1. Drinking practices and problems in adolescents: Evidence from female and male twins K. K. Bucholz, Ph.D, S.A. Ryan, M.S.P.A., P.A.F. Madden, Ph.D., A.C. Heath, D.Phil. Missouri Alcoholism Research Center Support of AA11998, AA12640, DA12450 and AA09022 is gratefully acknowledged

2. OBJECTIVE To compare drinking practices and problems reported by adolescent and young adult female and male twins who participated in the Missouri Adolescent Female Twin Study (MOAFTS) from 1995 to 1999, and the MARC/Genetic Epidemiology of Smoking study (males) which is ongoing

3. METHODS Male and female twins ascertained from state vital health statistics, born 1975 -1986 (females) and 1982-1991 (males) All twins were interviewed by telephone with a structured psychiatric diagnostic interview with an alcohol section that covered drinking milestones, current and lifetime drinking practices, and alcohol problems consistent with DSM-IV alcohol abuse/dependence Analyses are limited to those aged 14 or older who were regular drinkers –Females: 781/2256 –Males: 505/915

4. ALCOHOL USE LEVELS BY AGE (%) 14-1516-1819+ Females N (736)(886)(634) Lifelong abstainers 55.834.116.3 Infrequent/light drinkers*31.731.523.1 Drinkers12.534.460.6 MalesN (98)(340)(477) Lifelong abstainers 61.238.812.6 Infrequent/light drinkers** 20.424.711.3 Drinkers 18.436.576.1 * Never had at least 3 drinks on a single occasion, or drank fewer than 6 days ever in lifetime **Never drank regularly AND never been intoxicated

5. DRINKING MILESTONES AGE GROUP:14-1516-1819+ Age first drinkF13.214.615.5 M12.114.215.9 Age first regular drinkingF14.015.717.2 M13.916.117.9 Age first intoxicationF14.015.216.4 M13.515.317.1 Maximum drinks, last 12 mo.F9.98.89.1 M7.28.711.4 Maximum drinks, lifetimeF11.510.010.8 M13.215.218.2

6. PERCENT CONSUMING 5+ DRINKS IN A SINGLE DAY IN THE LAST YEAR, BY GENDER AND AGE % 5+ monthly% at least once Age:

7. PERCENT DRINKING TO INTOXICATION IN THE LAST YEAR,BY GENDER AND AGE % at least monthly% at least once in last year Age:

8. PATHOLOGICAL DRINKING INDICATORS AGE GROUP:14-15(%)16-18(%)19+(%) Became drunk when didn’t want to F16.315.717.4 M22.211.315.7 Drank more than meant to/drank moreF50.047.246.6 days in a rowM41.238.543.6 Great deal of time spent drinkingF17.416.111.8 M17.610.714.2 BlackoutsF43.440.535.8 M41.229.5*34.8 Tried to quit but couldn’tF5.45.31.9 M5.92.4 2.6 Wanted to quit/cut downF32.627.920.6 M41.222.319.5 * p<.05

9. SOCIAL/LEGAL PROBLEMS AGE GROUP:14-15(%)16-18(%)19+(%) Serious family problemsF4.411.26.6 M17.6*3.3**11.1* Physical fightsF15.29.511.8 M29.417.2*22.5*** Said mean things thatF23.329.329.0 wouldn’t have otherwiseM29.420.531.6 ArrestedF01.01.3 M06.4***6.4*** Accident when drinkingF8.75.24.7 M22.211.3*7.8 * p<.05, ** p<.01, *** p<.001

10. RISK TAKING BEHAVIORS AGE GROUP: 14-15(%)16-18(%)19+(%) Drove when had a F011.223.9 lot to drink M6.217.236.3*** Charged with DUI F000.8 M07.94.4 Rode with drunk driverF37.839.344.1 M27.824.2**41.6 Drank in situation where F22.821.033.9 could have been hurtM11.87.6***15.1*** Took other risksF1.14.35.0 M11.1*5.78.7* * p<.05, ** p<.01, *** p<.001

11. HEALTH & PSYCHOLOGICAL PROBLEMS AGE GROUP: 14-15(%)16-18(%)19+(%) Drinking led to: HealthF01.31.8 problemsM001.1 Drinking worsened healthF2.21.63.7 M002.0 Drinking caused F14.116.718.0 depressed feelings M11.88.2*10.0** Drinking caused feelingsF23.110.06.9 of paranoiaM17.66.63.4* Drinking caused trouble F2.24.33.6 thinking clearlyM23.5***4.15.7 Drinking causedF † -5.02.4 memory problemsM-4.25.4* † Not asked in younger girls, * p<.05, ** p<.01, *** p<.001

12. INTERFERENCE WITH RESPONSIBILITIES AGE GROUP: 14-15(%)16-18(%)19+(%) Cut down on activitiesF6.66.34.2 M5.94.13.4 Often missed school F5.45.63.9 M02.55.7 Poor work/ schoolF7.65.33.7 performanceM17.65.74.0 Suspended from schoolF2.20.71.0 M01.61.7 Drinking interfered withF14.18.811.0 other responsibilities M17.610.78.8

13. SELF-PERCEIVED PROBLEMS AGE GROUP: 14-15(%)16-18(%)19+(%) Felt guilty about drinkingF47.245.441.5 M52.930.3**30.2** Felt drank too much F14.113.811.6 M16.76.4*10.6 Felt had drinking problem † F10.214.68.5 M22.24.8*13.7 Had 2+ problemsF54.451.853.9 M50.050.050.7 Had 3+ problemsF021.026.8 M33.3***30.0*25.3 † Conditional item, asked only of those with 2 or more problems. * p<.05, ** p<.01, *** p<.001

14. CONCLUSIONS - I Our data show a strong age effect for prevalence of drinking for both females and males. There are sharp increases in regular drinkers from 14-15 age cohort to 19+ age cohort. The male-female gap in drinking amounts widens with age Drinking to intoxication is common across all age groups, with higher monthly rates in males than in females The most common problems in both males and females were risk taking behaviors and heavy drinking indicators

15. CONCLUSIONS-II The proportions of youth who reported experiencing adverse consequences relating to their daily routines, school work, or job performance were modest The proportion reporting adverse physical health consequences from drinking was also low Unlike physical problems, adverse psychological problems from drinking were more common. Feeling depressed due to drinking was more common among females than among males

16. CONCLUSIONS –III A high percentage of drinkers aged 14-15 reported wanting to quit, compared to proportions in older cohorts. Even so, one fifth of older drinkers wanted to quit or cut down. Certain problems were more common in males, such as ever being arrested, driving a car after drinking a lot, and fighting. A higher proportion of females across the 2 older age groups compared to their male counterparts reported feeling guilty about drinking

17. CONCLUSIONS-IV Half of both female and male age cohorts had 2 or more alcohol problems One third of boys aged 14-15 and 16-18 had 3 or more problems, which was significantly elevated over the proportion observed in females. However, by the 19+ age cohort, the proportion of male and female drinkers having 3+ problems was equivalent. Despite the high proportion with problem drinking, very few believed that they had a drinking problem, with only modest percentages of females (8.5%=14.5%)and males (4.8% - 22.2%) endorsing this.

18. DRINKING PRACTICES % drinking to intoxication, at least monthly % drinking to intoxication, ever in last 12 months AGE Age:

19. DRINKING PRACTICES – LAST YEAR Age: % drinking at least once a month % having 5+ drinks in a day, ever in last year