Impact of environmental tobacco smoke on children with sickle cell disease.

BACKGROUND Parallels between the biological effects of exposure to environmental tobacco smoke (ETS) on nonsmokers and the pathophysiology of sickle cell disease (SCD) suggest that complications of SCD could be exacerbated by ETS exposure. OBJECTIVE To determine whether children with SCD who are exposed to ETS at home have more sickle cell crises than do those who live in nonsmoking households. DESIGN A retrospective cohort study in which ETS exposure was measured by using a survey of caretakers and patients. SETTING A university-based pediatric sickle cell center. PARTICIPANTS Fifty-two of 66 eligible children aged 2 to 18 years with SCD. OUTCOME MEASURES The number of sickle cell vaso-occlusive crises requiring hospitalization per patient during the 2-year study (inpatient sickle cell crises). Total hospital days and hospital costs were secondary outcome measures. RESULTS Patients exposed to ETS had more inpatient sickle cell crises than did unexposed patients (mean +/- SD, 3.7 +/- 5.7 vs 1.7 +/- 3.5; P =.02), and this association retained significance after adjustment for important covariates (risk ratio, 1.9; 95% confidence interval, 1.3-2.7). Hospital costs were greater in the exposed group than in the unexposed group (mean +/- SD, 21,671 US dollars +/- 41,809 US dollars vs 9705 US dollars +/- 19 146 US dollars; effect estimate, 11.4; 95% confidence interval, 1.0-129.5). CONCLUSIONS Children with SCD who are exposed to ETS have a higher risk of sickle cell crises requiring hospitalization than do those not exposed, independent of other factors known to increase the frequency of sickle cell crises. Decreasing the exposure of these children to ETS could reduce morbidity and may provide cost savings.