Posted by Phillipa on April 12, 2010, at 20:24:13
I didn't know that some thought lithium dulls cognition maybe why some go off meds. Phillipa
Bipolar Illness, Not Lithium, Impairs Cognitive Function
NEW YORK (Reuters Health) Apr 08 - Lithium may not have harmful neuropsychological effects on patients with bipolar illness, new research suggests. Instead, the disease itself appears to be responsible for the cognitive deficits seen in these patients.In fact, the researchers say, lithium "looks quite safe," and cognitive impairment "seems to be independent of medication" in these individuals.
The finding that bipolar patients in remission have cognitive deficits not related to medication is an important one, "because the vast majority of studies claiming to find such deficits have been conducted on patients taking medication or acutely ill," say lead author Dr. Carlos Lopez-Jaramillo and his colleagues.
Dr. Lopez-Jaramillo of the Universidad de Antioquia in Medellin, Colombia, and associates administered a series of cognitive function tests to three groups: 20 patients with bipolar disorder who had been euthymic for at least six months and were not taking medication; 20 patients with bipolar illness, also in remission, who had been on lithium monotherapy at therapeutic blood levels (0.6-1.2 mEq/L) for at least two months; and 20 healthy controls with no history of mental illness.
Compared to the controls, the medicated patients scored worse in the cued recall and cued delayed recall variables of the test for associative memory with semantic increase; the recognition of logical memory of the Wechsler Memory Scale; and the free short recall, cued short recall, and cued delayed recall variables of the California Verbal Learning Test (CVLT).
But when the researchers compared the unmedicated bipolar patients to the healthy controls, these patients showed the same deficits as the medicated patients. In addition, they also scored worse than controls on the Wechsler Scale's backward digits and recognition of logical memory variables.
There were no significant differences between the medicated and unmedicated groups on neuropsychological variables, according to the report, which appeared online March 23rd in the Journal of Clinical Psychiatry.
While the study is small, the researchers note that it is difficult to find truly euthymic bipolar patients who are either unmedicated or only taking lithium, "because polypharmacy is a clinical reality in bipolar disorder." Gathering the current sample, they add, took several years.
Dr. Lopez-Jaramillo and his colleagues suggest that bipolar patients may perform worse on tests of verbal and visual-verbal episodic memory because they have more difficulty using "semantic associations that favor their information storing and recall processes."
"It has been reported that some patients might stop...treatment as a consequence of their concern for the negative effects that lithium could bear on cognition, substantially increasing their risk of relapse as a consequence," the authors note.
But despite concerns that lithium could slow processing and psychomotor performance, the current study found no difference in these abilities between the medicated and unmedicated bipolar patients, they add.
The patients' verbal memory deficits "are not explained by medication or by lithium monotherapy, but by the condition itself," the investigators conclude.
J Clin Psychiatry 2010.
poster:Phillipa
thread:943242
URL: http://www.dr-bob.org/babble/20100406/msgs/943242.html