Unit 12 epidemiology substance abuse

The Epidemiology of Substance Disorders

Measures

Lifetime prevalence: The proportion of a sample that has ever

experienced a given disorder at sometime in their life (up to their age at study)

12-month prevalence: The proportion of a sample that has experienced

a given disorder in the 12 months preceding the study

Age of onset

Lifetime Prevalence of Substance Disorders by Age (NCS-R Sample)

Total (%)

18-29 (%)

30-44 (%)

45-59 (%)

60+

Alcohol abuse 13.2 14.3 16.3 14.0 6.2

Alcohol dependence 5.4 6.3 6.4 6.0 2.2

Drug abuse 7.9 10.9 11.9 6.5 0.3

Drug dependence 3.0 3.9 4.9 2.3 0.2

Any substance disorder 14.6 16.7 18.0 15.3 6.3

Source: Kessler RC et al. Lifetime prevalence and age-of-onset distributions of DSM-IV disorders in the National Comorbidity Survey Replication. Arch Gen Psychiatry 62:593-602.

Total (%) Serious (%)

Moderate (%)

Mild (%)

Alcohol abuse 3.1 28.9 39.7 31.5

Alcohol dependence 1.3 34.3 65.7 0.0

Drug abuse 1.4 36.6 30.4 33.0

Drug dependence 0.4 56.5 43.5 0.0

Any substance disorder 8.9 32.9 52.4 14.7

Source: Kessler RC et al. Lifetime prevalence and age-of-onset distributions of DSM-IV disorders in the National Comorbidity Survey Replication. Arch Gen Psychiatry 62:593-602.

Twelve-Month Prevalence of Substance Disorders by Severity (NCS-R Sample)

Alcohol Abuse/Dependence

Alcohol Abuse/Dependence: Other Epidemiologic Data Sources

Alcohol Epidemiologic Data System Monitors data from the National Hospital Discharge

Survey for discharges due to alcohol diagnoses Random sample from nonfederal short-stay hospitals 1997: 1.8% listed “alcohol dependence syndrome” as

primary diagnosis; another 0.5% had an alcohol abuse diagnosis

Higher rates for men than women Highest in ages 15-44 years

Epidemiologic Catchment Area (ECA) study 5 U.S. sites 13.8% lifetime prevalence; 6.3% 12-month prevalence

Source: Day NL, Homish GG, The epidemiology of alcohol use, abuse, and dependence. In: Textbook in Psychiatric Epidemiology, MT Tsuang and M. Tohen (eds.), 2nd edition. New York: Wiley-Liss, Inc., 2002.

Alcohol Abuse/Dependence: Age of Onset (AOO)

Median age of onset: 21 (ECA study) 90% of all subjects experienced first symptom

before age 38


Risk Factors Associated with Alcohol Abuse and Dependence

Race: Hispanics and African-Americans are more likely to have a diagnosis of alcoholism within the past month Caucasians have a higher overall prevalence than

African-Americans, but this depends on age At younger ages, prevalence is higher in Caucasians; at

older ages, prevalence is higher in African-Americans (NHIS survey)

Separated or divorced have higher rates than married or single people

Family history of alcoholism (risk increased 7-fold)


Alcohol Abuse/Dependence: Comorbid Conditions

Most common second diagnosis: drug abuse and dependence (ECA study) Anxiety disorders may be the most common second

diagnosis in women (NCS study)

Antisocial personalityManiaSchizophreniaFemales have the highest rates of

comorbidity


Drug Abuse/Dependence

Incidence of Drug Abuse / Dependence

Cumulative annual incidence of 1.09% (drug abuse and dependence) (ECA study) ~40% drug abuse without dependence ~60% drug dependence with or without drug abuse

Source: Anthony JC, Helzer JE, Epidemiology of drug dependence. In: Textbook in Psychiatric Epidemiology, MT Tsuang and M. Tohen (eds.), 2nd edition. New York: Wiley-Liss, Inc., 2002.

Risk Factors for Drug Abuse/Dependence

MaleAge 15-25 yearsFamily history of drug abuse/dependenceChildhood misbehavior and aggression

Hyperactivity, attentional difficulties Association with deviant peers

Source: Anthony JC, Helzer JE, Epidemiology of drug dependence. In: Textbook in Psychiatric Epidemiology, MT Tsuang and M. Tohen (eds.), 2nd edition. New York: Wiley-Liss, Inc., 2002.

Health & Medicine

Unit 12 epidemiology substance abuse