TOPLINE:
Transcranial alternating current stimulation (tACS), a noninvasive technique that uses low-intensity electrical currents to modulate brain activity, is an effective intervention for treating chronic insomnia, especially in older people, results of a relatively large study suggested.
METHODOLOGY:
- The double-blind study included 124 adults with chronic insomnia (difficulty falling asleep or maintaining sleep and early morning awakening occurring at least three times a week over 3 or more months), mean age about 51 years, from two centers in China who were randomized to receive either tACS (active group) or sham tACS (control group).
- Patients underwent 20 40-minute sessions over 4 weeks; the tACS intervention involved positioning three electrodes on the scalp and applying a current of 15 mA at a frequency of 77.5 Hz, whereas the control group received no stimulation.
- Primary outcome measures included total score on the Chinese version of the self-report Pittsburgh Sleep Quality Index (PSQI), sleep onset latency, total sleep time (TST), sleep efficiency, sleep quality, and daily disturbances (such as fatigue and attention deficits).
- Secondary outcomes included Hamilton Depression Scale (HAMD), Hamilton Anxiety Scale (HAMA), and Clinical Global Impression scale (including Clinical Global Impression Severity of Illness [CGI-SI], Clinical Global Impression Global Improvement [CGI-GI], and Clinical Global Impression Efficacy Index [CGI-EI]).
- As rates of chronic insomnia increase with age, researchers explored the influence of age on treatment benefits by dividing participants into two age groups (< 50 years and ≥ 50 years).
TAKEAWAY:
- Among the 120 participants who completed the trial, tACS resulted in a statistically significant decrease in insomnia severity compared with the control group (estimated advantage [number of points on PSQI scale], 2.61; 95% CI, 1.47-3.75; P < .001).
- There were also statistically significant estimated advantages of tACS for TST (−0.65; 95% CI, −1.06 to −0.24; P = .002), sleep efficiency (1.05; 95% CI, 0.48-1.62; P < .001), sleep quality (0.82; 95% CI, 0.29-1.34; P = .003), and daily disturbances (0.91; 95% CI, 0.58-1.25; P < .001).
- tACS exhibited significant effects on CGI-SI (0.84; 95% CI, 0.38-1.30; P < .001), CGI-GI (0.74; 95% CI, 0.42-1.06; P < .001), and CGI-EI (−0.71; 95% CI, −1.02 to −0.39; P < .001) but not on total scores of HAMD and HAMA, possibly because of the relatively low baseline levels of depression and anxiety among study subjects, said the authors.
- In the older, but not younger, group, tACS treatment had a significant benefit in sleep quality, sleep efficiency, PSQI total score, CGI-SI, CGI-GI, and CGI-EI.
IN PRACTICE:
“These significant findings contribute substantially to promoting evidence-based practices and facilitating the development of innovative treatment strategies for chronic insomnia,” the investigators wrote.
SOURCE:
The study was conducted by Xiaolin Zhu, Beijing Huilongguan Hospital, Peking University Huilongguan Clinical Medical School, Beijing, China, and colleagues. It was published online in the Journal of Psychiatric Research.
LIMITATIONS:
The follow-up period was limited to 8 weeks, so longer follow-up studies are needed to explore the sustained effects of tACS on chronic insomnia. Severity of chronic insomnia was limited by using the self-report PSQI, and not objective measures of insomnia such as polysomnography and wrist actigraphy. The age of study subjects ranged from 22 to only 65 years.
DISCLOSURES:
The study was supported by the Beijing Municipal Science and Technology Commission. The authors had no relevant conflicts of interest.
A version of this article first appeared on Medscape.com.