BACKGROUND: Previous studies focused on the health effects of large-scale power outages, such as the August 2003 Northeast outage or those associated with major storms. However, understanding of the health impacts of localized outages is limited. The aim of this study was to examine the health impacts on multiple outcomes of citywide and localized outages in New York City (NYC).
METHODS: In addition to the citywide 2003 outage, localized outages in July 1999 and July 2006 were identified. We additionally investigated localized, warm- and cold-season outages that occurred in any of 66 NYC electric grid networks during 2002-2014 using data from the New York State Public Service Commission. Mortality, hospitalizations and emergency department visits were geo-coded and linked to the networks. Cumulative relative risks and 95% confidence intervals (CRR [95% CI]) were estimated using Poisson time-series analysis with a distributed lag model, adjusting for temperature and temporal trends. Network-specific estimates were pooled by season.
RESULTS: The 2006 power outage was positively associated with respiratory hospitalizations (2.26 [1.08, 4.74]). Warm-weather outages were associated with renal hospitalizations (1.16 [1.00, 1.34]). Both associations were also observed with the 2003 outage. Hospitalization data was not available for the 1999 outage. The magnitude of risks for all-cause mortality with the localized 2006 and 1999 outages were comparable, if not greater, to the citywide 2003 outage, though not statistically significant. Cold-weather outages were associated with mortality (1.06 [1.01, 1.12]) and cardiovascular disease hospitalizations (1.14 [1.03, 1.26]).
CONCLUSIONS: Our results suggest that localized power outages may impact health.