Sex Differences in Developmental Trends of Suicide Ideation, Plans, and Attempts among European American Adolescents

Youth suicide constitutes a recognized public health concern (Institute of Medicine [IOM], 2002). Treatment and prevention efforts often target suicidal ideation, plans, and attempts, since these thoughts, feelings, and behaviors predict completed suicide and themselves signify intense suffering. Suicidal crises are also the most common precipitants to psychiatric hospitalization (IOM, 2002). Further, adolescent suicidal episodes predict psychiatric disorders and diminished functioning in the realms of work, education, and social relationships during young adulthood (Fergusson et al., 2005; Reinherz et al., 2006). Suicidal ideation, plans, and attempts among adolescents therefore deserve attention as serious mental health outcomes, and consequently constitute the focus of this study. We investigate the yearly prevalence patterns of suicidal thoughts and behavior by age among European American adolescent boys and girls. European American adolescent girls and boys have higher rates of completed suicide than do Asian and African American adolescents of both sexes (Centers for Disease Control and Prevention [CDC], 2008), so understanding suicide-related phenomena in this population is important. Although numerous studies have assessed specific associations of adolescent suicidality with age and sex (Kessler, Borges & Walters, 1999; Lester, 1991), we know of no studies investigating whether yearly prevalence rates of nonfatal suicide-related outcomes follow different patterns across adolescence, with girls’ and boys’ levels perhaps peaking at different ages. However, such information may well help inform the timing and targeting of preventive interventions, including gatekeeper training (see IOM, 2002). For example, if risk for one of the sexes were to peak only in late adolescence, rather than in early or mid-adolescence, gatekeeper training and health promotion in post-secondary educational institutions (e.g., Holinger, Offer, Barter, & Bell, 1994) may well take on greater urgency for that group, in particular. Developmentally, we have reason to suspect that trends in suicidality may differ between girls and boys: pubertal onset occurs earlier for girls, on average, than for boys, and this biological transition can be a time of risk for girls, in particular (Caspi, Lynam, Moffitt, & Silva, 1993; Ge, Conger, & Elder, 2001). Depression carries one of the highest risks of any psychiatric disorder for suicide ideation, plans, and attempts (Kessler, et al. 1999), and rates of depressive symptomology increase more rapidly for girls in early adolescence than for boys (Ge, Lorenz, Conger, Elder, & Simons, 1994; Ge, Natsuaki, & Conger, 2006). On the other hand, conduct disorder is particularly common among suicidal youth (see IOM, 2002), and it appears that antisocial, delinquent behavior increases earlier for adolescent boys than girls (Marmorstein & Iacono, 2005. Based on the weight of risk factors in early adolescence, however, it may be that adolescent girls’ suicidality rates reach their maximum at an earlier age than do boys’ rates. Inspection of rates of completed adolescent suicide by age and sex in the United States from 1999–2004 reveals that rates increased dramatically from year to year for girls during early adolescence, but then stabilized by about age 16, whereas the rates for boys continued to increase yearly through age 19 (CDC, 2008). It remains unknown whether prevalence patterns of suicide ideation, plans, and attempts by sex follow a similar pattern, however. Two studies have focused on related questions: Lewinsohn and colleagues (2001) investigated the timing of first onset of suicide attempts in a normative sample and found that risk of onset for both boys and girls peaked during mid adolescence. However, young women’s risk precipitously dropped after age 18, whereas young men’s risk only slightly decreased in late adolescence. A cross-sectional population-based study of a depressed sample (Wunderlich, Bronisch, Wittchen, & Carter, 2001) found a greater proportion of attempts (but not ideation) for 14–17 year-old girls relative to boys, and no sex differences in attempts or ideation in late adolescence, suggesting a similar late-adolescent increase or maintenance in attempt risk among males (or, decline in such risk for females). Somewhat in contrast to Wunderlich et al.’s (2001) findings on ideation, a recent study (Rueter, Holm, McGeorge, & Conger, 2008) reports descriptive statistics which suggest that proportions of ideation among males may increase between ages 14 and 17, but decrease for females. Systematic investigation by sex of trajectories of ideation, plans, and attempts from early to late adolescents in a normative population is therefore warranted to gain an accurate picture of developmental patterns of suicidal episodes in this life phase. Given that many individuals report more than one episode of suicidal thoughts or attempts (Kessler et al., 1999; Lewinsohn, Rohde & Seeley, 1994), we believe examining patterns of such occurrences beyond just first onset plays an important role in understanding adolescent boys’ and girls’ risk for suicidal episodes across adolescence. Every indication from the literature supports the contention that those who experience a suicidal episode more than once carry a higher burden of psychopathology and are at greater risk of future attempts and of completed suicide (for a review, see IOM, 2002). Most studies, due to the sparse data generally available related to suicide-related phenomena, use binary outcome variables (no suicidality vs. some suicidality), which also may obscure important information about the extent of the problem. Investigation of prevalence patterns for suicidal ideation, plans, and attempts irrespective of first onset, and which includes information about whether suicidal episodes were experienced just once, or more than once within the reporting period, may provide important information about normative developmental trends in these serious problems.