Relationship between retinal nerve fiber layer thickness and driving ability in patients with human immunodeficiency virus infection.

BACKGROUND

The aim of this work is to study the possible association between retinal nerve fiber layer (NFL) thickness and driving ability.

METHODS

Thirty-eight drivers including 22 HIV-positive (HIV+) and 16 age-matched HIV-negative controls participants underwent a full ophthalmologic evaluation, including assessment of retinal NFL thickness. In the undilated state with standard optical correction and under standard illumination they also completed a computer-based, wide field-of-view driving simulation in which they were to obey traffic laws, engage in crash avoidance, and pass slower automobiles. Crashes, speeding and traffic light tickets, and off-road excursions contributed to a weighted score of driving errors.

RESULTS

HIV-seropositive participants had a significantly higher weighted error score than control participants (18.4 [9.2] vs. 11.1 [4.5], p = 0.006). NFL thickness was significantly correlated with driving errors (r = -0.51, p = 0.025); there was a trend for participants with a CD4 nadir <100 to have more errors than those with a nadir >100 (29.7 [13.2] vs. 19.3 [8.4], p = 0.056). The highest number of driving errors occurred in individuals with both CD4 <100 and NFL thickness <80.

CONCLUSIONS

Driving ability may be impacted by reductions in retinal nerve fiber layer thickness. Physicians should consider the potential impact that more complex ophthalmologic conditions in HIV-infected patients may have on driving performance.