Asthma symptoms, beta 2-adrenergic aerosol use significantly different from its value before treatment: the mean FEV1 increase during the 300-mg period reached 12% and during the 450-mg period 15%. The mean difference in theophylline serum concentration between the periods of 300 and 450 mg reached approximately 2 micrograms/ml, but a significant difference could not be demonstrated between both treatment periods, neither in the mean ventilatory parameters, nor in the patients preference. In spite of the use of a sustained release preparation, variations of serum levels of theophylline were observed individually throughout a 12-hour observation period: the extent of those variations differs from one patient to another.

Serological analysis of human tuberculosis by an ELISA with mycobacterial antigen 60.

An ELISA method for detecting serum antibodies against A60, an antigen prepared from the cytoplasm of Mycobacterium bovis BCG, has been applied to 385 subjects, namely 197 controls (neonates, healthy adults, and tuberculin negative, nontuberculous patients), and 188 subjects at various stages of tuberculous infection and disease. Most IgM determinations gave negative results. While the neonates and normal adults had titers of IgG anti-A60 antibodies below the cut off value, wide variations in antibody titers were observed among the various types of subjects infected by M. tuberculosis. The results obtained with nontuberculous subjects were: 100% negative IgG in neonates and healthy adult individuals and 6.4% "false positive" cases among 124 non-tuberculous patients. The percentage of serologically positive cases of tuberculosis was: 5.9% in latent active primary forms, 42.8% in patent active primary forms, and 82.8% in active postprimary forms. Tuberculous infections had a positively rate of 14.7%, while inactive postprimary tuberculosis had a positivity rate of 50%. The results obtained with A60 can favourably be compared with other serum ELISA tests for tuberculous antibodies against purified or semipurified mycobacterial antigens. Anti-A60 ELISA IgG antibody test can be useful to monitor the kinetics of humoral immunological response during tuberculous infection, disease and chemotherapy. A positive IgG ELISA test may support the diagnosis of active tuberculous disease.