Tobacco-stained fingers: a clue for smoking-related disease or harmful alcohol use? A case-control study.

Objective: Tobacco stain on fingers is frequent. However, there is scarce description of this clinical sign. We aimed to explore tobacco stain on fingers as a marker of tobacco-related disease independent of cumulative tobacco exposure, and to find behavioural and environmental characteristics associated with those stains.

Design: Case-control study.

Setting: A Swiss community hospital of 180 beds.

Participants: 49 adults presenting tobacco-tars staining on fingers were matched to 49 control smokers by age, gender, height and pack-year (PY).

Outcome Measures: Documented smoking-related carcinoma, ischaemic heart disease, peripheral arterial disease, stroke and chronic obstructive pulmonary disease (COPD), also determined by lung function, were compared between groups. Association between harmful alcohol use, mental disorders or unemployment and tar-staining was adjusted for smoking behaviour through conditional logistic regression.

Results: Overall cigarette-related disease was high in the case group (84%), and symptomatic peripheral arterial disease was more frequent compared to controls (OR 3.5, CI 95% 1.1 to 14.6). Smoking-related carcinoma, ischaemic heart disease, stroke and COPD were not statistically different for control smokers. Harmful alcohol use was strongly associated with stains and this association persists after adjustment for smoking unfiltered cigarettes, smoking more than one pack of cigarettes in a day and age at smoking onset (adjusted OR 4.6, CI 95% 1.2 to 17.2). Mental disorders and unemployment were not statistically significant.

Conclusions: Patients with tobacco-tar-stained fingers frequently have cigarette-related disease, however statistically not more than control smokers matched for PY, except for symptomatic peripheral arterial disease. This study suggests a link between stained fingers and addictive behaviour or concomitant high alcohol consumption.