rosie -

I think your excellent analysis proves the point that however you slice it (major depression, depressive symptoms, situational, biological, pre-or-post diagnosis), depression more often than not, in one or more of it's various forms and manifestations, coincides with a PD diagnosis.

The problem is deciding if it exists, teasing out the source and finding the appropriate treatment.

The challenge has been just getting doctors to acknowledge and patients to accept the fact that "depression" shadows PD - if we can scale that mountain, the opportunity for improvement of overall health exists because depression, in any and all of its forms, can be treated.

As an aside, I was just reminded of how crucial it is to actually read not only the entire paper (as opposed to abstract) but also to read the papers cited, or t least some of them.

The authors of the review study I mentioned earlier, Frisina et al, cited a 1990 study by Mayberg et al as having found that:

“Depressed PD patients show metabolic abnormalities during PET scans in both the caudate and inferior frontal cortices as compared to non-depressed PD patients and aged-matched healthy controls.”

But then Frisina et al say:

“Though these studies point to a biological etiology of PD depression, one criticism is that while depressed and non-depressed PD patients are compared, these studies do not directly compare depressed PD patients to non-neurologically ill depressed patients. This leaves open the possibility that depression alone could also contribute to metabolic deficits, rather than the effect of PD.”

Which gives the clear impression, to me, at least, that the intent of the Mayberg study was to show that metabolism in depressed PWP was different from that of non depressed PWP, and that that was evidence for a biological etiology of depression in PD.

Well that seemed so ridiculous to me that I paid the $30 for the Mayberg paper and that is not at all what that paper was about.

On the contrary, Mayberg et al hypothesized that metabolic changes seen via in vivo imaging in depressed people without PD would ALSO be seen in depressed PWP – this would allow the use of in vivo imaging to “discriminate patients with PD who are depressed from those who are not,” based on the similarities between depressed PWP and depressed people without PD.