Nerve Stimulation Therapy May Alleviate Opioid-Induced Constipation in Patients With Cancer

Transcutaneous electrical nerve stimulation (TENS) therapy may be effective in the alleviation of opioid-induced constipation (OIC) and can improve the quality of life of patients with cancer receiving palliative care, according to study results published in Evidence-Based Complementary and Alternative Medicine.

Opioid-induced constipation is highly prevalent among patients with advanced cancer, but there continues to be limited evidence on the effects of TENS therapy in this population. In this study, researchers conducted a systematic review and meta-analysis using studies published across Embase, Cochrane, China National Knowledge Infrastructure, Chinese Biomedical, and Wanfang databases.

The researchers reviewed randomized controlled trials, studies that included patients diagnosed with both cancer and OIC, studies that described opioid dosages, those that compared treatment with and without TENS, those that included data on constipation, and those that followed a double-blind and open-label trial design. Overall, 180 articles were identified, of which 9 met inclusion criteria.

Primary study outcomes included incidence rates of OIC or rates of treatment effectiveness. Secondary outcomes were quality of life scores, incidence of adverse reactions, and relevant elements of the bias risk assessment.

Seven studies (n=809) indicated that TENS therapy vs control significantly reduced the incidence rate of OIC (pooled odds ratio [OR], 0.66; 95% CI, 0.53-0.82; P <.01). However, in 2 studies (n=449), TENS was not statistically significantly effective in treating OIC compared with control (OR, 1.08; P =.07).

Furthermore, in the 2 studies, researchers noted that TENS therapy vs control significantly increased the quality of life of patients with cancer receiving palliative care (OR, -1.91; 95% CI, -2.54 to -1.29; P <.01).

The researchers noted the small sample size present in some of the included studies, potential nonadherence to demographic and clinical control measures, as well as the lack of standardized protocol for TENS treatment as some of the limitations of the study.

“TENS can potentially treat OIC, but the evidence of its efficacy is limited,” the study authors wrote. However, “TENS can be combined with other therapies to provide complete relief of OIC,” they concluded.