abilities [11,12]. Our data showing a more than tripled risk of
head/brain injury support this finding.
A well-designed analysis from Maryland found a similar
odds ratio (5.6) for any injury in riders under the influence of
alcohol, but the study specifically excluded enrollment at
night out of concern for the safety of researchers enrolling
controls  , although 2 prior reports found that nighttime
riders are more likely to be impaired [4,8]. These retro-
spective reports also found a strong correlation between
alcohol and bicycling injury. Another report from Sweden
using telephone interviews attempted to characterize alcohol
use and riders' environment in Goteborg, that nation's second
largest city (population 500 000) , but these data are
difficult to extrapolate to American cities because of likely
differences in riding and driving patterns. No detailed,
prospective report has bee n published fully describing
where alcohol-using bicyclists are likely to ride and thus
where interventions targeted at reducing drunken riding are
most likely to succeed.
From our data, a number of strong associations arise with
riders who use alcohol. Only 1 of the 40 riders wore a helmet.
Local laws require only riders younger than 18 years to wear
one, and Texas has no state law. Only 21 states and the
District of Columbia have state laws, all applying to minors
only, although there exists a patchwork of 186 local laws,
some applying to adults, in many states . (The Bicycle
Helmet Safety Institute publishes a yearly review of helmets
meeting impact safety criteria , and it identified the Bell
Citi model as one of the safest and best value.)
Impaired riders were less experienced by self report,
impervious to adverse road conditions and unlikely to have
medical insurance, leaving society to bear the financial
burden of their care. With rare exception, they rode in the
evening or at night on city streets with speed limits less than
45 mph. Under local laws, impaired cyclists can only be
arrested for public intoxication and not the more serious
charge of driving while intoxicated. Our data support a call
for national and/or state legislation specifically addressing
cycling while intoxicated and imposing much stronger
penalties for this hazardous activity. Although our data set
did not find significance in relative risk of cycling without
helmet (most likely due to small sample size), it did show a
trend consistent with previous studies that form an over-
whelming body of evidence that helmets prevent injuries
and save lives, and laws should be passed to encourage
cyclists to wear helmets.
Riders who use alcohol appear to exhibit predictable and
unsafe riding patterns in this mid-sized American city, and,
confirming prior reports, are much more likely to have head
or brain injury, lack medical insurance, and generate
increased hospital charges. Awareness of these interrelated
characteristics may lead to more successful interventions.
 National Safety Council. Injury facts. Washington (DC): National
Safety Council; 2008. p. 130.
 Baker SP, Li G, Fowler C, Dannenberg AL. Injuries to bicyclists: a
national perspective. Baltimore (Md): The Johns Hopkins Injury
Prevention Center; 1993.
 Kraus JF, Fife D, Conroy C. Incidence, severity and outcomes of brain
injuries involving bicycles. Am J Public Health 1986;77:76.
 Li G, Baker SP. Alcohol in fatally injured bicyclists. Accid Anal Prev
 Spaite DW, Criss EA, Weiss DJ, Valenzuela TD, Judkins D,
Meislin HW. A prospective investigation of the impact of alcohol
consumption on helmet use, injury severity, medical resource
utilization, and health care costs in bicycle-related trauma. J Trauma
 Frank E, Frankel P, Mullins RJ, Taylor N. Injuries resulting from
bicycle collisions. Acad Emerg Med 1995;2:200-3.
 Yelon JA, Harrigan N, Evans JT. Bicycle trauma: a five-year
experience. Am Surg 1995;61:202-5.
 Li G, Baker SP, Sterling S, et al. A comparative analysis of alcohol in
fatal and nonfatal bicycling injuries. Alcohol Clin Exp Res 1996;20:
 Olkkonen S, Honkanen R. The role of alcohol in nonfatal bicycle
injuries. Accid Anal Prev 1994;22:89-96.
 Anderssen A, Bukertorp O. Cycling and alcohol. Injury Int J Care
 Schewe G, Englert L, Ludwig O, et al. Untersuchungen über
Alkoholbedingte Leistungseinbuben bei Fahrrad- und Mofa-
Fahrren (Examining the influence of alcohol on the performance
of bicyclists and Mofa-riders). Beitr Gerichtl Med 1978;36:
 Schewe G, Knoss HP, Ludwig O, et al. Experimental studies on the
question of the marginal value of alcohol-induced unfitness to
operate a vehicle in the case of bicyclists. Blutalkohol 1984;21:
 Li G, Baker SP, Smialek J, et al. Use of alcohol as a risk factor for
bicycling injury. JAMA 2001;285:893-6.
 Bicycle Helmet Safety Institute. Helmet laws for bicycle riders: a
summary. BHSI, Retrieved from the Internet at www.helmets.org
(Sept. 1, 2008).
72 P. Crocker et al.