Leonardo Tondo, MD, a prominent researcher on lithium and affective illness, who is on the faculty of McLean Hospital/Harvard Medical School and the University of Cagliari, Italy, reviewed studies on lithium’s effects for suicide prevention. Ecological studies in this field have found an association between higher amounts of lithium in the drinking water and lower suicide rates.These “high” amounts of lithium are equivalent to about 1 mg/d of elemental lithium or somewhat more. Conversely, other studies did not find such an association, but tended to look at areas where lithium levels are not high (ie, about 0.5 mg/d of elemental lithium or less). Nonetheless, because these studies are observational, causal relationships cannot be assumed. It is relevant, though, that lithium has been causally associated with lower suicide rates in randomized clinical trials of affective illness, compared with placebo, at standard doses (around 600-1200 mg/d of lithium carbonate).
Christoforos Giakoumatos, MD, from the Harvard South Shore Psychiatry residency training program, reviewed the scientific literature on lithium’s neuroprotective effects. Extensive animal studies have shown that lithium keeps neurons alive longer. Some human studies also suggest a benefit of lithium in prevention or amelioration of dementia, consistent with its neurobiological benefits. These data support further work to clarify how much, and to what extent, lithium could be useful in human neurodegenerative diseases.
Othman Mohammad, MD, also from the Harvard South Shore program, examined lithium use in children and adolescents, and reviewed a number of randomized trials that showed evidence for efficacy and short-term safety with lithium in acute manic episodes, especially in adolescents. Of note, similar randomized data did not show benefit with divalproex, indicating that there is relatively more evidence for lithium’s efficacy and safety in adolescence.