Symptoms during cancer pain treatment following WHO-guidelines: a longitudinal follow-up study of symptom prevalence, severity and etiology

Most patients with advanced cancer develop diverse symptoms that can limit the efficacy of pain treatment and undermine their quality of life. The pre sent study surveys symptom prevalence, etiology and severity in 593 cancer patients treated by a pain service. Non-opioid analgesics, opioids and adju vants were administered following the WHO-guidelines for cancer pain relief . Other symptoms were systematically treated by appropriate adjuvant drugs. Pain and symptom severity was measured daily by patient self-assessment; t he physicians of the pain service assessed symptom etiology and the severit y of confusion, coma and gastrointestinal obstruction at each visit. The pa tients were treated for an average period of 51 days. Efficacy of pain trea tment was good in 70%, satisfactory in 16% and inadequate in 14% of patient s. The initial treatment caused a significant reduction in the average numb er of symptoms from four to three. Prevalence and severity of anorexia, imp aired activity, confusion, mood changes, insomnia, constipation, dyspepsia, dyspnoea, coughing, dysphagia and urinary symptoms were significantly redu ced, those of sedation, other neuropsychiatric symptoms and dry mouth were significantly increased and those of coma, vertigo, diarrhea, nausea, vomit ing, intestinal obstruction, erythema, pruritus and sweating remained uncha nged. The most frequent symptoms were impaired activity (74% of days), mood chances (22%), constipation (23%), nausea (23%) and dry mouth (20%). The h ighest severity scores were associated with impaired activity, sedation, co ma, intestinal obstruction, dysphagia and urinary symptoms. Of all 23 sympt oms, only constipation, erythema and dry mouth were assessed as being most frequently caused by the analgesic regimen. In conclusion, the high prevale nce and severity of many symptoms in far advanced cancer can be reduced, if pain treatment is combined with systematic symptom control. Nevertheless, general, neuropsychiatric and gastrointestinal symptoms are experienced dur ing a major part of treatment time and pain relief was inadequate in 14% of patients. Cancer pain management has to be embedded in a frame of palliati ve care, taking all the possibilities of symptom management into considerat ion. (C) 2001 International Association for the Study of Pain. Published by Elsevier Science B.V. All rights reserved.