Schizophrenia and Smoking: Weighing the Role of the Tobacco Industry
8 December 2007. The prevalence of cigarette smoking in the United States has declined precipitously over the past four decades to about 20 percent of the general adult population, half what it was when the Surgeon General released the landmark 1964 report on smoking and health (Centers for Disease Control and Prevention [CDC], 2007). However, cigarette smoking is twice as common among the mentally ill as in the general population (Lasser et al., 2000), which translates into $37 billion in annual sales for the tobacco industry. The prevalence of smoking among those diagnosed with schizophrenia is particularly striking, with some researchers proposing rates as high as 88 percent (Hughes et al., 1986).
A new report, published online November 5, 2007, in Schizophrenia Bulletin by Judith Prochaska and colleagues at the University of California, San Francisco, proposes that a concerted, multi-pronged effort by that industry has sustained the high rate of smoking among patients with schizophrenia, both by promoting their use of cigarettes and by discouraging smoking bans and smoking cessation programs in psychiatric hospitals.
Smoking is not hazardous to your health?
For their study, the UCSF team relied on word-searchable databases, such as the Legacy Tobacco Documents Library, of the nearly 40 million pages of internal tobacco industry documents that were made publicly available after a 1998 judgment against the industry by the State of Minnesota. Based on the information in documents retrieved by broad keyword searches (e.g., “psychosis”), the Prochaska group performed progressively restricted searches based on names of programs and individuals, dates, and reference numbers. The preliminary search yielded 280 documents, 130 of which were from the archive of the Council for Tobacco Research (CTR), an industry organization originally founded in the mid-1950s to fund research that could be used in public relations campaigns to counter the growing tide against cigarette smoking.
According to the UCSF team, the documents reveal that promotional tactics of the tobacco industry toward individuals with schizophrenia took two main forms. First, they funded research to corroborate the idea, largely based on anecdotal evidence, that individuals with schizophrenia have some psychosomatic or genetic profile that bestows resistance to tobacco-related diseases. They also backed studies of the hypothesis that the high rate of smoking among patients with schizophrenia represented a beneficial form of “self-medication,” presumably mediated by nicotinic acetylcholine receptors. Second, either directly or in collaboration with patient advocacy groups, the industry took steps to see that psychiatric patients had easy access to cigarettes and that smoking bans in psychiatric hospitals would either be lifted or substantially relaxed.
The authors found that as far back as the 1950s the industry was collecting correspondence and other material from medical journals proposing that patients with schizophrenia have low rates of cancer despite high rates of smoking. The CTR and other industry organizations funded studies—later discredited—asserting that patients with schizophrenia are less likely to develop cancer from smoking because they did not repress grief and other emotions as strongly as those in the general population.
Prochaska and colleagues cite a 1982 research grant proposal to the Canadian Tobacco Manufacturers’ Council (CTMC), wherein one investigator who planned to explore the self-medication hypothesis pointed out to the reviewers that positive findings would be a “significant bonus for the tobacco industry,” and indicated that patients who participated in the study would be paid in either cash or cigarettes. The Prochaska group found evidence that for both the disease-resistance and self-medication lines of inquiry, the industry denied funding to investigators whose grant requests entertained the possibility of negative findings, favoring researchers who approached these problems “from our point of view,” as Prochaska and colleagues quote an internal company memo on a scientist who depended on CTMC money.
The documents reveal that only a fraction of industry-funded studies discussed in researchers’ progress reports were eventually published in peer-reviewed journals, a disparity that the Prochaska team takes as evidence that a great deal of unfavorable data may have been suppressed, a pattern they say has been paralleled in the industry’s research programs on harmfulness of second-hand smoke.
Forty years behind
Recent studies have revealed that individuals with schizophrenia have a higher risk of developing diseases associated with cigarette smoking, including lung cancer (Lichtermann et al., 2001), cardiovascular disease (Goff et al., 2005), and respiratory problems (Himelhoch et al., 2004), though the possible confounding effects of poor diet, lack of exercise, and side effects of antipsychotic medications have not been fully sorted out (see related SRF news story).
Prochaska and colleagues suggest that the tobacco industry’s greatest damage to the health of patients with schizophrenia may be indirect: because the research enterprise has been skewed toward tobacco’s supposed harmlessness or beneficial effects, “astoundingly little” research has been published on smoking cessation among psychiatric patients. “Might it be,” the authors ask, “that the mentally ill are the largest remaining group of smokers, not because they need to smoke but rather because they are among the last to be treated?”—Peter Farley.
Prochaska JJ, Hall SM, Bero LA. Tobacco use among individuals with schizophrenia: what role has the tobacco industry played? Schizophr Bull. 2007 Nov 5 [Epub ahead of print]. Abstract.