Gambling and subsequent road traffic injuries: a longitudinal cohort analysis

Background — To compare the risks of a road traffic injury (RTI) crash among adults who were involved in high-risk gambling and those who did not gamble.

Methods — We conducted a linked longitudinal cohort analysis of adult persons in large population survey conducted during 2007 and 2008 in Ontario, Canada. We used responses to Problem Gambling Severity Index to distinguish persons as nongamblers, no-risk, low-risk, or high-risk gamblers. All persons were subsequently monitored for a subsequent RTI crash as a driver, pedestrian, or bicyclist up to March 31, 2014, through health insurance databases. We estimated relative risks as rate ratios (RRs) with 95% confidence intervals (95% CIs).

Results — In all, 30,652 adults were included, of whom 52% self-identified as gamblers, including 49% as no-risk gamblers, 2% as low-risk gamblers, and 1% as high-risk gamblers. During a median follow-up period of 6.8 years, 708 participants (2%) were involved in 821 RTI crashes. The absolute risks of an RTI were 6.4 per 1000 person-years (95% CI 3.7-10.4) in high-risk gamblers and 3.6 per 1000 person-years (95% CI 3.2-4.0) in nongamblers. The relative risks for RTI crashes were significantly higher in high-risk gamblers than in nongamblers (adjusted RR 1.68, 95% CI 1.03-2.76). The risks for RTI crashes as a driver were augmented in high-risk gamblers than in nongamblers (RR 1.97, 95% CI 1.13-3.43).

Conclusions — We found an increased risk of an RTI crash among drivers who self-identified as high-risk gamblers. Further research exploring the underlying mechanisms of these associations might interest health professionals to monitor RTI risks in adults involved in high-risk gambling.