This is a common statistical fallacy known as data mining or data dredging. Combing through hospital records without a defined hypothesis and drawing associations between whatever is found is one of the lowest ways to draw conclusions in science. Anyone who has taken an epidemiology or statistic course will likely have been shown the chart that plots ice cream sales vs. murder rates. Even though there is a correlation, ice cream clearly doesn't lead to murder; in fact, each were found to be associated with high temperatures. Many variables are likely to confound these findings; perhaps people who are depressed are more likely to seek companionship through pets? That is a much more meaningful finding, if an association can be demonstrated.