Prevalence and correlates of generalized anxiety disorder among older adults in the Australian National Survey of Mental Health and Well-Being

Abstract

Generalized anxiety disorder (GAD) occurs commonly, with widespread consequences including decreased functioning and wellbeing, and increased consumption of health resources. Notwithstanding its prevalence and impact, knowledge about GAD in older adults is still scarce. Accordingly, the main goals of this study were to estimate the prevalence and analyze the correlates of 12-month DSM-IV GAD in older community-residing adults. The sample was drawn from the 2007 Australian National Survey of Mental Health and Well-Being and consisted of 3035 participants aged between 55 and 85years, assessed by lay interviewers with the fully-structured Composite International Diagnostic Interview. Eighty-four participants were diagnosed with GAD, equivalent to a weighted 12-month population prevalence of 2.8% (95% CI: 2.0, 3.7). In a multivariate logistic regression model older age (OR=0.24, p=0.006), functional limitations (OR=1.07, p=0.001), lifetime depression comorbidity (OR=5.31, p<0.001), concerns about having a serious illness despite doctor's reassurance (OR=2.29, p=0.021), and family history of anxiety or depression (OR=2.41, p=0.007) were the most significant predictors of 12-month GAD in older adults. This was a cross sectional study, limiting causal inferences. In community-residing older adults GAD is highly prevalent and strongly associated with functional limitations, psychiatric comorbidity and increased medication intake. These findings suggest the need for greater clinical awareness of GAD among older adults.