You will be provided with the titles and abstracts of a collection of medical RCT reports studying a clinical question -- for instance, the efficacy of an intervention on some medical outcome. Please write a few sentences synthesizing the findings of these reports, which could serve as a conclusion section for a systematic review article. Your response should not include any other text. The RCT reports are below.



Title 1:
Smoking cessation, clonidine, and vulnerability to nicotine among dependent smokers.
Abstract 1:
This study examines the efficacy of clonidine in smoking cessation and the influence of gender, history of major depression, and measures of nicotine dependence.
                The study was designed as a 10-week double-blind randomized comparison stratified for gender and major depression. Three hundred subjects who smoked cigarettes heavily were enrolled in the study. Abstinence from smoking was evaluated by self-report and verified by serum cotinine levels.
                Gender, major depression recurrent type, and measures of nicotine addiction were risk factors for treatment failure. There was no clonidine effect in men, but there was a modest effect in women (odds ratio, 2.01; 95% confidence interval, 1.00 to 4.10) that was most pronounced (odds ratio, 8.5; 95% confidence interval, 1.67 to 43.62) among women with the highest risks.
                Measures of addiction and major depression predict treatment failure. Together they are stronger predictors of outcome than drug. Clonidine is a limited aid in cessation, and drug effects come primarily from women at high risk for treatment failure. An increased risk for psychiatric complications after smoking cessation was apparent among smokers with histories of major depression, particularly bipolar disease.


Title 2:
Randomized, controlled trial of transdermal clonidine for smoking cessation.
Abstract 2:
To determine the efficacy and safety of clonidine versus placebo in smoking cessation.
                Single-center, randomized, double-blind, parallel-design comparison of transdermal clonidine with behavior modification, transdermal clonidine without behavior modification, placebo with behavior modification, and placebo without behavior modification.
                Outpatient, university-based ambulatory care facility.
                One hundred fifty generally healthy, highly nicotine-dependent cigarette smokers.
                Clonidine was given as the transdermal patch initiated 72 hours prior to smoking-cessation attempts and continued for six weeks thereafter. Clonidine was given at a dose of 0.2 mg/d for patients weighing more than 150 pounds (> 67.5 kg) and at a dose of 0.1 mg/d for patients weighing less than 150 pounds (< 67.5 kg). Behavior modification consisted of a total of 12 one-hour structured group training sessions. Patients not receiving behavior modification received printed material, which included the "Help Quit Kit" and the "I Quit Kit" from the American Cancer Society.
                Smoking-cessation rates were assessed at 6, 12, 24, and 52 weeks of follow-up. In addition, adverse reactions to clonidine or placebo were evaluated.
                Clonidine with behavior modification was statistically superior to the other three treatment groups but only at 6 weeks of follow-up. There were no differences in smoking-cessation rates among any of the treatment groups at any other follow-up intervals. Patients receiving behavior modification, regardless of whether they received clonidine, had better quit rates than patients not receiving behavior modification at all follow-up times except 52 weeks. Women receiving clonidine had significantly better quit rates than men receiving clonidine at all follow-up visits. Clonidine was associated with a significantly higher incidence of adverse effects than placebo (52 vs. 11 percent). However, the number of smokers withdrawing from the study was not greater with clonidine compared with placebo (9 vs. 7 percent, respectively).
                Clonidine is probably not effective as a pharmacologic adjunct to behavior modification in smoking cessation. It may have a potential role in women smokers who do not respond to or cannot tolerate more traditional smoking-cessation therapies.


Title 3:
Heavy smokers, smoking cessation, and clonidine. Results of a double-blind, randomized trial.
Abstract 3:
Seventy-one heavy smokers who had failed in previous attempts to stop smoking participated in a randomized clinical trial to test the efficacy of clonidine as an aid in smoking cessation. The success rate in clonidine-treated subjects (verified by serum cotinine concentration) was more than twice that in the placebo-treated subjects. When the data were stratified by gender, a strong effect present in women was not apparent in men. After six months, cessation rates remained significantly higher among smokers treated with clonidine than those receiving placebo. The data also revealed an unexpectedly high prevalence (61%) of a history of major depression in this sample and a significant negative effect of such a history on cessation regardless of treatment. These findings, highly suggestive of an important role of clonidine in smoking cessation, warrant further studies to establish the long-term (greater than or equal to 12 months) efficacy of this drug and to replicate the association between nicotine dependence and depression.


Title 4:
Effect of clonidine on cigarette cessation and in the alleviation of withdrawal symptoms.
Abstract 4:
nan
Based on a small number of trials, in which there are potential sources of bias, clonidine is effective in promoting smoking cessation. Prominent side-effects limit the usefulness of clonidine for smoking cessation.