Hurricane Sandy made landfall on October 29, 2012, causing a coastal storm surge and extensive flooding, which led to the closure of several health care facilities in New York City (NYC) and prolonged interruptions in service delivery. The impact on mental health–related emergency department (ED) and inpatient hospital service utilization was studied.

Data came from the New York Statewide Planning and Research Cooperative System. We obtained mental health–related data among NYC residents from 2010 to 2013. Patients were grouped into 5 geographic areas, including service areas of closed hospitals, the Hurricane Sandy evaluation zone, and all of NYC. The Farrington method was used to detect increases in ED visits and hospitalizations for the post-Sandy period.

Open hospitals experienced a substantial increase in psychiatric ED visits from patients living in the service areas of closed hospitals. This surge in psychiatric ED visits persisted for 4 to 6 months after Hurricane Sandy. However, the increase in psychiatric hospitalizations was observed for 1 to 3 months.

Several NYC hospitals received a substantially larger number of ED patients from service areas of closed hospitals after Hurricane Sandy, unlike other hospitals that experienced a decrease. Because of potential surges in the number of psychiatric ED visits, resource allocation to hospitals should be considered. (Disaster Med Public Health Preparedness. 2016;10:512–517)

Closure of several New York City (NYC) hospitals after Hurricane Sandy caused an unanticipated, extended surge in patient demand at open hospitals. This study identified hospitals with a significant increase in mental-health-related emergency department, inpatient, and outpatient visits from Medicaid patients displaced by Hurricane Sandy.

NYC Medicaid patients were classified into non-mutually-exclusive geographic categories corresponding to residence in areas served by Bellevue Hospital Center and Coney Island Hospital, the hurricane impact area, and all of NYC. For each geographic region, we compared the observed to the expected number of service visits in the 6 months after the storm. The expected number of visits was calculated from 2-year trends in mental health claims.

Twenty-four facilities in all 5 NYC boroughs experienced patient redistribution from storm-affected areas. Eighteen facilities had a concurrent surge in total Medicaid patients, which suggested that redistribution had a greater impact on resource use at these locations.

The redistribution of Medicaid patients after Hurricane Sandy increased mental health service utilization at facilities not near flooded areas. Our findings can aid in surge capacity planning and thereby improve the continuity of mental health care after a natural disaster. (Disaster Med Public Health Preparedness. 2016;10:420–427)