Outcomes Among People With Schizophrenia Participating in General-Population Smoking Cessation Treatment: An Observational Study.

OBJECTIVE: People with schizophrenia are much more likely than others to smoke tobacco, raising risks of disease and premature mortality. These individuals are also less likely to quit successfully after treatment, but the few existing clinical and observational studies have been limited by small sample sizes, and have generally considered specialized treatment approaches. In this analysis, we examine outcomes, service use, and potential explanatory variables in a large sample of people with schizophrenia treated in a general-population cessation program. METHOD: Our sample comprised 3,011 people with schizophrenia and 77,790 controls receiving free nicotine replacement therapy through 400 clinics and health centres. We analysed self-reported 7-day abstinence or reduction at 6-month follow-up, as well as the number of visits attended and self-reported difficulties in quitting. We adjusted for demographic, socioeconomic, and health variables, and used multiple imputation to address missing data. RESULTS: Abstinence was achieved by 16.2% (95% confidence interval [CI], 14.5% to 17.8%) of people with schizophrenia and 26.4% (95% CI, 26.0% to 26.7%) of others (absolute difference = 10.2%; 95% CI, 8.5% to 11.9%; P < 0.001). After adjustment, this difference was reduced to 7.3% (95% CI, 5.4% to 9.3%; P < 0.001). Reduction in use was reported by 11.8% (95% CI, 10.3% to 13.3%) and 12.5% (95% CI, 12.2% to 12.8%), respectively; this difference was nonsignificant after adjustment. People with schizophrenia attended more clinic visits (incidence rate ratio [IRR] = 1.15, 95% CI = 1.12% to 1.18%, P < 0.001) and reported more difficulties related to "being around other smokers" (odds ratio [OR] = 1.28; 95% CI, 1.11% to 1.47%; P = 0.001). CONCLUSION: There is abundant demand for tobacco cessation treatment in this population. Outcomes were substantially poorer for people with schizophrenia, and this difference was not explained by covariates. Cessation remained much better than for unaided quit attempts, however, and engagement was high, demonstrating that people with schizophrenia benefit from nonspecialized pharmacological treatment programs.

Adequacy of nicotine replacement and success quitting tobacco in clinical populations: An observational study.

BACKGROUND: Nicotine replacement therapy (NRT) for smoking cessation is an effective intervention that reduces urges to smoke by substituting a safer source of nicotine. NRT dosing is imprecise, however, and there is some evidence that patients and providers are reluctant to use the larger doses that may be appropriate for some people who smoke. In this analysis, we assess the relationship between cigarettes smoked and NRT prescribed, and between adequacy of nicotine replacement and cessation success. METHODS: We analyzed data from 84,667 patients and 492 clinics participating in a province-wide NRT-based smoking cessation program. We evaluated the association between cigarettes per day (CPD) and NRT dose using descriptive methods, and used mixed-effects logistic regression to identify associations between dose and outcome. We used fractional polynomials to fit non-linear associations and multiple imputation to address missing data. RESULTS: Prescribed NRT doses increased much less than proportionately with CPD, with a median for higher CPD levels of about 1 mg/CPD at baseline. Doses did not increase at subsequent visits for people who continued to smoke daily. Dose-response curves derived from our model showed that initial doses below about 2 mg/CPD/day were associated with poorer outcomes. CONCLUSIONS: Under-dosing of NRT, both at treatment initiation and subsequent clinical contacts, is likely to contribute to the poorer treatment outcomes seen among people who smoke heavily. Improved communication with providers and patients is probably needed to overcome reluctance to use larger doses.