Common parasite that lives in the bodies of 10 - 20% of Americans linked to a sevenfold higher risk of attempted suicide

http://www.medicalnewstoday.com/articles/249230.php

 

Testing positive for a common parasite that lives in the bodies of 10 - 20% of Americans is linked to a sevenfold higher risk of attempted suicide, according to new research.

I found this article pretty interesting since it furthers the hypothesis that depression is a biological disorder with real, physiological, biochemical roots. It proposes that inflammation and other effects within the brain caused by a common parasite which up to 1 in 5 people host can lead to a drastically increased "risk of attempted suicide".

However, I would like to know exactly what this means. The supposed "risk" is measured on a "suicide assessment scale" - but surely the risk of suicide is something which is subjective to each person. Also, the perception of the "risk of suicide" in the subject could vary greatly depending on the background and/or mental health of the person evaluating the risk.

One must also bear in mind that the sample only included 84 people - 54 attempted suicide patients and 30 controls. All were adults. I'd expect to see a sample of at least a few hundred for a study like this.

Nonetheless, this paves the road for a whole new area of study - the physiological effects of parasites on the brain and the psychological impact of these effects.