A team of UK scientists have discovered that lithium may potentially be an effective preventative treatment for dementia.
The team, comprised of specialists from the University of Cambridge, retrospectively examined the health record of around 30,000 patients from Cambridgeshire and Peterborough NHS Foundation Trust. The patients were all over 50 years old and used NHS mental health services between 2005 and 2019. The results demonstrated that patients administered lithium were less likely to develop dementia than those who did not, suggesting it may be an effective preventative treatment for dementia.
The research findings, which were supported in part by the UK Medical Research Council and the National Institute for Health Research (NIHR) Cambridge Biomedical Research Centre, are published in the journal PLOS Medicine.
A threat to global health
Statistics show that around one million people in the UK alone are affected by dementia, with over 55 million people having the condition worldwide, with Alzheimer’s disease being the most common form. Despite the disease being the leading cause of death in elderly Western populations, there is currently no available preventative treatment for dementia.
Dr Shanquan Chen from Cambridge’s Department of Psychiatry, the paper’s first author, said: “The number of people with dementia continues to grow, which puts huge pressure on healthcare systems. It’s been estimated that delaying the onset of dementia by just five years could reduce its prevalence and economic impact by as much as 40%.”
Earlier studies have suggested that lithium could be employed as a treatment for individuals who have already been diagnosed with dementia or early cognitive impairment, although it is unclear whether it can delay or prevent dementia development due to studies being limited in size. However, lithium is used as a mood stabiliser for conditions such as depression and bipolar affective disorder.
Chen commented: “Bipolar disorder and depression are considered to put people at increased risk of dementia, so we had to make sure to account for this in our analysis.”
Pioneering a preventative treatment for dementia
To analyse the potential of lithium as a dementia treatment, the Cambridge team analysed the health records of 29,618 patients, 548 who had been treated with lithium and 29,070 who had not. The cohort’s mean age was just under 74 years, and 40% were male. All participants received at least a one-year follow-up appointment and had not been previously diagnosed with dementia or mild cognitive impairment.
In the group that received lithium, 53 (9.7%) were diagnosed with dementia; for the group not receiving lithium, 3,244 (11.2%) were diagnosed with dementia. The team controlled for factors such as smoking, other medications, and other physical and mental illnesses, finding that lithium was associated with a lower risk of dementia for both short and long-term users.
However, due to the overall number of patients receiving lithium being small and this being an observational study, the researchers stated that larger clinical trials are needed to establish lithium as a preventative treatment for dementia. Furthermore, an additional limitation of the study was the number of participants that had already been diagnosed with bipolar disorder – a condition associated with an increased risk of dementia.
Chen commented: “We expected to find that patients with bipolar disorder were more likely to develop dementia, since that is the most common reason to be prescribed lithium, but our analysis suggested the opposite. It’s far too early to say for sure, but it’s possible that lithium might reduce the risk of dementia in people with bipolar disorder.”
