Abstract Background Primary insomnia (PI) is a prevalent sleep disorder associated with heightened risks of cardiovascular diseases (CVD), including hypertension and coronary artery disease. This elevated risk is thought to arise from a state of persistent central nervous system hyperarousal, which may lead to autonomic dysfunction and systemic inflammation. While acupuncture has shown promise in treating PI, prior evaluations have largely relied on subjective scales, lacking objective neurophysiological evidence linking its effects to CVD-related pathways. Purpose This study aimed to objectively evaluate the efficacy of acupuncture in patients with PI by analyzing resting-state electroencephalography (EEG) microstates and spectral power, and to explore whether acupuncture-induced neural changes correspond to patterns relevant to cardiovascular risk modulation. Methods Thirty healthy controls and 60 PI patients were recruited. PI patients were randomized into a verum acupuncture group (n=30, 1 dropout) and a sham acupuncture group (n=30, 3 dropouts). Acupuncture was administered at Baihui (GV20), Sishencong (EX-HN1), bilateral Taichong (LR3), Neiguan (PC6), Zusanli (ST36), Sanyinjiao (SP6), and Shenmen (HT7) for 30 minutes per session, three times weekly over four weeks. Subjective sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI) and Insomnia Severity Index (ISI) at baseline, 2 weeks, and 4 weeks. Resting-state EEG was recorded at baseline and post-treatment. Microstate and power spectrum analyses were applied to identify objective neural correlates of hyperarousal, with implications for cardiovascular risk pathways such as autonomic regulation. Results Compared to healthy controls, PI patients exhibited significantly decreased θ and α power across multiple brain regions, along with reduced duration and coverage of microstates A and C, and increased β power in FP2 and increased incidence/coverage of microstate D (all P0.05). After treatment, the verum acupuncture group showed improved PSQI and ISI scores, increased θ power in P7, increased α power in CP6, and prolonged microstate C duration, alongside reduced incidence and coverage of microstate D (all P0.05). These changes reflect a normalization of hyperarousal-related EEG patterns. No significant improvements were observed in the sham group (P0.05). Conclusion PI is characterized by abnormal cortical activity consistent with sustained hyperarousal, which may underlie its association with cardiovascular risk. Acupuncture effectively improves both subjective sleep quality and objective EEG markers of hyperarousal, suggesting a potential role in modulating central nervous system pathways relevant to CVD risk. These findings provide neuroelectrophysiological support for acupuncture’s therapeutic benefits in PI and its broader implications for cardiovascular health.
Ji et al. (Thu,) studied this question.