Effect of Press Needles on Swallowing Reflex in Older Adults with Cerebrovascular Disease: A Randomized Double‐Blind Controlled Trial (2014)

To the Editor: The global population is aging.1 Pneumonia is a leading cause of death in elderly adults, especially those with dysphasia and microaspiration.2 Because aspiration pneumonia is related to impairment of the swallowing and cough reflex,3 the development of preventive strategies is needed to improve such protective reflexes to reduce the incidence of pneumonia in older people. In Japan, pneumonia is the third leading cause of death.4 It was previously reported that acupuzncture at two points on the legs (ST36 and KI3) improved the swallowing reflex after stroke5 and reduced pharyngeal retention and aspiration.6 To investigate the effectiveness of acupuncture with press needles in improving the swallowing reflex in elderly adults with cerebrovascular disease, a three-arm randomized double-blind controlled multicenter trial was conducted by incorporating sham patches and sham points. Individuals aged 65 and older who had had a stroke and had dysphasia were recruited consecutively from two hospitals and two nursing homes in Sendai, Japan. The purpose and design of the study were explained to each individual, and informed consent was obtained. The Tohoku University ethics committee approved the study protocol. Twenty-nine individuals (10 men, 19 women; mean age ± SD 82.2 ± 7.1) were recruited and assigned randomly to three groups: group 1, press needles (Pyonex; Seirin Corporation, Shizuoka, Japan) on the ST36 and KI3; group 2, sham patches on the acupuncture points; and group 3, press needles on sham points. The needles were 0.2 mm in diameter and 0.6 mm long. The design of the sham patch was identical to that of the press needle except most of the needle had been cut off, so that only the head of the needle remained in the resin. Patches were applied and changed every day for 4 weeks. Latent time of swallowing reflex (LTSR), plasma substance P (SP), Barthel Index, Mini-Mental State Examination, and days of fever were measured at baseline and 4 weeks later. Table 1 shows the outcomes of this study. The primary outcome was change in LTSR. A statistically significant shortening of LTSR was evident in Group 1 (6.9 ± 2.3 vs 2.5 ± 0.3 seconds, P = .005), whereas no statistically significant difference was observed in the other two groups. There was a significant difference between the three groups in change in LTSR (P = .009). Change in LTSR in Group 1 was significantly different from that in Group 2 (P = .008) but not Group 3 (P > .99). There was a significant difference in LTSR at day 28 between Groups 1 and 2 (P = .001), but no significant difference between Groups 1 and 3 (P = .51). Plasma SP did not change significantly during the study in any group, and no differences in secondary outcomes were observed in any group between baseline and Day 28. Peripheral blood tests were performed to assess inflammatory and nutritional status. No statistically significant differences were observed in white blood cell count, C-reactive protein, total protein, albumin, or total cholesterol between baseline and Day 28. There were no significant differences in any parameters. Neither press needle nor sham needle treatment caused any side effects. Attachment of press needles at the two leg acupuncture points improved the swallowing reflex of elderly adults with cerebrovascular disease. Lack of a significant difference between acupuncture points and sham points indicates that the attachment of the fine needle itself has some effect on the swallowing reflex. Even if the press needles are placed at positions that deviate from the acupoints (e.g., sham points in this study), LTSR may improve, which is clinically convenient. This type of acupuncture may become a new adjuvant method for the prevention and treatment of pneumonia in elderly adults. The limitations of the present study were the small sample size and short follow-up time. In addition, only Group 3 included participants with extremely poor LTSR at baseline, which could have been why there was no difference between Groups 1 and 3 in LTSR at Day 28. Further studies are required to investigate the effect of the press needle on swallowing function. This clinical study was registered in UMIN Clinical Trials Registry. ID: UMIN000002133. The authors wish to thank Dr. Yoichi Kosaka, Hikarigaoka Spellman Hospital, Sendai, Japan, who recruited some of participants. Conflict of Interest: We declare that we have no conflicts of interest. This work was supported by Grant-in-Aid for Scientific Research from Japan Society for the Promotion of Science (Grant No. 22790608). Author Contributions: Kikuchi A. was the study chair and wrote the first draft of the paper. Seki T. contributed to study design and interpretation. Takayama S., Iwasaki K., and Yaegashi N. commented on the report. Ishizuka S. contributed to recruitment of participants. All authors contributed to review and approved the final draft of this paper. The corresponding author had full access to all the data in the study and had final responsibility for the decision to submit for publication. Sponsor's Role: The study sponsor had no role in the study design; in the collection, analysis, or interpretation of data; in the writing of the report; or in the decision to submit the paper for publication.