Dementia is the major cause of death in the senior populations of Western countries. Preventive therapies that may even slightly delay the onset of dementia would have a significant public health benefit. There are currently no disease-modifying therapies available. Lithium has been suggested as a possible therapy.
Researchers discovered a relationship that suggests lithium may reduce the risk of acquiring dementia, which affects roughly one million people in the UK. The University of Cambridge researchers undertook a retrospective review of over 30,000 patients’ health records from the Cambridgeshire and Peterborough NHS Foundation Trust. Between 2005 and 2019, the patients were all above the age of 50 and used NHS mental health treatments.
Although the overall number of patients who took lithium was small, the analysis revealed that those who received lithium were less likely to develop dementia than those who did not. Their findings, published in the journal PLoS Medicine, support the idea that lithium might be used to prevent dementia and that major randomised controlled studies could be conducted.
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 percent.
Dr. Shanquan Chen
Dementia is the main cause of death in senior Western cultures, yet there are currently no preventative treatments: more than 55 million people worldwide have dementia, with Alzheimer’s disease being the most common form.
“The number of people with dementia continues to grow, which puts huge pressure on healthcare systems,” said Dr Shanquan Chen from Cambridge’s Department of Psychiatry, the paper’s first author. “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 percent.”
Previous research have advocated lithium as a viable treatment for persons who have been diagnosed with dementia or early cognitive impairment, however it is uncertain if it can postpone or even prevent the development of dementia entirely due to the small size of these studies.
Lithium is a mood stabilizer that is commonly used for bipolar affective disorder and depression. “Because bipolar disorder and depression are thought to increase the risk of dementia, we had to be sure to account for this in our research,” Chen explained.
Chen and his colleagues examined data from Cambridgeshire and Peterborough NHS Foundation Trust patients who sought mental health treatments between 2005 and 2019. Patients were all above the age of 50, had at least one year of follow-up appointments, and had not previously been diagnosed with mild cognitive impairment or dementia.
548 of the 29,618 individuals in the study cohort had had lithium treatment, whereas the remaining 29,070 had not. Their average age was slightly under 74 years, and almost 40% of the patients were male. In the lithium group, 53 people, or 9.7 percent, were diagnosed with dementia. 3,244 people, or 11.2 percent of those who did not get lithium, were diagnosed with dementia.
Lithium use was associated with a decreased incidence of dementia after controlling for factors such as smoking, other drugs, and other physical and mental diseases, both for short and long-term users. However, because the total number of patients taking lithium was limited and this was an observational study, larger clinical studies would be required to prove lithium as a potential dementia treatment.
Another drawback of the study was the small number of patients with bipolar disorder, which is usually associated with an increased risk of dementia. “We expected to find that people with bipolar disorder were more likely to get dementia, because that is the most common reason for prescribing lithium,” Chen explained. “It’s far too early to be certain, but lithium may lessen the risk of dementia in those with bipolar disorder.”
This study backs up previous findings that lithium may be beneficial in the treatment of dementia. More experimental medicine and clinical trials are now required to determine whether lithium is truly beneficial in certain circumstances.
We discovered a link between lithium use and a lower chance of acquiring dementia. This adds to the evidence that lithium may be a disease-modifying medication for dementia and that it is a promising treatment for larger randomised controlled trials (RCTs) in this context.
