To explore whether associations of potential risk factors for incidental Lewy Body Disease (iLBD) may be similar to Parkinson Disease (PD).
Design, Setting, and Patients
We identified brain-autopsied residents of Olmsted County, MN and immediate vicinity(1988–2004), age>60, without evidence of neurodegenerative disease or tremor, and evaluated by at least one physician within one year of death. Analysis for “incidental” Lewy pathology was done blinded to clinical abstraction.
Main Outcome Measures
Whether risk factors previously associated with PD in Olmsted County, MN are also associated with iLBD.
Of 235 subjects, 34 had iLBD(14.5%). The overall risk factor profiles for iLBD and PD were fairly similar between the two sets of OR estimates, with 11/16 ORs in the same direction. Prior Olmsted County studies documented 7 risk factors with statistically significant associations with PD; for two of these, the ORs for iLBD were in the same direction and statistically significant (physician, caffeine), whereas for three, they were in the same direction but not significant (education, head injury, number-of-children); they were in the opposite direction but not statistically significant for 2 (depression, anxiety). ILBD was not associated with various end-of-life conditions or causes-of-death, although they were slightly older and more likely cachectic.
Based on this exploratory study, iLBD and PD appear to have similar risk factor profiles. Thus, at least some cases of ILBD might represent preclinical PD, arrested PD or a partial syndrome due to a lesser burden of causative factors. ILBD is not explained by non-specific end-of-life brain insults.