Burgeoning Associations

There seem to be many more reports these days about associations between two diseases that would normally not be considered related. For instance, the latest news that people with depression are more likely to develop type 2 diabetes, or that people who are diagnosed with Parkinson’s disease are quite often treated with antidepressant drugs in the previous year. And diabetics are more likely to develop mild cognitive impairment (MCI) than the next person.

These associations can sometimes indicate a benefit; i.e. they can work in reverse. For instance, people with migraine are less likely to develop mild cognitive impairment (MCI).

Most of the data for these associations come from large cohort studies that are being reported out after a number of years, such as the Framingham Heart Study or the National Health and Nutrition Examination Studies I and II. The information from such studies is often made widely available to health professionals, who can conduct statistical analyses, looking for suspected associations. It must be made clear that the resultant reports of associations are not evidence of any cause-and-effect, but serve to raise suspicions that require confirmation in prospective studies. These may be extremely difficult and expensive to conduct in many instances, but only such studies can provide the necessary scientific proof . . .