Occupational histories in neuropathologically confirmed multiple system atrophy.

Abstract

Purpose: This study examined occupational histories in multiple system atrophy to identify environmental associations of potential relevance to disease causation.

Methods: A total of 270 neuropathologically confirmed cases of multiple system atrophy obtained from the Mayo Clinic Brain Bank for neurodegenerative disorders in Jacksonville, Florida, were included in this case-control study. Demographic and disease information was collected from medical records. Information regarding occupational history was collected retrospectively from medical records and published obituaries. Proportions of employment by occupational sector were compared with US census data.

Results: When comparing patients with US census data, significant differences were identified for education (15.2% versus 2.3%, P < 0.001), administration (14.8% versus 4.1%, P < 0.001), clerical (10.7% versus 5.5%, P = 0.001), petroleum industry (8.9% versus 5.6%, P = 0.024), metal industry (7.8% versus 3.0%, P < 0.001), electrical engineers and electricians (5.6% versus 0.4%, P < 0.001), civil or mechanical engineering (4.4% versus 0.2%, P < 0.001), real estate (4.4% versus 0.7%, P < 0.001), information technology (4.1% versus 1.8%, P = 0.011), woodworking (3.0% versus 0.03%, P < 0.001), writing or publishing (2.6% versus 0.3%, P < 0.001), law (2.2% versus 0.4%, P = 0.001), hairdressing (0.7% versus 0.1%, P = 0.03), and social work (0.7% versus 0.1%, P = 0.03).

Conclusions: The listed occupational categories were significantly overrepresented in our series of patients with multiple system atrophy as compared with population data. We hypothesize that these occupational associations may signify environmental exposures, increasing the disease risk in genetically susceptible individuals. We cannot exclude a potential selection bias in patients willing to donate their brains to an academic center to contribute to scientific knowledge.