Association of obesity and treated hypertension and diabetes with cognitive ability in bipolar disorder and schizophrenia.
OBJECTIVE
People with bipolar disorder or schizophrenia are at greater risk for obesity and other cardio-metabolic risk factors, and several prior studies have linked these risk factors to poorer cognitive ability. In a large ethnically homogenous outpatient sample, we examined associations among variables related to obesity, treated hypertension and/or diabetes and cognitive abilities in these two patient populations.


METHODS
In a study cohort of outpatients with either bipolar disorder (n = 341) or schizophrenia (n = 417), we investigated the association of self-reported body mass index and current use of medications for hypertension or diabetes with performance on a comprehensive neurocognitive battery. We examined sociodemographic and clinical factors as potential covariates.


RESULTS
Patients with bipolar disorder were less likely to be overweight or obese than patients with schizophrenia, and also less likely to be prescribed medication for hypertension or diabetes. However, obesity and treated hypertension were associated with worse global cognitive ability in bipolar disorder (as well as with poorer performance on individual tests of processing speed, reasoning/problem-solving, and sustained attention), with no such relationships observed in schizophrenia. Obesity was not associated with symptom severity in either group.


CONCLUSIONS
Although less prevalent in bipolar disorder compared to schizophrenia, obesity was associated with substantially worse cognitive performance in bipolar disorder. This association was independent of symptom severity and not present in schizophrenia. Better understanding of the mechanisms and management of obesity may aid in efforts to preserve cognitive health in bipolar disorder.
Department of Psychiatry, University of California at San Diego, La Jolla, CA, USA; VA San Diego Healthcare System, La Jolla, CA, USA.
Colin A
CA
Depp
Martin
M
Strassnig
Brent T
BT
Mausbach
Christopher R
CR
Bowie
Paula
P
Wolyniec
Mary H
MH
Thornquist
James R
JR
Luke
John A
JA
McGrath
Ann E
AE
Pulver
Thomas L
TL
Patterson
Philip D
PD
Harvey
D000328:Adult; D001714:Bipolar Disorder / Q000150:complications*; D015992:Body Mass Index; D003072:Cognition Disorders / Q000150:complications* / Q000209:etiology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D009765:Obesity / Q000453:epidemiology / Q000209:etiology*; D010045:Outpatients; D011569:Psychiatric Status Rating Scales; D012044:Regression Analysis; D012559:Schizophrenia / Q000150:complications*; D057566:Self Report
bipolar disorder; diabetes; health risk factors; hypertension; neuropsychology; obesity; psychosis