title: Tobacco Stained Fingers and Its Association with Death and Hospital Admission: A Retrospective Cohort Study.
abstract: BACKGROUND
  Among smokers, the presence of tobacco stains on fingers has recently been associated with a high prevalence of tobacco related conditions and alcohol abuse.
  
  
  OBJECTIVE
  we aimed to explore tobacco stains as a marker of death and hospital readmission.
  
  
  METHODS
  Seventy-three smokers presenting tobacco-tar staining on their fingers and 70 control smokers were followed during a median of 5.5 years in a retrospective cohort study. We used the Kaplan-Meier survival analysis and the log-rank test to compare mortality and hospital readmission rates among smokers with and smokers without tobacco stains. Multivariable Cox models were used to adjust for confounding factors: age, gender, pack-year unit smoked, cancer, harmful alcohol use and diabetes. The number of hospital admissions was compared through a negative binomial regression and adjusted for the follow-up time, diabetes, and alcohol use.
  
  
  RESULTS
  Forty-three patients with tobacco-stained fingers died compared to 26 control smokers (HR 1.6; 95%CI: 1.0 to 2.7; p 0.048). The association was not statistically significant after adjustment. Patients with tobacco-stained fingers needed a readmission earlier than smokers without stains (HR 2.1; 95%CI: 1.4 to 3.1; p<0.001), and more often (incidence rate ratio (IRR) 1.6; 95%CI: 1.1 to 2.1). Associations between stains and the first hospital readmission (HR 1.6; 95%CI: 1.0 to 2.5), and number of readmissions (IRR 1.5; 95%CI: 1.1 to 2.1) persisted after adjustment for confounding factors.
  
  
  CONCLUSIONS
  Compared to other smokers, those presenting tobacco-stained fingers have a high unadjusted mortality rate and need early and frequent hospital readmission even when controlling for confounders.
authors.affiliation: Department of Internal Medicine, Hôpital neuchâtelois, 2300, La Chaux-de-Fonds, Switzerland; Department of Internal medicine geriatrics and rehabilitation, Geneva University Hospitals (HUG), Gabrielle-Perret-Gentil 4, CH-1205, Geneva, Switzerland.
authors.forename: Gregor
authors.initials: G
authors.lastname: John
authors.affiliation: Department of Internal Medicine, Hôpital neuchâtelois, 2300, La Chaux-de-Fonds, Switzerland.
authors.forename: Céline
authors.initials: C
authors.lastname: Louis
authors.affiliation: Department of Internal Medicine, Hôpital neuchâtelois, 2300, La Chaux-de-Fonds, Switzerland.
authors.forename: Amandine
authors.initials: A
authors.lastname: Berner
authors.affiliation: Department of Internal Medicine, Centre Hospitalier de Bienne, 2501, Bienne, Switzerland.
authors.forename: Daniel
authors.initials: D
authors.lastname: Genné
mesh_terms: D000368:Aged; D000428:Alcohol Drinking / Q000453:epidemiology; D004396:Coloring Agents / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010359:Patient Readmission / Q000706:statistics & numerical data*; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D015996:Survival Rate; D013557:Switzerland / Q000453:epidemiology; D013997:Time Factors; D014029:Tobacco Use Disorder / Q000150:complications / Q000401:mortality*
chemical_list: D004396:Coloring Agents