Anxiety and related outcomes in young adults 7 to 19 years after receiving treatment for child anxiety.

Anxiety disorders are common in youth (e.g., Bernstein & Borchardt, 1991) and adults, based on 12-month prevalence estimates from the general population (Kessler, Chui, Demler, & Walters, 2005) and across the lifespan (28.8%; Kessler, Berglund, Demler, Jin, & Walters, 2005). Approximately 10 to 20% of children in the general population and primary care settings report distressing levels of anxiety (Chavira, Stein, Bailey, & Stein, 2004; Costello, Mustillo, Keeler, & Angold, 2004). Research suggests that most anxiety disorders do not abate over time (e.g., Pine, Cohen, Gurley, Brook, & Ma, 1998). Indeed, retrospective reports demonstrate that adults with anxiety disorders report having experienced disturbing anxiety as children (e.g., Ost, 1987; Sheehan, Sheehan, & Minichiello, 1981) and older youth report higher levels of anxiety and depression compared to younger children, suggesting untreated anxiety symptoms worsen over time. Anxiety disorders in youth have important long-term implications in terms of their association with later depressive disorders (Alpert, Maddocks, Rosenbaum, & Fava, 1994; Angold, Costello, & Erkanli, 1999; Biederman, Faraone, Mick, & Lelon, 1995; Strauss, Lease, Last, & Francis, 1988), suicidal attempts and ideation (Brent et al., 1986; Rudd, Joiner, & Rumzek, 2004), and substance use (Costello, Mustillo, Erkanli, Keeler, & Angold, 2003; Lopez, Turner, & Saavadra, 2005). As age increases, the presence of an anxiety disorder has an associated increase in the likelihood of a depressive disorder (Beesdo et al., 2007, Pine et al., 1998), and anxiety disorders typically precede the onset of substance use disorders (SUDs; Merikangas et al., 1998). Given the high lifetime co-occurrence of anxiety and SUDs (35% to 45%; Kessler et al., 1996) and the deleterious outcomes associated with substance dependence (Toumbourou et al., 2007), this primacy warrants further investigation. Indeed, there is evidence that effective short-term treatment for adolescent depression is associated with reduced SUDs (Curry et al., 2012). Initial data suggested that CBT for child anxiety may allay later substance use (e.g., Kendall, Safford, Flannery-Schroeder, & Webb, 2004), but that evaluation was undertaken before participants reached the age of greatest risk for associated disorders. Several studies have examined CBT for childhood anxiety and literature reviews support its utility: CBT can be considered an efficacious treatment (based on the criteria proposed by Chambless & Hollon, 1998; see Hollon & Beck, 2013; Kazdin & Weisz, 1998; Ollendick & King, 2012; Silverman, Pina, & Viswesvaran, 2008). Several randomized clinical trials (RCTs) reported the efficacy of one version of CBT for anxious youth, the Coping Cat program (Kendall & Hedtke, 2006), when compared to alternate psychological treatments (e.g., Kendall, Hudson, Gosch, Flannery-Schroeder, & Suveg, 2008) and to medications and pill placebo (e.g., Walkup et al., 2008). Although multiple research groups have advanced the treatment of anxiety disorders in children (see also Barrett, Dadds, & Rapee, 1996; Beidel et al., 2007; Silverman et al., 2008), limited evidence exists with respect to sequelae at the time in adulthood when such disorders are likely to emerge. Several one-year follow-ups have been conducted (e.g., Kendall et al., 1997; Kolko, Loar, & Sturnick, 1990), as well as a 3-year (Beidel, Turner, Young, & Paulson, 2005), 5-year (Beidel, Turner, & Young, 2006), 6-year (Barrett, Duffy, Dadds, & Rapee, 2001) and 7.4-year follow-ups (Kendall et al., 2004). Longer follow-ups are uncommon and those that are available lack appropriate methodological rigor (e.g., do not follow a RCT). A review by Nevo and Manassis (2009) highlighted the dearth of long-term outcome studies of anxious youth and the lack of evidence for the role early anxiety treatment might play in healthy development into adulthood (see also Hirshfeld-Becker, Micco, Simoes, & Henin, 2008). The present study evaluated outcomes associated with treatment for childhood anxiety by comparing (a) successfully treated and (b) unsuccessfully treated participants a mean of 16.24 years after the completion of treatment. The primary aim examined whether participants treated successfully during childhood differ from those for whom treatment was less successful on diagnoses of (a) adult anxiety, (b) depression, and (c) SUDs in young adulthood. A second aim examined whether the two treatment outcome groups differed from the general population on diagnoses of anxiety, depression, and SUDs in early adulthood. It was hypothesized that effective treatment for an anxiety disorder in childhood would reduce the occurrences of anxiety and related disorders in young adulthood. Further, it was hypothesized that successfully treated participants would be no more likely to meet criteria for an anxiety, mood, or SUD diagnosis than individuals in the community, whereas unsuccessfully treated participants would be more likely to meet criteria for a diagnosis than community individuals.