Article of the Month

Reasons for under-use of prescribed opioid medications by patients in pain

Lewis ET, Combs A, Trafton JA.

Pain Medicine 2010; 11 : 861-871

The fear of overuse, misuse, abuse and addiction in prescribing opioid analgesics in patients with chronic pain is one of the major causes of opioid phobia among physicians and the problems we observe with national regulatory policy regarding pain relief.

The data in the literature show that 2% of a random sample of adults in the United States report regular use of opioid medications. However, despite the increase in prescription use, the problem of uncontrolled pain persists.

Whilst great effort has focused on identifying risk factors for over-using opioids and developing screening tools, less attention has been given to under-use of prescribed opioids despite the evidence that under-use is substantially more frequent.

The authors considered the over-use of opioids while defining the patient s who under-used medication as those who take less than their prescribed dose and reported that resulting pain impaired their ability to engage in normal daily activities.

All patients who had received an outpatient prescription of opioid medication from the VA Palo Alto Health Care System (VGAPAHCS) during the previous 12 months were eligible. Data from electronic medical records revealed more than 9,000 eligible patients and 3,065 were randomly selected as candidates. Forty-four percent of the potential candidates were also invited to participate by their primary care providers.

Eighteen percent (227) of these patients responded. 36 did not complete the study because of an inability to remember their experiences with an opioid. Only 191 patients completed the study (92% male, 62.5 years old on average, 27% non-White). They had received an average of 7.2 opioid prescriptions (range 1-31 per participant in the previous year) compared with 6.5 prescription in the eligible population.

The first author interviewed 169 patients and the second author conducted 22 interviews consisting of 15 separate assessments. The authors used the questions in the Prescribing Drug Use Questionnaire (PDUQ) which is a 42-item screening tool to identify addiction to pain medication.

During the interviews, the authors recognized that while some subjects clearly described over-using opioids, others described various under-use behaviors related to their opioid medication.

Subjects who under-used opioids are those who:

• take less than the dosage allowed by their prescription,
• report inadequate pain relief , or
• report that pain impairs their normal daily activities.

These subjects do not take their opioids, or take them less frequently, or at lower doses, than prescribed even though they report pain alters their QoL.

Problematic under-use of medication was more common than over-use (20% vs 9%). A higher percentage of under-users were female and non-W hite and reported having more pain but no side effects. They avoided taking opioids even if they had received more than 5 prescriptions in the previous 12 months.

The explanations for under-use of opioids by the subjects were as follows:

1. to minimize the intake,
2. to decrease the adverse effects and addiction,
3. to make the regimen more acceptable,
4. to reduce financial burdens,
5. to use medication symptomatically. Under-users were likely to wait as long as possible prior to taking medication, and then only take it when pain was extreme or they needed sleep.
6. to use medication strategically in order to take part in social life,
7. to use supplements or alternatives to their medicine,
8. patients identified communication problems with doctors (it was reported that physicians do not listen very well to their pain problem),

9. the medication was ineffective (27% of under-user vs 11% of users),

10. pressure from family and friends to use the medicine.

Why I choose this article.

This study does not specifically consider cancer patients experiencing pain however it provides some interesting data.

• under-use of prescribed opioid medications is more frequent than over-use
• improved patient-physician communication, appropriate assessment of the intensity of pain as well as its causes (including an evaluation of “TOTAL PAIN”) will probably improve outcomes in the oncological and palliative care settings
• under-use of opioids may be one of the explanations of poor pain control notwithstanding an increase number of prescriptions
• physicians need to take the time necessary to communicate with patients and their families. This is an important way to understand not only the pain problem but the problems related to analgesic drug prescribing.

 Reviewed by Dr. Carla Ripamonti (Italy). Dr. Ripamonti is a member of the IAHPC Board and her bio may be viewed at http://www.hospicecare.com/Bio/c_ripamonti.htm