Correspondence
Injury Prevention
N Engl J Med 1998; 338:132-133January 8, 1998
- Article
To the Editor:
We enjoyed the excellent and timely review of injury prevention by Rivara et al. (Aug. 21 and Aug. 28 issues).1 We wish to comment on the role of automobile speeds and speed limits in increasing the toll of death and injuries in motor vehicle crashes.
Small increases in speed limits mean increases in actual traveling speeds, an increased crash fatality risk, and large rises in death tolls.2 A 10 percent increase in impact speed translates into a 40 percent rise in the case fatality risk among both restrained and unrestrained occupants.3 Crash, injury, and death tolls in the United States fell in the 1970s and have recently risen in proportion to the percent fall and rise in average speeds, to the first, second, and fourth powers, respectively. The case for a cause–effect relation between speed limits, speed, and death tolls comes from epidemiologic studies based on analytic time-series models.4 Raising the speed limits in Israel in 1993, from 90 to 100 km per hour (56 to 63 miles per hour), led to an 18 percent increase in road fatalities over a 2-year period, as compared with the preceding 10-year period.5 These findings were particularly noticeable in one-vehicle crashes, truck crashes, and crashes involving young and inebriated drivers.
Congress allowed each state to raise interurban highway speed limits in 1996. Preliminary data from the National Transportation Safety Board point to a rise in the death toll, mainly as a result of increases in the case fatality risk. After years in which the inexorable rise in road fatalities was curbed in the United States, 1996–97 marks a reversal of that trend, with over 44,000 road fatalities in 1996. Speed-associated crashes accounted for nearly 31 percent of the road-related death toll in the United States.6
These findings echo the results from other countries, including Australia, Denmark, Israel, and Sweden. The presumed benefits of reduced travel time at the higher speeds are achieved for many at a cost in terms of injury and death, and at an enormous cost to society. In order for injury-prevention programs to succeed and to have an impact on reducing the road-related death toll, we must start implementing speed restriction, particularly for truck drivers and younger drivers.
6 ReferencesPaul Barach, M.D., M.P.H.
Massachusetts General Hospital, Boston, MA 02114Eliahu Richter, M.D., M.P.H.
Hebrew University, Jerusalem 91120, Israel1
Rivara FP ,Grossman DC ,Cummings P . Injury prevention. N Engl J Med 1997;337:543-8, 613
Full Text | Web of Science | Medline2
Nilsson G. The effect of speed limits on traffic accidents in Sweden. VTI report no. 68. S-58101. Linkoping, Sweden: National Road and Traffic Institute, 1992:1-10.
3
Joksch HC . Velocity change and fatality risk in a crash -- a rule of thumb. Accid Anal Prev 1993;25:103-104
CrossRef | Web of Science | Medline4
Baum H ,Wells J ,Lund A . The fatality consequences of the 65 mph speed limit. J Safety Res 1991;22:171-177
CrossRef | Web of Science5
Barach P. The impact of raising the speed limits on interurban highways on accidents, deaths and injuries in Israel. (Master's thesis. Jerusalem: Hebrew University, 1996.)
6
Speeding. In: Traffic safety facts 1995. Washington, D.C.: Department of Transportation, 1995:1-2.
To the Editor:
In their important, timely review of injury prevention, Rivara et al. neglect to mention that the act of stopping smoking could prevent the many injuries, disasters, expenses, and illnesses that smoking causes1-3 or may cause.2-4
Smoking causes preventable fires,2 disasters,1,2 osteoporosis (and some resultant injuries), wound complications, bone nonunions,3 other injuries, and illnesses.2 Smoking caused over 1400 injury-related deaths and 430,000 illness-related deaths in 1988 in the United States alone. The 1400 injury-related deaths (about 1 percent of all deaths in the United States from injury) were all from fires. Injuries caused by explosions probably ignited by smoking are not counted in the U.S. tolls from smoking.2 One such explosion is the 1947 Texas City disaster, which was the worst industrial disaster in U.S. history. It killed about 600 people, injured another 3500, damaged nearly all Texas City homes and businesses, caused billions of dollars (in 1995 dollars) of destruction, and resulted in an unknown amount of health care and disability expenses.1
Smoking also causes nonfatal injuries. Cigarette lighters alone caused over 20,000 emergency room visits for nonfatal injuries in 1988 in the United States. Cigarette burns to the skin and eyes of children are also well-recognized problems.2
4 ReferencesBruce N. Leistikow, M.D.
University of California, Davis, Davis, CA 95616-83681
Stephens HW. The Texas City disaster, 1947. Austin: University of Texas Press, 1997:141.
2
Sacks JJ ,Nelson DE . Smoking and injuries: an overview. Prev Med 1994;23:515-520
CrossRef | Web of Science | Medline3
Kwiatkowski TC ,Hanley EN Jr ,Ramp WK . Cigarette smoking and its orthopedic consequences. Am J Orthop 1996;25:590-597
Medline4
Multiple Risk Factor Intervention Trial Research Group
CrossRef | Web of Science
To the Editor:
Rivara et al. committed an error of omission in their otherwise excellent synopsis of the importance of hip fractures and the methods available to prevent them. After presenting the data from a meta-analysis of hormone-replacement therapy and discussing the role of calcium and vitamin D supplements as well as thiazide diuretics, they conclude by stating that the “use of other drugs, such as calcitonin, fluoride, and etidronate, to increase bone density is still experimental but deserves further evaluation.” Not mentioned is alendronate, the one agent approved for the treatment of osteoporosis that has clearly demonstrated efficacy in prospective, randomized trials to prevent hip fractures in noninstitutionalized women with postmenopausal osteoporosis.1-3
3 ReferencesDavid B. Karpf, M.D.
16215 Rose Ave., Monte Sereno, CA 950301
Liberman UA ,Weiss SR ,Broll J , et al. Effect of oral alendronate on bone mineral density and the incidence of fractures in postmenopausal osteoporosis. N Engl J Med 1995;333:1437-1443
Full Text | Web of Science | Medline2
Black DM ,Cummings SR ,Karpf DB , et al. Randomised trial of effect of alendronate on risk of fracture in women with existing vertebral fractures. Lancet 1996;348:1535-1541
CrossRef | Web of Science | Medline3
Karpf DB ,Shapiro DR ,Seeman E , et al. Prevention of nonvertebral fractures by alendronate: a meta-analysis. JAMA 1997;277:1159-1164
CrossRef | Web of Science | Medline
Author/Editor Response
The authors reply:
To the Editor: We appreciate Karpf's bringing to our attention the randomized, controlled trials on the effect of alendronate in preventing fractures in women with postmenopausal osteoporosis. Alendronate in this group was associated with a 48 percent decrease in the risk of new vertebral fractures (95 percent confidence interval, 5 to 72 percent) in a randomized, controlled trial of 994 women1 and a 29 percent decrease in the risk of nonvertebral fractures (95 percent confidence interval, 1 to 50 percent) in a meta-analysis of four studies involving 1602 women.2
Leistikow underscores the association between smoking and burn injuries. We pointed out in our review that cigarettes are a major cause of residential fires.
Greater vehicle speed increases both the risk of a crash and the risk of death if a crash occurs, as pointed out by Barach and Richter. Several U.S. studies suggest that increases in legal speed limits have been associated with increased mortality due to crashes.3,4 In our article, we could address only a few aspects of crash prevention, and we emphasized areas in which practitioners might be able to change their patients' behavior, as in the use of restraints.
4 ReferencesFrederick P. Rivara, M.D., M.P.H.
David C. Grossman, M.D., M.P.H.
Peter Cummings, M.D., M.P.H.
Harborview Injury Prevention and Research Center, Seattle, WA 98104-24991
Liberman UA ,Weiss SR ,Broll J , et al. Effect of oral alendronate on bone mineral density and the incidence of fractures in postmenopausal osteoporosis. N Engl J Med 1995;333:1437-1443
Full Text | Web of Science | Medline2
Karpf DB ,Shapiro DR ,Seeman E , et al. Prevention of nonvertebral fractures by alendronate: a meta-analysis. JAMA 1997;277:1159-1164
CrossRef | Web of Science | Medline3
Gallaher MM ,Sewell CM ,Flint S , et al. Effects of the 65-mph speed limit on rural interstate fatalities in New Mexico. JAMA 1989;262:2243-2245
CrossRef | Web of Science | Medline4
Rock SM . Impact of the 65 mph speed limit on accidents, deaths, and injuries in Illinois. Accid Anal Prev 1995;27:207-214
CrossRef | Web of Science | Medline
