Effectiveness of a nicotine patch in helping people stop smoking: results of a randomised trial in general practice. Imperial Cancer Research Fund General Practice Research Group.

OBJECTIVE--To assess the effectiveness of 12 weeks'' treatment with a 24 hour transdermal nicotine patch in helping heavy smokers to stop smoking; also to assess the value of a specially written support booklet about smoking cessation and patch use compared with a simple advice pamphlet. DESIGN--Double blind placebo controlled randomised trial with a 2 x 2 factorial design. SETTING--19 general practices in Oxfordshire. SUBJECTS--1686 heavy smokers aged 25-64 (mean cigarette consumption 24/day; mean duration of smoking 25 years). MAIN OUTCOME MEASURE--Sustained cessation for the last four weeks of the 12 week treatment period, confirmed by saliva cotinine estimation (226/262 cases; 86.3%) or expired carbon monoxide concentration (36/262; 13.7%). Patients lost to follow up (155/1686; 9%) were assumed to have continued to smoke. RESULTS--Cessation was confirmed in 163 patients (19.4%) using the nicotine patch and 99 patients (11.7%) using the placebo patch (difference 7.6% (95% confidence interval 4.2% to 11.1%); p < 0.0001). There was no significant advantage in using the more detailed written support material. The most important adverse effect of the patch was local skin irritation, which occurred in 15.8% (133/842) and 5.1% (43/844) of patients using the nicotine and placebo patches respectively, was graded as severe in 4.8% (40) and 1.1% (nine), and was stated as a reason for withdrawal from the trial in 9.5% (80) and 2.8% (24). CONCLUSION--Nicotine patches are effective in a general practice setting with nursing support, but the extent to which this effect is sustained cannot be assessed until the results of longer term follow up are known.     

Placebo controlled trial of nicotine chewing gum in general practice.

Of 2110 adult cigarette smokers originally recruited to a study of the effect of antismoking advice in general practice, 429 who reported at follow up after one year that they had tried unsuccessfully to stop smoking were offered "a special antismoking chewing gum," either nicotine gum or a placebo gum, in a double blind study. Of 200 who were willing to try the gum, 101 were randomly allocated to the nicotine gum and 99 to the placebo gum. They were followed up at six months by an unannounced home visit, at which they were interviewed and asked to provide a breath sample for analysis of carbon monoxide. Twenty five claimed that they had stopped smoking, but, of them, seven exhaled levels of carbon monoxide indicative of continued smoking. Of the 18 in whom giving up smoking was validated, 10 had received active gum and eight placebo gum, a difference which was not significant (odds in favour of nicotine gum = 1.25, 95% confidence limits 0.47-3.31). The value of nicotine chewing gum, if any, can be quite small when it is used in general practice.     

Nicotine nasal spray with nicotine patch for smoking cessation: randomised trial with six year follow up

ObjectiveTo evaluate the efficacy of using a nicotine patch for 5 months with a nicotine nasal spray for 1 year.DesignPlacebo controlled, double blind trial.SettingReykjavik health centre.Subjects237 smokers aged 22-66 years living in or around Reykjavik.InterventionsNicotine patch for 5 months with nicotine nasal spray for 1 year (n=118) or nicotine patch with placebo spray (n=119). Treatment with patches included 15 mg of nicotine for 3 months, 10 mg for the fourth month, and 5 mg for the fifth month, whereas nicotine in the nasal spray was available for up to 1 year. Both groups received supportive treatment.ResultsThe log rank test for 6 years (χ²=8.5, P=0.004) shows a significant association between abstinence from smoking and type of treatment. Sustained abstinence rates for the patch and nasal spray group and patch only group were 51% v 35% after 6 weeks (P=0.011 (χ²), 95% confidence interval 1.17% to 3.32%), 37% v 25% after 3 months (P=0.045, 1.01% to 3.08%), 31% v 16% after 6 months (P=0.005, 1.27% to 4.50%), 27% v 11% after 12 months (P=0.001, 1.50% to 6.14%), and 16% v 9% after 6 years (P=0.077, 0.93% to 4.72%).ConclusionsShort and long term abstinence rates show that the combination of using a nicotine patch for 5 months with a nicotine nasal spray for 1 year is a more effective method of stopping smoking than using a patch only. The low percentage of participants using the nasal spray at 1 year, and the few relapses during the second year, suggest that it is not cost effective to use a nasal spray for longer than 7 months after stopping a patch.

Key messages

• Combined methods of nicotine replacement therapy have a potential advantage over one method because of high levels of substitution
• Nicotine patches release nicotine slowly, but nicotine nasal spray delivers nicotine more rapidly, enabling the smoker to respond quickly to any smoking urges
• Treatment with a patch and nicotine nasal spray was significantly more effective than patch and placebo from day 15 after stopping smoking
• Using a patch for 5 months with a nicotine nasal spray for 1 year provides a more effective means of stopping smoking than using a patch only
• It is not cost effective to use a nicotine nasal spray for longer than 7 months after stopping a patch

     

The effectiveness of two smoking cessation programmes for use in general practice: a randomised clinical trial.

OBJECTIVE--To evaluate a structured, behavioural change, smoking cessation intervention designed for use within general practice. DESIGN--Randomised controlled clinical trial. SETTING--General practices in Newcastle, Australia. PATIENTS--311 Patients identified as smokers by a screening question were enrolled in the study. Of these, 101 were assigned to a structured behavioural change programme, 104 to a simple advice programme adapted from previous research, and 106 to a control group. No significant differences were found between groups for demographic and smoking related variables before the study. INTERVENTIONS--Patients in the simple advice group received a brief statement of advice from the general practitioner as well as three pamphlets; those in the structured intervention group were given strategies which included attitude and behavioural change programmes as well as techniques to aid compliance. The amount of smoking in all groups was assessed by self reports with validation by measurement of salivary cotinine concentrations. MAIN OUTCOME MEASURE--Significant increase in cessation rates. CONCLUSIONS--Significant differences between controls and the structured behavioural change group were found at the one month follow up, but only for self reported abstinence. The simple advice programme did not produce any significant differences over the control group. General practitioner evaluation of the structured programme highlighted difficulties in relation to the duration of the intervention. Overall the structured programme in its present form did not appear to be an effective programme for use within general practice.     

District programme to reduce smoking: effect of clinic supported brief intervention by general practitioners.

By encouraging and supporting general practitioners to undertake brief intervention on a routine basis smokers'' clinics could reach many more smokers than are willing to attend for intensive treatment. In a study with 101 general practitioners from 27 practices 4445 cigarette smokers received brief intervention with the support of a smokers'' clinic, brief intervention without such support, or the general practitioners'' usual care. At one year follow up the numbers of smokers who reported that they were no longer smoking cigarettes were 51 (13%), 63 (9%), and 263 (8%), respectively (p less than 0.005). After an adjustment was made for those cases not validated by urine cotinine concentrations the respective success rates were 8%, 5%, and 5%. Use of nicotine chewing gum was associated with higher self reported success rates. General practitioners providing supported brief intervention encouraged not only more smokers to use the gum but also more effective use; gum users in this group reported a success rate of 27% at one year. Compliance by the general practitioners in recording smoking state averaged 45%, and significantly higher success rates were reported by patients whose smoking state had been recorded. Brief intervention by general practitioners with the support of a smokers'' clinic thus significantly enhanced success rates based on self reports. Better results might be obtained if general practitioners'' compliance with the procedure could be improved and if they encouraged more of their patients to try nicotine gum. Collaboration of this kind between a smokers'' clinic and local general practitioners could deliver effective help to many more smokers than are likely to be affected if the two continue to work separately.     

Prospective study of factors predicting outcome of transdermal nicotine treatment in smoking cessation.

OBJECTIVE--To assess the factors associated with cessation of smoking with transdermal nicotine and brief behavioural counselling. DESIGN--Interviews, treatment, and follow up for 26 weeks. SUBJECTS--1481 subjects recruited by mass media publicity who smoked > or = 15 cigarettes a day and were motivated to stop smoking. INTERVENTIONS--Twelve weeks'' treatment with transdermal nicotine and brief behavioural counselling at monthly visits. MAIN OUTCOME MEASURE--Sustained smoking cessation for the 28 days before the visit at week 26 verified by expired carbon monoxide concentrations. The logistic regression analysis included all subjects. RESULTS--Most subjects were dependent on nicotine, and the mean (SD) number of cigarettes smoked a day was 32 (12). Overall, 316/1481 subjects (21.3%) stopped smoking. Factors associated with stopping were being male (adjusted odds ratio 2.0; 95% confidence interval 1.5 to 2.7), age > or = 40 years (1.5; 1.1 to 2.0), living with a spouse or partner (1.5; 1.1 to 2.1), motivation ("want to quit" 1.7; 1.2 to 2.3), and concern about weight gain (1.7; 1.3 to 2.2). Negative associations were smoking marijuana (0.4; 0.2 to 0.8) and the presence of other smokers in the household (0.8; 0.6 to 0.9). Almost all subjects who smoked three or more cigarettes in the first four weeks of treatment resumed smoking in the long term (525/547, 96%). CONCLUSIONS--Age, sex, marital status (living with a spouse or partner), motivation, concern about weight gain, recent marijuana smoking, and other smokers in the household were baseline factors associated with differences in outcome of smoking cessation attempts. Smoking three or more cigarettes in the first few weeks after stopping strongly predicted long term relapse.     

How effective is nicotine replacement therapy in helping people to stop smoking?

OBJECTIVE--To assess the efficacy of nicotine replacement therapy in helping people to stop smoking. DESIGN--Analysis of the results of 28 randomised trials of nicotine 2 mg chewing gum, six trials of nicotine 4 mg chewing gum, and six trials of nicotine transdermal patch. SUBJECTS AND SETTING--Subjects were self referred (responding to advertisements or attending anti-smoking clinics) in 20 trials and invited (general practice or hospital patients) in 20. Therapists in self referred trials were generally experienced in helping people stop smoking but not in invited trials. MAIN OUTCOME MEASURE--Efficacy was defined as difference in percentages of treated and control subjects who had stopped smoking at one year. RESULTS--Efficacy was highly significant (P < 0.001) for both gum and patch. Nicotine 2 mg chewing gum had an overall efficacy of 6% (95% confidence interval 4% to 8%), greater in self referred subjects than in invited subjects (11% v 3%). Efficacy depended on the extent of dependence on nicotine as assessed by a simple questionnaire; it was 16% (7% to 25%) in "high dependence" smokers, but in "low dependence" smokers there was no significant effect. The 4 mg gum was effective in about one third of "high dependence" smokers. The efficacy of the nicotine patch (9% (6% to 13%) overall) was less strongly related to nicotine dependence, perhaps because the patch cannot deliver a bolus of nicotine to satisfy craving. CONCLUSIONS--Both gum and patch are effective aids to help nicotine dependent smokers who seek help in stopping. Among the most highly nicotine dependent smokers (those craving a cigarette on waking) the 4 mg gum is the most effective form of replacement therapy; it could enable one third to stop. In less highly dependent smokers the different preparations are comparable in their efficacy but the patch offers greater convenience and minimal need for instruction in its use. Overall, nicotine replacement therapy could enable about 15% of smokers who seek help in stopping smoking to give up the habit.     

Trial protocol and preliminary results for a cluster randomised trial of behavioural support versus brief advice for smoking cessation in adolescents

Background

Many young people report they want to stop smoking and have tried to do so, but most of their quit attempts fail. For adult smokers, there is strong evidence that group behavioural support enhances quit rates. However, it is uncertain whether group behavioural support enhances abstinence in young smokers trying to quit.

Findings

A cluster randomised trial for young people trying to stop smoking to compare the efficacy of a school-based 9 week intensive group behavioural support course versus a school-based 7 week brief advice only course. Participants were assessed for evidence of tobacco addiction and nicotine replacement therapy (NRT) was used if it was deemed appropriate by the therapist. Both types of course aimed to recruit approximately one hundred participants from approximately ten schools.The primary outcome was successful quitting at 4 weeks after quit day judged according to the Russell standard. Had the trial been completed, abstinence at 6 months after quit day and the relationships between successful quit attempts and 1) psychological assessments of dependence prior to quitting 2) salivary cotinine concentration prior to quitting and 3) sociodemographic characteristics would also have been assessed. The proportion of participants who stopped smoking in each arm of the trial were compared using Chi square tests.The trial was stopped shortly after it had started because funding to support the therapists running the stop smoking group behavioural support programme was withdrawn. Only three stop smoking courses were completed (two group support courses and one brief advice pharmacotherapy course). Seventeen participants in total entered the trial. At the end of the courses, one participant (10%) attending the group support programme had stopped smoking and no participant attending the brief advice programme had stopped smoking.

Discussion

The trial was stopped so we were unable to determine whether group support helped more young people to stop smoking than brief advice. Engagement and recruitment of participants proved much more difficult than had been anticipated. Fifteen of the seventeen participants reported that quitting smoking was either pretty important or very important to them. Thus, the stop smoking success rate could, nevertheless, be considered disappointing.

Trial registration

Current Controlled Trials ISRCTN25181936

     

Nortriptyline plus nicotine replacement versus placebo plus nicotine replacement for smoking cessation: pragmatic randomised controlled trial

Objective To test the efficacy of nortriptyline plus nicotine replacement therapy compared with placebo plus nicotine replacement therapy for smoking cessation.Design Pragmatic randomised controlled trial.Setting National Health Service stop smoking service clinics.Participants 901 people trying to stop smoking.Interventions Participants chose their nicotine replacement product, including combinations of nicotine replacement therapy, and received behavioural support. Nortriptyline was started one to two weeks before quit day, with the dose increased from 25 mg to 75 mg daily for eight weeks and reduced if not tolerated.Main outcome measures Primary outcome was prolonged confirmed abstinence at six months. Secondary outcomes were prolonged abstinence at 12 months, drug use, severity of side effects, nicotine withdrawal symptoms, and urges to smoke.Results 72 of 445 (16%) people using nortriptyline and 55 of 456 (12%) using placebo achieved prolonged abstinence at six months (relative risk 1.34, 95% confidence interval 0.97 to 1.86). At 12 months the corresponding values were 49 (11%) for nortriptyline and 40 (9%) for placebo (1.26, 0.84 to 1.87). 337 (79%) people in the nortriptyline arm and 325 (75%) in the placebo arm were taking combination treatment on quit day, median 75 mg per day in both groups. More people in the nortriptyline arm than in the placebo arm took lower doses. The nortriptyline arm had noticeably higher severity ratings for dry mouth and constipation than the placebo arm, with slightly higher ratings for sweating and feeling shaky. Both groups had similar urges to smoke, but nortriptyline reduced depression and anxiety. Overall, withdrawal symptom scores did not differ.Conclusions Nortriptyline and nicotine replacement therapy are both effective for smoking cessation but the effect of the combination is less than either alone and evidence is lacking that combination treatment is more effective than either alone.Trial registration Current Controlled Trials ISRCTN57852484.     

Nicotine chewing gum in general practice: effect of follow up appointments.

Two hundred smokers who were judged by their general practitioner to be motivated to stop smoking were allocated to one of two groups. All were offered an initial appointment at which they were advised to stop smoking and offered nicotine gum. One group then received no further appointments. The other was offered four further appointments over three months. Both groups were followed up at six and 12 months. At one year follow up 15.5% overall had stopped smoking, 14% in the low and 17% in the high contact group. This is better than most results so far reported for nicotine chewing gum in general practice, suggesting that general practitioners can use it to good effect. We compare this result with others achieved in general practice.     

Controlled trial of three different antismoking interventions in general practice.

Of 6052 adult patients who consulted their doctors in six Oxfordshire general practices between October 1980 and February 1981, 2110 (35%) were smokers. The smokers were allocated to one of four study groups--a control (non-intervention) group; a group that received verbal and written antismoking advice from the general practitioner; a group that received this advice and also a demonstration of exhaled carbon monoxide; and a group that received the advice plus the offer of further help from a health visitor. After one year 72% of smokers replied to a postal follow up questionnaire: 11% of the control group claimed to have stopped smoking compared with 15% in the group that received advice alone, 17% in the exhaled carbon monoxide group, and 13% in the health visitor group. Validation of these findings by assays of urinary concentrations of cotinine showed that between 24% and 40% of subjects may have misreported their smoking habits, but there was no indication that the rate of misreporting was higher in the intervention groups than in the control group. Giving advice routinely against smoking has a useful effect, and showing an immediate, personal, and potentially harmful consequence of smoking using a CO-oximeter may improve this, particularly in lower socioeconomic groups.     

Lack of Associations of CHRNA5-A3-B4 Genetic Variants with Smoking Cessation Treatment Outcomes in Caucasian Smokers despite Associations with Baseline Smoking

CHRNA5-A3-B4 variants, rs16969968, rs588765 and rs578776, are consistently associated with tobacco consumption among smokers, but the association with smoking cessation is less consistent. Among the studies that reported significant associations with cessation, the effects were observed in smokers treated with placebo treatment in some studies and conversely in those receiving active pharmacological therapy (bupropion and nicotine replacement therapies) in others. Thus, it remains unclear whether CHRNA5-A3-B4 is a useful marker for optimizing smoking cessation. Using data from 654 Caucasian smokers treated with placebo, nicotine patch or varenicline, we investigated whether CHRNA5-A3-B4 variants were associated with smoking cessation outcomes, and whether there were significant genotype-by-treatment or haplotype-by-treatment interactions. We observed no significant associations between CHRNA5-A3-B4 variants and smoking cessation, despite replicating previous associations with baseline tobacco consumption. At end of treatment the effect size on smoking cessation in the placebo, patch and varenicline groups for rs16969968 [GG vs. GA+AA] was OR = 0.66 (P = 0.23), OR = 1.01 (P = 0.99), and OR = 1.30 (P = 0.36) respectively, of rs588765 [CC vs. CT+TT] was OR = 0.96 (P = 0.90), OR = 0.84 (P = 0.58), and OR = 0.74 (P = 0.29) respectively, and for rs578776 [GG vs. GA+AA] on smoking cessation was OR = 1.02 (P = 0.95), OR = 0.75 (P = 0.35), and OR = 1.20 (P = 0.51) respectively. Furthermore, we observed no associations with cessation using the CHRNA5-A3-B4 haplotype (constructed using rs16969968 and rs588765), nor did we observe any significant genotype-by-treatment interactions, with or without adjusting for the rate of nicotine metabolism (all P>0.05). We also observed no significant genetic associations with 6 month or 12 month smoking abstinence. In conclusion, we found no association between CHRNA5-A3-B4 variants and smoking cessation rates in this clinical trial; however, as expected, significant associations with baseline tobacco consumption were replicated. Our data suggest that CHRNA5-A3-B4 gene variants do not exhibit a robust association with smoking cessation and are unlikely to be useful for clinically optimizing smoking cessation pharmacotherapy for Caucasian smokers.     

Open randomised trial of intermittent very low energy diet together with nicotine gum for stopping smoking in women who gained weight in previous attempts to quit

ObjectiveTo determine whether attempts to prevent weight gain will increase success rates for stopping smoking.Design16 week, open, randomised study with 1 year follow up.SettingObesity unit.Subjects287 female smokers who had quit smoking before but started again because of weight concerns.InterventionCombination of a standard smoking cessation programme with nicotine gum and a behavioural weight control programme including a very low energy diet. A control group was treated with the identical programme but without the diet.ResultsAfter 16 weeks, 68/137 (50%) women had stopped smoking in the diet group versus 53/150 (35%) in the control group (P=0.01). Among these women, weight fell by mean 2.1 (95% confidence interval 2.9 to 1.3) kg in the diet group but increased by 1.6 (0.9 to 2.3) kg in the control group (P<0.001). After 1 year the success rates in the diet and control groups were 38/137 (28%) and 24/150 (16%) respectively (P<0.05), but there was no statistical difference in weight gain.ConclusionsCombining the smoking cessation programme with an intervention to control weight helped women to stop smoking and control weight.     

Comparison of four methods of smoking withdrawal in patients with smoking related diseases. Report by a subcommittee of the Research Committee of the British Thoracic Society.

Four methods of smoking withdrawal were compared in patients with smoking related diseases attending a hospital or chest clinic. Reinforcing verbal advice with a booklet or with a booklet together with nicotine or placebo chewing gum did not result in greater success than verbal advice alone. Roughly a quarter of those patients who denied smoking had carboxyhaemoglobin and plasma thiocyanate concentrations typical of smokers. At the end of a year 150 out of 1550 patients (9.7%) had successfully stopped smoking.     

Is telephone counselling a useful addition to physician advice and nicotine replacement therapy in helping patients to stop smoking? A randomized controlled trial

BACKGROUND: The authors evaluated the incremental efficacy of telephone counselling by a nurse in addition to physician advice and nicotine replacement therapy in helping patients to stop smoking. METHODS: The trial was conducted at the University of Ottawa Heart Institute. A total of 396 volunteers who smoked 15 or more cigarettes daily were randomly assigned to either of 2 groups: usual care (control group) and usual care plus telephone counselling (intervention group); the groups were stratified by sex and degree of nicotine dependence. Usual care involved the receipt of physician advice on 3 occasions, self-help materials and 12 weeks of nicotine replacement therapy. Telephone counselling was provided by a nurse at 2, 6 and 13 weeks after the target quit date. Point-prevalent quit rates were determined at 52 weeks after the target quit date. RESULTS: The point-prevalent quit rates at 52 weeks did not differ significantly between the control and intervention groups (24.1% v. 23.4% respectively). The quit rates did not differ significantly at the secondary measurement points of 4, 12 and 26 weeks. INTERPRETATION: Brief physician assistance, along with nicotine replacement therapy, can help well-motivated smokers to quit. Three additional sessions of telephone counselling by a nurse were ineffective in increasing quit rates. This form of assistance may be useful in the absence of physician advice or when self-selected by patients.     

Lidocaine patch (5%) is no more potent than placebo in treating chronic back pain when tested in a randomised double blind placebo controlled brain imaging study

ABSTRACT: The 5% Lidocaine patch is used for treating chronic neuropathic pain conditions such as chronic back pain (CBP), diabetic neuropathy and complex regional pain syndrome, but is effective in a variable proportion of patients. Our lab has reported that this treatment reduces CBP intensity and associated brain activations when tested in an open labelled preliminary study. Notably, effectiveness of the 5% Lidocaine patch has not been tested against placebo for treating CBP. In this study, effectiveness of the 5% Lidocaine patch was compared with placebo in 30 CBP patients in a randomised double-blind study where 15 patients received 5% Lidocaine patches and the remaining patients received placebo patches. Functional MRI was used to identify brain activity for fluctuations of spontaneous pain, at baseline and at two time points after start of treatment (6 hours and 2 weeks). There was no significant difference between the treatment groups in either pain intensity, sensory and affective qualities of pain or in pain related brain activation at any time point. However, 50% patients in both the Lidocaine and placebo arms reported a greater than 50% decrease in pain suggesting a marked placebo effect. When tested against an untreated CBP group at similar time points, the patch treated subjects showed significantly greater decrease in pain compared to the untreated group (n=15). These findings suggest that although the 5% Lidocaine is not better than placebo in its effectiveness for treating pain, the patch itself induces a potent placebo effect in a significant proportion of CBP patients.     

Time and dose effect of transdermal nicotine on endothelial function

Nicotine patches are available as an over-the-counter medication for aid in smoking cessation. This study was designed to determine how nicotine patch therapy over time and dose ranges used in smoking cessation programs in humans affects endothelium-dependent relaxations. Dogs were treated with nicotine patches (11, 22, or 44 mg/day) for 2 and 5 wk. Circulating nicotine and oxidized products of nitric oxide (NOx) were measured. Coronary arteries were prepared for measurement of isometric force and aortic endothelial cells were prepared for measurement of mRNA or NO synthase (NOS) activity. Circulating nicotine increased with increasing concentrations of nicotine patches. After 5 wk of treatment with 22 mg/day patches, circulating NOx was reduced but NOS activity was increased. NOS mRNA was similar among groups. Only after 5 wk of treatment with 22 mg/day patches were endothelium-dependent relaxations reduced to alpha(2)-adrenergic agonists, ADP, and the calcium ionophore A-23187. These results suggest a time and biphasic dose effect of nicotine treatment on endothelium-dependent responses that may be related to bioavailability of NO. This complex relationship of duration and dose of nicotine treatment may explain, in part, discrepancies in effects of nicotine on endothelium-dependent responses.     

Weight gain and cardiovascular risk factors during smoking cessation with bupropion or nicotine.

Weight gain is frequent after smoking cessation, and may limit patient's will to quit and long-term success. Nicotine and bupropion are effective drugs for smoking withdrawal. However, their influence on weight gain, insulin resistance and other cardiovascular risk factors, as well as possible differences in obese and lean subjects, have not been fully evaluated. We randomised 25 lean and 25 obese smokers to receive either bupropion or nicotine patches. Clinical evaluation and lipid profile were performed at baseline and after treatment. Insulin resistance was also assessed at the end. Weight, BMI, waist-to-hip ratio, and diastolic blood pressure increased (p < 0.005), whereas lipid profile improved (p < 0.001) after smoking cessation independently of obesity at baseline or drug used. Obese patients had higher insulin resistance at the end (p < 0.05) regardless of drug used. Weight gain was inversely related to age (beta= - 0.125, R = 0.38, p = 0.046), and insulin resistance was related to obesity at baseline (beta = 0.85, R = 0.46, p = 0.02). In conclusion, weight gain after smoking cessation is not dependent on obesity or drug taken. A beneficial lipid profile is achieved after quitting smoking with either bupropion or nicotine patch in both obese and lean subjects.     

Metabolic effects of cigarette smoking.

The inverse relationship between cigarette smoking and body weight, a potent obstacle to stopping smoking, may be due in part to effects of smoking on increasing whole body metabolism. Studies examining chronic and acute metabolic effects of smoking, as well as its constituent nicotine, are reviewed. Evidence suggests the absence of a chronic effect; most studies indicate that smokers and nonsmokers have similar resting metabolic rates (RMR) and that RMR declines very little after smoking cessation. Although an acute effect due to smoking is apparent, its magnitude is inconsistent across studies, possibly because of variability in smoke exposure or nicotine intake. In smokers at rest, the acute effect of smoking (and nicotine intake) appears to be significant but small (less than 10% of RMR) and transient (less than or equal to 30 min). However, the specific situations in which smokers tend to smoke may mediate the magnitude of this effect, inasmuch as smoking during casual physical activity may enhance it while smoking after eating may reduce it. Sympathoadrenal activation by nicotine appears to be primarily responsible for the metabolic effect of smoking, but possible contributions from nonnicotine constituents of tobacco smoke and behavioral effects of inhaling may also be important. Improved understanding of these metabolic effects may lead to better prediction and control of weight gain after smoking cessation, thus increasing the likelihood of maintaining abstinence.     

Analysis of Factors That Determine Weight Gain during Smoking Cessation Therapy

Cigarette smokers are generally known to gain weight after quitting smoking, and such weight gain is thought to contribute to the worsening of glucose tolerance. While smoking cessation therapy such as nicotine replacement is useful to minimize post-cessation weight gain, substantial gain occurs even during the therapy. The purpose of the present study was to identify factors associated with weight gain during smoking cessation therapy. We evaluated 186 patients(132 males and 54 females)who visited our outpatient clinic for smoking cessation, and successfully achieved smoking abstinence. We performed gender-adjusted regression analysis for the rate of BMI increase from the beginning of cessation to 3 months after initiation. Furthermore, we performed multivariate analysis to investigate factors that determine the BMI increase after smoking cessation. The mean BMI significantly (p<0.0001) increased from 23.5±3.6 kg/m² at the initial consultation to 23.9±3.8 kg/m² at 3 months after the start of therapy. There was no significant difference in the extent of BMI increase between nicotine patch and varenicline therapy groups. Factors significantly correlated with the %BMI increase at 3 months after the start of therapy were triglyceride (p = 0.0006, βa = 0.260), high-density lipoprotein cholesterol (p = 0.0386, βa = −0.168), daily cigarette consumption (p = 0.0385, βa = 0.154), and the Fagerström Test for Nicotine Dependence (FTND) score (p = 0.0060, βa = 0.203). Stepwise multivariate analysis demonstrated that triglyceride and the FTND score were the factors determining the post-cessation BMI increase and that the FTND score was the strongest one. The present study demonstrated that smokers with a high FTND score are more likely to gain weight during smoking cessation therapy. Thus, smokers with a high nicotine dependency may require intervention against weight gain in the cessation clinic.