Alcohol contributes to violence, suicide, injuries, approximately 60 medical conditions,2 and is responsible for over 1000 deaths and 12,000 years of life lost each year in New Zealand.3 Consequently, alcohol is thought to have a significant impact on New Zealand health systems, specifically on emergency departments (EDs).
Between 2006 and 2011, alcohol-related admissions to New Zealand hospitals increased by 18.4% with Canterbury District Health Board hospital alcohol-related admissions rising from 16,220 patients per year to 19,180. The cost of approximately 6000 patients was estimated at NZ$27.4 million,3 meaning around 20,000 patients would cost ~$80 million.
The Sale and Supply of Alcohol Act 2012 was passed partly to reduce the harm caused by alcohol.4 Among other measures, it gave territorial authorities the power to develop local alcohol policies (LAPs) to control licensing and restrict access to, and availability of alcohol.
The Christchurch City Council’s proposed LAP includes restrictions on trading hours, and is due to be implemented in 2014. To assess the impact of the LAP on drinking behaviours, it was considered necessary to characterise drinking behaviour before, and after, its introduction. This study is part of the ‘before’ component of such an assessment.
Christchurch Public Hospital is the largest tertiary, teaching and research hospital in the South Island. It has one of the busiest emergency departments (EDs) in Australasia, treating more than 83,000 patients a year. The purpose of this study was to determine the impact of alcohol-related presentations on the ED before the Christchurch City Council LAP implementation.
Patient enrolment—Over 42 8-hour shifts between 15 November 2013 and 9 December 2013, patients were enrolled who presented to the ED with recent alcohol consumption or alcohol-related medical conditions. Data collection was not consecutive, but totalled 2 full weeks of time with all three shifts covered per day. The shifts were defined as ‘day’ (8:00 to 16:00), ‘evening’ (16:00 to 23:00), and ‘night’ (23:00 to 8:00 the following day).
All patients were asked if they had consumed alcohol in the 4 hours prior to their time of triage, and if they thought their ED attendance was related to alcohol consumption. Clinician judgement contributed to answering the latter question. Patients were eligible for the study if they answered yes to one or both questions (defined as ‘screen-positive’). Of the screened-positive patients, if alcohol contributed to a patient’s reason for attending the ED, s/he was classified as ‘impact-positive’. Patients under the age of 16 were included only if both patient and parental consent were obtained.
Patients who could not be interviewed and had no family or friends available to assist with the interview were tracked retrospectively to determine their eligibility, using notes and staff consultation. If there was a strong suspicion of alcohol contributing to the presentation these patients were listed as ‘unknown.’ Similarly, any sober patients who had been drinking, but for whom it was unclear if their presentation was alcohol-related, were also classified as ‘unknown’. By recording these patients as ‘unknown’, the number of patients recorded as ‘alcohol impacted’ would be underestimated, but the possible extent of the underestimation would be defined.
The following information was recorded for all the patients enrolled in the study: admission date and time, National Health Index number, date of birth, age, gender, ethnicity, current residential address, reason for attendance, length of stay in the ED, and any disruptive behaviour. Disruptive behaviour was defined as physical or verbal abuse that intimidated ED medical and nursing staff, or a physical or verbal action that impeded the process of care (as reported by ED staff).
The study also aimed to determine the completeness of data routinely entered into the ED computers. Records were checked on alcohol consumption in the four hours before patients were triaged and the number of presentations where alcohol consumption contributed to the problem.
The ED computer system has fields for recording answers to these questions, which are filled when patients are discharged. Datasets were extracted from the computer system for both the study period and comparable time intervals outside the study period (Box 1), to determine if the presence of the researchers in the ED influenced record keeping.
Box 1. Time periods of clinical record analysis
15 November 2013 to 9 December 2013
26 November 2012 to 9 December 2012
Two weeks beforehand
28 October 2013 to 10 November 2013
29 October 2012 to 11 November 2012
Two months beforehand
10 September 2013 to 23 September 2013
9 September 2012 to 22 September 2012
The contexts or types of illnesses and injuries that patients presented to the ED with were recorded and grouped into six general categories: non-interpersonal trauma, interpersonal trauma caused by violence, deliberate self-harm (including patients suffering from psychological effects of withdrawal symptoms), alcohol excess, motor vehicle accident trauma, and other.
Data were summarised descriptively using Microsoft Excel software, version 2010 (Microsoft, Redmond, WA).
Ethical approval was granted by the local Health Research Council Regional Ethics Committee.
Patent recruitment—A total of 3,619 patients were screened during the 42 shifts of the study (Figure 1). Of these patients, 297 were eligible for the study. Twenty-nine of the eligible patients were recorded as ‘unknown’, either because their clinical conditions prevented an interview, or because they left the department before enrolment.
Of the 268 screen-positive patients, 182 were impact-positive (i.e. alcohol consumption clearly contributed to the reason for their presentation). The remaining 86/268 screen-positive patients answered yes to having consumed alcohol in the 4 hours prior to their arrival, but alcohol did not contribute to their attendance. The latter generally included patients who had a glass of wine or a beer with dinner, but attended the ED for unrelated reasons. Fourteen of the 268 (5%) screen-positive patients were repeat presentations.
Numbers of patients per shift and day—Table 1 and Table 2 present numbers of screen-positive and impact-positive ED attendances per shift and day of the week. Most impact-positive patients (57%; 103/182) presented to the ED during the weekend from Friday evening through to Sunday evening (Table 2). Most of these patients (54%; 56/103) attended on Saturday.
In total, impact-positive patients accounted for approximately 10% (56/583) of all patients that attended the ED on Saturdays. The most impacted shift was Saturday night, when 25% (30/122) of all patients who attended the ED were impact positive. This was followed by 14% on Friday night (14/100), 8% on Sunday day (18/226), 6% on Saturday day (16/260), and 5% on Saturday evening (10/201). On the two Sunday nights, the number of impact–positive attendances had dropped to two patients.
During the week (Monday to Friday) day shifts, <5% of all patients attending the ED screened positive (Table 1), but alcohol consumption contributed to most of these presentations (83%; 15/18). On most week days, the percentage of impact-positive attendances increased between day and evening shifts.
Between Monday and Thursday, fewer impact-positive patients attended the ED at night compared with the evening. Many impact-positive patients attended the ED on Tuesday night.
Gender distributions—Figure 2 and Table 3 present the gender distributions per shift for each repeat day. Approximately two-thirds (65%) of impact-positive patients (118/182) were males. Of these, 68% (80/118) attended the ED between Friday and Sunday and 29% (23/80) attended on Saturday nights.
The numbers of impact-positive males who attended the ED increased throughout the day on Friday to level off on Saturday and peak on Saturday night (Figure 2). During Sunday, numbers dropped to parallel Friday day and evening shifts. The two Sunday night shifts received one male in total.
Slightly more than half (56%) of the impact-positive female patients (36/64) attended the ED between Friday and Sunday. Twice as many impact-positive males (n=62) than females (n=29) presented to the ED during the weekend. On Saturday night, the ratio of males to females was 3:1. Females attended the ED in even numbers across the weekend shifts, except Saturday evening when no impact-positive females attended (Table 3). The gender difference was less significant on Thursdays.
During the week (Monday to Thursday), impact-positive attendances were low for both genders. No females attended the ED during the day shifts of Wednesday and Thursday (Figure 2). Male impact-positive attendances were slightly higher on Tuesday and Wednesday evenings.
Age distributions—More males than females of all ages were impact-positive (Table 4; Figure 3).
The most significant age group was 16–25 years for both genders (males 37% (44/118); females 41% (26/64)). More than half of the <25 year old impact-positive patients (males 61% (28/46); females 52% (14/27)) attended the ED during the nights shifts. Most young males (n=17) attended during the Saturday night shifts.
The second most significant age group was 41–60 years where 32% of males (38/118) and 33% of females (21/64) were impact-positive (Figure 3a and 3b). In contrast to 16-25 year old impact-positive males, 58% of middle-aged males (22/38) attended the ED during the evening shifts (Table 4).
During the week days (Monday to Thursday), impact-positive females aged 16-20 years more frequently attended the ED than males of the same age (Figure 3b). Males aged 41-55 years and 46-50 years also peaked between Monday and Thursday.
Disruptive behaviour—Among the screen-positive patients, 16 displayed disruptive behaviour and 13 of these were impact-positive. Except for Saturday, generally one disruptive patient was observed on either of the two evening or night shifts (Table 5). On Saturday, a total of seven disruptive patients attended during the two evening and night shifts—six of these patients were impact-positive.
Context of medical conditions—Of the impact-positive males, 38% (45/118) attended the ED for non-interpersonal trauma (Table 6; Figure 4a). Non-interpersonal trauma accounted for 39% (17/44), 50% (13/26), and 29% (11/38) of 16–25, 26–40, and 41–60 year-old male presentations, respectively. Interpersonal trauma due to violence was also a common reason why 16-25 year old males (32%; 14/44) attended the ED on Saturday nights (Figure 4b).
Alcohol excess was the third most common reason males attended the ED (Figure 4c). In contrast to males, impact-positive females more frequently attended the ED for deliberate self-harm (36%; 23/64) on the weekends and on Mondays and Tuesdays (Figure 4d).
Almost half of the impact-positive female patients treated for deliberate self-harm were under the age of 25. Non-interpersonal trauma was the second most common reason females attended the ED and most presentations were during the weekend.
Accuracy of routinely recorded ED data—Patient data captured in the ED computer system accurately identified 86% (156/182) of the impact-positive patients.
Table 7 compares ED records for impact-positive patients between three two-week intervals in 2012 and 2013 (See Box 1 for full dates). For October/November, the number of alcohol related patients recorded is similar for both years.
The difference between years for September and November/December is more significant. The percentage of patients attending the ED increased between September 2012 and December 2012 and the respective interval in 2013.
A notable increase in patient attendances was recorded between September and October/November (20 in 2012; 23 in 2013) and between October/November and November/December (22 in 2012; 33 in 2013).
This study found that patients with alcohol-related injuries or illnesses had a significant impact on the ED. The percentage of screen-positive attendances (7.4%) is similar to that reported by McDonald et al5 (7.9%) for EDs throughout the United States of America.
In comparison, Slack and Nana’s1 estimated 6,211 patients attended hospitals (not just the Christchurch Hospital ED) for all alcohol-related causes throughout Canterbury in 2011 at a cost to the hospital system of $27.4 million. Our figure suggests that this total number of cases of alcohol-related hospital attendances, and therefore the cost, may in fact be an underestimate.
The high prevalence of Friday and Saturday night impact-positive attendances is consistent with international reports. For example, a review of 28 EDs from six countries (US, Mexico, Spain, Italy, Canada and Australia), noted that alcohol-related presentations most often occurred between midnight and 4:59am on Fridays, Saturdays, and Sundays.6 Similarly, in Ireland, Hope et al7 found that most alcohol-related ED presentations were between midnight and 6am.
The 16–25 year age group was over-represented in both genders. Binge drinking amongst teenagers, especially males, is an international problem. Data from surveys in nine European countries and the US report that adolescent drinkers became intoxicated during 25% of their drinking sessions, compared with 17.5% of other adult drinkers.8 Binge drinking by young people in New Zealand has increased since the purchase age was lowered from 20 to 18 years in 1999.2
The high proportion of young males relative to females who attended the ED for alcohol-related reasons is consistent with the findings of Rehm and Room,9 who noted that, worldwide, 21.6% of injuries to males were alcohol-related, compared with 7.7% to females. However, in New Zealand, Kypri et al10 found that after the minimum alcohol purchase age was lowered, 51% more females aged 18 and 19 years were involved in alcohol-related vehicle crashes and hospitalised injuries. We found that young females who drink were more likely to present during the weekend.
The high percentage of impact-positive middle-aged males compared with females is consistent with the results of some overseas studies. For example, Lowenstein et al,11 found that the mean age of severely-intoxicated patients presenting to a US ED was 34 years and 70% were male.
Similarly, McDonald et al5 reported that patients between the ages of 30 to 49 years had the highest rate of alcohol-related presentations to EDs across the US, and the group was dominated by males. Furthermore, a review of 28 EDs from six countries reported that alcohol-affected males aged between 18 and 45 years presented most often.6
In New Zealand, the Ministry of Social Development12 reported that from 1996/97 to 2006/07, the percentage of ‘potentially hazardous drinking’ by males aged between 35 and 44 years had increased from 25.5% to 29%.
Alcohol-related disruptive behaviour is more likely to occur during evening and night shifts, especially on Saturday. The impact of the disruptive behaviour of even one patient can affect many staff, patients, and supporting friends and family members.
Physical or verbal abuse is intimidating and impedes the process of care. The Law Commission2 noted that alcohol abuse has led to a ‘…disturbing level of anti-social behaviours; from abusive and offensive language, intimidation, sexual harassment, graffiti and vandalism; to urinating, excreting and vomiting in public places.’
The high proportion of alcohol-related medical problems on weekend night shifts is consistent with international reports. However, studies classifying medical conditions associated with alcohol-related ED presentations are rare. Most studies evaluate a single context, such as motor vehicle accidents and compare it with blood alcohol concentration, or compare the rate of alcohol-related presentations with the rate of unrelated presentations (e.g. Cherpitel, 2007).13
We found that the genders differed in their types of alcohol-related medical problems. Non-interpersonal trauma (other than motor vehicle accidents) was the most common injury suffered by impact-positive males of all ages, but only the second most common for females.
In the 16-25 year age group, interpersonal trauma caused by violence was also common. In a review of studies from eight countries, Cherpitel13 reported that alcohol consumption was implicated in between 22% and 84% of violent inter-personal injuries. Similarly, Lowenstein et al11 found that 23% of intoxicated patients presenting to a US ED were the victims of violent assault, and a review of six EDs in Ireland found that it ranged from 32 to 42%.7
The relationship between alcohol consumption and self-harm in young females is alarming and raises the need for further research in this area. Excessive alcohol intake was the third most common reason for male attendance. These findings reflect the results of the NZ Mental Health Survey,14 which found that 12.3 % of the population had abused alcohol or drugs at some time in their life, and that abuse was most prevalent in the 15–24 year age group.
Males are more than twice as likely to be represented in substance abuse statistics as females, but more females (56.6%) than males (36%) experience anxiety, a mood disorder or an eating disorder at some time in their life.
There was a low percentage of alcohol-related motor vehicle accident trauma in Christchurch, which might relate to stricter enforcement of drink driving laws over recent years. The incidence of vehicle crashes in New Zealand that involved alcohol causing death fell from 38% in 1993 to 33% in 2012, while those which resulted in injury fell from 20% to 15%.15 In some less-developed countries, motor vehicle accident-related trauma of alcohol-affected patients has been reported to be considerably higher than in this study (e.g. 8.3 to 16.8% in Mexico).16
The increase in the number of impact-positive patients recorded by clinical staff between 2012 and 2013 may relate to the influence of the researchers. Our findings suggest that at least 14% of impact-positive attendances are not recorded.
Under-reporting of alcohol-related presentations is a general concern. US studies that reported 2.7% and 3.1% of all presentations to EDs as alcohol-related17,18 were thought to have underestimated the true figure by half.5 McDonald et al5concluded that patient disclosure and/or physician documentation of alcohol-related presentations are unreliable. In the UK, Alcohol Concern19 reported that surveys of alcohol consumption in the UK under-estimate the volume of alcohol consumed by 40%.
The increase in numbers of impact-positive presentations in late November/early December may in part relate to greater alcohol consumption associated with festivities in the build-up to Christmas, because numbers had been increasing since September. The same pattern was also evident in 2012.
However, the significant increase in the months of November and December between 2012 and 2013 warrants more research, because it might reflect an important on-going trend. For example, Slack and Nana1 reported that alcohol-related ED presentations in Canterbury increased by 8.4% between 2006 and 2011.
Similarly, Rehm and Room9 noted that throughout the world, years of life lost from injuries attributable to alcohol increased by 6.3% from 2000 to 2005: the increase was twice as great for females (8.8%), as for males (4.1%).
Limitations—This study had a number of limitations. Firstly, the timing of the study might not be representative of drinking behaviours throughout the year. Alcohol consumption would be expected to rise during the lead-up to the Christmas/New Year period. A number of events traditionally involving heavy alcohol consumption (such as the New Zealand Trotting Cup, Christchurch Show Day and the Christchurch Wine and Food Festival) fell within the study period.
The time between arrival and observation at the ED could have affected a patient’s level of intoxication. ED waiting times can be long for non-urgent presentations, so some patients might have sobered while waiting for care, and subsequently been classified inappropriately. Finally, 29 patients (about 15%) who were missed and retrospectively tracked through notes might or might not have been eligible to consent – there was reasonable, but unconfirmed suspicion of alcohol involvement or intoxication in their presentation. It is possible that more were missed during the busy weekend periods. If these patients were included in the study, there could have been a higher number of impact-positive patients.
Conclusion—This study demonstrated that alcohol has a significant impact on the ED, particularly during the weekends. Male patients aged 16-25 years and 41-60 years presenting on Saturday evenings and nights had the biggest impact. The present system where busy ED staff routinely record the impact of alcohol appears to underestimate the true impact of alcohol consumption on the ED and therefore on the wider community at the time of this study. Future studies could help determine if the increase in alcohol-related presentations between 2012 and 2013 are part of an on-going trend.