뇌 자극 연구, 우울증 치료 기간 단축과 인지 저하 억제에 가능성
최근 연구에 따르면 경두개 자기자극(TMS)은 기존 6주 치료를 5일 집중 프로토콜로 압축해도 유사한 효과를 보일 수 있다. 또 경도 인지장애 노인에서 저용량 lithium이 2년 동안 언어 기억 저하를 위약보다 늦추는 신호가 관찰됐으며, **amyloid beta** 수치가 높은 환자에서 보호 효과가 더 크게 나타날 가능성이 제기됐다.
A brain stimulation therapy for depression can show results in as little as a workweek, according to a new study. Transcranial magnetic stimulation (TMS) typically requires daily clinic visits over six to eight weeks, a rather rigorous schedule for people grappling with depression. But patients can see benefits in as little as five days if they undergo five sessions per day, researchers will report in the June issue of the Journal of Affective Disorders.
This "five-by-five" treatment eased depression scores on par with conventional TMS among a small group of patients, researchers found. To see if TMS could be applied more efficiently, researchers had 40 patients receive an accelerated protocol of five sessions per day for five days in a row. Each session took nine to 15 minutes. Their progress was compared to another group of 135 patients who received conventional TMS therapy of one session a day, five days a week, for six weeks.
All of the patients suffered from depression that had not been eased using antidepressant medications. Both groups showed meaningful reductions in depression symptoms, with no statistically significant difference in outcomes, researchers said. Interestingly, half of the five-by-five patients did not show an immediate improvement in their depression, but showed a 36% decrease in symptoms after two to four weeks.
TMS applies magnetic pulses to stimulate specific areas of the brain through electrodes placed on a patient's scalp. Large studies have shown that TMS can significantly reduce depression symptoms in 60% to 70% of patients, with 25% to 35% becoming completely symptom-free, researchers said in background notes. In fact, most insurance plans cover TMS treatment for depression, researchers said.
However, researchers noted that this was not a formal clinical trial, and that larger trials will be needed to confirm their findings.
In separate research, the mood disorder drug lithium might have brain benefits beyond simply warding off depression and anxiety. A pilot clinical trial has found that low-dose lithium tablets might help slow verbal decline among seniors with mild cognitive impairment, researchers reported March 2 in JAMA Neurology.
Seniors taking lithium for two years had better ability to remember and recall words and sentences compared to others taking a placebo, the study found. The results weren't definitive, but provided signs positive enough to warrant larger follow-up studies, researchers said.
For the trial, researchers recruited 80 seniors with an average age of 72, and randomly assigned them to take either low-dose lithium or a placebo for two years. Participants underwent cognitive tests and brain scans to assess the drug's effect on brain function and structure.
People taking lithium had a slower rate of decline on a test of verbal memory, which is something known to deteriorate early in Alzheimer's disease, researchers said. Brain imaging scans showed that the hippocampus – a critical region for memory – shrank over time in both groups.
However, the scans and tests suggested a larger protective effect among people whose brains contained higher levels of amyloid beta, a toxic protein linked to Alzheimer's. The trial was launched in 2018, when blood tests for amyloid beta weren't available. As a result, participants were enrolled based on their clinical symptoms alone, and only some turned out to be amyloid-positive. This could have diluted the study's ability to suss out stronger effects of lithium among these patients, researchers said.
The results also showed that low-dose lithium can be taken safely by seniors. The team now is seeking support for a larger, more definitive clinical trial.