Heat-related Deaths in New York City, 2013
Extreme heat events kill more people, on average, than any other type
of extreme weather event in both New York City (NYC) and the United
States overall.¹ Vulnerable individuals, such as older adults and those
with underlying chronic physical health conditions or with serious
mental or cognitive disorders, have the highest risk of dying from an
extreme heat event.
Deaths from extreme heat are defined as those resulting from a high
body temperature or in which heat exposure is recognized as a
contributing cause (“heat-related deaths”) on death certificates. This
definition does not include deaths from natural causes above the
number expected for the time of year (“excess mortality”), which are
estimated statistically (see box on page three). From 2000 to 2012, 162
heat-related deaths occurred in New York City, including 70 (43%) that
were reported during two extreme heat events in 2006 and 2011.
This report describes characteristics and circumstances of heat-related deaths in New York City during the 2013
summer season based on a review of death certificates and medical examiner investigation reports. An extreme
heat event that occurred July 14 to 20, 2013, was among the three most severe in New York City since 2000,
with heat indices reaching at least 95°F for seven consecutive days and peaking at 109°F.
Most heat-related deaths in 2013 were associated with a single extreme heat event
• Nineteen of the 26 (73%) heat-related deaths identified by DOHMH surveillance during the 2013 warm season
were associated with the July 14 to 20 extreme heat event.
• The maximum temperature (99°F) and maximum heat index (109°F) were recorded on July 19, 2013. For 12 of
the heat-related deaths, the date of illness onset was July 19 or 20; two additional deaths on July 20 did not
have a recorded date of illness onset.
• Three heat-related deaths were associated with a July 4 to 7 extreme heat event.
• Three heat-related deaths were associated with illegal methylamphetamine (MDMA) use at two outdoor
concerts; two deaths in late August and one during the July 14 to 20 extreme heat event.
New York City Department of Health and Mental Hygiene August 2014, No. 47
Epi Data Brief
Extreme Heat Event
The National Weather Service (NWS)
issues heat advisories. In New York City
advisories are issued when the forecast
calls for two or more consecutive days
when the heat index, which
incorporates both air temperature and
relative humidity, will reach at least
95°F (35°C) or at least one day when
the heat index reaches 100°F (37.8°C).
For this report, extreme heat event
dates were defined as dates meeting
these conditions based on the highest
observed hourly weather among
LaGuardia Airport, JFK Airport, or
Central Park NWS monitoring stations.
2013 New York City heat-related deaths and maximum temperature or heat index
Date of illness onset was missing for two deaths, represented here based on date of death (July 20, 2014).
Sources: Preliminary NYC DOHMH Vital Records 2013 as of June 2014, National Weather Service
0
2
4
6
8
10
60
70
80
90
100
110
25 27 29 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Jun 2013 Jul 2013 Aug 2013
# of heat-related deaths
Maxmum temperatuve
or heat index (°F)
Date of onset
Number of heat-related deaths
Max daily temp or heat index
95°F (extreme heat event threshold)
Epi Data Brief, No. 47 Page 2
Nearly all heat-related deaths occurred among adults with at least one pre-existing
health risk factor
There were 24 heat-related deaths among adults ages 18 and older, and two deaths among children in summer
2013. Among the adult heat-related deaths:
• More than half (58%) had a
cardiovascular condition.
• More than one third (38%) were
reported to have evidence of
alcohol or drug abuse at the time of
illness onset or had a history of
chronic substance abuse.
• More than one quarter (29%) had a
history of diabetes.
• One fifth (21%) had a serious
mental health or cognitive disorder
(e.g., developmental disabilities,
schizophrenia).
• The proportion of decedents who were obese (Body
Mass Index (BMI) ≥ 30, 24%) was similar to the
prevalence among all NYC adults.
• The heat-related death rate was greater among
older adults than among those younger than 65
years (7.7 vs. 2.3 per million population).
• Nearly one third of adult heat-related deaths in
2013 (33%) were among those ages 65 or older.
• Of the deaths among adults ages 18 to 64 years, 15
in 16 (94%) had at least one health risk factor.
The majority had onset of illness at home
• Nearly two thirds (65% or 17 deaths) of all
heat-related deaths in 2013 had an onset of
illness in the decedent’s home.
• Among those exposed at home for whom
information about home air conditioning was
available (nine), eight did not have a working
air conditioner or the air conditioner was not
running when the death scene was
investigated.
• At least six of the decedents exposed at home
were using fans at the time of death.
• Of those who died or were exposed at home,
ten (59%) did not live alone.
Source: 2013 NYC DOHMH Vital Records data and OCME case investigation records
ages 18 and older in New York City (n=24) by selected risk
Characteristic n %
Ages 65 years and older
8
33%
Specific conditions
Cardiovascular disease
14
58%
Obese (BMI = 30 or higher)
6
25%
Diabetes
7
29%
Drug or alcohol abuse
9
38%
Cognitive or mental health condition
5
21%
Respiratory conditions
1
4%
Residence
65%
Workplace
8%
Outside
27%
Percent of heat-related deaths by place of
exposure, New York City, 2013
Source: 2013 OCME case investigation records
Authors: Sarah Walters, Kathryn Lane, Eryn Murphy
Acknowledgements: Thomas Matte, Carolyn Olson, Kacie Seil
________________________________________________
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New York City Department of Health and Mental Hygiene August 2014
Epi Data Brief, No. 47 Page 3
New York City Department of Health and Mental Hygiene August 2014
The risk of deaths from natural causes can increase during extreme heat events
Deaths from extreme heat also include “excess deaths,” which can result from exacerbation of chronic health
conditions by hot weather. Excess deaths are estimated as the number of deaths due to natural causes above
the number expected for the time of year. Statistical models are used to compare average death rates
associated with extreme heat events to the expected death rates based on usual seasonal trends. For the
years 1997 to 2013, the Health Department estimated an annual average of 94 excess deaths from natural
causes associated with extreme heat events, including the three days following each heat event to allow for
delayed effects of heat. Annual estimates of excess heat-related deaths vary with the weather and are not
precise because of random variation in daily death rates. For 2013, a preliminary Health Department
estimate of 140 excess deaths from extreme heat events was not statistically different from the 1997-2013
average. Unlike the heat-related deaths described in this report, which can be individually identified and
investigated, the individual circumstances of death cannot be investigated for excess natural cause deaths.
However, estimating excess deaths more accurately demonstrates the true burden of heat mortality. For
example, in 2013 the 22 heat-related deaths associated with extreme heat events accounted for just 14% of
the total mortality burden of extreme heat. Source: Abstract: Matte T, Lane K, Ito K. Excess non-external
cause deaths attributable to heat waves in New York City, 1997-2013. International Society for
Environmental Epidemiology Annual Conference, 2014. Accepted.
Data sources
NYC DOHMH Vital Records: NYC Annual Summary of Vital Statistics, 2000-2012. Heat-related deaths were identified through a
review of death certificates to identify those with assigned International Classification of Diseases, 10
th
Revisions (ICD-10) codes X30
“exposure to excessive natural heat” or T67 “heatstroke and sunstroke” as primary or secondary causes of death from May –
September. Records with a man-made cause of heat exposure (W92) were excluded. For 2000-2012, final vital records were
reviewed; for 2013, preliminary data as of June 2014 were reviewed and counts represent preliminary estimates.
Office of Chief Medical Examiner (OCME) Case Investigation Records: Electronic records for all heat stroke deaths were reviewed to
obtain information about the characteristics and circumstances of heat-related deaths, including medical conditions, body mass
index (BMI – based on post-mortem height and weight measurements), and information about air conditioning for those exposed at
home. Chronic health conditions noted in either the death certificate or OCME records were captured, as well.
Community Health Survey (CHS): Data on BMI prevalence among all NYC adults were obtained from NYC Dept. of Health and Mental
Hygiene. EpiQuery: NYC Interactive Health Data System – CHS 2012. Viewed 6/25/14. nyc.gov/health/epiquery
DOHMH Population Estimates: Rates were calculated using NYC Dept. of Health and Mental Hygiene population estimates, modified
from U.S. Census Bureau intercensal population estimates from 2000-2012 and last updated July 22, 2013.
Reference
1
Office of Climate, Water, and Weather Services. Weather fatalities, 2013. Silver Spring, MD: US Dept of Commerce, National
Weather Service; 2014. Available at nws.noaa.gov/om/hazstats.shtml
Data Sources
NYC DOHMH Vital Records: NYC Annual Summary of Vital Statistics, 2000-2012. Heat-related deaths were
identified through a review of death certificates to identify those with assigned International Classification of
Diseases, 10th Revisions (ICD-10) codes X30 “exposure to excessive natural heat” or T67 “heatstroke and sunstroke”
as primary or secondary causes of death from May – September 2013 as of June 2014. Records with a man-made
cause of heat exposure (W92) were excluded.
Office of Chief Medical Examiner (OCME) Case Investigation Records: Electronic records for all heat stroke
deaths were reviewed to obtain information about the characteristics and circumstances of heat-related deaths,
including medical conditions, body mass index (BMI – based on post-mortem height and weight measurements), and
information about air conditioning for those exposed at home. Chronic health conditions noted in either the death
certificate or OCME records were captured, as well.
DOHMH Population Estimates: Rates were calculated using NYC Dept. of Health and Mental Hygiene population
estimates, modified from U.S. Census Bureau intercensal population estimates from 2000-2012 and last updated July
22, 2013.
Table 2.
Percent of New York City heat-related deaths with underlying chronic health conditions, 2013
Table 3.
Percent and rate of New York City heat-related deaths by demographic characteristics, 2000-2012
and 2013
Epi Data Tables
Table 1.
Percent of New York City heat-related deaths by characteristic, 2013
New York City Department of Health and Mental Hygiene
August 2014, No. 47
Heat-related Deaths in New York City, 2013
Data Tables
Epi Data Tables, No. 47 New York City Department of Health and Mental Hygiene
Pages 2
Characteristic N
Percent
Socio-demographics
Age
0-14
2 8
15-34
4 15
35-64
12 46
65+
8 31
Sex
Female 9 35
Male 17 65
Race/Ethnicity
Non-Hispanic white 9 35
Non-Hipanic Black 9 35
Hispanic 5 19
Non-Hispanic Asian 2 8
Other/Missing 1 4
Borough of Residence
Bronx 2 8
Brooklyn 9 35
Manhattan 4 15
Queens 4 15
Staten Island 3 12
Unknown 4 15
Place of Illness Onset
Inside Not At Own Residence 2 8
Outside 7 27
Residence 17 65
Days Between Onset and Death
0 16 62
1 7 27
23 1 4
Unknown 2 8
Place of Death
In Emergency Department/
Outpatient Facility
9 35
In Hospital 6 23
Residence 9 35
Unknown 1 4
Fan
Present and On 6 35
Present, Not On 1 6
Not Present/Unknown 10 59
Air Conditioner
Not Present 7 41
Present and On 1 6
Present, Not On 1 6
Unknown 8 47
Table 1. Percent of New York City heat-related deaths by characteristic, 2013
Source: NYC Office of Vital Statistics Data, 2013
Selected Housing Characteristics for those with illness onset in residence (n=17)
Epi Data Tables, No. 47 New York City Department of Health and Mental Hygiene
Page 3
Characteristic N Percent
Age
26 100
< 65 years 18 69
65 years and older 8 31
Any chronic condition*
Cardiovascular 14 58
Obese (BMI = 30 or higher) 6 25
Diabetes 7 29
Substance use, including alcohol (history
or at time of illness onset)
9 38
Cognitive or mental health conditions
5 21
Respiratory conditions 1 4
*Among adults ages 18+ (n=24)
Table 2. Percent of New York City heat-related deaths with underlying chronic health conditions, 2013
Source: NYC Office of Vital Statistics Data, 2013; OCME medical review
Epi Data Tables, No. 47 New York City Department of Health and Mental Hygiene
Page 4
N Percent
Average annual rate
per million*
N Percent
Average annual rate
per million*
Female age group (years)
0-14
1 0.6 0.1 1 3.8 1.4
15-34
5 3.1 0.3 1 3.8 0.8
35-64
22 13.6 1.0 4 15.4 2.4
65+
40 24.7 5.2 3 11.5 4.8
Male age group (years)
0-14
3 1.9 0.3 1 3.8 1.3
15-34
9 5.6 0.6 3 11.5 2.4
35-64
56 34.6 2.9 8 30.8 5.3
65+
26 16.0 5.2 5 19.2 11.9
Neighborhood Poverty Level**
Low (<10%)
27 16.7 1.2 2 7.7 1.2
Medium (10 to <20%)
53 32.7 1.4 11 42.3 3.7
High (20 to <30%)
38 23.5 1.5 4 15.4 2.0
Very High (30%+)
37 22.8 1.8 4 15.4 2.6
Unknown
7 4.3 N/A 5 19.2 N/A
Race/Ethnicity
Non-Hispanic white
59 36.4 1.6 9 34.6 2.9
Non-Hispanic Black
80 49.4 3.2 9 34.6 4.7
Hispanic
16 9.9 0.5 5 19.2 2.1
Non-Hispanic Asian
4 2.5 0.3 2 7.7 1.8
Other/Missing
3 1.9 N/A 1 3.8 N/A
†Includes deaths occuring between May and September defined as those with International Classification of Diseases, 10th Revisions (ICD-10) codes X30 “exposure to excessive
natural heat” or T67 “heatstroke and sunstroke” listed as primary or secondary causes of death among NYC residents are those with unknown residence who died in NYC.
Records with a man-made cause of heat exposure (W92) were excluded. The 2013 deaths include three non-NYC residents who died in NYC.
Table 3. Percent and rate of New York City heat-related deaths by demographic characteristics, 2000-2012 and 2013
Source: NYC Office of Vital Statistics Data, 2000-2013; NYC DOHMH Population Estimates 2000-2012
*2000-2012 average annual rates calculated using 2000-2012 population estimates produced by the NYC DOHMH; 2013 rates based on 2012 population estimates. Rates are
not age-adjusted.
**Neighborhood poverty is based on ZIP code and is defined as the percent of residents in each ZIP code area with incomes below 100% of the Federal Poverty Level per
American Community Survey 2007-2011. Rates based on 2010 census data.
2000-2012 (N=162)†
2013 (N=26)
Characteristic