Novel Surveillance of Psychological Distress during the Great Recession

Economic stressors have been retrospectively associated with net population increases in psychological distress (PD). However, no sentinels exist to evaluate contemporaneous associations. Aggregate Internet search query surveillance was used to monitor population changes in PD around the United States' Great Recession. Monthly PD query trends were compared with unemployment, underemployment, homes in delinquency and foreclosure, median home value or sale prices, and S&P 500 trends for 2004-2010. Economic indicators were used to predict PD one to seven months into the future. PD queries surpassed 1,000,000 per month, of which 300,000 may be attributable to the Great Recession. A one-percentage point increase in mortgage delinquencies and foreclosures was associated with a 16% (95%CI,9-24) increase in PD queries one-month, and 11% (95%CI,3-18) four months later, in reference to a pre-Great Recession mean. Unemployment and underemployment had similar associations half and one-quarter the intensity. "Anxiety disorder,” "what is depression,” "signs of depression," "depression symptoms,” and "symptoms of depression" were the queries exhibiting the strongest associations with mortgage delinquencies and foreclosures, unemployment or underemployment. Housing prices and S&P 500 trends were not associated with PD queries. Because the economy is constantly changing, this work not only provides a snapshot of recent associations between the economy and PD but also a framework and toolkit for real-time surveillance going forward. Health resources may be swiftly allocated and clinicians may alter screening practices conditional on changes in PD query trends. Public policy leaders may use PD query trends to estimate the health impacts associated with economic stimuli.