Adults with chronic stable angina who had acupuncture as an adjunct treatment had fewer angina attacks, compared with controls, based on data from a randomized trial of 398 patients in China.
“Acupuncture has been used as nonpharmacologic treatment for several decades, especially to relieve symptoms of myocardial ischemia, improve cardiac function, and prevent recurrence,” and several small studies have reported benefits in angina patients, wrote Ling Zhao, PhD, of Chengdu (China) University of Traditional Chinese Medicine and colleagues.
In a study published in JAMA Internal Medicine, the researchers randomized patients aged 35-80 years with chronic stable angina into four groups: treatment on the disease-affected meridian (DAM), treatment on the nonaffected meridian (NAM), sham acupuncture (SA), and no acupuncture (wait list, or WL).
Chronic stable angina is defined by the American College of Cardiology and the American Heart Association as angina at least twice a week. Patients with other serious conditions including a history of MI, severe heart failure, valvular heart disease, and poorly controlled blood pressure or diabetes were excluded.
Each treatment group received three acupuncture sessions for 30 minutes each week for 4 weeks. Patients kept diaries of angina attacks and were assessed every 4 weeks for 16 weeks. After 16 weeks, the DAM patients had a significantly greater reduction in angina attacks, compared with the NAM group (4.1 fewer attacks), the SA group (5.2 fewer attacks), and the WL group (5.6 fewer attacks).
Overall, 16 patients reported adverse events related to acupuncture, including 5 cases of subcutaneous hemorrhage at the insertion point, 3 reports of tingling at the insertion point, and 8 reports of sleeplessness during the study period, but no patients discontinued the study because of these events. One patient in the WL group died of an acute MI and received no acupuncture treatment.
“We found that acupuncture on the DAM had superior and clinically relevant benefits in reducing angina frequency and pain intensity to a greater degree than acupuncture on a NAM, SA, or no acupuncture,” the researchers wrote. They found improvements in DAM patients on most metrics, including the Seattle Angina Questionnaire, compared with the other groups.
In addition, “compared with SA and no acupuncture, acupuncture on the DAM resulted in better regulation of anxiety and depression within the 12 weeks after treatment than at the end of the treatment period,” they wrote. “Acupuncture on the DAM causes autonomic remodeling by improving the balance between the vagus nerve and sympathetic nervous system during treatment.”
The findings were limited by several factors including the small sample size, potential performance bias based on variation in the acupuncturists’ experience, lack of analysis of doses of rescue medication, and lack of subgroup analysis, the researchers noted. However, the results are consistent with previous studies and support acupuncture as a potential adjunct treatment for patients with mild to moderate chronic angina.
The researchers had no financial conflicts to disclose. The study was funded by the National Natural Science Foundation of China and the State Key Program for Basic Research of China.