How Epidemiologists Think About Suicide

Roger B. Trent, Ph.D.EPIC Branch

California Department of Health Services

Public Health Surveillance

• Surveillance--standard data collected consistently over years covering entire populations

• Contrasted with “studies” over a limited time to test a hypothesis

• Emphasis on medical rather than psychologicalaspects

Data on Deaths,Including Suicide

• From standard death certificates used everywhere in the U.S.

• Designed to describe all deaths, so not designed for looking at suicide in particular (e.g., nothing on alcohol, prior attempts)

Hospitalization Data

• In many states, every hospital stay is recorded, so “self-destructive” injuries can be identified

• “Severity” = not fatal, but serious enough to require admission as an in-patient

The Injury Pyramid for Suicide

Fatal (death certificates)

Hospitalized (discharge records)

Out-patient & untreated (self-reports in surveys)

Suicide Rates by Age & Sex, California 1998

0

20

40

60

80

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

Male Female

Attempted Suicide Rates by Age & Sex, California 1998

0102030405060708090

100

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

Male Female

Fatal Methods Used

Guns

Hanging Poison

Other

Nonfatal Methods Used

Poison

Cut/pierce

HangOther

Method Affects Lethality

Method Fatal Hosp. % Fatal

Gun 1,661 145 92

Hanging 692 203 77

Poison 544 12,338 4

Cut/pierce 58 2,219 3

Other 256 770 25

Some Unanswered Questions

• Prevention vary by age?

• Prevention vary by gender?

• Strength of intent a factor in method choice?

• Availability a factor in method choice?

Conclusions

• Public Health: Illuminate the patterns• Put in context with other health issues• Identify groups at risk in the population

Surveillance + Hypothesis testing studies+ Clinical experience

Basis for policy