A case-control study of tobacco and alcohol consumption in Leber hereditary optic neuropathy

PURPOSE: To determine if tobacco or alcohol consumption is associated with vision loss among sibships harboring pathogenic mitochondrial mutations ass ociated with Leber hereditary optic neuropathy. METHODS: Retrospective case control study with questionnaires obtained from both affected and unaffected siblings from 80 sibships with Leber heredita ry optic neuropathy. Sibships harbored molecularly confirmed mitochondrial DNA mutations at nucleotide positions 11778 (63), 14484 (10), and 3460 (7). Exposure in affected individuals was calculated based on reported consumpt ion before vision loss. RESULTS: For male probands (67 sibships), the recurrence risk within a sibs hip was 10.3% (eight of 78) for males and 3.1% (three of 98) for females. F or female probands (13 sibships), the recurrence risk within a sibship was 17.6% (three of 17) for males and 0% (zero of 22) for females. Greater risk of vision loss was associated with male sex (odds ratio [OR] = 6.63; 95% c onfidence interval [CI] = 2.96 to 14.843 P = .00001) and harboring a 3460 o r 14484 in comparison with the 11778 mutation (OR = 2.071; 959% CI = 1.19 t o 3.58; P = .0095). No significant association of maximal intensity of smok ing or cumulative smoking, whether light or heavy, with vision loss was obs erved. Light (OR = 0.31; 95% CI = 0.17 to 0,56; P = .0001) and heavy alcoho l consumers (OR = 0.25; 95% CI = 0.11 to 0.58; P = .0011) were less likely to be affected than individuals who did not consume alcohol after adjusting for age, sex, and mutation. In a categorical analysis of sibships with the 3460 or 14484 mutation, no relationship of vision loss with tobacco or alc ohol consumption was observed. CONCLUSION: Unlike previous studies, the present study calculated exposure based on self-reported consumption of tobacco or alcohol before vision loss , No significant deleterious association between tobacco or alcohol consump tion and vision loss among individuals harboring Leber hereditary optic neu ropathy mutations was observed. Tobacco and alcohol do not appear to promot e vision loss in Leber hereditary optic neuropathy. (C) 2000 by Elsevier Sc ience Inc. All rights reserved.