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Factor XII Concentrations and Risk of Intracerebral Haemorrhage. A Prospective Case-Referent Study
Kristina Johansson1, Lars Johansson1, Torbjörn K Nilsson2
1Department of Public Health and Clinical Medicine, Skellefteå Research Unit, Umeå University, SE-901 81 Umeå, Sweden.
Objectives:
In a previous pilot study, we found an association between high factor XII levels and risk of haemorrhagic stroke suggesting that factor XII is a risk marker for intracerebral haemorrhage (ICH). The aim of this study was to further investigate the association between factor XII and risk of ICH in a larger population.
Materials And Methods:
This study was conducted as a prospective nested case-referent study. All participants underwent a health examination and blood sampling for factor XII analysis at baseline. Cases were defined as participants who were diagnosed with a first-ever ICH between 1985 and 2000. Two referents were matched to each case.
Results:
We identified 70 individuals with first-ever ICH and 137 matched referents who had undergone a health examination and donated blood samples before the ICH event. The mean age was 54 years, and 33% were women. The median time-to-event was 3.5 years (range 0.04 to 10.2 years). Conditional logistic regression showed no association between factor XII and risk of ICH, (odds ratio 1.06 per SD; [95% confidence interval: 0.57-1.97] in a multivariable model).
Conclusions:
A previous finding of an association between high concentration of factor XII and risk of ICH could not be replicated in this larger study.
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