Presentation mekong conference

RISK OF ROAD TRAFFIC INJURY RISK OF ROAD TRAFFIC INJURY AFTER ALCOHOL CONSUMPTION AFTER ALCOHOL CONSUMPTION

IN VIETNAMIN VIETNAM

Hue, August 2010

Dr. Nguyen Minh Tam

Prof. Michael Dunne

Prof. Ross Young

A/Prof. Peter Hill

A/Prof. Pham Van Linh

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Drink-Driving Worldwide

• Road traffic injury - A major global public health problem• 1.27 million deaths & 50 million injured worldwide a year

• Road traffic injury - A burden for developing countries• 91% of all road traffic deaths & 91.8% of DALYs world wide

• Drinking and driving is a major road safety problem but continues to receive inadequate attention– High income countries

• Declines in drink-driving recently plateaued or begun rising • 20% road traffic deaths having BAC > legal limit

– Low and middle income countries• 33-69% road traffic deaths having BAC > legal limit• Underestimates due to lacking of data

! Lack of data from poorest regions underestimate the ‘true size’ of the problem

Odero W. (1997); WHO report (2004); World Bank (2006)

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Drink-Driving Worldwide

• Alcohol increases the risk of RTI– Even small amount of alcohol consumption increases risk of RTI– Risk elevates significantly from a BAC level of 0.04 g/dl– Wide ranges (2 - 64 fold) from different estimates

• Alcohol increases the severity of RTI• ↑ deaths and post-trauma disabilities• ↑ hospital care

• Lack of research less is known about the magnitude of the role of alcohol in RTI in developing countries

! Lack of evidence of ‘good practice’ political will

Draus A. (2008), Gururaj G. (2004), Odero W. (1997); WB (2006); WHO (2004)

Road Traffic in Vietnam

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• Dec 2009:

29 million registered motor vehicles,

95% are motorcycles

• 8,000 newly registered motorcycles a day

• > 3,000 injured per day

58 deaths daily due to RTI

National Traffic Safety Committee (2010); VMIS (2002)

Drinking in Vietnam

• Significant increase in alcohol consumption– Consumption increased 52% in five year period

• per capita: 12.4 litres (2003) to 17.7 litres (2008)

• Change in drinking patterns – Drinking at bar and restaurants is “part of a highly

desirable social life”

• Consumption of alcohol to continue growing– Economy continues to progress well

– Higher disposable incomes and modern lifestyles5

Euromonitor (2009)

Drinking and driving in Vietnam

• Drink-driving law• Legal limit: BAC 0.08% 0.05% (1st July 09)

• Official data and community surveys: very low rate of alcohol involvement in RTI

• 6% (NTSC report) - 7.3% (HSPI household survey)

• Hospital data provide a much higher prevalence of alcohol related traffic injuries

• 33.4% (2 hospitals in Hanoi) - 34% (NFMI study) (blood sample test)

• Little surveillance not possible to estimate ‘true size’ of the problem

6National Traffic Safety Committee (2008), Health Strategy and Policy Institute (2009), National Forensic Medicine Institute (2003), Thuong et al. (2009)

Objective & Conceptual Framework

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Objective: To identify the risk of traffic injury after alcohol consumption among patients with recent traffic injuries in the ED

Methodological considerations – the case-crossover design and analysis

8Maclure M (Am J Epidemiol 1991), Maclure M & Mittleman MA. (Ann Rev of Public Health 2000)

Case-crossover analysis

Event: Traffic InjuryExposure: Acute Alcohol ConsumptionLength of the exposure effect: 6 hoursHazard period: 6 hours before traffic injury onset

Control dataThe drinking information from a 6 hour period at the same time same day in the prior week of the onset of traffic injury

UnexposedExposed

Unexposed

Exposed

Control Period

HazardPeriod

OR = b/c

Maclure M (Am J Epidemiol 1991), Redelmeier DA, Tibshirani RJ. (New Eng J Med 1997), Gullette EC, et al. (JAMA 1997), Meier CR, et al. (Lancet 1998), Barbone F, et al. (Lancet 1998), Borges G, et al. (Soc Sci Med 2004)

Aug 8 Aug 1

RESULTS RESULTS

Sample

• Study at Emergency Department– 1012 male patients admitted to the ED with injuries

– 676 were traffic related injured patients (66.8%)

– 196 patients could not provide breath analysis and complete interview

• ventilated/resuscitated (9), • too severely injured (77), confused (13), • too intoxicated to cooperate (16), other reasons (20)

– 61 did not provide consent

– Final sample: 480 male traffic injured patients

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BAC levels of patients with recent RTI

BAC Levels (g/dL) Frequency Percent Cumulative %0 168 35.0 35.0

0.001 – 0.049 22 4.6 39.6

0.05 – 0.079 14 2.9 42.5

0.08 – 0.149 57 11.9 54.4

0.15+ 219 45.6 100.0

Total 480 100.0

BAC levels of patients with recent RTI

WHO: 8-29%; South Africa: 26 - 31%; India: 33%; Thailand: 36 - 44%

BAC Levels (g/dL) Frequency Percent Cumulative %0 168 35.0 35.0

0.001 – 0.049 22 4.6 39.6

0.05 – 0.079 14 2.9 42.5

0.08 – 0.149 57 11.9 54.4

0.15+ 219 45.6 100.0

Total 480 100.0

No. of drinks consumed in 6h prior to injuries

No. of drinks consumed at control time (same time

same day previous week) OR 95% CI

p

0 1 2-3 4-5 ≥ 6

0 133 5 9 5 5 1

1 4 1 1 1 0 0.80 0.18 – 3.41 1.000

2 - 3 66 2 11 3 3 7.33 3.54 – 15.75 <0.001

4 – 5 44 2 7 6 2 8.80 3.35 – 25.19 <0.001

≥ 6 67 1 9 1 26 13.40 5.20 – 37.69 <0.001OR (drank/not drank) = 8.9 (95% CI = 5.10 – 15.39)

Risk of traffic injuries by number of drinks consumed

Implications of the study

• Implications for policy– Call for the strengthening of enforcement along with

media campaigns and news coverage– Addressing the inconsistency between legal BAC for

drivers of motorcycles compared to cars– A more strategic and comprehensive approach to

alcohol policy in Vietnam.

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Implications of the study

• Implications for injury prevention– Educational programs to raise awareness of

drinkers and community on drink-driving• Education on responsible drinking and beverage

service• Encourage people not to drive to drinking events • Encouraging alternative transport both to and from

the venue

– Promote the local motorbike taxis (“xe om”) • Popular, cheap fares and widespread availability• Warnings about the safety 16

Implications of the study

• Implications for further study– Case-crossover design as an appropriate method to

estimate the risk of traffic injury after alcohol use• Eliminating interpersonal confounding• Pair-matching: more powerful than group-matching • Saving time and cost feasibility

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CONCLUSIONS

• The first study of its kind in Vietnam– Combination of systematic collection of breath test and

use of case-crossover design

provide convincing evidence on the magnitude of alcohol related traffic injuries

inform the formulation of interventions to reduce drinking and driving in Vietnam and other developing countries

• Urgent need of a multi-sector approach to curtail drink-driving in Vietnam, especially programs to raise community awareness and effective legal enforcement.

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We can all do something to help…

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… people to change

Acknowledgement

• My dear supervisors: Prof. Michael Dunne, Prof. Ross Young, A/Prof. Peter Hill, A/Prof. Pham Van Linh

• Hue College of Medicine and Pharmacy• Queensland University of Technology• My beloved family• Colleagues in Vietnam• Participants in the study• Grants:

– N.M.T. is a PhD. student in the QUT-Vietnam Public Health Project supported by the Atlantic Philanthropies.

– the Atlantic Philanthropies through the VINE Project. – the Bloomberg Philanthropies through the World Health Organization – the World Bank through the Road Traffic Injury Research Network.

Thank you!

Study at ED

Time frame: - 17.00hrs to 7.00hrs

the next day

- 7 days a week

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Patients with recent traffic injuries n (%) p valuePedestrian Car driver Motorcycle /

bicycle driver Passenger

Age (Mean ± SD) 43.33± 20.551

30.75± 8.593

30.78± 11.593

26.71± 9.987

<0.001

Income (Mean ± SD)(in multiples of Vietnamese minimum annual wage of US $ 410 [190])

3.19± 1.424

3.44± 1.236

3.30± 1.335

2.91± 1.571

0.583

Education level 0.772

Secondary school or lower 10(52.6%)

3(27.3%)

158(40.6%)

14(48.2%)

High school 6(31.6%)

6(54.5%)

147(37.5%)

9(31.0%)

College/University 3(15.8%)

2(18.2%)

86(21.9%)

6(20.7%)

Marital status 0.286

Single 8(40.0%)

7(61.5%)

209(52.6%)

20(66.7%)

Married 12(60.0%)

5(38.5%)

189(47.4%)

10(33.3%)

Employment status 0.306

No 4(19.0%)

1(7.7%)

67(17.2%)

9(29.0%)

Yes 17(81.0%)

11(92.3%)

327(82.8%)

22(71.0%)

Alcohol dependent(AUDIT-C)

0.229

No 5(41.7%)

3(37.5%)

159(49.8%)

16(69.6%)

Yes 7(58.3%)

5(62.5%)

160(50.2%)

7(30.4%)

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Research Variables & Analysis PlanM

ain

Stu

dy Case-crossover Design

A scientific way to ask and answer the question that “Was the patient doing

anything unusual just before the onset of the disease?”

A design that compares the exposure to certain agent during the interval when the event does not occur (control period), to

the exposure during the interval when the event occurs (hazard period)

Case-crossover design is used when a brief exposure causes a transient change in risk

of an acute onset event

Objective 1: To estimate the risk of traffic injuries after alcohol consumption

 Blood Alcohol Concentration (g/dL)

Patrons Patients p value

No. % No. %

0.00 – 0.049 62 13.3 190 39.6<0.0001

0.05 – 0.079 47 10.1 14 2.90.08 – 0.149 171 36.9 57 11.9≥ 0.15 184 39.7 219 45.6Total 464 100 480 100

Number and % having BAC over 0.08% 355 76.6 276 57.5 <0.0001

Number and % having BAC over 0.05% 402 86.7 290 60.4 <0.0001

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BAC level of patrons and patients