Older Driver and Occupant Older Driver and Occupant SafetySafety

Gerald McGwin, Jr., M.S., Ph.D.Gerald McGwin, Jr., M.S., Ph.D.

Departments of Epidemiology, Ophthalmology Departments of Epidemiology, Ophthalmology

and Surgeryand Surgery

University of Alabama at BirminghamUniversity of Alabama at Birmingham

Crash Rate DecompositionCrash Rate Decomposition

SOURCE: Dellinger AM, et al. AJE; 2002SOURCE: Dellinger AM, et al. AJE; 2002

Crash Rate DecompositionCrash Rate Decomposition

SOURCE: Dellinger AM, et al. AJE; 2002SOURCE: Dellinger AM, et al. AJE; 2002

Prevention EffortsPrevention Efforts

• Interventions tend to focus on primary Interventions tend to focus on primary prevention.prevention.

Crash Rate DecompositionCrash Rate Decomposition

SOURCE: Dellinger AM, et al. AJE; 2002SOURCE: Dellinger AM, et al. AJE; 2002

Mean Daily Minutes and Miles Spent Mean Daily Minutes and Miles Spent Driving by Driver AgeDriving by Driver Age

National Household Travel Survey, 2001U.S. Department of Transportation

Prevention EffortsPrevention Efforts

• Interventions tend to focus on primary Interventions tend to focus on primary prevention.prevention.

• These interventions either demonstrate These interventions either demonstrate small, significant effects, lack evaluation or small, significant effects, lack evaluation or have not impacted crash involvement.have not impacted crash involvement.

• Studies evaluating secondary and tertiary Studies evaluating secondary and tertiary prevention rareprevention rare

Crash Rate DecompositionCrash Rate Decomposition

SOURCE: Dellinger AM, et al. AJE; 2002SOURCE: Dellinger AM, et al. AJE; 2002

Older Driver “Older Driver “FragilityFragility””

Opportunities for Reducing FatalitiesOpportunities for Reducing Fatalities

Older Driver FragilityOlder Driver Fragility

Increased Susceptibility to Injury

0.00

5.00

10.00

15.00

20.00

25.00

Inju

ry R

ate

(per

10,

000

Cra

sh I

nvo

lved

Occ

up

ants

)

0 - 09 10 - 19 20 - 29 30 - 39 40 - 49 50 - 59 60 - 69 70 - 79 80+

Older Driver FragilityOlder Driver Fragility

Who is at Risk?

Older Driver FragilityOlder Driver Fragility

Secondary Prevention Opportunities

Older Occupant ProtectionOlder Occupant Protection

•Seat belts are most effective means of reducing Seat belts are most effective means of reducing risk of injury and fatality from MVCs. risk of injury and fatality from MVCs.

•Some research suggests that seat belts may be Some research suggests that seat belts may be less effective among older drivers. less effective among older drivers.

•Air bags have been shown to offer trivial Air bags have been shown to offer trivial benefits in preventing injury and death. benefits in preventing injury and death.

•They can be harmful to small children; whether They can be harmful to small children; whether they provide equivalent protection for adults of they provide equivalent protection for adults of all ages, however, has not been addressed. all ages, however, has not been addressed.

Risk Ratios* and 95% Confidence Intervals for Risk Ratios* and 95% Confidence Intervals for Association Between Association Between Severe InjurySevere Injury and and

Seat Belt UseSeat Belt Use According to Age According to Age

*Adjusted for age, gender, delta-v, curb weight, seating position, air bag deployment*Adjusted for age, gender, delta-v, curb weight, seating position, air bag deployment

0.0

0.2

0.4

0.6

0.8

<36 36-65 >65

Ris

k R

ati

o

pphomogeneityhomogeneity=0.15=0.15

Risk Ratios* and 95% Confidence Intervals for Risk Ratios* and 95% Confidence Intervals for Association Between Association Between Moderate InjuryModerate Injury and and

Seat Belt UseSeat Belt Use According to Age According to Age

*Adjusted for age, gender, delta-v, curb weight, seating position, air bag deployment*Adjusted for age, gender, delta-v, curb weight, seating position, air bag deployment

0.0

0.2

0.4

0.6

0.8

<36 36-65 >65

Ris

k R

ati

o

pphomogeneityhomogeneity=0.23=0.23

Risk Ratios* and 95% Confidence Intervals for Risk Ratios* and 95% Confidence Intervals for Association Between Association Between Minor InjuryMinor Injury and and

Seat Belt UseSeat Belt Use According to Age According to Age

*Adjusted for age, gender, delta-v, curb weight, seating position, air bag deployment*Adjusted for age, gender, delta-v, curb weight, seating position, air bag deployment

0.0

0.2

0.4

0.6

0.8

1.0

1.2

<36 36-65 >65

Ris

k R

ati

o

pphomogeneityhomogeneity=0.26=0.26

Risk Ratios* and 95% Confidence Intervals for Risk Ratios* and 95% Confidence Intervals for Association Between Association Between Severe InjurySevere Injury and and Air Bag Deployment Air Bag Deployment According to AgeAccording to Age

*Adjusted for age, gender, delta-v, curb weight, seating position, air bag deployment*Adjusted for age, gender, delta-v, curb weight, seating position, air bag deployment

0.0

0.5

1.0

1.5

2.0

2.5

<36 36-65 >65

Ris

k R

ati

o

pphomogeneityhomogeneity=0.40=0.40

Risk Ratios* and 95% Confidence Intervals for Risk Ratios* and 95% Confidence Intervals for Association Between Association Between Moderate InjuryModerate Injury and and

Air Bag Deployment Air Bag Deployment According to AgeAccording to Age

*Adjusted for age, gender, delta-v, curb weight, seating position, air bag deployment*Adjusted for age, gender, delta-v, curb weight, seating position, air bag deployment

0.0

0.5

1.0

1.5

2.0

2.5

3.0

<36 36-65 >65

Ris

k R

ati

o

pphomogeneityhomogeneity=0.61=0.61

Risk Ratios* and 95% Confidence Intervals for Risk Ratios* and 95% Confidence Intervals for Association Between Association Between Minor InjuryMinor Injury and and Air Bag DeploymentAir Bag Deployment According to Age According to Age

*Adjusted for age, gender, delta-v, curb weight, seating position, air bag deployment*Adjusted for age, gender, delta-v, curb weight, seating position, air bag deployment

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

<36 36-65 >65

Ris

k R

ati

o

pphomogeneityhomogeneity=0.004=0.004

Older Driver FragilityOlder Driver Fragility

Long Term Consequences

SummarySummary

• Increased susceptibility to injury/death Increased susceptibility to injury/death among older drivers underscores need for among older drivers underscores need for primary prevention efforts.primary prevention efforts.

• Reduced effectiveness of air bags for Reduced effectiveness of air bags for older drivers suggests the need for older drivers suggests the need for restraint systems tailored towards aging restraint systems tailored towards aging population.population.

Older Driver and Occupant Older Driver and Occupant SafetySafety

Gerald McGwin, Jr., M.S., Ph.D.Gerald McGwin, Jr., M.S., Ph.D.

Departments of Epidemiology, Ophthalmology Departments of Epidemiology, Ophthalmology

and Surgeryand Surgery

University of Alabama at BirminghamUniversity of Alabama at Birmingham