Exploration of Quantitative-Effectiveness Association between Acupuncture Temporal Parameters and Stable Chronic Obstructive Pulmonary Disease: A Dose-Response Meta-Analysis Of Randomized Controlled Trials

Introduction: Chronic Obstructive Pulmonary Disease (COPD) is a globally common chronic respiratory disease with a high morbidity and mortality rate. Acupuncture has been proven effective for COPD. A dose-response meta-analysis was conducted to assess the correlation between the acupuncture temporal parameters(session, frequency, and duration) and its effectiveness on stable COPD Methods: Acupuncture randomized controlled trials (RCTs) on COPD were searched in eight databases from their inception to June 2023. RCTs that compared acupuncture with conventional treatment, sham acupuncture, or no acupuncture were included. The "doses" were defined as the acupuncture session, frequency, and duration. The outcomes included FEV1% and 6WMD. The quality of the literature was evaluated using RoB2 and STRICTA, the dose-response relationship was modeled using robust error element regression (REMR), and meta-analysis was operated by R4.2.1 and Stata 15.0. Results:Out of 1669 records, 15 RCTs with 981 participants were finally included in the meta-analysis. The findings revealed a significant enhancement in FEV1% (MD=5.17, 95%CI: 4.23-6.11) and 6WMD (MD=48.65, 95%CI: 25.04-72.25) among stable COPD patients with acupuncture treatment. The relationship between the acupuncture session, duration, and FEV1%, 6WMD followed a "up" curve pattern, while the relationship between acupuncture frequency and FEV1%, 6WMD exhibited logarithmic growth. Firstly, After 12 acupuncture sessions, FEV1% increased by 6.77% (95%CI: 4.53-9.01), and 6WMD increased by 35.90m (95%CI: 19.02-52.79). The peak improvement in FEV1% and 6WMD was observed after 18 acupuncture sessions (MD=7.60, 95% CI: 5.30-9.89) and 45 sessions (MD=124.89, 95% CI: 70.63-179.15), respectively. Additionally, weekly acupuncture resulted in a 3.75% improvement in FEV1% (95% CI: 2.63-4.87) and a 43.00m increase in 6WMD (95%CI: 16.73-69.27). Notably, the maximum effects on FEV1% and 6WMD improvement were achieved with different acupuncture frequencies, specifically three times a week (MD=5.84, 95% CI: 5.37-6.30) and once a day(MD=117.97, 95% CI: 74.04-161.89), respectively. Furthermore, after a 28-day duration of acupuncture treatment, FEV1% increased by 4.37% (95% CI: 3.51-5.23) and 6WMD increased by 46.96m (95%CI: 19.57-74.36). During a 60-day period of acupuncture treatment, the FEV1% and 6WMD improvement reached their highest levels at 8.13% (95% CI: 6.68-9.59) and 87.64m (95% CI: 42.86-132.42), respectively. Conclusion: There was a dose-response relationship between the time parameters of acupuncture (session, frequency, and duration) and the efficacy of COPD treatment (FEV1% and 6WMD). The minimal clinically important difference could be achieved after 12 acupuncture sessions and a treatment duration of 28 days. Acupuncture with a medium-frequency (2~3 times per week) over a 2-month period may result in the greatest improvement in FEV1%, while higher-frequency acupuncture (5~7 times per week) for 2 months may lead to the maximum improvements in 6WMD. It indicated that the optimal acupuncture duration for different indicators remains consistent, while the optimal frequencies may differ. To confirm these results, it is necessary to conduct multicenter, large-scale randomized controlled trials.