Cancer Advances: Poor Adherence to Pain Medication Results in Ineffective Pain Management

From the December 1, 2001 issue of the Journal of Clinical Oncology.

Cancer patients are not achieving adequate pain relief because many do not adhere to their pain medication regimens and do not receive adequate pain medication prescriptions, a new study finds. The study was conducted by researchers at the Schools of Nursing, Medicine, and Pharmacy at the University of California at San Francisco.

According to lead author Christine Miaskowski, RN, PhD, Professor of Chair of the Department of Physiological Nursing at UCSF, side effects caused by frequently prescribed analgesics were the main reason cancer patients cited for not taking their pain medication as prescribed. "Patients told us that they would rather be in severe pain than deal with constipation. This is unfortunate, because constipation - the major side effect of opioid analgesics such as morphine - can be treated effectively."

The randomized six-week study included 65 adult oncology patients with chronic pain and evidence of bone metastases (cancer in the bone that has spread from another part of the body). On a daily basis, patients rated their level of pain intensity and recorded their pain medication intake. Adherence rates - what the patient was taking versus what the physician prescribed - for opioid pain medicines (such as morphine) prescribed on an around-the-clock and an as-needed basis were calculated weekly.

Overall adherence rates ranged from 84.5 to 90.8 percent for around-the-clock opioid pain medicines and 22.2 to 26.6 percent for as-needed pain medicines. According to Dr. Miaskowski, the difference between around-the-clock and as-needed adherence rates can be attributed to the way prescriptions were written. "If patients are told to take a drug around-the-clock, rather than as-needed, they are more likely to stick with the regimen. This has been shown in other studies."

In addition to side effects from opioid analgesics, inadequate pain prescriptions also contributed to patients' inability to achieve adequate pain relief.

Federal guidelines recommend that all cancer patients with chronic pain be prescribed an around-the-clock analgesic regimen for chronic pain, as well as a short-acting supplement for breakthrough pain. However, not all patients received both types of medication. In the study, 13.9 percent of patients were prescribed opioid analgesics on an around-the-clock basis, 56.9 percent were prescribed opioid analgesics on an as-needed basis, and 29.2 percent were prescribed both around-the-clock and as-needed analgesics.

According to an accompanying editorial in the Journal of Clinical Oncology by Jamie von Roenn, MD, Professor of Medicine at Northwestern University, "Lack of adequate knowledge or assessment of pain management by physicians is suggested by the pattern of analgesic prescriptions. Effective pain management requires repeated assessment and adjustments in dosage."

In an effort to improve physicians' knowledge of pain management, medical societies and universities have begun to integrate pain and symptom management into their educational activities.

What does this mean for patients?

According to the study, the main reason cancer patients did not achieve adequate pain relief is because they did not follow the pain medication prescriptions written by their doctors, citing side effects caused by the pain medication. The study also showed that patients who were given an around-the-clock pain medication were more likely to take their pain medication as prescribed.

To maximize pain relief, cancer patients should talk to their doctor about their pain and how to manage side effects. It's important for patients to tell their doctor whether the pain medication is or is not working, because doctors can often adjust the prescription to make it more effective.