Ir Med J. 2006 Mar;99(3):80-3



Abstract
Although it is known that alcohol is associated with a high proportion of fatal accidents and suicides, little information is available in Ireland on blood alcohol concentrations (BACs) of those who died. This study was undertaken to identity the (BACs) in persons who died as a result of suicide or injury. The study was a retrospective review of coroners records to identify BACs in three counties in Ireland. All cases where the person died as a result of injury or suicide in 2001 and 2002 were included. There were 129 deaths eligible for inclusion. Of these, 98(76%) were male, 55(42.6%) were road traffic accidents (RTAs), 31 (24.0%) suicides, 12(9.3%) substance misuse, 11(8.5%) house fires and 20(15.5%) others. Of the 55 who died as a result of RTAs, 22 (40%) had positive BACs ranging from 16mg/100ml to 325 mg/100ml. Of the 31 who died as a result of suicide, 28(90.3%) were male. BACs were available for 29(93.5%). Of these, 16(55.5%) had alcohol detected. Persons aged less than 30 years were more likely to have alcohol in their blood (p<0.002). The mean BAC for persons aged less than 30 was 191.5 mg/100ml compared to 84.0 mg/100ml for those aged 30 and over. The mean BAC for adults who died in house fires was 225.2 mg/100ml. The high BACs in those who died as a result of suicide or injury reflect the high level of alcohol consumption and binge drinking in Ireland.



Introduction
Alcohol is a major risk factor in the lives of young people and is implicated in a quarter of all deaths of young men in Europe aged between 15 and 29 years. The majority of these deaths result from injuries (intentional and unintentional).¹ Alcohol is estimated to be associated with at least 40% of all fatal road traffic accidents (RTAs)² and with a significant proportion of suicides amongst young men.³

Ireland has one of the highest alcohol consumption rates in Europe. This is compounded by a culture of binge drinking.⁴ Binge drinking, apart from any long term effects, can have immediate harmful effects resulting from impulsive behaviour and may lead to accidents or suicide. An increase in the number of emergency admissions of intoxicated patients to acute hospitals has been shown to mirror the increase in alcohol consumption in Ireland.⁵ This study was undertaken to identify the blood alcohol concentrations in persons who died as a result of accidental death (including accidents on the roads, at home and at work) or suicide.

Methods
The role of the coroner is to enquire into the circumstances of sudden, unexplained, violent and unnatural deaths. The coroners records in respect of all such deaths that occurred in the counties of Cavan, Monaghan and Louth in 2001 and 2002 were examined by the first author in the offices of the coroners. Any deaths that were the result of an accident, suicide or injury were reviewed in detail for inclusion in the study. Data on age, gender, marital status, occupation, blood alcohol concentrations and date and time of death were collected. All blood samples were taken at the post-mortem examination. The details of how the blood samples were taken were not available in the coroners records and the time intervals between the time of death and the taking of the samples were not recorded. The definition of suicide used in this study was that death was self-inflicted and intended. This was based on the judgement of the authors, incorporating such criteria as mode of death and whether or not the deceased expressed intent of suicide. Not all coroners or juries at inquests use the term suicide in their verdicts.

Deaths which were not considered to be accidental, suicide or injury in nature were not included in the study. Deaths considered to be unlawful killings or murder (based on the coroners records) were also excluded. The data was collated and analysed using JMP and STATA, two statistical software packages. Percentages, medians and means were calculated. Statistical significance was assessed by using Chi-square test or the Fishers exact test. Where appropriate, multivariate analysis was also carried out to calculate odds ratios. It was not possible to calculate population rates for the counties involved as some of the deaths were in respect of persons who resided outside of the counties and similarly other persons from the three counties may have died in other counties not included in this study.

Results
There were a total of 129 deaths. The majority 98 (75.9%) were male and 113 (87.5%) were adults aged 18 years and over. Blood alcohol levels (BAC) were tested for the majority 105 (81.3%) of the study population, of whom 58(55.2%) tested positive for alcohol. The females were as equally likely as the males to have their BACs tested (74.1% vs. 83.6%, p>0.05). The females were also as equally likely as the males to have a positive BAC (60.8% vs. 53.6%, p=0.63). Table 1 outlines the category of event that caused death.

Road Traffic Accidents (RTAs)
Of the 55 who died as a result of RTAs, 40(72.7%) were male. The mean age was 33.7, standard deviation (SD) 20.4 (range 2-84 years) and the median age 27 years. Just over half, 28 (50.9%) occurred during the night-time.

Twenty-five (45.5%) of those killed were drivers (23 cars and 2 other vehicles), 20 (36.4%) were passengers and 10 (18.2%) were pedestrians. Twenty-two (55.0%) of the males were drivers, 11 (27.5%) were passengers and 7 (17.5%) were pedestrians, while 3 (20.0%) of the females were drivers, 9 (60.0%) were passengers and 3 (20.0%) were pedestrians. Males were 4.9 times more likely than females to be the driver of a vehicle involved in an accident causing a fatality (Odds Ratio 4.9; CI: 1.04-26.3, p<0.03).

BACs done as part of the post mortem examinations were available in respect of 42 (76.4%) of those killed. Overall, 22 (40.0%) had alcohol detected in their blood samples. The BACs ranged from 16mg/100ml to 325 mg/100ml.

The following provides more detailed profiles of alcohol levels for drivers, passengers and pedestrians.

Drivers and alcohol
Of the 25 drivers killed, 21 had BACs recorded of which 7(33.3%) had alcohol detected in their blood, all of whom were male. The BACs ranged from 26 to 257 mg/100ml. The mean concentration was 148.4 mg/100ml (SD: 87.1) and the median 165 mg/100ml. Of the 5 drivers with BACs greater than the legal limit of 80mg/100ml, 4(80%) were aged in their twenties. Male drivers in their twenties were more likely to have a BAC higher than the legal limit than drivers of any other age (p<0.03). Drivers who were killed during night-time accidents were 8 times more likely to have a positive BAC compared to those drivers killed during the daytime, (OR 8.0, 95% CI 0.7 to 85.1, p<0.08). The BACs for adults are summarised in Table 2.

Passengers and alcohol
Twenty passengers were killed of whom 11(55.0%) were male. Six (30.0%) were children (i.e. aged less than 18 years), one of whom had a BAC recorded at 136mg/100ml. Of the remaining 14 passengers, all 18 years and over, 13(92.9%) had BACs recorded. Of these, 10 (76.9%) had alcohol detected in their blood. The BACs ranged from 16 to 286 mg/100ml. The mean blood level was 151.9 mg/100ml (SD: 92.0) and the median 175 mg/100ml. The BACs for adults are summarised in Table 2.

Pedestrians and alcohol
Ten pedestrians were killed of whom 7(70.0%) were male. Their ages ranged from 3 to 84 years with a mean of 40.9 (SD: 30.7) and a median of 34. Three were children (i.e. those aged less than 18 years). Six of the 7 adults had BACs recorded. Of these, 4 (66.7%) had alcohol detected in their blood. The BACs ranged from 72 to 325 mg/100ml. The mean concentration was 175.3 mg/100ml (SD: 107.1). The two who had the highest blood alcohol concentrations were both aged in their twenties. The BACs for adults are summarised in Table 2.

Suicide
Of the 31 who were considered to have died as a result of suicide, 28(90.3%) were male.

Twelve (38.7%) were aged less than 30 years, 13(41.9%) were aged 30-64, 5(16.1%) aged 65 and over and for 1(3.2%) age was not stated. Twenty (64.5%) were single, 9 (29.0%) were married and 2 (6.4%) were separated/divorced. Sixteen (51.6%) died by hanging, 9 (29.0%) by drowning, 3 (9.7%) by gunshot and 3 (9.7%) by other means.

BACs were recorded for 29 (93.5%). Of these, 16 (55.5%) had alcohol detected in their blood. The BACs ranged from 13 mg/100ml to 317 mg/100ml. The mean was 157.9 mg/100ml (SD: 91.7) and the median was 134 mg/100ml. Persons aged less than 30 years of age were significantly more likely to have any alcohol in their blood (p<0.002) and to have BACS above 80 mg/100ml (p<0.001) than those aged 30 years and over as seen in Table 3. Over half of those aged less than 30 years had BACs in excess of 160 mg/100ml. None of those over 30 years had such high levels. The mean BAC for persons aged less than 30 was 191.5 mg/100ml compared to 84.0 mg/100ml for those aged 30 and over.

Other Accidental Deaths
As seen in Table 1 there were 43 deaths that were neither RTAs nor suicides, 30(69.8%) of which were in respect of males. Seven (16.3%) were children (i.e. aged less than 18 years of age). Only 2 children had BACs done and both were negative. Of the 36 adults, 31(86.1%) had BACs recorded at post-mortem, of whom 18(58.1%) had alcohol detected in their blood. The BACs ranged from 26 to 589 mg/100ml, with a mean of 260.1 mg/100ml (SD: 149.9) and a median of 254.5 mg/100ml. Table 4 outlines the BACs by incident type in respect of the 36 adult deaths.

As seen in Table 4, all adults killed in house fires who had BACs recorded had BACs greater than 80mg/100ml and half had BACs greater than 240 mg/100ml. The mean BAC for those adults who died in house fires was 225.2 mg/100ml. None of those who died as a result of an industrial or farming accident had alcohol detected in their blood.

Discussion
This study highlights the high level of alcohol consumption in those who have died from accidents or suicide. It is reasonable to expect a similar profile to occur nationally as national studies have shown these counties to have similar levels of alcohol consumption to the national average4 and given that BAC levels were carried out in the majority (over 80%) of the study population (and equally likely in males and females).

Alcohol related RTAs are preventable. In this study a fifth of the drivers killed had alcohol concentrations above the legal limit, a significant reduction on the 46% in a study thirty years ago.⁶ Of those drivers who died and had alcohol detected in their blood 80% were aged in their twenties and all male. This is in keeping with the evidence which shows that at all BACs, young drivers are at greatest risk of a fatal crash with the risk five times greater for teenagers and three times higher for those in their twenties.⁷ There are still large numbers of drivers who drink alcohol and drive. Over a quarter of males in Ireland admit to driving soon after consuming two or more drinks.⁴ Successive national safety campaigns and limited enforcement of the legislation have failed to reduce the prevalence of drinking and driving (28% in 1998, 27% in 2002).⁴ Ireland has a low level of enforcement of drink driving legislation compared to best practice countries⁸ with less than one person per licensed premises in Ireland arrested for drink driving per year. This low level of intervention is reflected in the high rate of alcohol related road fatalities in Ireland compared to those countries where high rates of intervention and enforcement result in much lower rates of alcohol related road fatalities; as low as 18% in Australia and 25% in Finland.⁸ Higher visibility of enforcement is required particularly for men, as the risk of being breathalsysed is the main reason why they may consider not drinking before driving, not safety issues.⁹ The legal limit for driving in Ireland is 80 mg/100ml. Lowering this limit by itself is unlikely to be a greater deterrent to drivers as in 2002 in Ireland the mean BAC in those arrested for drinking and driving was 174 mg/100ml, over double the legal limit.¹⁰ Random breath testing can significantly reduce RTAs and can reduce alcohol related fatalities ¹¹ and needs to be introduced as a matter of public policy here in Ireland.

Almost half of all the adult passengers killed had BACs greater than 160 mg/100ml (double the legal limit for driving) and reflect a high level of binge drinking. The proportion of passengers with such high alcohol levels is higher than other reported rates¹² and perhaps alcohol intoxication of passengers may be having some effect on drivers and their ability to drive safely.

There has been a major rise in suicides in young people in Ireland over the last ten years, in particular amongst young men. The impulsive nature of many of these has been highlighted.¹³ This increase in young suicides has occurred at a time of major changes in Ireland, one of which has been the large increase in alcohol consumption, a 41% increase in the 1990s. The role alcohol plays in suicide is well known.^13,14 Alcohol increases the risk of impulsive actions and it has also been suggested that the consumption of large amounts of alcohol increases the risk of a fatal outcome in suicide attempts.¹⁴ The BAC findings in this study, particularly amongst those under 30, are amongst the highest reported in the international literature.¹⁵ With over 90% of those aged less than 30 years having alcohol in their blood, 83% with BACs greater than 80 mg/100ml, over half with concentrations greater than 160 mg/100ml and a quarter with BACs over 240 mg/100ml, the data suggest that alcohol plays a far bigger role in suicide amongst young persons in Ireland than was previously thought. Many factors contribute to suicide. However, alcohol is clearly playing a major role, particularly amongst the young.

Fifty one persons died nationwide as a result of fires in 20028, the majority of which were house fires. Alcohol has been considered a contributory factor in 51% of fires¹⁶ involving deaths of persons aged 20 years and older in Ireland. This study suggests that alcohol may have a bigger impact with 100% of adults who died and who had BACs recorded, having BACs greater than 80 mg/100ml and 50% having BACs greater than 240 mg/100ml. However, the numbers in this study are small and further research such as a national study is required.

Conclusion
This study has highlighted the huge contribution alcohol makes to accidental deaths and to suicides. Given that the overall level of drinking in a population is significantly related to the alcohol related problems that population will have¹, it is vital that the level of consumption in Ireland is reduced as recommended by the recently published Strategic Task Force on Alcohol and its evidence based strategies implemented.¹⁷ Many of these recommendations will be unpopular in certain sections of our community and with vested interests. Without political leadership at the highest level, similar to that shown in the fight against tobacco related illness, alcohol will continue to be responsible for the unnecessary deaths of many more people in Ireland in years to come.

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