Trends in Sexual Risk Behavior and Unprotected Sex among High School Students, 1991-2005: The Role of Substance Use

Article excerpt

Adolescents who engage in substance use or risky sexual behaviors are at an increased risk for adverse health outcomes, including human immunodeficiency virus and other sexually transmitted diseases (STDs). (1,2) Use of illicit drugs and alcohol has been found to be strongly associated with sexual risk behaviors among adolescents and young adults. (3-6) Previous research has suggested that substance users (including users of alcohol and illicit drugs) are more likely than nonusers to engage in risky sexual behavior and that they are less likely than nonusers to rely on condoms. (4,6-10) Students who reported using marijuana, cocaine, and other illicit drugs have been found to be more likely than nonusers to report having had sexual intercourse, having had 4 or more sexual partners, and having not used a condom at last sexual intercourse. (4) Healthy People 2010 includes goals focusing on decreasing youths' involvement in drugs and alcohol and on reducing risky sexual behaviors. (11)

National data show widespread substance use among adolescents. (12-14) According to the 2005 Youth Risk Behavior Surveillance (YRBS) survey, 43.3% of youth reported current use of alcohol, 74.3% reported lifetime use, and 25.5% reported episodic heavy drinking. (12) Data from the most recent National Survey on Drug Use and Health indicate that nearly 10% of 12- to 17-year-old youths reported current illicit drug use. (14) National surveys (including the YRBS) have also measured drug and alcohol use trends in youth over the past 15 years. (12-14) Levels of alcohol use were relatively stable during the early to mid-1990s; lifetime alcohol use and current alcohol use have decreased since 1999, and episodic alcohol use has decreased since 1997. (12) Reported use of drugs such as cocaine and marijuana increased during the 1990s and peaked in 1999 but has since decreased. (12) Data from the school-based survey Monitoring the Future show a trend in increasing use of illicit drugs from 1991 to 1996. (13) The prevalence rates for most drugs leveled off in 1997 and began declining by 1998. By 2005, lifetime illicit drug use including marijuana was reported by 38% of 12th graders. (13)

Teen sexual behavior reported on surveys has undergone substantial change in the period 1991-2005. According to the YRBS, the percentage of high school students who reported having had sexual intercourse declined steadily after 1991. (12) Reported condom use during most recent sexual intercourse has increased among high school students (2,12,15) from 46.2% in 1991 to 62.8% in 2005. (2) A similar increase in dual use of contraception (use of condom and hormonal contraception) was also reported from 1991 to 2001. (16) These trends in the YRBS data are supported by similar trends in declining sexual experience and increasing contraceptive use between 1995 and 2002 observed in another national survey, the National Survey of Family Growth. (17)

Previous research has not examined trends in sexual behavior that take into account the simultaneous role of substance use and how substance use and sexual behavior have interacted over time. To determine the trends in sexual activity among substance-using youth, we examined data on drug and alcohol use and sexual activity from YRBS surveys conducted over the past 15 years. This analysis is the first to consider the 2 risk behaviors simultaneously. The YRBS offers many advantages for evaluating trends in health behaviors of adolescents that are not available from other data systems, specifically nationally representative data on sexual behavior and substance use measured at several time points during the period.

METHOD

Sample

The YRBS has been conducted in alternating years (1991, 1993, 1995, 1997, 1999, 2001, 2003, and 2005), and each YRBS survey has been designed as an independent, nationally representative sample of 9th- to 12th-grade students in the United States. Samples ranging from 10,904 to 16,262 students were collected in each of the 8 surveys, and overall response rates were 60-70%. …