[Skip to Navigation]
Comment & Response
March 2018

Lithium and Dementia

Author Affiliations
  • 1University of New South Wales, Sydney, Australia
JAMA Psychiatry. 2018;75(3):301-302. doi:10.1001/jamapsychiatry.2017.4187

To the Editor In 1968, Kline1 noted that lithium was a “different key” for dealing with affective and possibly other psychiatric disorders and asked the rhetorical question, “How many locks will it fit?” Kessing and colleagues2 linked lithium in drinking water with dementia incidence, suggesting another lock for the lithium key. Lithium’s multifaceted, potentially neuroprotective actions do give it plausibility as an “elixir.” However, the study is not without its limitations. The lithium intake was based on sampling of waterworks that provide water to 42% of the population, and the sampling was done for 4 years (2009-2013) and extrapolated to a lifetime. Many potential confounders were not taken into consideration. A major source of lithium is diet, and some bottled water contains lithium. Both these factors are not accounted for in this study. No effort was made to substantiate the differential exposure by obtaining blood or hair lithium levels. Dementia rates are confounded by education, socioeconomic, and multiple health factors, which were not considered in the analysis. Furthermore, the explanation for the observation that low levels of exposure increased the risk of dementia was not satisfactory, and the lack of specificity for a neurodegenerative disorder again raises doubts about the veracity of this finding.

Add or change institution