Abstract
Dear Editor:
The World Health Organization (WHO) three-step analgesic ladder is used as a guideline for the treatment of cancer pain; however, many patients do not experience adequate pain relief. 1 A few studies have proposed alternative therapies to the WHO ladder. 2 Some authors criticize the restriction of potent opioid use to the third step of the ladder. 3 These controversies indicate the need for further investigation. The aim of this study was to determine whether the use of morphine in the first step of the ladder can increase relief of cancer pain.
After approval of the ethics committee and signing the consent, a prospective randomized study was performed in patients ≥18 years with moderate pain intensity. Group 1 (G1) patients were treated according to the guidelines of the WHO analgesic ladder starting at the first step, with paracetamol 1g each 6 hours; in the second step, codeine 30 mg each 4 hours, maximum dose 360 mg/day; and morphine 10 mg each 4 hours in the third step. Patients in group 2 (G2) started with morphine 10 mg each 4 hours. Adjuvant drugs have been associated when indicated.
Evaluated were pain intensity (every 2 weeks) using the visual analog scale (VAS); quality of life (every 4 weeks), using the brief WHO quality-of-life questionnaire; satisfaction with treatment; physical capacity, using the index of the Eastern Cooperative Oncology Group (ECOG); and the need for additional analgesics. Adverse effects were recorded. Follow-up monitoring continued for three months.
The program BioEstat 2.0 was used to calculate the sample size. Statistical analysis was performed using GraphPad Prism® program for statistical analysis. T-tests were used to compare age, weight, and height across groups; Pearson's chi-squared tests were used for patient satisfaction, need for complementation, and adverse effects; and Mann-Whitney U tests were used for pain intensity, quality of life, and physical capacity.
Sixty patients were enrolled in the study, and 24 G1 patients and 29 G2 patients completed all three months of follow-up. The groups had similar demographic data.
There was no difference between groups in pain intensity scores (Table 1). Also there was no difference in need for supplementation of morphine, quality of life measures, physical capacity, or satisfaction with treatment. Statistically significant differences between groups were observed at the second visit in frequency of nausea, constipation, dizziness, and somnolence. A statistically significant group difference in somnolence was also observed at the third visit.
G1, with WHO; G2, without WHO; Student's t-test.
30; b29; c28; d27; e24; f23.
In this study a reduction in pain intensity was observed in both groups, suggesting that both techniques were effective. In another study patients who received potent opioids achieved better pain control and were more satisfied than those in the conventional group, but experienced more adverse effects. 2 There was a higher incidence of side effects when morphine was administered first.
We conclude that the two approaches to treating pain in patients with advanced cancer are comparable, with the exception that patients who are given morphine as a first-line treatment experience more side effects early in treatment.