Friday, November 20, 2009

Sorry Philip, This Study Won't Change Anything

This study (1) published in the British Journal of Psychiatry was first brought to my attention on the Furious Seasons blog (2).

This study recruited the following subjects, "Parents with bipolar disorder were identified from their involvement in a mood disorders subspecialty programme and/or genetic studies as previously described. Briefly, suitable families were identified through a proband who met DSM–IV criteria for bipolar disorder based on Schedule for Affective Disorders and Schizophrenia – Lifetime version (SADS–L) research interviews conducted by an experienced research psychiatrist. Final diagnosis was made on masked consensus review involving two additional research psychiatrists using all available clinical information

All consenting children (n = 207) from eligible families (n = 105) between the ages of 8–25 years were enrolled. The duration of the longitudinal study ranged from 1 to 15 years. Children completed Kiddie–SADS–PL (Present and Lifetime version) interviews conducted by a child and adolescent psychiatrist at enrolment, annually or at any time symptoms developed, up until their 30th birthday. DSM–IV diagnoses were made using all available clinical information on a masked consensus basis. 64% of all major episodes were prospectively captured. Any retrospective data used were based on participant and parent recall, and verified through a review of all available clinical documentation."

Here is a brief summary of the results: "Of the 207 participants, 67 met DSM-IV lifetime criteria for at least one major mood episode (i.e., depression, mania, hypomania, mixed). Their mean age at analysis was 24 (s.d.=5) years and 67% were females. in total, 16% had been admitted to hospital at least once in their lifetime and 18% had a lifetime history of psychotic symptoms in episodes. The mean age at onset of the first major mood episode was 17 (s.d.=4) years and no one experienced an onset prior to 12 years."

Overall, this study confirmed what is already known about bipolar disorder. Average age of onset was 17 (+/-4) years. First episode is typically depressive, as is the second episode. Average cycle length was 31 months. No mood episodes occurred before the age of 12. This is the typical information anyone can get by reading the DSM-IV.

Philip added this brief commentary on his site regarding these results,
"Someone alert Joe "Agitation is Mania!" Biederman and CABF! Seriously, that's a pretty stunning finding and certainly confirms what other researchers elsewhere in the world have written."

Unfortunately, Joe Biederman probably didn't even read this study, since, from his point of view, it's completely wrong. It's wrong because these researchers were using the old rule book (i.e., DSM-IV). People like Biederman, Goodwin, and Akiskal et al have changed the official rule book (actually each one has their own rule book).

Biederman asserts that agitation is pathognomonic for pediatric bipolar. Others have created such ridiculous terms as "soft bipolar disorder," "subthreshold hymania," and the absurd "Bipolar III 1/2." Check out CLpsych's critique (
) of the "COBY-established criteria for BP-NOS" (4) for an example of how such rule changes can be misused.

Some say that we are simply adopting a dimensional paradigm of illness as opposed to the rigid traditional paradigm. What makes the dimensional view superior to the traditional paradigm? Is it because more people are eligible for a diagnosis? Is it that more people are eligible for prescription medications? The bipolar spectrum paradigm certainly allows more of the population to have mental health diagnoses, and it allows drug companies to get more bang for their advertising bucks.

Some mental health diagnoses seem undeniable (e.g., depression, bipolar I disorder). Come DSM-V, schizoaffective disorder, Apserger's, borderline personality disorder (which might be reduced to an axis I disorder), and narcissistic personality disorder might disappear from our vernacular all together.

Bottom line: We're making this shit up!

Duffy A, Alda M, Hajek T, & Grof P (2009). Early course of bipolar disorder in high-risk offspring: prospective study. The British journal of psychiatry : the journal of mental science, 195 (5), 457-8 PMID: 19880938

1 comment:

Neuroskeptic said...

"Some say that we are simply adopting a dimensional paradigm of illness as opposed to the rigid traditional paradigm. What makes the dimensional view superior to the traditional paradigm?"

Good question. People just generally assume that a dimensional view is somehow more intelligent because it "captures the fact that mental illness exists on a spectrum" and doesn;t "pigeon hole people".

But nowhere else would this be considered a good thing. We don't have a dimensional view of infectious diseases or brain tumours. In fact one sign that a field of science has matured is when you can look at an apparently messy collection of things and pigeon-hole them into valid categories e.g. you can diagnose someone with bacterial meningitis vs. viral meningitis.

The fact that DSM-IV categories are generally not very valid doesn't mean we should give up on the idea of categories altogether.