When it comes to debilitating neurological conditions that hamper the quality of life, dementia is among the worst. It leads to a gradual decline in one's cognitive functions such as memory, thinking, and the ability to perform even the simplest of everyday tasks. Offering some hope to millions of sufferers across the world, scientists have suggested that lithium may reduce the risk of developing dementia.
Through a new study, researchers from the University of Cambridge have found that individuals who receive lithium may have a decreased likeliness of developing dementia than those who do not receive the drug; suggesting that lithium may serve as a preventative treatment for dementia. The findings were published in the journal PLOS Medicine.
"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," said Dr. Shanquan Chen, first author of the study, in a statement.
A Global Killer
Over 55 million people across the world suffer from dementia, and its most common form is Alzheimer's disease. Approximately, 10 million new cases are reported worldwide annually. While it mostly affects older people, it is not a result of natural aging. According to the WHO, it is the seventh leading cause of death in the world. Unfortunately, there are no treatments currently available to prevent the onset of dementia.
Lithium, a mood stabilizer, is usually prescribed for the treatment of mental health conditions such as depression and bipolar affective disorder. "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," noted Dr. Chen.
Older studies have propounded that lithium may serve as a potential treatment for people who have already been diagnosed with early cognitive impairment or dementia. Nevertheless, as most of these studies were limited by their size, it is uncertain whether lithium can delay or completely inhibit the development of dementia.
Finding a Link
For the study, the authors used the mental health records of 29,618 patients—obtained from Cambridgeshire and Peterborough NHS Foundation Trust—to conduct a retrospective analysis. The patients had been treated between 1 January 2005 and 31 December 2019. All the individuals were over the age of 50 (mean age= 73.9 years). 40.2 percent of the studied cohort comprised of males and 71 percent were white.
The patients had received a follow-up of at least one year. Also, they had not been diagnosed with dementia or mild cognitive impairment previously. Among the 29,618 patients in the cohort, 548 had been treated using lithium.
Through their examination, the team learnt that in the group that had received treatment with lithium, 53 (9.7 percent) were diagnosed with dementia. However, in the group that had not received lithium, 3,244 (11.2 percent) were diagnosed with dementia.
After considering factors such as other mental and physical illnesses, other prescribed medications, and habits such as smoking, the use of lithium was found to be associated with a lower risk of dementia. This held good for both long and short-term users.
Assessing Lithium's Role
Despite a link being observed, the scientists admitted that the study was bound by a few limitations. For starters, the research was an observational one. Also, as the number of patients within the overall cohort receiving lithium was small, larger clinical trials are required to substantiate that lithium can be potentially used to treat dementia. The study had another limitation: the number of patients in the cohort who had been diagnosed with bipolar disorder. It is commonly associated with the compounding of risk of dementia.
"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," stated Dr. Chen.
Regardless of these limitations, the current research supports previous studies that have proposed that lithium may help tackle dementia. Therefore, further clinical studies can aid in conclusively ascertaining whether lithium can indeed mitigate the condition.