Cerebral effects of long-term oral opioids in cancer patients measured by continuous reaction time

Abstract

Cerebral function was studied in a group of 34 cancer patients being treated with stable doses of 30-920 mg morphine/24 h using measurement of continuous reaction time. Sedation visual analog scale, pain visual analog scale and time from last medication were registered. This group was compared to a group of 32 healthy controls taking no opioids. Small but statistically significant prolongations of continuous reaction time were seen in the opioid group. Analgesic dose and sedation visual analog scales were weakly positively correlated to continuous reaction time, but factors other than opioid treatment must influence cancer patients' performance of continuous reaction time.