Monday, April 16, 2012

New Study Shows that NRT is Dismally Effective for Lapsed Smokers

A new study published online ahead of print in the journal Addiction reports that nicotine replacement therapy (NRT) is effective for smoking cessation among smokers who have lapsed early in treatment. The study examined 6-week and 10-week cessation rates among smokers who lapsed during weeks 3-5 in clinical trials of nicotine patches. Compared to those using placebo, the NRT users were significantly more likely to be smoke-free at weeks 6 and 10.

According to the study: "Smokers who lapse during a cessation attempt are at particularly high risk of relapse, so interventions to help smokers recover from lapses are urgently needed. Two recent studies have suggested continuing to use nicotine patches following a lapse may be a beneficial relapse prevention strategy. However, to date no study that uses approved doses of nicotine patches under real-world conditions has tested this hypothesis. ... Using data from 509 subjects (240 active; 269 placebo) who lapsed during weeks 3–5 of treatment in a randomized, double-blind placebo-controlled trial of 21-mg nicotine patches, we examined whether active nicotine patch use improved the chances of recovering abstinence (7-day point-prevalence) at weeks 6 and 10. ... Active patch use (versus placebo) increased the likelihood of recovery from a lapse both at 6 weeks [8.3% versus 0.8%; relative risk (RR) = 11.0, P < 0.001] and at 10 weeks (9.6% versus 2.6%; RR = 3.7, P < 0.001)."

The study concludes: "Continuing treatment to aid smoking cessation with active patches promotes recovery from lapses. Smokers should be encouraged to persist with patch treatment if they lapse to smoking."

The Rest of the Story

I certainly don't contest the recommendation that NRT users who lapse early in treatment should not give up. They should continue using the patch to see if they can achieve smoking cessation. However, I do have a problem with the degree to which the paper considers NRT to be an effective strategy for smoking cessation.

Among those who lapsed early in treatment, the relative risk of abstinence at 10 weeks in the nicotine patch group compared to the placebo groups is 3.7. However, the absolute prevalence of abstinence at 10 weeks among the nicotine patch group is only 9.6%. This means that the overwhelming majority of smokers who lapse early in treatment are going to be unsuccessful, ultimately, in achieving smoking cessation. And this study is only measuring cessation at 10 weeks. Cessation at 6 months and at 1 year would be expected to be much lower than 9.6%.

Initially, I could not see how a treatment with a 90%+ failure rate could be called "effective." However, after reading the "fine print," a possible explanation appears:

"This study was supported by SmithKline Beecham Consumer Healthcare, now GlaxoSmithKline Consumer Healthcare (GSKCH), which markets nicotine replacement
medications for smoking cessation. GSKCH also supported the preparation of this manuscript. Through their work at Pinney Associates, the authors serve as consultants to GSKCH on an exclusive basis on matters related to smoking control and/or nicotine replacement medications. Dr Shiffman and Mr Gitchell also have a financial interest in a venture to develop new nicotine replacement medications."

This is a severe conflict of interest. The authors have a vested personal and professional financial interest in reporting the effectiveness of nicotine replacement therapy. Thus, it is perhaps not surprising that a treatment with a 90%+ failure rate at just 10 weeks is reported as being an effective strategy for this problem.

I think this is emblematic of a larger problem: the financial conflicts of interest created by tobacco control researchers taking money from Big Pharma for consultation or by getting into the business of developing medications themselves have created a situation where I do not believe the results of research on NRT treatment are being reported objectively or fairly. It is not appropriate, in my view, to tout a medication with a 90%+ failure rate as an "effective" approach to smoking cessation treatment. I think we can, and must do considerably better than that.

I would call NRT a dismal failure, not an effective strategy for smoking cessation. And I think the evidence base bears this out. This study itself supports my conclusion, as it demonstrates that the overwhelming majority of patients who lapse early in NRT treatment - greater than 90% of them - will ultimately fail in achieving smoking cessation, even just 10 weeks out from the start of treatment.

There is nothing wrong with a pharmaceutical company like GlaxoSmithKline funding a study like this, nor is there anything wrong with researchers taking money from GlaxoSmithKline to conduct a clinical trial of the effectiveness of NRT. However, I do think it is a major problem when investigators with personal financial interests in the drugs they are studying conduct and report the results of clinical trials designed to test the effectiveness of those drugs.

Generally, here at the Boston University Medical Center, we do not allow researchers with such financial conflicts of interest to participate as investigators in clinical trials. The Department of Medicine has an outright prohibition of such investigator involvement in clinical trials. These conflict of interest policies are designed to help prevent exactly the situation that has arisen with the NRT research literature. The rest of the story is that the reporting of these studies has the appearance of having lost scientific objectivity and a meaningful, real-world perspective because of these severe financial conflicts of interest.

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