Objective To compare macular choroidal thickness between cigarette smokers, those with a history of smoking, and nonsmokers in patients over 65 years of age with earlyatrophic age-related macular degeneration (AMD) and normals. Methods Prospective, consecutive, observational case series. Enhanced depth imaging spectral domain optical coherence tomography 12-line radial scans were performed and choroidal thickness manually quantified at 84 points in the central 3 mm of the macula. Data of normals, soft drusen alone, and soft drusen with additional features of early AMD were compared. A multivariate analysis of variance (MANOVA) model, controlling for age, was constructed to evaluate the effect of smoking history and AMD features on choroidal thickness. Results A history of smoking was significantly associated with a thinner choroid across all patients via logistic regression (P ¼ 0.004; O.R. ¼ 12.4). Mean macular choroidal thickness was thinner for smokers (148±63 mm) than for nonsmokers (181±65 mm) among all diagnosis categories (P ¼ 0.003). Subgroup analysis of patients with AMD features revealed a similar decreased choroidal thickness in smokers (121 ± 41 mm) compared with nonsmokers (146 ± 46 mm, P ¼ 0.006). Bivariate analysis revealed an association between increased pack-years of smoking and a thin choroid across all patients (Po0.001) and among patients with features of early AMD (Po0.001). Both the presence of features of macular degeneration (Po0.001) and a history of smoking (P ¼ 0.024) were associated with decreased choroidal thickness in a MANOVA model.
ConclusionChronic cigarette smoke exposure may be associated with decreased choroidal thickness. There may be an anatomic sequelae to chronic tobacco smoke exposure that underlies previously reported AMD risk.