Effectiveness and safety of acupuncture therapies for intractable hiccups: a systematic review and network meta-analysis

Intractable hiccups represent an underrecognized medical condition that can cause significant suffering for patients. When they persist for more than 48 hours, they may indicate underlying pathologic processes and drastically interfere with quality of life, causing malnutrition, sleep disturbances, and psychological distress. This systematic review and network meta-analysis assessed the comparative efficacy of different acupuncture modalities in treating this challenging condition. The researchers analyzed 41 randomized controlled trials conducted in China, involving 3,060 patients with intractable hiccups of various etiologies, including stroke, traumatic brain injury, surgery, and oncologic treatments.

The study compared 15 different acupuncture-related interventions, ranging from traditional techniques to combined approaches with conventional medications. The results showed that acupuncture therapies were consistently superior to conventional medications alone in multiple outcomes. Manual acupuncture combined with injection at specific points (MA+AI) emerged as the most effective approach, achieving an 82.2% probability of being the most effective treatment for overall efficacy rate. This combination also showed superiority in improving patients' quality of life, including dietary, sleep, and mental-state aspects.

Combined therapies systematically outperformed monotherapies, suggesting beneficial synergistic effects. Among the monotherapies, auriculotherapy (69.1%) and electroacupuncture (65.4%) were particularly promising. The safety profile was notably favorable, with all studies reporting significantly fewer adverse events in the acupuncture groups than in medication controls, and no serious adverse events were reported. Mechanistically, the observed benefits may be explained by acupuncture's ability to modulate the reflex arc responsible for hiccups across multiple neural levels.

Stimulation of specific points may influence vagal and phrenic afferent pathways, brainstem respiratory centers, and efferent pathways, restoring neurochemical balance and inhibiting abnormal reflex excitability. The clinical implications are substantial, especially considering the limitations of conventional pharmacologic treatments, which frequently cause sedation and extrapyramidal effects. Acupuncture offers an effective non-pharmacologic alternative that may be particularly valuable in vulnerable populations, such as oncology patients or those with multiple comorbidities. However, the study presents important limitations that must be considered in interpreting the results.

All studies were conducted in China and published in Chinese, introducing significant linguistic and geographic bias that limits generalization of the findings to global clinical contexts. Methodological quality varied, with most studies presenting risk of bias related to blinding and allocation concealment. Inconsistency analysis revealed discrepancies between direct and indirect evidence in some comparisons, reducing confidence in certain network estimates. Furthermore, the absence of sham acupuncture control groups limits the ability to distinguish specific acupuncture effects from placebo effects.

For clinical practice, the results suggest that acupuncture, particularly when combined with injections at specific points, may represent a valuable therapeutic option for intractable hiccups. The choice of modality should consider individual patient characteristics, practitioner experience, and resource availability. Future studies should address the identified limitations through rigorously conducted international clinical trials, with standardized methodologies and appropriate control groups, to confirm these promising findings and establish more robust evidence-based guidelines for clinical management of this debilitating condition.