Specific problems: Alcohol and motor vehicles

Transcription

1 Specific problems: Alcohol and motor vehicles Vilma Leyton Julio de Carvalho Ponce Gabriel Andreuccetti INTRODUCTION Alcohol is a narcotic psychoactive substance that depresses the central nervous system, alters perception and behavior, and may increase aggressiveness and distract attention. It has also been known to cause dependence and other harmful effects to an individual s health and wellness. There are an estimated 2 billion consumers of alcoholic beverages in the world, which is approximately one third of the world population. The World Health Organization (WHO) defines a dose of alcohol as equivalent to 14 g of ethanol. This is the quantity of alcohol found in a can of beer (350 ml), a glass of wine (140 ml), or a dose of hard liquor (35 ml). The term intoxicated or drunk is used when there are concentrations of alcohol in the blood. One dose of an alcoholic beverage can result in a blood alcohol concentration (BAC) of 0.2 g/l in the blood stream of a man who weighs around 70 kg. In a woman who weighs around 60 kg, the consumption of a dose of alcohol could raise her blood alcohol content to 0.3 g/l. The maximum levels of alcohol content in the blood stream occurs generally half an hour after an alcoholic drink has been consumed and this can vary between populations. 1,2

2 Alcohol and its consequences: dealing with multiple concepts The ingestion of small quantities of alcohol can provoke alterations in behavior and cognitive faculties. Some individuals with a low tolerance for alcohol may show signs and symptoms of intoxication incompatible with the act of driving. 1,3 The principal effects of alcohol intoxication or drunkenness are expressed in Table 1. Table 1 Drunkenness and its corresponding effects Blood alcohol concentration (g/l) Effects 0.1 to 0.3 Relaxation of muscles A euphoric sense of well being and a feeling of relaxation Diminished timidity Vision and motor control are altered 0.4 to 0.6 Tachycardia of the heart is present and breathing pattern is increased Diminished brain activity Divided attention causes difficulty in information processing and attention span is also diminished Diminished inhibitions Increased relaxation of body 0.6 to 1 Increased anxiety and depressive symptoms Decrease in attention span, reaction time is slow and problems in motor coordination and muscle control appear Diminished capacity to make decisions 1 to 1.5 Slower reaction time Difficulty maintaining balance and vision becomes blurred Speech is effected and becomes slower 1.6 to 2.9 Extreme inability to respond to exterior stimulus Problems in motor control (falls and lack of motor control) 3 to 3.9 Fainting spells Anesthetization (comparable to that used in surgery) Stupor) 4 and above Respiratory difficulties Death Source: Global Road Safety Partnership, There are many variables among people who drink, in the absorption, metabolism, and elimination of ethanol from the organism. Factors that can significantly alter these parameters are listed below: 164

3 Specific problems: Alcohol and motor vehicles state of diet; gastric evacuation rate; composition of meal; type and dose of alcoholic beverage; body water content; gender; age; circulatory system and hepatic conditions; liver mass; genetic factors; alcoholic consumption pattern; interaction with medication and other drugs; state of general health. Traffic accidents are one of the main public health concerns of Brazil, and are ranked tenth as causes of deaths in Brazil and ninth as causes of death in the world. The total sum of deaths caused by traffic accidents in the world is 1.2 million and from 20 to 50 million are injured per year. These high numbers occur principally in countries of low or medium income, 2,4 and are costly for to public health services. In developing countries, the cost of traffic accidents can reach up to 2% of Gross National Product (GNP). If this tendency remains unchanged, and if in the next decades the number of traffic accidents will continue to increase it will remain one of the prime health concerns of the vulnerable populations of developing countries. In the United States, every year half a million lives are lost to traffic accidents related to alcohol consumption by the driver and drunk driving is a major concern of the American government. 4 Measures to protect passengers and drivers such as the obligatory use of seat belts, child safety harnesses, and helmets reduce the number of injuries sustained in accidents. The establishment of speed limits, the use of breath analyzers to ascertain BAC, the manufacturing of safer vehicles as well as the improvement of 165

4 Alcohol and its consequences: dealing with multiple concepts roads and highways are fundamental measures that have been adopted in order to reduce the number of deaths on roads and highways throughout the world. 3 Nowadays a global tendency to lower the maximum level of alcohol in the blood allowed for drivers has been considered. The United States, through legal and fiscal sanctions in the granting of funds for road improvement and the building of new highways, has motivated some states to lower their maximum limit from 1 g/l to 0.8 g/l. There is also a public movement pressuring the government to lower the maximum limit to 0.5 g/l. Countries such as Sweden and Norway, pioneers in traffic safety, have already adopted a limit of 0.2 g/l2 which is considered a low rate. The establishment of BAC limits for safer driving has stirred numerous debates. Studies though, indicate that a concentration of alcohol as little as 0.2 g/l can cause detectable alterations in divided attention, vision, and tracking tests. At 0.5 g/l, the risk of causing an accident while driving is increased and there is a clear reduction in simple and complex reaction times, especially during divided attention and information processing tasks. From this level to higher levels of BAC, automatic functions (e.g. driving) suffer dramatic alterations. 1,3 Considering only urban areas, traffic accidents cost Brazilian society R$5.3 billion in 2001, and further R$24.6 billion if accidents on state and federal highways are considered. 5 In 2002, the United States spent $230.6 billion US in traffic accident-related costs. It is estimated that 22% of these expenses ($51 billion US) are related to accidents resulting from alcohol consumption. When only fatal accidents are considered, alcohol is responsible for 46% of what the American government had to spend on traffic accidents that year. 6 ALCOHOL AND ACCIDENT RISKS Alcohol is recognized as one of the main causes of traffic accidents, since it affects important bodily functions needed to operate a vehicle, such as vision and reaction time, as well as behavioral factors that stimulate the taking of risks: running red lights, lack of seat belt use, and driving at high speeds. Motorcyclists 166

5 Specific problems: Alcohol and motor vehicles with a BAC higher than 0.5 g/l are more likely to ride without a helmet than sober motorcyclists. 7 Alcohol is responsible for the greatest number of traffic accidents, and is more prevalent than the number of accidents caused by illicit drugs consumption. 8 Epidemiological studies show a common profile of accident victims found in diverse communities. Most victims of traffic accidents related to alcohol use are young, economically active males. In cases where alcohol was involved, the chances of a victim being involved in a traffic accident is 4.9% greater than the chance of being involved in another type of accident. 9 According to studies about accidents involving only one vehicle, drivers who present blood alcohol concentrations from 0.2 g/l to 0.5 g/l have 2.5 to 4.6 times greater of a chance to die due to vehicular accident than a sober driver, depending on age, since younger drivers take more risks.1 For blood alcohol contents from 0.5 g/l to 0.8 g/l, the risk factor rises 6 to 17 times, and for even higher BACs the risk factors of dying from an automobile accident may vary from 11 to 15,560 times greater. 1 These numbers indicate that abusive alcohol use while driving increase the risk of getting involved in a fatal accident. Automobile collisions resulting in death are more common when the driver is under the influence of alcohol. Among collisions involving alcohol (defined as those in which at least one driver presented a BAC higher than 0,1 g/l) 4% resulted in death and 42% resulted in injuries. Among the collisions where alcohol was not the cause, only 0.6% resulted in one or more victims dying and 31% involved injuries. Studies in the United States show that 44% of the victims that died in automobile accidents where alcohol was involved were not driving at the time of the accident, 7% of the victims were drivers of other vehicles involved in the accident, 22% of the victims were passengers, 13% were pedestrians, and 2% were cyclists. 10 In countries of low and medium incomes there is a stronger association in the occurrence of traffic fatalities and alcohol use while driving. In these countries the percentage of drunk driving varies from 33% to 69%. In countries where incomes are higher, this percentage is approximately 20%. 2 This percentage, 167

6 Alcohol and its consequences: dealing with multiple concepts however, does not seem to be correlated to the maximum limit of blood alcohol concentration allowed for driving a vehicle. Countries such as Sweden, Holland and Great Britain present the same percentage of fatalities from drunk driving even though they have different maximum levels, 0.2, 0.5 and 0.8 g/l, respectively. Other factors, for example, laws that control driving and drinking, highway conditions, the use of intensive campaigns to control the consumption of other drugs, besides fervent patrolling, may explain this fact. 11 Most fatal car accidents occur on weekends and the vehicles operated by drivers who consumed alcohol is more prevalent between 9:00 p.m. and 3:00 a.m. 2 Drunk drivers tend to be repeat traffic offenders. Studies show that people who died in car accidents under the influence of alcohol had a higher probability of having committed at least one violation for driving under the influence of alcohol (DUI) in the previous 5 year period to the accident than sober drivers. 12 In Brazil studies show that after the implementation of the Brazilian Traffic Code in 1997, there has been little change in the behavior of drivers in regard to drinking and driving.22 Studies on fatal automobile accidents of which drunkenness was the cause, 50% of the victims presented the blood alcohol content four times higher than the maximum permitted by law. 13,14 It is important to emphasize that the use of alcohol should also be studied in emergency room attendance because it can be confused with symptoms of other diseases and exacerbate pre-existing problems. Medication, mainly anesthetics and analgesics, when mixed with alcohol, may interact in the organism and make patients more vulnerable to infections. Patients that involve themselves in situations where alcohol was an important factor tend to involve themselves again in similar problems in the future. 15 VERIFICATION AND TESTING METHODS OF ALCOHOL USE IN DRIVERS The two methods most used around the world to determine drunk driving are the breath analyzer (popularly known in Brazil as the bafômetro ), and blood tests. Urine and saliva can also be tested. 168

7 Specific problems: Alcohol and motor vehicles Breath analyzer evidence (evidence that would hold up in court) is based on infrared detecting systems, or combustible cells. There is a coefficient of 1:2000 between blood alcohol concentration and concentration in exhaled air: a measure of 0.2 g/l of blood corresponds to 0.1 mg/l of air exhaled by the lungs. Note in Table 2 that the United States and Great Britain adopted a limit of 0.8 g/l and countries in the European continent adopted limits of 0.5 g/l or less. However, there is not a clear correlation between blood alcohol concentration limits and fatalities. For this reason a law needs to be approved to establish one limit, and should be accompanied by public intervention and pressure to be effective. Table 2 Blood alcohol concentration limits permitted while driving a vehicle and death rates Country Limit (g/l) Fatal victims / 100,000 inhabitants Brazil 0.2* 14.0 Canada China France Germany India Italy Japan Mexico Panama Paraguay Russia South Africa South Korea Sweden United Kingdom ** USA Uruguay * Present limit as from June 2008 **mortality rate refers to Great-Britain only Source: Global Road Safety Partnership 2 e International Traffic Safety Data and Analysis Group

8 Alcohol and its consequences: dealing with multiple concepts PEDESTRIANS Pedestrians are very seldom included in studies on traffic accidents even though they are very vulnerable to this type of accident. In Brazil, 30% to 46% of the pedestrian deaths cause by a vehicle had a positive BAC, frequently over 1.0 g/l. Studies show that pedestrians proven to be under alcohols effects before the accident tend to stay in hospitals for longer periods, sustain more serious injuries, suffer more post trauma complications, and are more frequently traumatized in the thorax or spinal column than sober pedestrians involved in the same kind of accident. It is also important to stress that the predominant intoxication of pedestrians occurs during night time hours. 15,17,18 INTERVENTIONS From the public health point of view, control over driving under the influence of alcohol should be composed of many measures: economic sanctions: --prices and taxes; --public policy actions; --laws of driving under the influence of alcohol; --establishment and reduction of maximum limits of blood alcohol concentration allowed; --sobriety checkpoints; --higher fines for drunken drivers; --warnings on alcoholic beverage cans and labels; --minimum age laws for the selling and consumption of alcoholic beverages; organizational actions: --availability of alcohol; --enforcement of laws on driving under alcohols effect; --control of liquor stores on federal and state highways; --education and health: --school programs on the effects of alcohol and driving; 170

9 Specific problems: Alcohol and motor vehicles --radio and T.V. campaigns; --community programs. Laws have much more impact when they are accompanied by a series of steps: publicity, public education, awareness campaigns on the new laws and fines, and the participation of law enforcement, to increase the perception of the risks involved in case of non-compliance with the laws. However, before these laws can be implemented, it is necessary to analyze the dimensions and dynamics of the problem through epidemiological studies for the federal money not to be spent in vain and the strategies of control to become ineffective. This type of survey can be done by breath analyzer tests conducted both on the scene of accidents and at random, on federal highways and state roads. Conducting autopsies on victims of fatal car accidents to determine presence of toxic substances and/or studies in hospital emergency rooms where victims of automobile accidents receive first aid treatment. Economic sanctions Public policies that impose higher taxes on the distribution and commerce of alcoholic beverages have a positive effect on reducing the consumption. It is estimated that a 10% hike in prices will reduce the occurrence of drivers under alcohol influence by at least 7% to 8%. 19 Public political actions Specific traffic laws to control the driving of vehicles by drivers under the influence of alcohol should be restrictive, either establishing maximum blood alcohol concentration limit, or reducing a previously established one. The determination of different limits according to the drivers age was established in the United States, where limits for individuals under the age of 21 were effective in reducing fatalities. However, in countries such as Brazil in which the minimum age to drink and get the driver s license are the same (18 years of age), there is no reason to establish this type of law. 171

10 Alcohol and its consequences: dealing with multiple concepts Establishment and reduction of maximum limits of blood alcohol content Laws establishing the maximum level of BAC for drivers could involve two classifications per se, the first being in which the simple presence of alcohol in the blood is proof enough to establish that the motorist is unable to drive, and courtroom proof of the driver s altered physiological behavior are not demanded; and secondly laws in which it is necessary to prove the driver was unfit to drive. Since incapacity to drive is proven by alterations in behavior that are highly subjective, the possibility of evidence being contested in court is greater. 11 Norway is given credit for establishing the first per se limit in 1936 with a maximum limit of 0.5 g/l. The actual limits of BAC vary from 0.2 g/l (as the current limits in Norway and Sweeden) up to 1.5 g/l. There are countries such as Brazil, Germany, and Finland that have established more than one limit and varying restrictions. One of the first studies of the effectiveness of establishing a 0.8 g/l maximum limit was done in 1973 by Ross in Great Britain and it reported 23% and 11% reductions in the number of fatalities and in serious injuries after the law was sanctioned, respectively. One year after the law was put into action, the proportion of drunken drivers with BACs above 0.8 g/l fell from 32% to 20%; after 3 years in action and in another subsequent study, the indexes return to their pre-law levels, but a small enduring effect on accidents, deaths, and injuries was noted. A similar study, done in the United States evaluated the impact of a law establishing per se limits of 1 g/l. The results showed that the number of fatalities with levels between 0.1 g/l to 0.9 g/l fell 13.2%, and levels above 1 g/l decreased by 8.7%. 3,19,21 In Australia the maximum limit was reduced from 0.8 g/l to 0.5 g/l, and as a result there was an expressive reduction in drunken driving observed, especially in levels above 0.5 g/l (32.7%) and 0.8 g/l (38.2%). 19 In Norway a study on the impact of a law reducing the maximum limit from 0.5 g/l to 0.2 g/l, showed a 6% to 11% reduction in traffic accidents. The mean BAC found in fatally injured drivers fell from 1.68 g/l to 1.54 g/l. These numbers 172

11 Specific problems: Alcohol and motor vehicles corroborate the conclusion that the reduction was greater for drivers with BACs above 1.5 g/l than those with lower levels. 9 In the United States comparative studies show that the reduction of the maximum limit from 1 g/l to 0.8 g/l reduced fatal accidents by 16% in states where the reduced limits were adopted. 11 The reduction of the maximum limit in Brazil, from 0.8 g/l to 0.6 g/l, with the introduction of the Brazilian Traffic Code in 1997 was responsible for a 20% reduction of traumas suffered by passengers of motor vehicles and a 9% reduction in motorcyclist injuries. The reduction of drivers under the influence of alcohol was only observed in the last group; however, the measures of drunkenness were subjective and the data came from emergency ambulatory workers (who, when interviewed, said that they could detect alcohol on the breath of the victims), which does not allow a more objective analysis of the data. Recently, with the introduction of the law n , in June, 2008, the reduction of the maximum limit to 0.2 g/l, caused a decrease of 43.5% in emergency room attendance of car accident victims, and a 13.6% reduction in deaths from automobile accidents, even though there was a 4.3% increase in the number of automobile accidents, but with fewer mortalities. These numbers lack proper scientific analysis, but they do indicate tendency of fatal accident prevention during the period since the law was enacted. Capital cities where traffic control was more intensive showed more positive results. Sobriety checkpoints Checkpoints of sobriety are police patrol strategies for testing blood alcohol content in drivers. In European countries and in Australia, where legislation permits, motorists are stopped and asked to take breath analyzer tests in a systematic manner. In other countries such as the United States the patrolman has to suspect use of alcohol in order to ask the driver to take the test. Checkpoints were responsible for a reduction of 20% of alcohol related collisions, and a 30% decrease in the number of fatalities, according to studies done in North America and Australia. The success of checkpoints however, depends on the inspection of authorities and campaigns, so that the drivers may 173

12 Alcohol and its consequences: dealing with multiple concepts have a real perception of the possibility of being fined in case of infractions. The implementation of sobriety checkpoints provides to the government a profit of $6 for every dollar invested. 19 Higher fines for drunk driving Studies indicate that higher fines with the threat of prison sentences do not reduce the statistics of automobile accidents, however, steeper measures, such as license revocation or suspension have are more effevtive. 19 Even so, studies show that motorists who died in traffic collisions and were proven to have a blood alcohol content above 0.2 g/l were more likely to have been arrested for a DUI violation in the 5 years prior to the accident than motorists who died in automobile accidents where alcohol was not a contributing factor. 12 Warnings on beverage labels Warning labels alerting the motorist on the risks of operating heavy equipment after ingesting alcoholic beverages as well as suggestions on moderate drinking seem to have worked in making the population more aware of the. However, the long-term effectiveness of this method has not been proven; data related to the success of this action are rare and inconclusive. 19 Minimum age laws for the selling and consumption of alcoholic beverages The raising of the minimum age limit for the consumption of alcoholic beverages in the United States and Great Britain diminished the problems related to alcohol and teenagers, as well as reduced the number of fatal accidents involving this age group. 11,19 Organizational actions Restricting the availability of alcoholic beverages can be accomplished by reducing the hours, days of the week and places where beverages are sold. The 174

13 Specific problems: Alcohol and motor vehicles prohibition of sale in specific situations, for example, during sports events has shown a reduction in accidents related to alcohol consumption. Changes in commercial functioning hours and selling outlets show alterations in the incidence of traffic accidents and homicides. Server s training (mandatory in some states in the U.S.) reduced evening collisions by 23%. Training consists of educating the employees of bars and restaurants to restrain their clients from drinking excessively and/or involving themselves in situations of risk such as driving. Employees are also trained to not sell drinks to customers that clearly show signs of being drunk or are behaving in an altered state. 19 In a study that evaluated customers of a bar (Road Crew) where the drinkers were offered lifts home in luxury cars paid for by the establishment resulted in less accidents related to drunkenness and driving. 20 Education and health Educational programs in schools have limited effectiveness in the reduction of consumption of alcohol among teenagers in general. The most effective programs are promoted by students organizations, not by the principals and teachers. However, schools can be centers of group discussion on the harmful effects of abusive alcohol consumption. Other forms of approaching the public are in counter-advertising, or advertisement warning about the risks of abusive alcohol consumption. When it is done methodically, it can serve by increasing knowledge, changing norms and attitudes, and promoting healthy lifestyles. Counter-advertising is more effective when accompanied by public support and law enforcement. 19 Community action also can result in positive effects on legislation and enforcement. One example is Mothers Against Drunk Driving (MADD) that through community mobilization was able to change public opinion and got support for the modification of laws and more severe punishment for drunken drivers. 175

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