Studies on acupuncture treatment of xerostomia

Abstract

Xerostomia (dry mouth) is most often associated with Sjögren's Syndrome (SS), medication, endocrinological disorders, or irradiation treatment to the head- and neck region. There is no effective treatment of xerostomia at the present. Only alleviating methods are used, such as saliva substitutes, saliva stimulating agents, chewing gum, pilocarpine, and electrical stimulation; however, these methods give only a short-term relief. Acupuncture, one of many methods of sensory stimulation, has been used to treat various diseases for over 3000 years.

Five studies were performed in order to elucidate the effects of acupuncture on xerostomic patients. In the first two studies the effects of acupuncture stimulation on 59 patients with xerostomia caused by irradiation, SS, hypothyroidism, Raynaud's disease, or unknown etiology were investigated. The results of these studies indicate that acupuncture may be a useful method of treatment for inflammation- and irradiation-induced xerostomia.

In the third study the effects of four different stimulatory modes of acupuncture on blood flux were investigated using Laser Doppler flowmetry. 21 patients with primary or secondary SS were treated with four different modes of acupuncture on different occasions: manual stimulation, low frequency (2 Hz) and high frequency (80 Hz) electrical stimulation, and with superficial needle insertion. The results show that the local blood flux in the skin of the cheek increased significantly (p<0.05) during acupuncture with low and high frequency electrical stimulation, and both during and after treatment using manual stimulation. The results of this study indicate that increases in the peripheral blood flux of xerostomic patients may be one of the underlying mechanisms of acupuncture, and that superficial acupuncture results in a change in blood flux, suggesting it should not be used as a placebo intervention.

The fourth study determined the prognostic value of a Pilocarpine Test, aimed at identifying xerostomic patients who may benefit from acupuncture treatment. The study included 32 patients with xerostomia caused by radiation treatment (n=21) or SS (n=11). Salivary secretion was determined before and after a Pilocarpine Test, and subsequently, all patients were given 24 acupuncture treatments and followed up at I and 6 months. The effects of acupuncture treatment on salivary flow rates (SFR) were compared to the results of the Pilocarpine Test. The Pilocarpine Test was found to have a high sensitivity (0.89) and a good positive predictive value (0.74) in identifying patients who may respond to acupuncture treatment of xerostomia.

The fifth study was a retrospective investigation, determining the long-term effects up to 3 years of acupuncture in 70 patients with xerostomia of different etiologies and the influence of additional treatment. This study shows that acupuncture treatment results in statistically significant improvements in SFR in patients with xerostomia up to 6 months.

The main findings of these five studies were: Acupuncture treatment can improve salivary flow rates in patients with xerostomia of different etiology. The Pilocarpine Test is a good prognostic tool for predicting if acupuncture treatment may successfully treat patients with xerostomia. It is suggested that patients should be treated with at least 24 initial sessions over a period of approximately four months. The results indicate that 10-12 additional treatments every year can maintain, and in some cases, give further improvements. No serious negative side effects were observed.

Acupuncture can be recommended as a valuable treatment method with long-term effect for patients with xerostomia.