Assessing cognition and psychomotor function under long-term treatment with controlled release oxycodone in...

The therapeutic use of opioids can be associated with altered cognition and impaired psychomotor function. Several studies have demonstrated the impact of opioid therapy on psychomotor performance and cognition, but no data exist about the effect of long-term treatment with controlled release oxycodone (CRO) on driving ability.

Thirty patients suffering from chronic non-cancer pain who had been treated with stable doses of CRO where included in a prospective trial and compared with 90 healthy volunteers (matched pairs). A computerized test battery that was developed to assess the driving ability of traffic delinquents in Germany was employed. Attention reaction, visual orientation, motor coordination and vigilance were evaluated. The data from a total of 11 parameters were assessed and for each test a relevant score was defined. As the primary endpoint the sum score of the three relevant scores was determined. A weaker statistical means to assess the patients' performance is to compare the test results with an age-independent control group. Individuals performing worse than the 16th percentile of this control group are considered to be unable to drive according to German legislation.

Significant non-inferiority could not be demonstrated for the primary endpoint. However, driving ability as defined as a result above the 16th percentile did not differ significantly between the patients receiving CRO and the age-independent control group.

The use of CRO does not prohibit driving, but individual assessment is necessary.