NEW YORK (Reuters Health) - It is commonly believed that older patients who are given opioids for cancer pain are more susceptible than younger patients to adverse effects when doses of painkillers are increased to deal with worsening pain. However, Italian researchers now report that this is not the case.

Until now, "no data regarding the need for opioid escalation in patients already receiving opioids for the management of chronic pain are available," Dr. Sebastiano Mercadante, at La Maddalena Clinic for Cancer in Palermo, and colleagues write in the Journal of Pain and Symptom Management.

They therefore studied 100 patients already receiving opioids for cancer pain who required an increase in dose. The subjects were also divided into three age groups: younger than 65 years (group 1), 65 to 74 years (group 2), and 75 years or older (group 3).

The average dose of opioids needed at first to control pain decreased successively with increasing age. In group 1, it was the equivalent of 175 milligrams (mg) of oral morphine, in group 2 it was 159 mg, and in the oldest group, 44 mg.

When the doses were increased upward to control pain, the average doses in the three age-groups were stabilized at 270 mg, 173 mg, and 86 mg, respectively.

While older patients needed lower opioid doses overall, they tolerated an increase in dose as well as younger patients. Older patients did experience worse distress while the dose was being adjusted, but this improved after the stable dose was reached.

The investigators note that these findings "should be interpreted with caution" because of the small number (10) of patients older than 75 years in the study.

Nonetheless, they suggest that the fear of a higher risk of adverse effects in elderly patients is unwarranted and may lead to undertreatment of pain.