Health Impacts of Citywide and Localized Power Outages in New York City

BACKGROUND: Previous studies investigated potential health effects of large-scale power outages, including the massive power failure that affected the northeastern United States and Ontario, Canada, in August 2003, and outages associated with major storms. However, information on localized outages is limited. OBJECTIVE: The study sought to examine potential health impacts of citywide and localized outages in New Yolk City (NYC). METHODS: Along with the citywide 2003 outage, localized outages in July 1999 and July 2006 were identified. We additionally investigated localized, warm- and cold-weather outages that occurred in any of 66 NYC electric-grid networks during 2002-2014 using New York State Public Service Commission data. Mortality and hospitalizations were geocoded and linked to the networks. Associations were estimated using Poisson time-series regression, including examining distributed lags and adjusting for temperature and temporal trends. Network-specific estimates were pooled by season. RESULTS: Respiratory disease hospitalizations were associated with the 2006 localized outage [cumulative relative risk [CAR] over 0-1 lag day, lag(01) = 2.26 (95% confidence interval [CI]: 1.08, 4.74)] and the 2003 citywide outage, but not with other localized, warm-weather outages. Renal disease hospitalizations were associated with the 2003 citywide outage, and with localized, warm-weather outages, pooled across networks [RR at lag(3) = 1.16 (95% CI: 1.00, 1.34)], but not the 2006 localized outage. All-cause mortality was positively associated with the 1999, 2003, and 2006 outages (significant for the 2003 outage only), but not with other localized, warm-weather outages. Localized, cold-weather outages were associated with all-cause mortality [lag(01) CRR = 1.06 (95% CI: 1.01, 1.12)] and cardiovascular disease hospitalizations [lag, CRR = 1.14 (95% CI: 1.03, 1.26)], and fewer respiratory disease hospitalizations [lag(03) CRR = 0.77 (95% CI: 0.61, 0.97)]. CONCLUSIONS: Localized outages may affect health. This information can inform preparedness efforts and underscores the public health importance of ensuring electric grid resiliency to climate change.