Alcohol and injury. A case-crossover study

Sober up: Time from last drink to a road traffic injury

PURPOSE

There is no intervention that quickly reduces a person's blood alcohol content (BAC). "Sober up before you drive" may prevent road traffic injury (RTI) caused by alcohol consumption. The aim of this study was to analyze the risk of RTI on an hourly basis (1-6 h) after the last drink and the determinants of this risk.

METHODS

This was a case-crossover study of alcohol consumption among 430 patients who suffered an RTI and arrived at an emergency department in a large hospital in Mexico City from January to April 2022.

RESULTS

Of the 430 patients studied, 46 reported drinking within 1 h before the RTI, for a risk ratio (RR) of 7.7 (95% CI [5.6, 10.4]). This RR decreased to 2.2 (95% CI [1.3, 3.7]) for the 12 patients drinking in the second hour before the RTI and was null for those drinking earlier (p ≤ 0.001 for the trend). The induction time was 3 h among those with higher BAC and intoxication levels. The RR for an RTI decreases 71% from the first to second hour from the last drink and 32% from the second to third hour. This decrease was similar among those intoxicated and those with increased BACs. In multiple regression models, higher levels of intoxication and higher BACs remained associated with higher RRs.

DISCUSSION

People should avoid driving after drinking. Waiting to drive, walking, or riding after drinking reduces the risk of an RTI, especially for people with higher BAC and intoxication levels.

Effects of Acute Alcohol Intake on Nasal Patency

BACKGROUND

Acute alcohol intake may influence nasal patency; however, there is lack of objective evidence.

OBJECTIVE

The aim of this study was to evaluate the effects of acute alcohol intake on nasal patency employing both subjective and objective measures.

METHODS

A total of 31 participants were classified into 2 groups of non-heavy drinkers (n = 17) and heavy drinkers (n = 14). Both groups consumed wine in 1 h and were assessed for subjective nasal symptoms and objective nasal patency, using rhinomanometry and acoustic rhinometry, at baseline and at 0.5, 2, and 6 h post-alcohol consumption.

RESULTS

Alcohol consumption significantly increased nasal obstruction from baseline values in both heavy and non-heavy drinking groups. Total nasal volume (TNV) and the minimal cross-sectional area (MCA) were significantly decreased and nasal airway resistance (NAR) significantly increased from baseline values by 2 h post-alcohol consumption for both heavy and non-heavy drinking groups (P < .05). Significant differences were found in TNV, MCA, and NAR between baseline and post-drinking in allergic rhinitis subjects; with no significant differences in MCA and NAR in subjects without allergic rhinitis. Pulse rate (PR) and temperature (T) were elevated, and blood pressure (BP) was decreased after alcohol consumption (P < .05). Blood alcohol concentration (BAC) was not significantly correlated with nasal patency with regard to any subjective or objective measurement.

CONCLUSION

Acute alcohol consumption may impair nasal patency, independent of the amount consumed. Individuals with allergic rhinitis may be more prone to nasal obstruction after alcohol consumption than those without allergic rhinitis.

Alcohol and tobacco consumption: What is the role of economic security?

AIMS

To better understand the longstanding inequalities concerning alcohol and tobacco use, we aimed to quantify the effect of household economic security on alcohol and tobacco consumption and expenditure.

DESIGN

Longitudinal analysis using data from the Household, Income and Labour Dynamics in Australia survey (2001-2018).

SETTING

Australia PARTICIPANTS: A nationally representative cohort of 24 134 adults aged 25-64 years (187 378 observations).

MEASUREMENTS

Tobacco and alcohol use (Yes/No), frequency of use of each per week, household expenditure on each per week, household weekly income (Consumer Price Index [CPI]-adjusted), employment security (based on conditions of employment) and housing affordability (housing costs relative to household income).

FINDINGS

At baseline, one-quarter of the sample used tobacco and 87% used alcohol. Annual increases in household income were associated with the increased use of both tobacco and alcohol for people in households in the lowest 40% of the national income distribution (OR = 1.13, 95% CI = 1.03-1.23 and OR = 1.12, 95% CI = 1.04-1.20, respectively) with no similar income effect observed for higher-income households. In relation to smoking, the odds of a resident's tobacco use increased when their household was unemployed (OR = 1.32, 95% CI = 1.07-1.62). In relation to alcohol, the odds of use decreased when households were insecurely employed or unemployed, or housing costs were unaffordable (OR = 0.87, 95% CI = 0.77-0.98, OR = 0.66, 95% CI = 0.55-0.80 and OR = 0.84, 95% CI = 0.75-0.93, respectively). This was also reflected in the reduced odds of risky drinking (defined in accordance with Australian guidelines) when housing became unaffordable or households became unemployed (OR = 0.90, 95% CI = 0.81-0.99; OR = 0.82, 95% CI = 0.69-0.98, respectively).

CONCLUSIONS

In Australia, smoking and drinking appear to exhibit different socio-behavioural characteristics and household unemployment appears to be a strong determinant of smoking.

Use of social media while driving from an orthopedic resident's perspective

PURPOSE

To investigate the orthopedic injuries sustained while driving and using social media on cellular phones from an orthopedic resident's perspective.

METHODS

A total of 118 patients who presented with a history of road traffic accident secondary to social media usage and suffered from fractures were included in this cross-sectional study. These patients were reported from October 2018 to April 2019. We collected the data including the type of collision, type of social media usage during driving, location of injury, wearing of safety equipment's such as helmet and seat belt during driving.

RESULTS

The mean age of patients was (34.86 ± 12.73) (range 15-71) years. The common types of accident on the basis of collision of vehicles were: car versus motorbike 45 (38.1%), motorbike versus motorbike 28 (23.7%), and motorbike versus pedestrian 22 (18.6%). Most of the accidents (61, 51.7%) occurred due to mistake of motor-bikers. Out of them, 44 (37.3%) occurred on traffic signals, followed by 29 (24.6%) while driving on main roads. The common timing of accident was normal hours with frequency of 44 (37.3%), followed by 39 (33.1%) at late night. According to fracture type, closed injuries were 98 (83.1%) and open fractures were 20 (16.9%). The most common fracture was clavicular fracture (21, 22.5%) followed by soft tissue injury in 19 (16.1%) patients. The most common social media application usage during driving was Facebook 43 (36.4%), followed by Whatsapp 24 (20.3%), Google 19 (16.1%), and Instagram 15 (12.7%).

CONCLUSION

This study provides evidence that social media usage while driving put the drivers and other road users' lives at high risk. The most common social media addiction while driving is Facebook and Whatsapp. So there is a need to make strict rules and penalties for using cell phone during driving so as to save the lives of drivers and other people using road.

Acute Alcohol Exposure and Risk of Mortality of Patients with Traumatic Brain Injury: A Systematic Review and Meta-Analysis

After traumatic brain injury (TBI), patients usually live with significant disability and socioeconomic burdens. Acute exposure to alcohol is considered a major risk factor for TBI. Numerous studies have examined whether alcohol exposure is related to the risk of mortality in patients with TBI, yet the results remain inconsistent. We performed a meta-analysis to assess whether acute alcohol exposure affects the mortality rate of TBI patients. We searched PubMed, EMBASE, and the Cochrane Library up to November 2015 for relevant studies. We screened studies based on their inclusion criteria and selected the studies that reported mortality rate, which included 18 observational studies. We used R to analyze the included data. An initial result showed that the presence of a positive blood alcohol concentration (BAC) had no significant relation with mortality rate (OR = 0.92, 95% CI = 0.83 to 1.01), but there was notable heterogeneity along with variable results according to sensitivity analysis. For the BAC-positive population, low BAC (1 to 100 mg/dl) carried a higher risk of mortality than moderate BAC (100 to 230 mg/dl) (OR = 1.40, 95% CI = 1.09 to 1.81), moderate and high BAC as a single category (>100 mg/dl) (OR = 1.57, 95% CI = 1.28 to 1.94), or high BAC (>230 mg/dl) (OR = 1.76, 95% CI = 1.34 to 2.30). However, moderate BAC did not increase the mortality risk when compared with high BAC (OR = 1.20, 95% CI = 0.89 to 1.63). Whether positive BAC at the time of admission after TBI reduces mortality rate compared with the rate under negative BAC remains unknown. In addition, low BAC (1 to 100 mg/dl) poses a risk of mortality compared with higher BAC. Further studies assessing the effect of alcohol between the BAC-positive group and the BAC-negative group are still needed.

Recall bias across 7 days in self-reported alcohol consumption prior to injury among emergency department patients

INTRODUCTION AND AIMS

Recall bias is a concern in self-reported alcohol consumption, potentially accounting for varying risk estimates for injury in emergency department (ED) studies. The likelihood of reporting drinking for the same 6-h period each day of the week for a full week preceding the injury event is analysed among injured ED patients.

DESIGN AND METHODS

Probability samples of patients 18 years old and older were interviewed in two ED sites in Vancouver and one in Victoria, BC (n = 1191). Generalized estimating equation modelling was used to predict the likelihood of reporting drinking for the same 6-h period prior to the injury event for each day of the week, compared to day 7 as the reference recall day, for a full week preceding the event. Recall by frequency of drinking and frequency of heavy drinking was analysed.

RESULTS

Drinking was significantly more likely to be reported for each of the first 3 days of recall compared to 7-day recall and highest for 1-day recall (odds ration 1.55; = 0.002). Patients who reported ≥ weekly drinking and 5+ drinking < monthly were significantly more likely to report drinking for each of the first 3 days of recall (compared to 7-day recall).

DISCUSSION

Findings suggest the first 3 days prior to injury may be a less biased multiple-matched control period than longer periods of recall in case-crossover studies.

CONCLUSION

Length of accurate recall may be important to consider in case-crossover analysis and other study designs that rely on patient self-report such as the Timeline Followback. [Cherpitel CJ, Ye Y, Stockwell T, Vallance K, Chow C. Recall bias across 7 days in self-reported alcohol consumption prior to injury among emergency department patients.

Risk of injury from alcohol, marijuana and other drug use among emergency department patients

BACKGROUND

Alcohol is known to be associated with injury, but little is known of combined use of alcohol and other drugs on injury; especially important for marijuana, given increasing legalization of use in the U.S. and Canada.

METHODS

Probability samples of patients 18 and older were interviewed in the emergency department at two sites in Vancouver and one in Victoria, BC (n=1191 injured and 1613 non-injured patients). Case-control and case-crossover analyses were used to analyze risk of injury, based on self-reported alcohol and drug use (marijuana, stimulants, depressants) prior to injury.

RESULTS

Risk of injury was significantly elevated (p<0.001) for alcohol use alone in both case-control (OR=2.72) and case-crossover analyses (OR=2.80) but not for any of the three drug classes. The interaction of alcohol with each class of drug was tested, and marginally significant only for marijuana in case-control analysis (OR=4.42; p=0.088). The interaction of alcohol and two or more drugs was also significant in case-control analysis (OR=03; p=0.035). The volume of alcohol consumed prior to injury was greater for those also using drugs during this time and positively associated with the number of drugs reported.

CONCLUSION

Given the potential issues involved with both case-control and case-crossover study designs, the inconsistent findings suggest caution in reaching any definite conclusion regarding whether there is extra risk related to combined use of alcohol and marijuana, and is an important area for future research.

What triggers an episode of acute low back pain? A case-crossover study

OBJECTIVE

To investigate a range of transient risk factors for an episode of sudden-onset, acute low back pain (LBP).

METHODS

This case-crossover study recruited 999 subjects with a new episode of acute LBP between October 2011 and November 2012 from 300 primary care clinics in Sydney, Australia. Each participant was asked to report exposure to 12 putative triggers over the 96 hours preceding the onset of back pain. Conditional logistic regression was used to estimate odds ratios (ORs) expressing the magnitude of increased risk with exposure to each trigger.

RESULTS

Exposure to a range of physical and psychosocial triggers significantly increased the risk of a new onset of LBP; ORs ranged from 2.7 (moderate or vigorous physical activity) to 25.0 (distracted during an activity or task). Age moderated the effect of exposure to heavy loads and sexual activity. The ORs for heavy loads for people ages 20, 40, or 60 years were 13.6, 6.0, and 2.7, respectively. The risk of developing back pain was greatest between 7:00 AM and noon.

CONCLUSION

Transient exposure to a number of modifiable physical and psychosocial triggers substantially increases risk for a new episode of LBP. Triggers previously evaluated in occupational injury studies, but never in LBP, have been shown to significantly increase risk. These results aid our understanding of the causes of LBP and can inform the development of new prevention approaches.

Differences in risk of injury in the U.S. general population by injury treatment type: data from the 1995 to 2010 national alcohol surveys

BACKGROUND

While emergency room (ER) studies have documented a strong association of alcohol with injury, these studies are not necessarily representative of the general population. To evaluate comparative risk of injury from drinking for those treated in the ER with non-ER-treated injuries (those treated elsewhere or those not treated), data on alcohol and injury are analyzed in the U.S. general population by type of injury treatment.

METHODS

Relative risk (RR) of injury from drinking within 6 hours prior to the event was analyzed using case-crossover analysis based on respondents' usual frequency of drinking in 4 (1995 to 2010) National Alcohol Surveys (n = 4,819).

RESULTS

RR was 1.01 for the total injured and significantly elevated for ER-treated injured (1.46), but not for those treated elsewhere (0.75) and those not treated (1.02). RR was significantly elevated for those aged 18 to 30 years (1.45; 1.14, 1.85), Blacks (1.54; 1.11, 2.14) and Hispanics (1.98; 1.51, 2.59), those positive on the Rapid Alcohol Problems Screen (RAPS4) as a measure of alcohol dependence (2.41; 1.86, 3.11), and for motor vehicle injuries (2.61; 1.49, 4.58) or cutting/piercing injuries (2.04, 1.10, 3.81). For those reporting ER-treated injuries, significant effect modification was found for those aged 18 to 30 years (RR = 2.29), Blacks (RR = 2.59) and Hispanics (RR = 2.68), high risk-taking (RR = 1.71), positive RAPS4 (RR = 3.69), and for motor vehicle (RR = 3.79) and cutting/piercing injuries (RR = 2.60).

CONCLUSIONS

Data suggest alcohol plays a larger role in injuries for which ER treatment is sought than for other injuries, and estimates for injury from drinking derived from ER studies may be elevated. Future general population studies should take into account intensity of exposure to alcohol prior to injury, potential recall bias (by eliciting data on the proximity of injury to time of the respondent interview) and severity of injury, for improving estimates of the attributable burden of alcohol to injury in society.

Risk of injury from drinking: the difference which study design makes

BACKGROUND

The magnitude of risk of injury from drinking, based on emergency department (ED) studies, has been found to vary considerably across studies, and the impact of study design on this variation is unknown.

METHODS

Patients were interviewed regarding drinking within 6 hours prior to the injury or illness event, drinking during the same time the previous week, and usual drinking during the last 30 days. Risk estimates were derived from case-control analysis and from both pair-matched and usual frequency case-crossover analysis.

RESULTS

The odds ratio (OR) based on case-control (2.7; 1.9 to 3.8) was larger than that based on pair-matched case-crossover analysis (1.6; 1.0 to 2.6). The control-crossover estimate suggested the case-crossover estimate was an underestimate of risk, and when this adjustment was applied to the case-crossover estimate, risk of injury increased (OR = 3.2; 1.7 to 6.0). Adjusted case-crossover estimates compared with unadjusted showed the largest proportional increase at 7 or more drinks prior to injury (OR = 7.1; 2.2 to 22.9). The case-crossover estimate based on usual frequency of drinking was substantially larger (OR = 10.7; 8.0 to 14.3) than that based on case-control or pair-matched case-crossover analysis, but less than either when adjusted based on control-crossover usual frequency analysis (OR = 2.2; 1.5 to 3.3).

CONCLUSIONS

The data suggest that while risk of injury based on case-control analysis may be biased, control data are important in providing adjustments derived from control-crossover analysis to case-crossover estimates, and are most important at higher levels of consumption prior to the event.

Risk of injury due to alcohol: evaluating potential bias using the case-crossover usual-frequency method

BACKGROUND

The usual-frequency case-crossover method, comparing exposure before an event with typical exposure of the same person, is widely used to estimate the risk of injury related to acute alcohol use. Prior results suggest that risk estimates might be biased upward compared with other methods.

METHODS

Using data from 15 emergency room studies in seven countries, we compared the usual-frequency case-crossover method with case-control analysis, using noninjury patients as controls. Control-crossover analysis was performed to examine potential bias and to adjust risk estimates.

RESULTS

The cross-study pooled odds ratio (OR) of injury related to drinking was 4.7 (95% confidence interval = 2.6-8.5) in case-crossover analysis and 2.1 (1.6-2.7) in case-control analysis. A control-crossover analysis found an indication of bias (OR = 2.2 [1.8-2.8]), which was larger among less-frequent drinkers.

CONCLUSION

Findings suggest that the potential overestimation of injury risk based on the usual-frequency case-crossover method might be best explained by recall bias in usual-frequency estimates.

Alcohol as a trigger for medical emergencies

In this paper, our goal is to report relative risks of the impact of alcohol consumption 6 hours prior to medical emergencies presenting in the emergency department for 8,346 patients in seven countries using data from the Emergency Room Collaborative Alcohol Analysis Project. We found that alcohol increased the risk of a medical emergency by 2.17 times (confidence interval: 1.78-2.65), and those without a regular pattern of heavy drinking and those younger showed a greater risk. Acute alcohol is associated not only with injury but also with medical emergencies. More studies are needed on the acute role of alcohol in medical emergencies, preferably with data on the type of medical emergencies.

Evaluating recall bias in a case-crossover design estimating risk of injury related to alcohol: data from six countries

INTRODUCTION AND AIMS

Prior work suggests that recall bias may be a threat to the validity of relative risk estimation of injury due to alcohol consumption, when the case-crossover method is used based on drinking during the same six hours period the week prior to injury as the control period. This work explores the issue of alcohol recall bias used in the case-crossover design.

DESIGN AND METHODS

Data were collected on injury patients from emergency room studies across six countries (Dominican Republic, Guatemala, Guyana, Nicaragua, Panama and Canada), conducted in 2009-2011, each with n ≈ 500 except Canada (n = 249). Recall bias was evaluated comparing drinking during two control periods: the same six hours period the day before versus the week before injury.

RESULTS

A greater likelihood of drinking yesterday compared with last week was seen using data from the Dominican Republic, while lower likelihood of drinking yesterday was found in Guatemala and Nicaragua. When the data from all six countries were combined, no differential drinking between the two control periods was observed.

DISCUSSION AND CONCLUSIONS

These findings are in contrast to earlier studies showing a downward recall bias of drinking, and suggest that it may be premature to dismiss the last week case-crossover method as a valid approach to estimating risk of injury related to drinking. However, the heterogeneity across countries suggests that there may be some unexplained measurement error beyond random sampling error.

D, de Bradshaw AM. Risk of injury after alcohol consumption from case-crossover studies in five countries from the Americas

AIMS

This study aimed to: (i) provide relative risk (RR) estimates between acute alcohol use and injuries from emergency departments (EDs) in the Dominican Republic, Guatemala, Guyana, Nicaragua and Panama, and (ii) test whether the RR differs if two control periods for the estimates were used.

DESIGN

Case-crossover methodology was used to obtain estimates of the RR of having an injury within 6 hours after drinking alcohol, using a pair-matching design with control periods of the same time of day on the day prior to injury, and the same time of day and day of week during the week prior to injury.

SETTING

EDs.

PARTICIPANTS

A total of 2503 injured patients from EDs were interviewed between 2010 and 2011, with a response rate of 92.6%.

MEASUREMENTS

Number of drinks consumed within 6 hours prior to the injury and in the two control periods.

FINDINGS

The RR of injury after drinking alcohol was 4.38 [95% confidence interval (CI): 3.29-5.84] using the prior week as the control period, and 5.35 (CI: 3.50-8.17) using the prior day as a control period. The RR was 5.08 (CI: 4.15-6.23) in multiple matching. Those drinking one to two drinks had a RR of 4.85 (CI: 3.12-7.54); those drinking three to five drinks an RR of 5.00 (CI: 3.47-7.18); those drinking six to 15 drinks an RR of 4.54 (CI: 3.36-6.14); and those drinking 16 or more drinks an RR of 10.42 (CI: 4.38-24.79).

CONCLUSIONS

As in other countries, drinking alcohol is an important trigger for an injury in the Dominican Republic, Guatemala, Guyana, Nicaragua and Panama.

A systematic review and meta-analysis of alcohol consumption and injury risk as a function of study design and recall period

BACKGROUND

It is well established that alcohol consumption is associated with an increased risk of injury. This systematic review and meta-analysis addresses important methodological issues commonly encountered in the alcohol and injury field by delineating the effect of study design and alcohol consumption recall period on effect size magnitude and by conducting gender-specific analyses.

METHODS

We performed meta-analyses using random-effect models. Data sources were peer-reviewed studies on alcohol and injury from 1970 to 2009 from MEDLINE, PsychInfo, and on-line journals. Case-control or case-crossover emergency department (ED) studies reporting injury risk from alcohol consumption 6 hours before injury were included.

RESULTS

The overall odds of injury were 2.799 (2.214 to 3.538, p < 0.001). For case-crossover studies, the odds were 3.815 (2.646 to 5.499, p < 0.001); for ED case-control studies, the odds were 1.977 (1.385 to 2.821, p < 0.001); and for population case-control designs, the odds were 3.145 (1.583 to 6.247, p < 0.005). The "usual frequency" recall period yielded an odds ratio of 4.235 (2.541 to 7.057, p < 0.001), compared to 2.320 (1.789 to 3.008, p < 0.001) for all other methods. There were significant differences in odds ratio magnitude when comparing studies by design and recall period. Females had higher odds of injury than males, 2.285 (1.361 to 3.836, p < 0.005) versus 1.071 (0.715 to 1.605, p = 0.737).

CONCLUSIONS

Study design and alcohol consumption recall period have significant effects on effect size magnitude in estimating the risk of injury from alcohol consumption 6 hours prior to injury. For the "usual frequency" case-crossover design, significant moderator effects were found, resulting in overestimates of injury risk from alcohol. ED case-crossover designs tend to overestimate risk, and ED case-control designs tend to underestimate. We provide recommendations for future ED research.

Alcohol and risk of admission to hospital for unintentional cutting or piercing injuries at home: a population-based case-crossover study

Background

Cutting and piercing injuries are among the leading causes of unintentional injury morbidity in developed countries. In New Zealand, cutting and piercing are second only to falls as the most frequent cause of unintentional home injuries resulting in admissions to hospital among people aged 20 to 64 years. Alcohol intake is known to be associated with many other types of injury. We used a case-crossover study to investigate the role of acute alcohol use (i.e., drinking during the previous 6 h) in unintentional cutting or piercing injuries at home.

Methods

A population-based case-crossover study was conducted. We identified all people aged 20 to 64 years, resident in one of three regions of the country (Greater Auckland, Waikato and Otago), who were admitted to public hospital within 48 h of an unintentional non-occupational cutting or piercing injury sustained at home (theirs or another's) from August 2008 to December 2009. The main exposure of interest was use of alcohol in the 6-hour period before the injury occurred and the corresponding time intervals 24 h before, and 1 week before, the injury. Other information was collected on known and potential confounders. Information was obtained during face-to-face interviews with cases, and through review of their medical charts.

Results

Of the 356 participants, 71% were male, and a third sustained injuries from contact with glass. After adjustment for other paired exposures, the odds ratio for injury after consuming 1 to 3 standard drinks of alcohol during the 6-hour period before the injury (compared to the day before), compared to none, was 1.77 (95% confidence interval 0.84 to 3.74), and for four or more drinks was 8.68 (95% confidence interval 3.11 to 24.3). Smokers had higher alcohol-related risks than non-smokers.

Conclusions

Alcohol consumption increases the odds of unintentional cutting or piercing injury occurring at home and this risk increases with higher levels of drinking.

Hospital-admitted injury attributable to alcohol

BACKGROUND

Primary data collection has established that alcohol causes injuries treated in the emergency department. No comparable data exist for injuries admitted to hospital. Data on the injury risks of heavy drinkers relative to other drinkers also are sparse.

METHODS

We estimated (i) whether regular heavy drinkers have higher hospitalized injury risks than other people when alcohol-negative and (ii) how much hospitalized injury risk of regular heavy drinkers and other drinkers rises when alcohol-positive. We combined national alcohol consumption data with alcohol metabolism rates to estimate hours spent alcohol-positive versus alcohol-negative during a year for heavy drinkers versus other people. A literature review provided hospitalized nonfatal injury rates for these groups by alcohol involvement.

RESULTS

Relative to other alcohol-negative people aged 18 and older, heavy drinkers have an estimated relative risk of hospitalized injury of 1.4 when alcohol-negative and 4.3 when alcohol-positive. Others have an estimated relative risk of 1.0 when alcohol-negative and 6.8 when alcohol-positive. Thus, alcohol greatly raises injury risk. The excess risk patterns persist for a wide range of sensitivity analysis values. Of hospitalized injuries, an estimated 21% are alcohol-attributable including 36% of assaults.

CONCLUSIONS

Drinking alcohol is a major cause of hospitalized injury. Heavy drinkers lead risky lifestyles. They tolerate alcohol better than most drinkers, but their injury risks still triple when they drink. Our approach to attribution is a valuable complement to more costly, more precise approaches that rely heavily on primary data collection. It works for any severity of injury. Applying it only requires an existing alcohol consumption survey plus data on alcohol involvement in targeted injuries.

Psychoactive medications and crash involvement requiring hospitalization for older drivers: a population-based study

OBJECTIVES

To determine the association between psychoactive medications and crash risk in drivers aged 60 and older.

DESIGN

Retrospective population-based case-crossover study.

SETTING

A database study that linked the Western Australian Hospital Morbidity Data System and the Pharmaceutical Benefits Scheme.

PARTICIPANTS

Six hundred sixteen individuals aged 60 and older who were hospitalized as the result of a motor vehicle crash between 2002 and 2008 in Western Australia.

MEASUREMENTS

Hospitalization after a motor vehicle crash.

RESULTS

Greater risk for a hospitalization crash was found for older drivers prescribed benzodiazepines (odds ratio (OR)=5.3, 95% confidence interval (CI)=3.6-7.8, P<.001), antidepressants (OR=1.8, 95% CI=1.0-3.3, P=.04), and opioid analgesics (OR=1.5, 95% CI=1.0-2.3, P=.05). Crash risk was significantly greater in men prescribed a benzodiazepine (OR=6.2, 95% CI=3.2-12.2, P<.001) or an antidepressant (OR=2.7, 95% CI=1.1-6.9, P=.03). Women prescribed benzodiazepines (OR=4.9, 95% CI=3.1-7.8, P<.001) or opioid analgesics (OR=1.8, 95% CI=1.1-3.0, P=.03) also had a significantly greater crash risk. Subgroup analyses further suggested that drivers with (OR=4.0, 95% CI=2.9-8.1, P<.001) and without (OR=6.0, 95% CI=3.8-9.5, P<.001) a chronic condition who were prescribed benzodiazepines were at greater crash risk. Drivers with a chronic condition taking antidepressants (OR=3.4, 95% CI=1.3-8.5, P=.01) also had a greater crash risk.

CONCLUSION

Psychoactive medication usage was associated with greater risk of a motor vehicle crash requiring hospitalization in older drivers.

Risk of injury from alcohol and drug use in the emergency department: a case-crossover study

INTRODUCTION AND AIMS

A substantial literature exists demonstrating the risk of injury from alcohol, but less is known about the association of alcohol in combination with other drugs and injury. This study examined the risk of injury associated with alcohol and drug use prior to the event.

DESIGN AND METHODS

Case-crossover analysis was used to estimate the relative risk (RR) of injury due to alcohol use alone, compared with alcohol in combination with other drug use in a sample of emergency department injured patients from two sites in Vancouver, British Columbia (n = 443). Alcohol and drug use in the 6 h prior to injury was compared with the patient's use of these substances during the same 6 h period the day prior and the week prior to injury.

RESULTS

Using multiple matching for the two control time periods, RR of injury was significantly related to both alcohol use (RR = 3.3) and to alcohol combined with drug use (RR = 3.0), but not to drug use alone. Effect modification was found only for age for alcohol combined with drug use, with a significant increase in injury risk (P = 0.087) for those over 30.

DISCUSSION AND CONCLUSION

While a similar elevated risk of injury was found for alcohol use alone and alcohol used with other drugs, the literature suggests that alcohol in combination with some drugs may be potentially more risky for injury occurrence. Findings suggest the need for future research on risk of injury for specific alcohol and drug combinations.

Inverse relationship between moderate alcohol intake and rectal cancer: analysis of the North Carolina Colon Cancer Study

BACKGROUND

The relationship between alcohol intake and rectal cancer is uncertain.

OBJECTIVE

We sought to evaluate whether alcohol consumption is associated with distal colorectal cancer and rectal cancer specifically.

DESIGN

Data on alcohol intake were examined from the North Carolina Colon Cancer Study, a population-based case-control study of distal colorectal cancer.

SETTING

This study encompassed 33 counties in the central and eastern part of North Carolina.

PATIENTS

Cases had adenocarcinoma of the rectum, rectosigmoid, and sigmoid colon. Controls were frequency-matched on age, race, and sex.

INTERVENTIONS

Demographic and dietary intake data were collected with use of a validated questionnaire.

MAIN OUTCOME MEASURES

Logistic regression was used to estimate odds ratios for the relationship between alcohol consumption and distal colorectal cancer.

RESULTS

Included in the study were 1033 cases and 1011 controls. The odds ratio for rectal cancer comparing any vs no alcohol intake was 0.73 (95% CI 0.60, 0.90), adjusted for age, sex, race, smoking status, obesity, education, red meat intake, use of nonsteroidal anti-inflammatory medications, and family history of colorectal cancer. The odds ratio for moderate alcohol (≤14 g/day) was 0.66 (95% CI 0.53, 0.82), whereas the odds ratio for heavy alcohol (>14 g/day) was 0.93 (95% CI 0.70, 1.23). Moderate beer and wine intakes were also inversely associated with distal colorectal cancer: odds ratios 0.76 (95% CI 0.60, 0.96) and 0.69 (95% CI 0.56, 0.86).

LIMITATIONS

This was a retrospective, observational study. Residual confounding is possible.

CONCLUSIONS

In this study, moderate alcohol intake (especially wine) was inversely associated with distal colorectal cancer.

The more you drink, the harder you fall: a systematic review and meta-analysis of how acute alcohol consumption and injury or collision risk increase together

Alcohol consumption causes injury in a dose-response manner. The most common mode of sustaining an alcohol-attributable injury is from a single occasion of acute alcohol consumption, but much of the injury literature employs usual consumption habits to assess risk instead. An analysis of the acute dose-response relationship between alcohol and injury is warranted to generate single occasion- and dose-specific relative risks. A systematic literature review and meta-analysis was conducted to fill this gap. Linear and best-fit first-order model were used to model the data. Usual tests of heterogeneity and publication bias were run. Separate meta-analyses were run for motor vehicle and non-motor vehicle injuries, as well as case-control and case-crossover studies. The risk of injury increases non-linearly with increasing alcohol consumption. For motor vehicle accidents, the odds ratio increases by 1.24 (95% CI: 1.18-1.31) per 10-g in pure alcohol increase to 52.0 (95% CI: 34.50-78.28) at 120 g. For non-motor vehicle injury, the OR increases by 1.30 (95% CI: 1.26-1.34) to an OR of 24.2 at 140 g (95% CI: 16.2-36.2). Case-crossover studies of non-MVA injury result in overall higher risks than case-control studies and the per-drink increase in odds of injury was highest for intentional injury, at 1.38 (95% CI: 1.22-1.55). Efforts to reduce drinking both on an individual level and a population level are important. No level of consumption is safe when driving and less than 2 drinks per occasion should be encouraged to reduce the risk of injury.

The relationship between alcohol consumption and injury in ED trauma patients

BACKGROUND

Alcohol-related injuries are significantly more serious than non-alcohol-related injuries. However, there have been few data on the relationship between alcohol consumption and injury in the Korea. This study was designed to determine the absence or presence of alcohol consumption at the time of injury and the relationship between the quantity of alcohol and the extent of injury.

MATERIALS AND METHODS

The study subjects consisted of trauma patients aged 15 years or older with the emergency department admission at 5 emergency medical centers. With the informed consent, patients were screened using the questionnaire and blood alcohol concentration. The subjects were divided into 2 groups according to the blood alcohol concentration level: the nonintoxicated and intoxicated groups. The demographic characteristics, cause of injury, injury severity, and length of hospitalization were compared between the 2 groups.

RESULTS

Of a total of 407 cases, there were 123 cases in the intoxicated group and 284 cases in the nonintoxicated group. As to the severity of injury, an Abbreviated Injury Scale was significantly higher in the head and face. Injury Severity Score was higher in intoxicated group with marginal statistical significance. There was no significant difference in the total length of hospitalization, but the length of intensive care unit admission was significantly longer in the intoxicated group than in the nonintoxicated group.

CONCLUSION

There may be no significant correlation between alcohol consumption and injury severity. However, injury severity may increase with increasing quantity of alcohol and be greater in head injuries.

A case-crossover study of alcohol consumption, meals and the risk of road traffic crashes

Background

The case-crossover (CC) design has proved effective to investigate the association between alcohol use and injuries in general, but has never been applied to study alcohol use and road traffic crashes (RTCs) specifically. This study aims at investigating the association between alcohol and meal consumption and the risk of RTCs using intrapersonal comparisons of subjects while driving.

Methods

Drivers admitted to an Italian emergency room (ER) after RTCs in 2007 were interviewed about personal, vehicle, and crash characteristics as well as hourly patterns of driving, and alcohol and food intake in the 24 hours before the crash. The odds ratio (OR) of a RTC was estimated through a CC, matched pair interval approach. Alcohol and meal consumption 6 and 2 hours before the RTC (case exposure window) were compared with exposures in earlier control windows of analogous length.

Results

Of 574 patients enrolled, 326 (56.8%) reported previous driving from 6 to 18 hours before the RTC and were eligible for analysis. The ORs (mutually adjusted) were 2.25 (95%CI 1.11-4.57) for alcohol and 0.94 (0.47-1.88) for meals. OR for alcohol was already increased at low (1-2 units) doses - 2.17 (1.03-4.57) and the trend of increase for each unit was significant - 1.64 (95%CI 1.05-2.57). In drivers at fault the OR for alcohol was 21.22 (2.31-194.79). The OR estimate for meal consumption seemed to increase in case of previous sleep deprivation, 2.06 (0.25-17.00).

Conclusion

Each single unit of acute alcohol consumption increases the risk of RTCs, in contrast with the 'legal' threshold allowed in some countries. Meal consumption is not associated with RTCs, but its combined effects with sleepiness need further elucidation.

Emotional stress as a trigger of falls leading to hip or pelvic fracture. Results from the ToFa study - a case-crossover study among elderly people in Stockholm, Sweden

Background

Sudden emotions may interfere with mechanisms for keeping balance among the elderly. The aim of this study is to analyse if emotional stress and specifically feelings of anger, sadness, worries, anxiety or stress, can trigger falls leading to hip or pelvic fracture among autonomous older people.

Methods

The study applied the case-crossover design and was based on data gathered by face to face interviews carried out in Stockholm between November 2004 and January 2006 at the emergency wards of two hospitals. Cases (n = 137) were defined as persons aged 65 and older admitted for at least one night due to a fall-related hip or pelvic fracture (ICD10: S72 or S32) and meeting a series of selection criteria. Results are presented as relative risks with 95% confidence intervals.

Results

There was an increased risk for fall and subsequent hip or pelvic fracture for up to one hour after emotional stress. For anger there was an increased relative risk of 12.2 (95% CI 2.7–54.7), for sadness of 5.7 (95% CI 1.1–28.7), and for stress 20.6 (95% CI 4.5–93.5) compared to periods with no such feelings.

Conclusion

Emotional stress seems to have the potential to trigger falls and subsequent hip or pelvic fracture among autonomous older people. Further studies are needed to clarify how robust the findings are – as the number of exposed cases is small – and the mechanisms behind them – presumably balance and vision impairment in stress situation.

Alcohol and cannabis use as risk factors for injury--a case-crossover analysis in a Swiss hospital emergency department

Background

There is sufficient and consistent evidence that alcohol use is a causal risk factor for injury. For cannabis use, however, there is conflicting evidence; a detrimental dose-response effect of cannabis use on psychomotor and other relevant skills has been found in experimental laboratory studies, while a protective effect of cannabis use has also been found in epidemiological studies.

Methods

Implementation of a case-crossover design study, with a representative sample of injured patients (N = 486; 332 men; 154 women) from the Emergency Department (ED) of the Lausanne University Hospital, which received treatment for different categories of injuries of varying aetiology.

Results

Alcohol use in the six hours prior to injury was associated with a relative risk of 3.00 (C.I.: 1.78, 5.04) compared with no alcohol use, a dose-response relationship also was found. Cannabis use was inversely related to risk of injury (RR: 0.33; C.I.: 0.12, 0.92), also in a dose-response like manner. However, the sample size for people who had used cannabis was small. Simultaneous use of alcohol and cannabis did not show significantly elevated risk.

Conclusion

The most surprising result of our study was the inverse relationship between cannabis use and injury. Possible explanations and underlying mechanisms, such as use in safer environments or more compensatory behavior among cannabis users, were discussed.

The contribution of alcohol to falls at home among working-aged adults

The role of alcohol in the occurrence and burden of fall related injury at home is unclear. We examined the contribution of alcohol to fatal and hospitalized injuries due to unintentional falls at home among working-aged adults. We conducted a population-based case-control study in Auckland, New Zealand between July 2005 and July 2006. Cases were 335 people aged 25-60 years who were admitted to hospital or died as a result of unintentional falls at home. Control subjects were 352 people randomly selected from the electoral roll from the same age band as the cases. The participants or next-of-kin completed a structured interview that ascertained data on sociodemographic, personal, and lifestyle factors including alcohol consumption. After controlling for confounding, the consumption of two or more standard alcoholic drinks in the preceding 6h relative to none was associated with a significantly increased risk of fall related injury (for two standard drinks: odds ratio: 3.7, 95% confidence interval: 1.2-10.9; for three or more drinks: odds ratio: 12.9, 95% confidence interval: 5.2-31.9). Approximately 20% of unintentional falls at home in this population may be attributable to the consumption of two or more alcoholic drinks in the preceding 6h. Drinking is strongly associated with unintentional falls at home that result in admission to hospital or death. Moreover, a substantial proportion of falls at home among working-age people can be attributed to alcohol consumption. This largely unrecognized problem should be addressed in falls prevention programs.

Principal stratification designs to estimate input data missing due to death

We consider studies of cohorts of individuals after a critical event, such as an injury, with the following characteristics. First, the studies are designed to measure "input" variables, which describe the period before the critical event, and to characterize the distribution of the input variables in the cohort. Second, the studies are designed to measure "output" variables, primarily mortality after the critical event, and to characterize the predictive (conditional) distribution of mortality given the input variables in the cohort. Such studies often possess the complication that the input data are missing for those who die shortly after the critical event because the data collection takes place after the event. Standard methods of dealing with the missing inputs, such as imputation or weighting methods based on an assumption of ignorable missingness, are known to be generally invalid when the missingness of inputs is nonignorable, that is, when the distribution of the inputs is different between those who die and those who live. To address this issue, we propose a novel design that obtains and uses information on an additional key variable-a treatment or externally controlled variable, which if set at its "effective" level, could have prevented the death of those who died. We show that the new design can be used to draw valid inferences for the marginal distribution of inputs in the entire cohort, and for the conditional distribution of mortality given the inputs, also in the entire cohort, even under nonignorable missingness. The crucial framework that we use is principal stratification based on the potential outcomes, here mortality under both levels of treatment. We also show using illustrative preliminary injury data that our approach can reveal results that are more reasonable than the results of standard methods, in relatively dramatic ways. Thus, our approach suggests that the routine collection of data on variables that could be used as possible treatments in such studies of inputs and mortality should become common.

Brewing controversies: Darwinian perspective on the adaptive and maladaptive effects of caffeine and ethanol as dietary autonomic modulators

Ethanol and caffeine are two of the oldest human drugs. Their pervasive integration into the modern human diet may reflect behavioral attempts to correct maladaptations induced by evolutionary displacement of the autonomic system. The dietary adoption of caffeine may parallel the emergence of cognition as an independent basis of competition. Enhancement of the cognitive ability to gather and process information likely evolved as a valuable adjunct to physical behavior in prehistoric fight-or-flight encounters. Caffeine effectively exploits this pre-existing association between adrenergic activity and cognitive readiness, leading to its use in the modern environment where success in competition increasingly depends on cognitive, rather than physical, prowess. Ethanol may have emerged as a dietary means to buffer the maladaptive chronic sympathetic activation and fear response associated with stressful lifestyles and the social phobias associated with the dissolution of kin networks. We explore the health implications of ethanol and caffeine use, with particular attention to their acute and chronic effects on the autonomic axis. The putative protective effects of ethanol in surviving major trauma or reducing inflammation and heart disease may relate to tempering the behavioral and cardiovascular consequences of catastrophic or chronic sympathetic activation. Acute or chronic abuse of ethanol manifests paradoxical pro-adrenergic effects such as tremors and insomnia that may partly represent compensatory responses. Compensatory remodeling may also explain why confirmation of detrimental effects related to caffeine-induced sympathetic activation has proven elusive; indeed, paradoxical pro-vagal benefits may eventually be recognized. Ethanol and caffeine are potential agents that may beneficially expand the dynamic range of the autonomic system. In an environment where the Darwinian value of knowledge has increasingly supplanted that of physical traits, the consumption of caffeine and alcohol may represent both a cause and an effect of modern human evolution.

The future of emergency medicine public health research

This chapter addresses past successes and challenges and then elaborates on the potential for further advances in three areas that bridge emergency medicine and the broader public health and health services research agenda: (1) monitoring health care access; (2) surveillance of diseases, injuries, and health risks; and (3) delivering clinical preventive services. This article also suggests ways to advance policy-relevant research on systems of health and social welfare that impact the health of the public.

Acute alcohol use and the risk of non-fatal injury in sixteen countries

AIMS

To determine the relative risk (RR) of non-fatal injury associated with alcohol consumption in a series of emergency departments (EDs), possible effect modifiers and the impact of contextual variables on differences across sites.

DESIGN

The case-crossover method was used to obtain RR estimates of the effect of alcohol on non-fatal injuries. Meta-analysis was used to evaluate the consistency and magnitude of RR across sites, and the extent to which contextual variables explain differences in effect sizes.

PARTICIPANTS

Probability samples of 11,536 injured patients attending 28 EDs studies in 16 countries (1984-2002). The majority of the sample was male (65%) and > 30 years old (53%).

MEASUREMENTS

Exposed cases where those that consumed alcohol 6 hours prior to the injury. Usual alcohol consumption served as the control period.

FINDINGS

Drinking within 6 hours prior to the injury was reported by 21% of the sample. The estimated (random) pooled relative risk for patients who reported alcohol use within 6 hours prior to injury was 5.69 (95% confidence interval = 4.04-8.00), ranging from 1.05 in Canada to 35.00 in South Africa. Effect size was not homogeneous across studies, as societies with riskier consumption patterns had a higher relative risk for injury. Heavier drinkers also showed lower RR.

CONCLUSIONS

Acute alcohol was a risk factor for non-fatal injuries in most sites. Policy measures addressed to the general population are recommended, especially in societies with riskier consumption patterns.

Risk of injury: a case-crossover analysis of injured emergency service patients in poland

BACKGROUND

Over the last 15 years large changes in both alcohol consumption and the health care system have occurred in Poland. Substantial fluctuations in alcohol-related mortality followed and burden on health services increased, but data on risk of injury from alcohol consumption are relatively scarce

METHODS

Estimates for risk of injury from drinking within six hours prior to the event are reported in samples of emergency services patients from Warsaw (n=508) and Sosnowiec (n=432), using case-crossover analysis based on usual frequency of drinking

RESULTS

A four-fold risk of injury was found for those reporting drinking prior to injury compared to those not drinking, and this was significantly greater for those positive for alcohol use disorders compared to those negative. Relative risk of injury was marginally greater in Sosnowiec (5.2) compared to Warsaw (3.4) (p=0.06), and was significantly greater for those under 30. A 17-fold increase in risk for violence-related injury was found, and was significantly greater for females than males. Risk was substantially greater in Sosnowiec compared to Warsaw across all subgroups, but differences were not significant, possibly due to the small numbers of those sustaining injuries from violence in Warsaw.

DISCUSSION

Injury risk related to drinking was expected to be significantly greater in Sosnowiec, due to more traditional drinking styles of infrequent intake of large quantities of spirits, than in Warsaw, but this was only partially borne out by these data. Risk estimates for all injuries were similar to those found in other case-crossover studies in emergency departments. Given the high relative risk estimates for injury related to drinking prior to the event, among both problem and non-problem drinkers, hospital-based emergency services in Poland may be an important site for identification of those who could benefit from a brief intervention or referral for a reduction in alcohol-related injuries.

Alcohol-related hand injuries

The study was based on 1199 patients consecutively treated for hand injuries in the Second Department of Surgery of the Jagiellonian University in Krakow between the years 1987 and 2000. Three hundred and twenty of these patients (26.6%) had consumed alcohol several hours before an accident. Data collected from an interview with the patient and a doctor on duty were used in the study. Routine tests for blood alcohol concentration were not carried out. Young men (89.3%), mostly manual workers (74.3%) (p<0.001), constituted the majority of patients in the alcohol group. They were younger on average (p<0.001) than sober patients. In most cases, the accident had happened at home (65.9%) (p<0.001) and the main cause of injury was a cut with glass (p<0.001). Despite only minor injuries they were treated in hospital due to their state of intoxication. The degree of hand disability was higher (p<0.05) than with sober patients. The average cost of treatment in a state of intoxication was more than twice as high as the cost of treatment in sober patients. Alcohol-related hand injuries present a major medical and socioeconomic problem.

Bullying in the school environment: an injury risk factor?

OBJECTIVE

To describe a research project assessing the role of bullying at school as an injury trigger and the modification effect of the socio-economic environment of the victims. Preliminary results are also presented.

METHOD

A case-crossover and a case-referent design were combined. The study base consisted of all children aged 10-15 years residing in the Stockholm county in 2000-02. Cases were recruited at the county's children hospital and interviewed shortly after the injury, using a specially designed questionnaire.

RESULTS

Preliminary analyses (261 interviews) reveal that about two injured children out of 10 reported having been bullied during the school term. Also, one out of 10 had been bullied shortly enough before the injury for bullying to be considered as a trigger. The circumstances of occurrence of those injuries varied.

CONCLUSION

Bullying, apart from being frequent in the school environment, is quite likely to act as an injury trigger.

Analysis of a potential trigger of an acute illness

Sometimes certain short-term risk exposures are postulated to act as a trigger for the onset of a specific acute illness. When the incidence of the illness is low it is desirable to investigate this possible association using only data on cases detected during a specific observation period. Here we propose an analysis for such a study based on a model expressed in terms of the probability that the exposure triggers the illness and a random delay from a triggered illness until its diagnosis. Both the natural hazard rate for the illness and the probability that the exposure triggers the illness are assumed to be small and possibly dependent on age and covariates such as sex and duration or severity of the exposure. The method of analysis is illustrated with a study of the association between long flights and hospitalization for venous thromboembolism.

Drug and alcohol use among patients admitted to a Danish trauma centre: a prospective study from a regional trauma centre in Scandinavia

OBJECTIVES

The incidence of drug and alcohol use is unknown among Danish trauma patients, and has not been thoroughly investigated in Europe.

METHODS

Patients admitted to the regional trauma centre in Aarhus, Denmark, were prospectively screened by blood and urine tests for the presence of alcohol, and legal and illicit drugs. The correlation with the Injury Severity Score, hospitalization time, and mortality after drug or alcohol intake was investigated.

RESULTS

A quarter of all patients admitted in 1999 and 2000 had an alcohol level exceeding the national legal driving limit of 50 mg/dl, and one or more drugs were found in one in five patients. The presence of any drug or alcohol correlated positively with the Injury Severity Score, whereas alcohol level, hospitalization time, and mortality did not correlate.

CONCLUSION

The rate of trauma patients with a blood serum level of alcohol greater than 100 mg/dl was similar to a previous European study and to US studies. The prevalence of drugs was less, and benzodiazepines were the most used group of drugs in our study. The routine screening of Danish trauma patients in order to implement preventative measures may be beneficial.

Education was associated with injuries requiring hospital admission

OBJECTIVES

We describe educational inequalities in the incidence of injuries resulting in hospital admission and explore the contribution of exposure variables and chronic diseases, alcohol consumption, and sedative use to the observed inequalities.

STUDY DESIGN AND SETTING

Data from the Dutch prospective GLOBE study were linked to the National Hospital Discharge Register after 7 years of follow-up.

RESULTS

Significantly higher hazard ratios (HRs) of traffic injuries in lower compared with higher educational groups were substantially reduced after adjustment for differences in the use of cars and mopeds between these groups. Significantly increased HRs in occupational, home, and sports (OHS) injuries in lower compared with higher educational groups were reduced after adjustment for higher prevalence rates of chronic diseases, very excessive alcohol consumption, and sedative use in lower educational groups.

CONCLUSION

Exposure variables, chronic diseases, alcohol consumption, and sedative use contribute to educational inequalities in traffic and OHS injuries resulting in hospital admission.

Acute alcohol use and suicidal behavior: a review of the literature

BACKGROUND

Both acute and chronic use of alcohol are associated with suicidal behavior. However, the differing relationship of each component of alcohol use and possible causal mechanisms remain unclear.

METHODS

This article reviews and summarizes associations between acute alcohol consumption (with and without intoxication) and suicidal behavior (both completed suicide and suicide attempts) among adults 19 years and older, as presented in literature published between 1991 and 2001. Possible mechanisms and methodologic challenges for evaluating the association are also discussed. An application of a research design (the case-crossover study) that has the potential for addressing the effects of acute alcohol use over and above usual or chronic use is presented.

RESULTS

The majority of articles reviewed were restricted to descriptive studies that documented the prevalence of suicide completers or attempters who tested positive for alcohol use. A wide range of alcohol-positive cases were found for both completed suicide (10-69%) and suicide attempts (10-73%). Common methodologic limitations included the lack of control groups (for evaluating risk conferred by alcohol use), selection and ascertainment bias, and small sample sizes. The results of the case-crossover pilot study indicated substantially higher risk of suicide during or shortly after use of alcohol compared with alcohol-free periods.

CONCLUSIONS

Although there is a substantial literature of published studies on acute alcohol use and suicidal behavior, the majority of studies focus on completed suicide and report prevalence estimates. Findings from such studies are subject to several possible sources of bias and have not advanced our knowledge of mechanisms in the association between acute alcohol use and suicidal behavior. The case-crossover design may help to overcome some limitations of these studies and facilitate evaluation of associations and possible causal mechanisms by which acute alcohol use is linked to suicidal behavior.

Is perceived failure in school performance a trigger of physical injury? A case-crossover study of children in Stockholm County

OBJECTIVES

To investigate whether perceived failure in school performance increases the potential for children to be physically injured.

SUBJECTS

Children aged 10-15 years residing in the Stockholm County and hospitalised or called back for a medical check up because of a physical injury during the school years 2000-2001 and 2001-2002 (n = 592).

METHODS

A case-crossover design was used and information on potential injury triggers was gathered by interview. Information about family socioeconomic circumstances was gathered by a questionnaire filled in by parents during the child interview (response rate 87%).

RESULTS

Perceived failure in school performance has the potential to trigger injury within up to 10 hours subsequent to exposure (relative risk = 2.70; 95% confidence intervals = 1.2 to 5.8). The risk is significantly higher among pre-adolescents and among children from families at a higher education level.

CONCLUSIONS

Experiencing feelings of failure may affect children's physical safety, in particular among pre-adolescents. Possible mechanisms are perceptual deficits and response changes occasioned by the stress experienced after exposure.

The economic impact of payer policies after the Rx-to-OTC switch of second-generation antihistamines

OBJECTIVE

As a result of the over-the-counter (OTC) introduction of loratadine, health plans have been struggling to determine the best policy to incorporate this change within their existing drug benefit structure for second-generation antihistamines (SGA). The objective of this study was to examine the economic impact of payer policies in response to the Rx-to-OTC switch of loratadine.

STUDY DESIGN

Decision analysis was used to model the budgetary impact and cost-effectiveness of four policies for SGA benefits for the managed care organization (MCO), employer, and Medicaid perspectives separately.

PATIENTS AND METHODS

Outcomes included direct medical costs and lost productivity (employers only), discounted, quality-adjusted life-years (QALYs) saved because of amelioration of allergic rhinitis symptoms and avoidance of unintentional injuries associated with the use of first-generation antihistamines (FGA). Bayesian probabilistic sensitivity analysis was conducted using second-order Monte Carlo simulation.

RESULTS

Providing limited OTC and second-tier prescription benefits would cost approximately 0.13 dollars and 0.30 dollars compared to third-tier prescription benefits for employers and MCOs, respectively, and would save Medicaid 0.02 dollars per member per month (PMPM). Providing limited coverage for OTC loratadine while retaining second-tier prescription benefits for SGA was the optimal policy for a willingness to pay below 26,200 dollars per QALY for all payers.

CONCLUSIONS

Offering second-tier prescription and limited OTC benefits provides greater effectiveness and is not significantly more expensive PMPM than discontinuation. Some of the drug savings from limiting coverage of prescription SGA may be attenuated by the cost of lost productivity and direct medical expenditures due to unintentional injuries associated with increased FGA use in addition to the increased cost of therapeutic substitutes.

Risk of injury after alcohol consumption: a case-crossover study in the emergency department

This paper reports a case-crossover analysis in a sample of 961 patients who consulted the emergency department (ED) due to an injury in Santa Clara, California, and in Pachuca, Mexico. In the analysis in which usual alcohol consumption during the last 12 months served as the control value, the estimated relative risk of injury in the hour after alcohol consumption, as compared with no alcohol consumption during that time, was 4.33 (CI, 3.55-5.27). After controlling for alcohol use in the 1-h period before injury, the relative risks for consecutive 1-h periods (2-6 h) before the injury were not significantly greater than one, indicating that the induction time was less than 1 h. The relative risk varied greatly depending on race-ethnicity and acculturation among the Hispanics in Santa Clara, with Mexicans in Pachuca showing the highest risk and the high acculturation group in Santa Clara showing the lowest risk. Violence-related injuries were associated with higher relative risk. Relative risk also varied depending on the presence of alcohol dependence and usual frequency of drunkenness: patients with alcohol dependence and patients with high frequency of usual drunkenness had lower risks than patients without alcohol dependence and with lower self-reported episodes of drunkenness in the last year. When blood alcohol content at ED admission was used instead of self-reported alcohol consumption, similar results were obtained. These findings have important public health consequences. Each episode of alcohol consumption results in an increase in the short-term risk for an injury, especially for a violence-related injury. Patients with the lowest usual involvement with alcohol are subject to a higher elevation in their risk for an injury immediately after alcohol consumption compared to patients who drink more heavily.

Cost-benefit analysis of first-generation antihistamines in the treatment of allergic rhinitis

BACKGROUND

The majority of individuals with allergic rhinitis in the US take first-generation antihistamines (FGAs). Although FGAs have been proven effective in alleviating allergic rhinitis symptoms, they have been associated with an increased risk of motor vehicle, aviation and occupational injuries and deaths, reduced productivity and impaired learning.

OBJECTIVE

The objective of this analysis was to quantify the total costs and benefits of FGA use in the US from the societal perspective.

METHODS

We used a decision-analytic model to quantify the annual societal costs and benefits of treatment with FGAs compared with the hypothetical alternative of no treatment for the population of individuals with allergic rhinitis and taking FGAs in the US in 2001. The benefit associated with FGA use was estimated using the willingness-to-pay framework and projected to the US population using published estimates of the prevalence of allergic rhinitis. The costs of FGA-associated sedation included lost productivity and the direct and indirect cost of unintentional injuries (including motor vehicle, occupational, public and home injuries and fatalities). The incidence of injuries and fatalities associated with FGA use was estimated using the risk of injury attributable to the sedentary effects of FGAs in the allergic rhinitis population. To evaluate uncertainty in the model assumptions, a probabilistic sensitivity analysis was conducted using Bayesian second-order Monte Carlo simulation. Costs and benefits are expressed in 2001 US dollars, using a 3% discount rate.

RESULTS

Based on current utilisation, the total societal benefit (95% credible interval) associated with the use of FGAs for the treatment of allergic rhinitis was US 7.7 billion dollars (US 1.3 billion dollars to US 21 billion dollars). The societal cost of purchasing FGAs was only US 697 million dollars. However, the societal cost of FGA-associated sedation was US 11.3 billion dollars (US 2.4 billion dollars to US 50.8 billion dollars). The annual societal net benefit of FGA use for the treatment of allergic rhinitis in the US was -US4.2 billion dollars (-US 36 billion dollars to +US 0.296 billion dollars). The net benefit was negative in 97% of the 10,000 Monte Carlo simulations.

CONCLUSIONS

The societal benefits of FGA use in alleviating the symptoms of allergic rhinitis are significant. However, based on the assumptions, probability distributions and parameter estimate ranges used in the current model, it is very likely that the costs associated with sedation exceed the benefits of FGA use in the US. The cost of FGA-associated sedation is comparable to estimates of the cost of all medical care expenditures on respiratory conditions in the US (US 12.1 billion dollars to US 31.3 billion dollars) [1996 values] and provides compelling evidence of the economic burden of sedation associated with FGA use.

Interventions for preventing injuries in problem drinkers

BACKGROUND

Alcohol consumption has been linked with injuries through motor vehicle crashes, falls, drowning, fires and burns, and violence. In the US, half of the estimated 100,000 deaths attributed to alcohol each year are due to intentional and unintentional injuries. The identification of effective interventions for the reduction of unintentional and intentional injuries due to problem drinking is, therefore, an important public health goal.

OBJECTIVES

To assess the effect of interventions for problem drinking on subsequent injury risk.

SEARCH STRATEGY

We searched 12 twelve computerized databases: MEDLINE (1966-8/96), EMBASE (1982-1/97), Cochrane Controlled Trials Register (1997, issue #1), PsycINFO (1967-1/97), CINAHL (1982-10/96), ERIC (1966-12/96), Dissertation Abstracts International (1861-11/96), IBSS (1961-1/97), ISTP (1982-1/97) and three specialized transportation databases, using terms for problem drinking combined with terms for controlled trials; bibliographies of relevant trials; and contact with authors and government agencies. The electronic and bibliographic searches were updated in May 2002.

SELECTION CRITERIA

Randomized controlled trials of interventions among participants with problem drinking, which are intended to reduce alcohol consumption or to prevent injuries or their antecedents, and which measured injury-related outcomes.

DATA COLLECTION AND ANALYSIS

Two authors extracted data on participants, interventions, follow-up, allocation concealment, and outcomes, and independently rated allocation concealment quality.

MAIN RESULTS

Of 23 eligible trials identified, 22 had been completed and 17 provided results for relevant outcomes. Completed trials of problem drinkers that compared interventions for problem drinking to no intervention reported reduced motor-vehicle crashes and related injuries, falls, suicide attempts, domestic violence, assaults and child abuse, alcohol-related injuries and injury emergency visits, hospitalizations and deaths. Reductions ranged from 27% to 65%. Because few trials were sufficiently large to assess effects on injuries, individual effect estimates were generally imprecise. We did not combine the results quantitatively because the interventions, patient populations, and outcomes were so diverse. The most commonly evaluated intervention was brief counseling in the clinical setting. This was studied in seven trials, in which injury-related deaths were reduced: relative risk (RR) 0.65; 95% confidence interval (CI) 0.21 to 2.00. However, this reduction may have been due to chance. The majority of trials of brief counseling also showed beneficial effects on diverse non-fatal injury outcomes.

REVIEWERS' CONCLUSIONS

Interventions for problem drinking appear to reduce injuries and their antecedents (e.g. falls, motor vehicle crashes, suicide attempts). Because injuries account for much of the morbidity and mortality from problem drinking, larger studies are warranted to evaluate the effect of treating problem drinking on injuries.

Transitioning the Second-Generation Antihistamines to Over-the-Counter Status

BACKGROUND

A U.S. Food and Drug Administration advisory committee deemed the second-generation antihistamines (SGA) safe for over-the-counter use against the preliminary opposition of the manufacturers. As a result, loratadine is now available over-the-counter. First-generation antihistamines (FGA) are associated with an increased risk of unintentional injuries, fatalities, and reduced productivity. Access to SGA over-the-counter could result in decreased use of FGA, thereby reducing deleterious outcomes. The societal impact of transitioning this class of medications from prescription to over-the-counter status has important policy implications.

OBJECTIVE

To examine the cost-effectiveness of transitioning SGA to over-the-counter status from a societal perspective.

RESEARCH DESIGN

A simulation model of the decision to transition SGA to over-the-counter status was compared with retaining prescription-only status for a hypothetical cohort of individuals with allergic rhinitis in the United States. Estimates of costs and effectiveness were obtained from the medical literature and national surveys. Sensitivity analysis was performed using a second-order Monte Carlo simulation.

MAIN OUTCOME MEASURES

Discounted, quality-adjusted life-years saved as a result of amelioration of allergic rhinitis symptoms and avoidance of motor vehicle, occupational, public and home injuries and fatalities; discounted direct and indirect costs.

RESULTS

Availability of SGA over-the-counter was associated with annual savings of 4 billion dollars (2.4-5.3 billion dollars) or 100 dollars (64-137 dollars) per allergic rhinitis sufferer and 135,061 time-discounted quality-adjusted life years (84,913-191,802). The sensitivity analysis provides evidence in support of these results.

CONCLUSION

Making SGA available over-the-counter is both cost-saving and more effective for society, largely as a result of reduced adverse outcomes associated with FGA-induced sedation. Further study is needed to determine the differential impact on specific vulnerable populations.

Comparison of consumption effects of brief interventions for hazardous drinking elderly

We sought to determine if Brief Interventions [BIs, Motivational Enhancement (ME), and Brief Advice (BA)] reduced alcohol consumption among hazardous alcohol drinking elderly (65 years or older) and whether the elderly responded similarly to younger populations. In 12 primary care offices from October 1995 to December 1997, we screened 13,438 patients of whom 2702 were elderly (180 were hazardous drinkers). Forty-five elderly enrollees were randomized to receive ME (n = 18), BA (n = 12), and Standard Care (SC, n = 12). At baseline, the elderly drank more alcohol and abstained fewer days than the younger cohort (p < 0.05). During the year, the elderly in ME, BA, and SC intervention arms increased the number of days abstained, decreased the number of drinks per day, and reduced the number of total days per month drinking. There were trends toward decreases in the alcohol consumption measures in the ME and BA treatment arms compared to SC. The elderly's response to all interventions was similar to that of the younger cohort. This study suggests that hazardous alcohol consumption in the elderly is common and that BIs reduce alcohol consumption in the elderly similar to younger populations.

Speech shadowing while driving: on the difficulty of splitting attention between eye and ear

We investigated the role of cross-modal links in spatial attention in modulating the efficiency of dual-task performance. The difficulty of combining speech shadowing with a simulated driving task was modulated by the spatial location from which the speech was presented. In both single- and dual-task conditions, participants found it significantly easier to shadow one of two auditory streams when the relevant speech was presented from directly in front of them, rather than from the side. This frontal speech advantage was more pronounced when participants performed the demanding simulated driving task at the same time as shadowing than when they performed the shadowing task alone. These results demonstrate that people process auditory information more efficiently (with a lower overall dual-task decrement) when relevant auditory and visual stimuli are presented from the same, rather than different, spatial locations. These results are related to recent findings showing that there are extensive cross-modal links in spatial attention, and have clear implications for the design of better user interfaces.

Alcohol intoxication increases morbidity in drivers involved in motor vehicle accidents

We prospectively examined the correlation of alcohol intoxication with injury severity, morbidity, and mortality in drivers involved in motor vehicle accidents in a prospective cohort study. The study enrolled 923 injured patients, of whom 421 were legally intoxicated (blood alcohol concentration [BAC] > or = 50 mg/dL) and 502 were not intoxicated (BAC < 50 mg/dL). The intoxicated drivers had a significantly higher injury severity score (ISS), lower Glasgow Coma Score, lower systolic blood pressure; higher rate in old age, male sex, greater rate of habitual drinking, greater lack of use of safety gear, and greater accident-related morbidity. After logistic regression analysis, alcohol intoxication was not associated with severe injury (ISS > or = 9); however, alcohol intoxication analyzed either as a preinjury or postinjury risk factor, was one of the predictors for morbidity. Severe head injury was the only predictor of mortality. In conclusion, although alcohol intoxication is not associated with an increased incidence of severe injury or mortality in drivers involved in motor vehicle crashes, it is one of the significant predictors for morbidity after injury.