Research Reports - Head injury at early ages is associated with risk of Parkinson's disease
Parkinsonism Relat Disord. 2016 Feb;23:57-61. doi:
10.1016/j.parkreldis.2015.12.005. Epub 2015 Dec 19.
Taylor KM(1), Saint-Hilaire MH(2), Sudarsky L(3), Simon DK(4), Hersh B(5),
Sparrow D(6), Hu H(7), Weisskopf MG(8).
INTRODUCTION: The literature on the effect of head injuries on the risk of PD is
inconclusive. Some researchers have hypothesized that studies that have seen an
effect are simply capturing injury related to pre-clinical PD. However in animal
models brain inflammation, which can be initiated by head trauma, has been shown
to produce PD-like effects. Furthermore, animal studies have found that early
life inflammation in particular is of relevance for PD pathology.
METHODS: We conducted an unmatched case-control study of 379 neurologist
confirmed PD patients and 230 controls from the greater Boston, Massachusetts
area with questionnaire data on history of head injury and other covariates. We
used multivariable logistic regression to estimate adjusted odds ratios (OR) and
their corresponding 95% confidence intervals (CI) for PD.
RESULTS: When we excluded injuries that occurred less than 10 years prior to the
diagnosis of PD (in order to avoid reverse causation), we found an increased risk
of PD associated with a head injury that resulted in a loss of consciousness, but
it did not reach statistical significance (OR = 1.57; 95% CI = 0.89-2.80). We
found a significant (p = 0.04) effect of age at first head injury. For every 5
year earlier age at first head injury with loss of consciousness the OR for PD
was 1.37 (95% CI: 1.01-1.86).
CONCLUSION: Our results suggest that head injury in early life increases the risk