Heritability of Childhood Anxiety

The presence of behavioral inhibition is assessed by behavioral observations of the child and sometimes by parent report. By school age, however, child-report and teacher-report inventories can also contribute to the assessment. Two common standardized measures (Achenbach, 1991; March, 1998) are listed in the Table. Some children, however, do not freely acknowledge anxiety (Manassis et al., 1997), so parental reports of avoidant, inhibited behavior should be taken seriously.

With the onset of adolescence, children with persistent behavioral inhibition can experience more intense social phobia (Schwartz et al., 1999). Previously untreated anxieties of middle childhood may also become problematic as expectations of independent functioning increase at adolescence. For example, the inhibited child who has always feared speaking to peers on the telephone can avoid this situation by asking parents to help. At adolescence, this reliance on parents may no longer be considered socially acceptable.

The failure to treat earlier anxieties may also erode self-esteem. There is an increased incidence of depression in anxious children at adolescence, especially in those severely impaired by their anxieties. This has led some authors to suggest a progression to depression in more impaired children (Brady and Kendall, 1992). Preventing this outcome through early treatment of anxiety could thus ameliorate the long-term morbidity associated with comorbid anxiety and depression. Furthermore, there is an unfortunate association between alcohol(Drug information on alcohol) abuse and social phobia in adolescence (Ginsburg et al., 1998; La Greca and Lopez, 1998). Such teens are thought to self-medicate their social anxiety, not having learned more adaptive coping strategies.

Anxiety disorders are increasingly thought to be polygenic, suggesting that additional constitutional risk factors exist besides behavioral inhibition. Numerous biochemical and neuroimaging studies are examining correlates of specific anxiety disorders (Pine and Grun, 1999). Few of these disorder-specific findings are yet being applied clinically; one exception is the Anxiety Sensitivity Index and the corresponding child instrument (Silverman et al., 1999). Anxiety sensitivity is a predisposition to react to autonomic arousal with anxiety and has been specifically linked to panic disorder. People with this sensitivity tend to attribute physical signs of arousal as representing a serious illness (e.g., palpitations signaling imminent cardiac arrest) rather than a more benign cause (palpitations due to consuming a strong cup of coffee). Questionnaire measures of this tendency can be helpful in assessing vulnerability to panic disorder and in beginning cognitive interventions for panic that focus on realistic reappraisal of physical sensations.

This brief review of heritable factors relevant to assessing and treating anxiety in children has focused on interventions that are informed by an appreciation of inhibited temperament and anxiety sensitivity. It is hoped that early amelioration of these risk factors will reduce the negative sequelae of untreated childhood anxiety disorders.