new visualization of comorbidity shows bipolar-schizophrenia-autism link, and much more

July 11, 2007

Columbia University researchers have created a visualization of disease comorbidity using health records from 1.5 million people (article and full-text paper). There’s a lot they’ll be able to do with this – look for genetic links, look to see if some conditions protect from other conditions, look for potential environmental triggers like bacterial or viral infections.

This sounds awesome in general – people can process complex information about associations much faster when represented visually than when they see a bunch of numeric correlations. (Way to go, information usability!)
They find that bipolar, autism, and schizophrenia are associated (quotes from the paper):

We estimate that {approx}20–60% of autism-predisposing variations also predispose the bearer to bipolar disorder, and 20–75% of autism-predisposing variations also predispose the bearer to schizophrenia. It is therefore extremely likely that there is a three-way positive correlation among autism, bipolar disorder, and schizophrenia, a correlation that probably arises from a genetic variation that predisposes to all three disorders.

If so that’s extremely interesting, although I wonder how much of a link between autism and schizophrenia is due to the two being mistaken for each other (or perhaps the overlap in predisposing genes is why the two are mistaken for each other – our diagnostic categories are attempting to clearly delineate fuzzy categories).

Also, everything under the sun is associated with autism, apparently (I wonder whether there’s a causal relationship, and if so which way, or whether it’s third variables, or all of the above):

[A]utism, which typically manifests before the affected child is 3 years old, has a strong positive correlation with a number of neurological disorders, some of which have a late-age onset…: attention deficit, epilepsy, cerebral palsy, depression, schizophrenia, bipolar disorder, neurofibromatosis, Parkinson’s disease, and migraine. Our estimated significant overlap between autism and tuberculosis may indicate that both diseases are associated with genetic changes weakening the immune system.

They also mention associations between allergies/autoimmune disorders and autism, schizophrenia, and bipolar disorder. And here’s something totally new: female breast cancer is negatively associated with schizophrenia and bipolar disorder. They proposed an explanation involving schizophrenia and bipolar being associated with increased probability of abnormal cell death in some tissues, and breast cancer being associated with an increased probability of abnormal cell proliferation. And they mention that tamoxifen (a breast cancer treatment drug) can help treat bipolar disorder – I’ll try to follow up on that in a future post.

And the credits go to: Andrew Rzhetsky, David Wajngurt, Naeun Park, and Tian Zheng of the University of Columbia. And any unnamed undergraduate or graduate assistants.

(For anyone who’s requested an entry on a specific topic: I haven’t forgotten you, I’ve just been too busy to do background research because of moving this weekend, and have been doing stuff I could sit down and type out instead. Entries on schizoaffective disorder, kindling, worries about personality change on meds, and lots of stuff on culture coming up, among other things.)