The Professional Organization of Arizona Psychiatrists

A recent study indicates that elderly patients who take Lithium for bipolar disorder are less likely to develop Alzheimer's disease.

Patients with bipolar disorder have a higher risk for developing dementia, but researchers at the University of Sao Paulo, Brazil, found that chronic lithium therapy could reduce the rate of the condition to a level similar to that for the general population. They noted that "Lithium inhibits glycogen synthase kinase-3, a key enzyme in the metabolism of amyloid precursor protein and the phosphorylation of tau protein, which are critical steps in the formation of neuritic plaques and neurofibrillary tangles".

The study involved comparing the prevalence of Alzheimer's disease in 66 bipolar disorder patients from Brazil aged 60 years or older who had been taking lithium for at least the previous 6 months with that in 48 similar patients who had been taking mood-stabilizing drugs other than lithium.

Three (5%) of the patients taking lithium developed Alzheimer's disease, compared with 16 (33%) of the other patients. The prevalences of mild cognitive impairment were 20% and 25%, respectively.

The study was published in the British Journal of Psychiatry noting that the prevalence of Alzheimer's disease among the patients taking lithium was similar to that for the elderly general population in Brazil, at around 7%.