Epidemiology of Addiction

Transcription

1 Epidemiology of Addiction M.-L. Brecht UCLA Integrated Substance Abuse Programs California Society of Addiction Medicine Review Course Oct. 24, 2008

2 The presenter has no conflicts related to this material.

3 Topics Definitions Tools/measurement Examples of incidence & prevalence of substance use/addiction Risk factors

4 Epidemiology Study of the distribution and determinants of health-related status/events in specified populations (or patterns and causes of disease occurrence)

5 Uses Public policy/community health (who, what, where, when, cost/benefit) Prevention Treatment Research Etiology Risk factors Health services & treatment outcomes Clinical practice Individual decisions

6 Basic Definitions Incidence occurrence of new cases of disease Example: approximately 2.1 million people in the U.S. aged 12 and older initiated marijuana use in 2007

7 Prevalence a measure of disease status, cases of disease at a specific time or during a specific period Example: in 2007, 10% of people in the U.S. aged 12 or older had used marijuana in the past year

8 Basic Measurement Numbers 10 of the 50 high school boys in Smalltown USA used marijuana for the first time during the past year Rates # per grouping unit, e.g. the rate in KS in 1992 for admissions to treatment for methamphetamine use was < 5 per 100,000 population aged 12 or older Probability & percent (special type of rate, per 100).25 of h.s. boys in Smalltown used mj for the first time during the past year [.20= 10/50 ] or 20% of h.s. boys. [ 20%= (10/50)x100 ]

9 Measures of Association Relative risk (RR) or risk ratio: comparison of risk of disease in 2 populations (ratio of 2 rates or probabilities) Example: RR of marijuana incidence in 2006 in Smalltown for h.s. boys compared to girls was 2.0 (probability of mj boys) (probability of mj girls) (10/50) (8/80) = 2.0

10 Measures of Association, cont. Odds ratio (OR): comparison (ratio) of odds of disease Example: OR for boys mj initiation compared to girls was 2.25 or boys had more than double the odds of mj initiation than girls (odds mj for boys) (odds mj for girls) odds for boys: 10 to 40 [of total 50: 10 yes, 40 no] odds for girls: 8 to 72 [of total 80: 8 yes, 72 no] OR = (10/40) (8/72) = 2.25

11 Types of Epidemiologic Studies Experimental Clinical trials Field trials (incl. community intervention & cluster randomized) Non-experimental (observational) Cohort vs. case control Prospective vs. retrospective

12 Computing & Reporting Incidence/Prevalence of Substance Use/Disorder Requires details on what, who, when, & how many: Case definition Specific substance or class of drugs Severity of use/problems (e.g., use, abuse, dependence) Incidence or prevalence Time period (e.g. lifetime, past year, past month)

13 Computing & Reporting, cont. Population definition General population vs. specific (e.g. admissions to treatment, calls to Poison Control Centers) Subgroups covered (e.g. age, ethnicity, gender, criminal justice) Geography Relevant calculations & units (numbers, %, rates, measures of association, etc.) Good data (e.g., recent, reliable/valid)

14 Examples of Data Sources General U.S. population annual: National Survey on Drug Use & Health (NSDUH), BRFSS; periodic: NESARC, National Comorbidity Study General U.S. youth population -- Monitoring the Future, Youth Risk Behavior Survey Treatment admissions TEDS Workplace drug testing programs Law enforcement/criminal justice Mortality stats, poison control, medical examiners & ER episodes (DAWN), prescription drug sales

15 More Detail on Two National Prevalence/Incidence Surveys NSDUH NESARC Survey conducted annually , Sample size* 67,870 43,093 Response rate* 74% 81% Age range 12 & older 18 & older *details reported for 2007 NSDUH and NESARC

16 Substance Use/Abuse Prevalence & Incidence May Differ by.. Demographic & personal characteristics, e.g. Gender Ethnicity Age Family history (e.g. parent substance abuse) Employment Marital status Education Psychological comorbidity Criminal history

17 Substance Use/Abuse Prevalence & Incidence May Differ, cont. And also by, e.g. Geography Geo/social characteristics (e.g. neighborhood crime, pop.density, SES, etc.) Calendar time Substance/Drug (and measures differ by data source & case definition details)

18 Prevalence: Alcohol/Drug* Use by Time Period (lifetime, past yr., past mo.) & Abuse/Dependence Percent Alcohol Any Drug Marijuana Cocaine Psycho therapeutics Lifetime use Past year use Past month use Past yr. abuse/dep * Term drug (also labeled illicit drug ) includes any illicit drug or non-medical use of prescription-type psychotherapeutics (narcotic pain-relievers, tranquilizers, stimulants, sedatives) Source: SAMHSA Office of Applied Studies, 2007 NSDUH

19 Past Year Prevalence of Substance Use Disorders (NSDUH 2007, aged 12 & older) Alcohol 7.5% Drug 2.8% Marijuana 1.6% Cocaine 0.6% Heroin 0.1% Psychotherapeutics* 0.9% * non-medical use of prescription pain relievers, tranquilizers, stimulants, sedatives

20 Prevalence of Substance Use Disorders (NESARC , aged 18 & older) Past Yr Lifetime Alcohol 8.5% 30.3% Drug 2.0% 10.3% Marijuana 1.5% 8.5% Cocaine 0.3% 2.8% Opioids 0.4% 1.4% Source: NESARC as reported in Hasin et al., 2007 & Compton et al., 2007

21 Risk Factors: Gender Past yr. prevalence of selected substance disorders (NSDUH, 2006, 2007*, age 12 & older) 12 % with disorder Males Females 2 0 Alcohol Any drug Marijuana Cocaine Pain relievers Stimulants *Prevalence for Alcohol and Any Drug from 2007, specific drugs from 2006 NSDUH

22 Risk Factors: Gender Approximate Relative Risk, male to female, for prevalence of selected substance disorders (NSDUH 2006, 2007, age 12 & older) Past yr. substance disorder (2007) Alcohol 2.3 to 1 (RR=2.3) Drugs 2 to 1 (RR=2) Past yr. disorders for specific drugs (from 2006) Marijuana 2 to 1 (RR=2) Cocaine 2 to 1 (RR=2.5) Pain relievers 1.3 to 1 (RR=1.3) Stimulants 1 to 1 (RR=1)

23 Risk Factors: Age Past yr. prevalence of substance disorders (NSDUH, 2006) Drug Alcohol % with drug disorder % with alcohol disorder > >64

24 Risk Factors: Age Prevalence of past year substance disorders (NSDUH 2007, age 12 & older) Drug Alcohol years 4% 5% years 8% 17% 26 & older 2% 6% Source: SAMHSA Office of Applied Studies, NSDUH, 2007

25 Risk Factors: Ethnicity Prevalence of past year substance disorders (NSDUH 2007, age 12 & older, selected ethnic groups) Drug Alcohol Non-Hispanic white 3% 8% Hispanic 3% 7% African-Amer 4% 6% Amer.Ind./Alas.Native 4% 11% Asian 1% 4% Source: SAMHSA Office of Applied Studies, 2007 NSDUH

26 Risk Factor: Employment Past year substance disorders (NSDUH 2007, age 18 & older) Drugs: higher among unemployed (9%) than employed (2% for full-time, 4% for part-time) or not in labor force (2%) Alcohol: higher among unemployed (15%) than employed (9%) or not in labor force (4%) Source: SAMHSA Office of Applied Studies, 2007 NSDUH

27 Risk Factors: Education Past year substance disorders (NSDUH 2007, age 18 & older) Drugs: higher among those with less than high school education (4%) vs. h.s/some college (3%) or college grad (1%) Alcohol: higher among those with some college (9%) vs. hs or less (8%) or college grad (7%) Source: SAMHSA Office of Applied Studies, 2007 NSDUH

28 Risk Factors: Psychological Comorbidity Past yr. prevalence of substance disorders for past yr. comorbid disorder (NSDUH, 2006, age 18 & older) Drug Alcohol % with drug disorder Yes Yes No Yes No Yes 0 No No Depressive disorder Alcohol disorder Depressive disorder Drug disorder % with alcohol disorder E.g. read among those with a past year depressive disorder, 9.3% had a past yr. drug disorder while among those without a depressive disorder only 2% had a drug disorder Source: SAMHSA Office of Applied Studies, 2007 NSDUH

29 Risk Factors: Psychological Comorbidity Odds Ratios* for past year substance disorders (columns) by comorbid disorder (rows) (NESARC , age 18 & older) Drug Alcohol Alcohol Drug Mood Anxiety Personality E.g. read row 3 as the odds of a drug disorder were 3.5 times higher among those with a mood disorder compared to those without a mood disorder * odds ratios adjusted for demographic characteristics. Source: Compton et al., 2007; Hasin et al., 2007

30 Risk Factors: Geographic Past yr. prevalence of substance disorders (NSDUH, 2007, age 12 & older) Drug Alcohol % with drug disorder % with alcohol disorder Pacific Mountain Midwest South Mid- Atlantic New England 0 Pacific Mountain Midwest South Mid- Atlantic Ne w England Source: SAMHSA Office of Applied Studies, 2007 NSDUH

31 Past Month Prevalence: Alcohol/Drug Use & Geography Alcohol use Drug use

32 Risk Factors: Geo/social Past yr. prevalence of substance disorders (NSDUH, 2007, age 12 & older) Drug Alcohol % with drug disorder % with alcohol disorder Large Metro Sm.Metro Non-metro urbanized Nonmetro less urb. Rural 0 Large Metro Sm.Metro Non-metro urbanized Nonmetro less urb. Rural Source: SAMHSA Office of Applied Studies, 2007 NSDUH

33 Primary Amphetamine/Methamphetamine TEDS Admission Rates: (per 100,000 aged 12 and over) < SOURCE: SAMHSA Treatment Episode Data Set (TEDS). 220 or more Incomplete Data 1992

34 Primary Amphetamine/Methamphetamine TEDS Admission Rates: (per 100,000 aged 12 and over) < SOURCE: SAMHSA Treatment Episode Data Set (TEDS). 220 or more 2005 Incomplete Data

35 LA County Treatment Admissions by Primary Substance of Abuse % of all Admissions CADDS CalOMS h2 01- h1 01- h2 02- h1 02- h2 03- h1 03- h2 Alcohol Cocaine/Crack Heroin Marijuana Methamphetamine 04- h1 04- h2 05- h1 05- h2 06- h1 06- h2 07- h1 07- h2 SOURCE: LA ADPA & CA ADP, California Outcome Monitoring System (CalOMS), 2007 (06/h2-07/h2); CADDS (00/h2-06/h1). Note: h1 = first half (January-June); h2 =second half (July-December)

36 LA Co. Treatment Admissions--Gender & Race/Ethnicity, for 5 Most Prevalent Substances, % 100% 80% 80% 60% 60% 40% 40% 20% 20% 0% Alcohol Cocaine Heroin Marij Meth 0% Alcohol Cocaine Heroin Marij Meth Male Female White(n-h) Black Hispanic Other SOURCE: LA County ADP / CA ADP, California Outcome Monitoring System (CalOMS), Note, in 2006 LA County population was 47% Hispanic, 30% non-hisp. White, 10% Black, 13% other.

37 LA Co. Treatment Admissions--Age Group, for 5 Most Frequent Substances % 80% 60% 40% 20% 0% Alcohol Cocaine Heroin Marij Meth < >34 SOURCE: LA County ADP / CA ADP, California Outcome Monitoring System (CalOMS), 2007.

38 SOURCES: WestEd, California Healthy Kids Survey, 6/07. YRBS, online results 6/4/08 Past 30-day Substance Use--Los Angeles County Secondary School Students California Healthy Kids Survey Youth Risk Behavior Study % of Respondents % of Respondents Binge Drinking Cocaine Inhalants LSD/Psychedelics Marijuana Meth Binge Drinking Cocaine Marijuana

39 Resources Websites for specific data sources or summaries from multiple sources Data, documentation, reports: References for slides: Substance Abuse and Mental Health Services Administration, Office of Applied Studies (2008). Results from the 2007 National Survey on Drug Use and Health: National Findings (NSDUH Series H-34, DHHS Publication No. SMA ). Rockville, MD. A. Hughes, et al. (2008) State Estimates of Substance Use from the National Surveys on Drug Use and Health. (DHHS Publication No. SMA , Series H-33). Rockville, MD: Substance Abuse and Mental Health Services Administration, Office of Applied Studies K. Rothman & S. Greenland (1998) Modern Epidemiology. Philadelphia: Lippincott Williams & Wilkins. Compton, W., et al. (2007) Prevalence, correlates, disability, and comorbidity of DSM-IV drug abuse and dependence in the U.S. Archives of General Psychiatry, 64: Hasin, D., et al. (2007) Prevalence, correlates, disability, and comorbidity of DSM-IV drug abuse and dependence in the U.S. Archives of General Psychiatry, 64: Substance abuse reference material, research reports, links to other resources