Constipation caused by opioids treated with MTX
Source: Thomas J, Karver S, and Cooney GA, et al. Methylnaltrexone for opioid-induced constipation in advanced illness. N Engl J Med. 2008; 358:2,332-2,343.
In the adverse effects induced by opioid therapy, constipation is singular in its persistence. Opioid-induced bowel dysfunction (OBD) is thought to result primarily from action of opioids upon the mu receptor in the colonic myenteric plexus, which results in lack of contractility of the longitudinal muscle fibers, and hence a loss of peristalsis.
Traditional laxative tools for constipation generally are employed with some success. Bulk forming laxatives (for example, fiber) should be avoided in OBD because they actually might worsen symptoms or even lead to full obstruction in a non-motile colon.
Methylnaltrexone (MTX) is a mu-receptor antagonist which, because it is a quaternary amine compound, does not induce withdrawal symptoms in persons on chronic opioid therapy. Small pilot trials have supported the utility of oral and parenteral MTX for prompt relief of constipation.
Thomas, et al studied a population of subjects on opioid therapy (n = 133) who had not achieved relief of constipation with "traditional" laxatives. MTX subcutaneous was administered every other day for two weeks. Within four hours of the first dose, almost half of subjects had a spontaneous bowel movement (i.e., without the use of a "rescue" laxative). Pain scores were not adversely affected, and there were no signs of opioid withdrawal. No serious adverse events attributable to MTX were seen.
Poor have greater risk of dying after cancer
A new study looking at the survival and stages of cancer has found that people living in poor neighborhoods have a greater risk of dying after cancer than people with higher socioeconomic status.1
"These patients are generally diagnosed later than others and were less likely to get state-of-the-art cancer care," said Tim Byers, MD, MPH, lead author, deputy director of the University of Colorado Cancer Center in Aurora and a professor of preventive medicine and biometrics at the University of Colorado Denver. "Being poor increases your chance of dying from cancer," Byers says.
Researchers examined medical records of 13,598 patients diagnosed with certain cancers in 1997 in seven states. The study included 4,844 women with breast cancer, 4,332 men with prostate cancer, and 4,422 men and women with colorectal cancer living in California, Colorado, Illinois, Louisiana, New York, Rhode Island, and South Carolina. The researchers followed up with patients five years later to find out their cancer outcomes.
The study was commissioned by the Centers for Disease Control and Prevention to ascertain how socioeconomic status (SES) affected cancer mortality. The purpose is to better define strategies "to eliminate the unequal burden of cancer by race and ethnicity in the United States."
Reference:
1. Byers TE, Wolf HJ, Bauer KR, et al. The impact of socioeconomic status on survival after cancer in the United States: finding from the National Program of Cancer Registries. Cancer 2008. DOI: 10.1002/cncr.23567. Accessed at www3.interscience.wiley.com/journal/120195068/abstract.
Many cancer patients need better pain management
Pain is one of the most common symptoms of cancer patients, yet many of them don't receive adequate therapy for the pain caused by their disease or treatments, according to a study in a recent issue of the International Journal of Radiation Oncology*Biology*Physics, the official journal of the American Society for Therapeutic Radiology and Oncology.1
For cancer patients, pain can come from the cancer itself, chronic inflammatory changes, or infections. Standard cancer treatments, such as surgery, chemotherapy, and radiotherapy, also can cause pain, but despite its common occurrence, pain is a frequent source of patient anxiety due to improper management.
Researchers at the University of Pennsylvania Department of Radiation Oncology in Philadelphia and the Radiation Oncology Branch of the National Cancer Institute (NCI) in Bethesda, MD, sought to determine the primary reasons that patients fail to receive optimal pain therapy. Between November 2005 and April 2006, 106 radiation therapy patients responded to an Internet-based questionnaire that evaluated their medication use, pain control, and attitudes toward pain medication, including prescription and over-the-counter pain medications. Fifty-eight percent reported pain from their cancer treatment, and 46% of patients reported pain directly from their cancer, yet 80% of those patients said that they did not use medication to manage their pain.
Most patients said the primary reason they did not take pain medication was because their health care provider did not recommend it. This reason was followed by a fear of addiction or dependence and the inability to pay. Some patients also reported using alternative therapies for pain relief, including physical therapy, massage, and acupuncture. "To eliminate barriers to optimal pain management for cancer patients, health care providers should talk with their patients about pain symptoms and pain medications," says Charles Simone, MD, lead author of the study and a resident at the NCI Radiation Oncology Branch. "At our institution we have taken these steps by transitioning to an electronic medical record system that has been designed to require an evaluation and documentation of patient pain levels and pain medication responses by health care providers at each patient encounter."
Reference
1. Simone CB II, Vapiwala N, Hampshire MK, et al. Internet-based survey evaluating use of pain medications and attitudes of radiation oncology patients toward pain intervention. Int J Radiation Oncology Biol Phys 2008; 72: 127-133.
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