Perception of Pulmonary Function and Asthma Control: The Differential Role of Child Versus Caregiver Anxiety and Depression

Asthma and anxiety share strikingly similar symptoms, such as dyspnea, dizziness, chest tightness, choking, and sensations of smothering. The overlap in symptoms may lead individuals to mistake anxiety as an asthma attack, which has been shown in adults to result in excessive use of quick-relief medications for asthma and worse health-related quality of life (Feldman, Lehrer, Borson, Hallstrand, & Siddique, 2005). Anxiety and depressive disorders in children are associated with greater subjective reports of asthma symptoms, independent of disease severity (Richardson et al., 2006). The combination of negative emotions and ambiguous physical symptoms may lead children to over-perceive asthma symptoms (Rietveld & Prims, 1998). Few studies have examined subjective estimates and objective measures of lung function in children concurrently, which is an essential component in the measurement of symptom perception due to the variable nature of asthma. For example, children may report experiencing asthma symptoms during the past couple of weeks to providers, but have normal pulmonary function at a clinic visit. The missing data in this situation would be whether or not the child experienced impaired pulmonary function at home during this time period. The evidence showing a relationship between children’s anxiety, depression, and perception of pulmonary function has varied based on the methodology used. One laboratory-based study administered methacholine, a drug used to induce bronchoconstriction, and showed that trait anxiety in children with asthma was associated with over-perception of respiratory compromise when pulmonary function was normal or mildly compromised (Chen, Hermann, Rodgers, Oliver-Welker, & Strunk, 2006). This relationship between anxiety and over-perception was not present at more severe levels of bronchoconstriction. Two studies conducted in the child’s home have shown no relationship between children’s anxiety and depressive symptoms and perception of pulmonary function with naturally occurring asthma (Fritz, McQuaid, Spirito, & Klein, 1996; Koinis-Mitchell et al., 2009). The methodology in these studies involved children predicting their peak expiratory flow (PEF) and receiving feedback by being able to see their actual PEF. Recent evidence, though, shows that children who predict PEF and then receive feedback have greater perceptual accuracy of pulmonary function and higher rates of adherence to controller medications for asthma compared with children who predict PEF but are blinded to their actual PEF values (Feldman et al., 2012). PEF prediction with feedback may have functioned as an intervention in these previous studies, thereby masking the relationship between children’s anxiety and depressive symptoms and over-perception of respiratory compromise. Therefore, studies conducted in naturalistic settings without PEF feedback are needed. Furthermore, it is not clear whether children’s anxiety or depressive symptoms are stronger predictors of perception of pulmonary function. Caregiver depressive and anxiety symptoms are risk factors for higher levels of asthma morbidity in children, although most prior studies have not included measures of children’s pulmonary function. Caregiver depressive symptoms are associated with more frequent asthma-related urgent care visits (Brown et al., 2006), emergency department use (Bartlett et al., 2001), and hospitalizations (Weil et al., 1999) in children. Children of caregivers with an anxiety disorder are also at greater risk for asthma-related hospitalizations versus children of caregivers without anxiety (Brown et al., 2006). The relationship between maternal depressive symptoms and children’s asthma morbidity might be linked to lower maternal self-efficacy to manage attacks and lower asthma medication adherence (Bartlett et al., 2004). A limitation of the majority of prior studies is the use of caregiver self-report measures of depressive symptoms, as opposed to clinical interviews to determine psychiatric disorders. Furthermore, it is not clear whether caregiver depressive and anxiety disorders have an effect on children’s actual pulmonary function and/or children’s perception of pulmonary function. The purpose of the present study was to examine which subjective versus objective components of asthma control are associated with child versus caregiver anxiety and depression. We hypothesized that children’s anxiety and depressive symptoms would be associated with greater subjective impairment (i.e., over-perception of respiratory compromise, greater quick-relief medication use), whereas caregivers’ anxiety and depressive disorders would be associated with greater objective impairment (i.e., worse pulmonary function).