Researchers at  University of Michigan, Ann Arbor have recently reached some arguable findings, after an analysis of statistical data showed that there’s an uncanny link between the people who show up at the hospital for cat bites related wounds and depression. Also, most people who had been both diagnosed with depression at some point in their lives and bitten by cats were women. The results are most puzzling of course, and as for conclusions – the researchers only attempted to make guesses in their paper published in the journal PLOS ONE.

Usually, I take little interest in studies that make a case out of findings that aren’t supported by a direct cause and effect link. This time, however, I’m inclined to be more receptive because of the sheer volume of study participants. The health records of some  1.3 million people over 10 years were peered through. The researchers found that 41% of the those who came to the hospital after being bitten by cats were also treated for depression at some point; of these 86% were women. So, what does this tell us? Being bitten by cats makes you depressed? Being depressed causes you to be bitten by cats? If so, do cats get some special cues from depressed individuals that causes them to go berserk, rabidly biting their owners afterward? These are humorous and, maybe, preposterous thoughts,  but in the end it all might boil down to circumstances.

First of all, numerous studies have found that owning a pet greatly helps coping with depression, offring multiple health benefits, both physical and mental. For instance, pet ownership has been shown to reduce elevated blood pressure caused by mental stress even better than antihypertensive medications. Pets provide social support in the times of sorrow and provide great comfort by always being near to their owners. For people living alone, cats are the best choices to help them cope with loneliness and possible depression, a study in Switzerland found. With this in mind, it makes sense that a large proportion of depressed individuals own cats, and seeing how a lot of women, depressed or otherwise, own cats the current findings could be explained.

The researchers, however, state that it may be possible for depressed people to act in a way that makes cats more likely to bite them. The depressed make less eye contact and cats, like other domesticated animals (dogs, pigs, horses) are known to respond to human behavioral cues like gestures, gaze, and focus. Another intriguing possibility, one that’s sure to causes shivers and fright, is that of Toxoplasma gondii infection. The parasite is carried by cats and carried in their feces. When it infects a human host, it causes alteration to the brain and causes erratic behavior. Infected have been reported to engage in  self-inflicted violence and there seems to be a link between this bacterial infection and increased suicide rates in women.

Bottom line? A conclusion that explains this surprising link between cat aggression and human depression is yet to be satisfyingly drawn.  Still, they write that it makes sense for doctors to screen cat bite victims for depression.

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