Medical costs of smoking in the United States: estimates, their validity, and their-implications

Objective-To compare estimates of the medical costs of smoking in the Unite d States and to consider their relevance to assessing the costs of smoking in developing countries and the net economic burden of smoking. Data sources-A Medline search through early 1999 using keywords "smoking" a nd "cost", with review of article reference lists. Study selection-Peer-reviewed papers examining medical costs in a single ye ar, covering the non-institutionalised American population. Data extraction-Methods underlying study estimates were identified, describ ed, and compared with attributable expenditure methodology in the literatur e dealing with costs of illness. Differences ins methods were associated wi th implied differences in findings. Data synthesis-With one exception, the studies find the annual medical cost s of smoking to constitute approximately 6-8% of American personal health e xpenditures. The exception, a recent study, found much larger attributable expenditures. The lower estimates may reflect the limitation of analysis to costs associated with the principal smoking-related diseases. The higher e stimate derives from analysis of smoking-attributable differences in all me dical costs. However, the finding from the most recent study, also consider ing all medical costs, fell in the 6-8% range. Conclusions-The medical costs of smoking in the United States equal, and ma y well exceed, the commonly referenced figure of 6-8%. This literature has direct methodological relevance to developing countries interested in asses sing the magnitude of their current cost-of-smoking burden and their future burdens, with differences in tobacco use histories and the availability of chronic disease treatment affecting country-specific estimates. The debate over the use of gross or net medical cost estimates is likely to intensify with the proliferation of lawsuits against the tobacco industry to recover expenditures on tobacco-produced disease.