June 2006

Dear Readers Here's the Article for this Month:

A validation study of the WHO analgesic ladder:
a two-step vs three-step strategy

Author(s): Maltoni M, Scarpi E, Modonesi C, et al.

Journal: Supportive Care Cancer 2005; 13: 888-894

For the treatment of cancer pain, the World Health Organization (WHO) guidelines propose a 3-step analgesic ladder made up of NSAIDs ± adjuvant drugs (1 st step); weak opioids for mild-moderate pain ± NSAIDs ± adjuvant drugs (2 nd step), and strong opioids for moderate-severe pain ± NSAIDs ± adjuvant drugs (3 rd step).

The role and the utility of the 2 nd step of this pharmacological ladder has been debated by various authors. Moreover, in routine clinical practice, the question that arises is what really changes regarding the analgesic and the tolerable efficacy of weak opioids, or low-dose strong opioids, if one or the other is used even for mild-moderate pain?

The authors carried out a randomized prospective study with the aim to evaluate the efficacy and tolerability of two different therapeutic approaches: one indicated by the WHO guidelines (group A) using step II, and another where the patients, after ineffective therapy with NSAIDs, were treated with strong opioids (group B) without passing through step II.

Patients had to be opioid naïve and experience mild-moderate pain. Pain intensity was assessed by means of 4 questions (the worst, the least, the average pain during the previous 24 hours and actual pain at the moment of the interview) selected from the validated Italian version of the Brief Pain Inventory.

Other symptoms (gastrointestinal, pruritus, sweating, neuropsychiatric, and urinary) were assessed on a 5 point verbal scale (from none to very severe). The patients’ satisfaction was also assessed with a 5 point scale (from very satisfied to very dissatisfied).

Over 24 months, 24 patients in the group A (mean age 65) and 30 in the group B (mean age 69) who were undergoing treatment with NSAIDs (most of them dissatisfied or very dissatisfied with this therapy), were enrolled in the study. At baseline, the intensity of pain reported was mild (12.5% in group A, 23.3% in group B); moderate (66.7% (A) and 63.4% (B) and severe (20.8% (A) and 13.3% (B). The intensity of other symptoms and the use of adjuvant drugs was similar between the two groups.

The patients’ assessment was continued for 42 days after randomization. The results of the study showed that: 1) in group A patients the intensity of the worst pain ≥ 5 was present in 28.6% of days vs 22.8% of days in group B (p< 0.001) and was ≥ 7 in 11.2% of days in Group A vs 8.6% of days in group B (p=0.023); 2) in group A the patients were dissatisfied (11.6%), or very dissatisfied (12.1%) in 10.4% of treatment days whereas in the group B, patients were less dissatisfied (7.9%) or very dissatisfied (0.6%); 3) in group A severe anorexia and constipation were present in 7.0% and in 5.9% of the days respectively vs 13.2% and 17.7% of treatment days in group B respectively. However, constipation prophylaxis was used less in group B pateints.

Why I chose this article

The usefulness of step II in the WHO analgesic ladder has been questioned by several clinicians involved in the treatment of cancer pain. This study shows that opioid naive patients treated with strong opioids report a pain intensity less than those who were treated with “weak opioids” (step II). Further studies should be carried out on this topic because step II drugs are sometimes expensive and not available worldwide.

Regards,

Carla Ripamonti, MD
Member of the Board of Directors, IAHPC

Please visit the following link to read past Articles Of The Month:
http://www.hospicecare.com/AOM/