Drug and Alcohol Dependence 76S (2004) S53–S67 The development of suicide ideation and attempts: an epidemiologic study of first graders followed into young adulthood Holly C. Wilcox a,b,* , James C. Anthony b,c a Department of Psychiatry and Behavioral Sciences, Center for Family Research, George Washington University, Washington DC, WA 20037, USA b Department of Mental Health, Bloomberg School of Public Health, Johns Hopkins University, 624 N Broadway, 8th FL, Baltimore, Maryland, MD, USA c Department of Epidemiology, College of Human Medicine, Michigan State University, East Lansing, MI 48823, USA Received 8 July 2004; accepted 4 August 2004 Abstract Studying community residing youths originally recruited for an intervention trial upon entry into first grade, this project sought to estimate risk of suicide ideation and attempts to young adulthood, with focus on those who used drugs before age 16, as compared to youths who used later in development or not at all. Standardized interview assessments in 1989–1994 were completed with 2311 youths age 8–15. Roughly 15 years after recruitment, our study team reassessed 1695, nearly 75% of the survivors (mean age = 21), finding 155 to have made suicide attempts (SA) and 218 with onset of depression-related suicide ideation (SI). We estimate relative risk (RR), from survival analysis and logistic regression models, to study early use of tobacco, alcohol, cannabis, and inhalants, with covariate adjustments for age, sex, race-ethnicity, and other pertinent covariates. Early-onset of cannabis use and inhalant use for females, but not for males, signaled modestly excess risk of suicide attempt (cannabis-associated RR = 1.9; p = 0.04; inhalant-associated RR = 2.2; p = 0.05). Early-onset of cannabis use by females (but not for males) signaled excess risk for suicide ideation (RR = 2.9; p = 0.006). Early-onset alcohol and tobacco use were not associated with later risk of SA or SI. In light of the relatively modest strength of association, the evidence may well reflect an underlying common diathesis or unmeasured prior confounding influences that link early-onset illegal drug use with later risk of these suicide-related events, rather than an influence of early-onset drug use per se. © 2004 Elsevier Ireland Ltd. All rights reserved. Keywords: Cannabis; Inhalants; Suicide; Suicide attempt; Adolescence; Epidemiology 1. Introduction The main purpose of this epidemiological project was to investigate prospectively the early-onset use of tobacco, alco- hol, cannabis, and inhalants during childhood and early ado- lescence as potential causal influences on subsequent suicide ideation and attempts during a risk period that extends from entry into primary school at age six years through the start of young adulthood. The prospective study originated with a sample of first-graders. The most recent followup assess- ments have been completed some 15–17 years later, as de- scribed by Kellam et al. (1991), Kellam and Anthony (1998), * Corresponding author. Tel.: +1 410 614 2852; fax: +1 410 955 9088. E-mail address: hwilcox@jhsph.edu (H.C. Wilcox). and Storr et al. (2004). As such, the research has some re- semblance to the recent prospective research described by Fergusson et al. (2003); prospective studies tend to have greater resolving power than cross-sectional studies with re- spect to alignment of temporal sequences from earlier drug use and risk of later suicide ideation and attempts. With respect to the potential public health significance of this line of research, we note that the “Call to Action to Prevent Suicide,” our most recent Surgeon General’s report in the United States (US), placed adolescent suicide in the group of the most important public health problems for this country (US Public Health Service, 1999), as it is for the world as a whole (Murray and Lopez, 1996). For example, in 2001, suicide was the third leading cause of death among 15–24 year-olds in the US, accounting for over 12% of deaths in 0376-8716/$ – see front matter © 2004 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.drugalcdep.2004.08.007