Biomedical subjects

S L Kenford

Publications and source records attributed to S L Kenford.

6 recordsLinked to original sources

PubMed1999

Gender differences in smoking cessation.

Gender differences in smoking quit rates are frequently reported and are the subject of much speculation. This study examined the generalizability of gender differences in abstinence across study sites, treatments, and time of relapse, as well as potential mediators and moderators of gender effects. Participants were smokers who participated in 3 randomized clinical trials of the nicotine patch (N = 632). Men had higher cessation rates than women at all follow-ups. The impact of gender on abstinence was unaffected by controlling for study site, treatment, or time of relapse. There was little evidence for mediation or moderation of this relation by any of a host of predictor variables. The magnitude and consistency of the gender differential, coupled with an inability to account for it, highlights a compelling need for additional research specifically aimed at elucidating the relation between gender and abstinence.

Administration, Cutaneous↗

PubMed1994

Predicting smoking cessation. Who will quit with and without the nicotine patch.

OBJECTIVE: To identify predictors of smoking cessation success or failure with and without transdermal nicotine patch treatment. DESIGN: Two independent randomized, double-blind, placebo-controlled studies using the nicotine patch assessing outcome at the end of treatment and at 6-month follow-up; each study used a different mode of adjuvant counseling. PATIENTS: Subjects were daily smokers (> or = 15 cigarettes per day), aged 21 to 65 years with expired air carbon monoxide levels of at least 10 ppm, and motivated to quit. Eighty-eight subjects participated in study 1, and 112 subjects participated in study 2. INTERVENTION: Study 1 consisted of 8 weeks of 22-mg nicotine patch therapy with intensive group counseling. Study 2 consisted of 4 weeks of 22-mg nicotine patch therapy and 2 weeks of 11-mg nicotine patch therapy with brief individual counseling. MAIN OUTCOME MEASURES: The prediction of smoking cessation (at end of treatment and after 6 months) based on pretreatment and intratreatment measures in smokers using active or placebo nicotine patches. RESULTS: Pretreatment markers, such as the Fagerstrom Tolerance Questionnaire score, number of cigarettes smoked per day, years smoked, expired air carbon monoxide level, or baseline blood nicotine and cotinine levels, showed no consistent relationship with successful smoking cessation across both studies. Of the intratreatment markers examined, withdrawal severity and nicotine replacement levels also were not consistently predictive of cessation success. However, any smoking during the second week of treatment was a consistent and powerful predictor of failure at the end of treatment and after 6 months. Among active nicotine patch patients who smoked at all during week 2 after quitting, 83% and 97% (studies 1 and 2, respectively) were smoking at 6-month follow-up. Conversely, abstinence during the second week of treatment predicted successful smoking cessation. Among active nicotine patch patients who were totally abstinent during week 2 after quitting, 46% and 41% (studies 1 and 2, respectively) were abstinent at 6-month follow-up. Of all nicotine patch patients in both studies who were smoking at 6-month follow-up, 74% began smoking during week 1 or 2. Among all placebo patch patients who were smoking at 6-month follow-up, 86% began smoking during week 1 or 2. CONCLUSIONS: Smoking status (abstinent or smoking) during the first 2 weeks of nicotine patch therapy, particularly week 2, was highly correlated with clinical outcome and can serve as a powerful predictor of smoking cessation. Early smoking behavior also predicted outcome among placebo patch users. Traditional measures of dependence are not consistently predictive of cessation success. Clinicians are advised to emphasize the importance of total abstinence after a quit attempt and to follow-up with patients within the first 2 weeks of quitting; smoking during this critical time should be assessed and treatment may be altered as appropriate.

Administration, Cutaneous↗

PubMed1994

Smoking outcome expectancies: factor structure, predictive validity, and discriminant validity.

Recent models of addiction posit that drug outcome expectancies are influential determinants of drug use. The current research examines the dimensional structure, predictive validity, and discriminant validity of expectancies for cigarette smoking in a prospective study. There was a good fit between the factor structure of the Smoking Consequences Questionnaire and the observed data. In addition, the internal consistency of each scale was satisfactory. Moreover, there was considerable evidence for the predictive and discriminant validity of expectancies. Expectancies of positive outcomes (positive reinforcement, negative reinforcement, and appetite-weight control) predicted withdrawal severity. Negative reinforcement expectancies and expectancies of negative consequences predicted cessation success. Predictive relations remained significant after controlling for related constructs: negative affect, stress, and dependence measures.

Adult↗

PubMed1994

Two studies of the clinical effectiveness of the nicotine patch with different counseling treatments.

OBJECTIVE: To assess the effectiveness of transdermal nicotine therapy for smoking cessation and suppression of withdrawal severity in conjunction with two different adjuvant counseling treatments. DESIGN: Two independent randomized placebo-controlled double-blind trials. SETTING: Smoking cessation clinic. SUBJECTS: Eighty-eight (study 1) and 112 (study 2) adult volunteers motivated to quit smoking. INTERVENTIONS: Eight weeks of 22-mg transdermal nicotine therapy with group counseling (study 1); 4 weeks of 22 mg followed by 2 weeks of 11-mg transdermal nicotine therapy with brief individual counseling (study 2). MAIN OUTCOME MEASURES: Modified point prevalence (7 consecutive days of nonsmoking) at the end of patch treatment and 6 months after treatment initiation was assessed by self-report and biochemically confirmed; survival analyses were also conducted for both studies to compare treatment efficacy. Also, we examined the impact of the nicotine patch on specific withdrawal symptoms (anger, anxiety, awakening, difficulty concentrating, depression, hunger, impatience, and craving). RESULTS: Transdermal nicotine treatment produced higher cessation rates at the end of treatment than did placebo with both adjuvant counseling interventions: 59 percent vs 40 percent (p < 0.05 in study 1) and 37 percent vs 20 percent (p < 0.05 in study 2), respectively. Smoking cessation efficacy was maintained 6 months after initiation of treatment: 34 percent vs 21 percent (p = 0.08 in study 1) and 18 percent vs 7 percent (p = 0.05 in study 2). Survival analyses also revealed significant group differences in efficacy in both studies. Nicotine patches also suppressed a variety of withdrawal symptoms, including craving in the first weeks after patients quit smoking. CONCLUSION: Transdermal nicotine effectively augments smoking cessation rates with two different types of counseling treatment. Overall, the nicotine patch approximately doubles the sustained rate of smoking cessation. Additionally, the nicotine patch provides relief from some tobacco withdrawal symptoms.

Administration, Cutaneous↗

PubMed1993

Prevalence of daily and experimental smoking among University of Wisconsin-Madison undergraduates, 1989-1993.

Limited information is available on smoking among college students. This study surveyed smoking prevalence and frequency among University of Wisconsin-Madison undergraduates aged 17 to 22 (n = 6,069) during the years 1989 through 1993. Sampling was conducted before and after the implementation of a smoke-free campus policy. Daily smoking remained constant across the 5 years at just under 10% of the sample; males showed a trend toward increased daily smoking (7.8% to 11.7%), while females showed a declining trend (10.2% to 8.4%). Additionally, 27% engaged in experimental smoking (smoking every few days, weeks, or months), resulting in a disturbing overall rate of tobacco use: about 37% of all students. These data indicate a need for more directed efforts to help university students overcome the threat of tobacco addiction.

Adolescent↗

PubMed1992

Tobacco dependence and the nicotine patch. Clinical guidelines for effective use.

OBJECTIVE: A comprehensive review of transdermal nicotine treatment for tobacco dependence, with recommendations derived from the research literature. DATA SOURCES: English-language clinical trials. STUDY SELECTION: Clinical trials using placebo-controlled, double-blind methodology (11 studies) with at least 6 months of follow-up after treatment (eight studies) and biochemical verification of smoking status. DATA SYNTHESIS: Nicotine patches produce end-of-treatment smoking cessation rates that range from 18% to 77%; these rates are about twice those of placebo-treated subjects. Nicotine patches produced 6-month abstinence rates of 22% to 42%, while placebo patches produced quit rates of 5% to 28%. Nicotine patches appear to reduce some, but not all, nicotine withdrawal symptoms. For instance, while the patch reduces craving for cigarettes and negative moods, it does not appear to reduce hunger or weight gain. The clinical trials literature suggests that proper adjuvant smoking cessation counseling is crucial in determining successful long-term outcome with the nicotine patch, and suggests that 6 to 8 weeks of patch therapy may be an adequate duration for most patients. CONCLUSIONS: Nicotine patches are an effective aid to tobacco dependence treatment. However, success rates vary greatly across research studies and may be influenced highly by the nature and intensity of adjuvant smoking cessation counseling. More research is needed to identify optimal duration, dosage, and individualization of patch therapy. The impact of nicotine patches (more than 5 million users with $1 billion in sales for 1992) also raises important ethical and public health issues.

Administration, Cutaneous↗