Covering the period 1998 to 2007, it involved 29 patients attending a lithium treatment clinic who had been commenced on lithium treatment for affective disorders such as depression, bipolar disorder and schizoaffective disorder. The study reported that no new cases of dementia developed over a mean follow-up period of 38 months. Given the limitations, the authors tentatively suggest that lithium may have a protective effect against cognitive decline in people with affective disorder and in those with concurrent affective disorder and cognitive impairment.
Very rare and unusual causes account for about 5% of cases of dementia. Variant CJD, a human prion disease, is one of the rarer causes of dementia, caused when meat from cattle infected with bovine spongiform encephalopathy (BSE) is eaten. It typically affects younger adults. ROI has the second highest rate of vCJD in the world, with four cases reported to date. To complement existing measures adopted to contain the risk of vCJD transmission from transfusion of blood or blood products originating from subclinical carriers of the disease, prion-removing filters have been developed to reduce the risk of vCJD transmission.