Heat-Associated Deaths in Maricopa County, AZ
Final Report for 2021

Photograph by Dan Sorensen:
http://www.dansorensenphotography.com/

Heat Death Report | 2021

Contents
ACKNOWLEDGEMENTS .......................................................................................................... 2
INTRODUCTION ..................................................................................................................... 3
RESULTS ................................................................................................................................ 4
Heat-Associated Deaths by Year ............................................................................................ 4
Heat-Associated Deaths by Month ......................................................................................... 5
Heat-Associated Deaths and Temperatures ........................................................................... 6
Demographic Characteristic of Heat-Associated Deaths ......................................................... 7
Heat-Associated Deaths by Residency .................................................................................... 7
Death Rates Among Maricopa County Residents .................................................................... 8
Heat-Associated Deaths by Place of Injury ........................................................................... 10
Outdoor Deaths ......................................................................................................................... 14
Indoor Deaths ............................................................................................................................ 17
Air Conditioning Use for Indoor Injuries ............................................................................... 19
Substance Use among Heat-Associated Deaths .................................................................... 20
Living Situation among Heat-Associated Deaths ................................................................... 23
Education and Heat-Associated Deaths ................................................................................ 24
CONCLUSIONS ..................................................................................................................... 25
Appendix 1 - Background and Methodology......................................................................... 26
Appendix 2 – Tables ............................................................................................................ 30

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Heat Death Report | 2021

Acknowledgements
The Maricopa County Department of Public Health (MCDPH), Office of Epidemiology
would like to thank the following agencies for their contributions to this report:
➢ Maricopa County Office of the Medical Examiner (OME)
➢ Maricopa County Office of Vital Registration (OVR)
➢ Arizona Department of Health Services (ADHS), Office of Vital Registration
➢ National Weather Service (NWS)
➢ Maricopa Association of Governments (MAG)
➢ Local hospitals (infection preventionists, emergency departments, social worker
staff)
➢ City of Phoenix Heat Relief Network

To receive additional data, please submit a data request form through the
Maricopa County Public Health website here. A staff member from the
Climate and Health team will contact you to discuss your request.
You may also contact the Climate and Health Team through email:

Tianna Baker: Tianna.baker@maricopa.gov
Aaron Gettel: Aaron.gettel@maricopa.gov
Jackie Ward: Jackie. ward@maricopa.gov
Vjollca Berisha

Primary Author: Tianna Baker, Climate and Health Epidemiology Data Analyst

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Heat Death Report | 2021

Introduction
Mortality from environmental heat is a significant public health problem in
Maricopa County, especially because it is largely preventable. Maricopa County
has conducted heat surveillance since 2006. Each year, the enhanced heat
surveillance season usually begins in May and ends in October. The main goals of
heat surveillance are to identify the demographic characteristics of heatassociated deaths (e.g., age and gender) and the risk factors for mortality (e.g.,
homelessness). Sharing this information helps community stakeholders to design
interventions to prevent heat-associated deaths among vulnerable populations.
The two main sources of data for heat surveillance are preliminary reports of
death (PRODs) from the Office of the Medical Examiner (OME) and death
certificates from the MCDPH Office of Vital Registration.
Heat-associated deaths are classified as heat-caused or heat-related. Heatcaused deaths are those in which environmental heat was directly involved in the
sequence of events causing deaths. Heat-related deaths are those in which
environmental heat contributed to the deaths but was not in the sequence of
events causing these deaths. For more information on how heat-associated
deaths are classified, see the definitions in Appendix. For more information on
MCDPH’s surveillance system, see Background and Methodology.

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Heat Death Report | 2021

4

Results
Heat-Associated Deaths by Year
Graph 1. There were 339 heat-associated deaths reported in 2021, a 5% increase
from 2020 and a 70% increase from 2019.

323

339

199
179 182
154
75
21
2001

51 49

49 42

38

2003

2005

110

106

85

2007

74

76 61 84

82

2009

2011

2013

2015

2017

2019

2021

Graph 2. Fifty-seven percent of heat-associated deaths in 2021 have been
classified as heat-caused which is similar to the overall trend (61%) since 2006.

66
27
58

13
38

17
32

27
47

34
48

49

47

57

63

33
43

28
33

39
45

88

89
90

63
119

110

145

213

194

61
138

2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021
Heat-Caused

Heat
Related
Heat-Related

*Data Sources: Maricopa County, Office of Vital Registration and Office of Medical Examiner; Arizona Department of Health
Services, Office of Vital Registration
**See Methodology in the Appendix for more information about the number of confirmed, ruled-out, and pending cases by year

Heat Death Report | 2021

5

Heat-Associated Deaths by Month
Graph 3. Eighty-three percent of all heat associated deaths occured in the
months of June, July, and August (N=339).
32%
27%
24%
12%
4%
0%

April

May

June

July

August

September

0%

0%

October

Novermber

*Less than 1% of heat deaths occurred in the months of October and November
*Some deaths that occured in October and November were cases who suffered heat injuries during the summer

Graph 4. The highest proportion of heat-associated deaths typically occurs in July,
with 2021 have a lower proportion in July compared to previous years but a higher
than normal percent in June and September.
48%

38%

32%
29%

30%

27%

24%
17%

12%
7%
2%

March

7%

4%

6%

1%
April

May

June
2017

July
2018

Aug.
2019

2020

Sept.
2021

Oct.

1%
Nov.

Dec.

Heat Death Report| 2021

6

Heat-Associated Deaths and Temperatures
➢ In 2021, the National Weather Service issued six excessive heat warnings for a total of 20 days. The average number of heat warnings
for the past 5 years (2016-2020) is 7 for a total of 24 days.
➢ The highest daily temperature in 2021 occurred on June 17th and was 118°F, with 9 deaths occurring on this day. The average highest
daily temperature for the past 5 years (2016-2020) is 117°F. The highest daily temperatures ranged from 115°F to 119°F.
➢ For the past 5 years (2016-2020), an average of 34% of heat-associated deaths occurred on days for which an excessive heat warning
had been issued. In 2020, 52% of heat-associated deaths occurred on days for which an excessive heat warning had been issued.

Graph 5. Twenty-eight percent of heat-associated deaths occurred on days for which an excessive
heat warning had been issued (N=339).
16

120°F

14
100°F
80°F

10

60°F

8
6

40°F
4
20°F
0°F
4/10/2021

2
0
5/10/2021

6/10/2021

7/10/2021

Excessive Heat Warning
Daily Minimum Temperature

8/10/2021

9/10/2021

10/10/2021

Heat Associated Deaths
Daily Maximum Temperature

11/10/2021

Number of Deaths

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Heat Death Report | 2021

Demographic Characteristic of Heat-Associated Deaths
Graph 6. Males made up a higher proportion (81%) of all heat-associated
deaths.

Female
19%

Male
81%

Heat-Associated Deaths by Residency
Graph 7. Maricopa County residents accounted for eighty-six percent of
all heat-associated deaths amongst victims with a known county of
residence.
86%

Maricopa County Resident

6%

9%

Non-Maricopa County
Arizona Resident†

Non-Arizona Resident‡

† Non-Maricopa County Arizona resident cases include residents from Cochise, Coconino, La Paz, Navajo, Pima, Pinal, and Yavapai
Counties and cases of unknown county residency in Arizona. There were 15 Arizona residents with an unknown county residence.
‡ Non-Arizona resident cases include residents of Alabama, California, Colorado, Delaware, Florida, Georgia, Guatemala, Idaho,
Massachusetts, Minnesota, Mexico, Nevada, New Mexico, Ohio, Pennsylvania, Rhode Island, Tennessee, Washington. There
were 12 cases with an unknown state of residence.

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Heat Death Report| 2021

Graph 8. Sixty-six percent of heat-associated deaths with known residency
had lived in Arizona for 20 or more years at time of death.
66%

13%

<3 Years

9%

12%

3-9 Years

10-19 Years

20+ Years

*One-hundred-forty-five cases for which time spent in Arizona was unknown were excluded from analysis

Death Rates Among Maricopa County Residents
There was a total of 267 heat-associated deaths among Maricopa County residents. Heatassociated death rate graphs below represent rates per 100,000 residents. Rates were
calculated using 2020 Census demographic population estimates.

Graph 9. The heat-associated death rate for males in Maricopa County was more than three
times greater than the rate for females.

9.3

2.5

Males

Females

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Heat Death Report| 2021

Graph 10. Those aged 50-64 and 75+ had the highest rates of heat-associated
death.

9

14.2

11.0
9.8
6.1
3.8
0.4

0.1

0-4

5-19

20-34

35-49

50-64

65-74

75+

Age Group

Graph 11. For males, the heat-associated death rate was highest among the
50-64 year age group. For females, the heat-associated death rate was highest
among the 75+ year age group.
19.8
16.2

15.6

12.6
10.2
6.6
4.8
0.7

0.0

0-4

0.2

0.0

5-19

0.8
20-34

2.0

35-49

Males in MC (N=210)

2.6

50-64

65-74

Females in MC (N=57)

75+

Heat Death Report| 2021

Graph 12. African American and American Indian Maricopa County residents
had the highest heat-associated death rates per 100,000 people.

10

9
7
4
1

African American

American Indian

White Non-Hispanic

Hispanic

Asian/Pacific
Islander

*See specific profiles for more detailed information on African American, Hispanic, and American Indian heatassociated deaths.

Heat-Associated Deaths by Place of Injury
Table 1. The top 3 cities in Maricopa County with the highest heat-associated death rate per
100,000 people.
City

Number of Deaths

Rate per 100,000

Phoenix

178

11.1

Glendale

20

8.1

Tempe

12

6.6

*Rates based on US Census Bureau 2020 population rate by city.
**6 cases are unknown for place of injury city.

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Heat Death Report| 2021

Table 2. Top 5 ZIP codes in Maricopa County with the highest heat-associated death rates.
Zip Code

Number of Deaths

Rate per 100,000

85034

13

239.1

85007

15

101.2

85003

7

82.7

85009

19

35.2

85021

12

28.5

*6 cases are unknown for Zip code place of injury

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Heat Death Report| 2021

Graph 13. Since 2018, there has been a greater proportion of deaths occuring
outdoors compared to years prior.
Outdoor
2021

Indoor

75%

2020

25%

85%

15%

2019

76%

24%

2018

72%

28%

2017

60%

40%

2016

61%

39%

2015

61%

39%

2014

72%

28%

2013

59%

41%

2012

58%

42%

2011

46%

54%

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Heat Death Report| 2021

Graph 14. Males have a higher proportion of outdoors deaths compared
to females, while females have a higher proportion of indoor deaths.
78%

Male

Female

58%
39%

21%
3%

1%
Indoor

Outdoor

Unknown

*5 total cases have an unknown indoor/outdoor place of injury.
*See Indoor Heat-Associated Deaths profile and Outdoor Heat-Associated Deaths profile for more detailed
information on indoor and outdoor heat-associated deaths.

Graph 15. Fifty percent of indoor deaths were found during a welfare
check compared to five percent of outdoor deaths.

Outdoor Deaths 4%

Indoor Deaths

96%

52%

Welfare Check

48%

No Welfare Check

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Heat Death Report| 2021

Outdoor Deaths
 Fifty-one percent of male outdoor heat-associated deaths occurred in an urban area.
 Thirty-four percent of female outdoor heat-associated deaths occurred in an urban
area.
 Fifty percent of male outdoor heat-associated deaths were 50 years or older.
 Sixty-six percent of female outdoor heat-associated deaths were 50 years or older.
 Forty-four percent of male heat-associated deaths were of a racial minority group.
 Twenty-four percent of female heat-associated deaths were of a racial minority group.

Outdoor Demographics
*See Outdoor Heat-Associated Deaths profile for more detailed information on outdoor heat-associated deaths.
*Other includes park, highway, parking lot, and alley ways
**10 cases have an unknown outdoor injury place type
***See Vehicle Profile for more detailed information on heat-associated vehicle deaths

Graph 16. Forty-eight percent of outdoor injuries occurred in an urban area
such as a bus-stop or on the sidewalk.
Urban Area

48%

Desert Area/Hiking Trail

19%

Residence

13%

Vehicle

8%

Other

7%

Unknown

4%

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Heat Death Report| 2021

15

Graph 17. Outdoor heat deaths occured most often in July

32%

27%

25%

10%
4%
0%
April

May

June

July

August

September

0%

1%

October

November

Heat Death Report| 2021

Graph 18. The greatest number of deaths by week from an outdoor heat
injury happened during mid-June, early July, and late July.
4/11-4/17

0%

4/18-4/24
4/25-5/1
5/2-5/8
5/9-5/15

2%

5/16-5/22
5/23-5/29

1%

5/30-6/5
6/6-6/12

3%

6/13-6/19

10%

6/20-6/26

6%

6/27-7/3

8%

7/4-7/10

10%

7/11-7/17

6%

7/18-7/24

10%

7/25-7/31

2%

8/1-8/7

9%

8/8-8/14

6%

8/15-8/21

3%

8/22-8/28

5%

8/29-9/4
9/5-9/11

6%

9/12-9/18

2%

9/19-9/25
9/26-10/2

1%
0%

10/3-10/9
10/10-10/16
10/17-10/23
10/24-10/30
10/31-11/6
11/7-11/13
11/14-11/20
11/21-11/27

1%

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Heat Death Report| 2021

Indoor Deaths
Indoor Demographics
 Forty-six percent of indoor heat-associated deaths occurred among males aged 50-64
years old.
 Fifty-four percent of indoor heat-associated deaths occurred among females 75 years
or older.
 Thirty-seven percent of male indoor deaths occurred among people who are a minority
race.
 Twenty-three percent of female indoor deaths occurred among people who are a
minority race.
*See the Indoor Heat-Associated Death profile for more detailed information on indoor heat-associated deaths.

Graph 19. Forty-eight percent of indoor injuries with a known location of
injury occured in a house, while thirty-five percent occured in a
manufactured home which makes up about 5% of Maricopa County's
housing (n=82).
48%
35%

17%

Apartment/Condo

House

Manufactured

**Unknown Type of Residence is defined as an unspecified living space
***See Manufactured Home profile for more detailed information on manufactured home heat-associated deaths
****Manufactured homes were named mobile homes in previous heat reports

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Heat Death Report| 2021

Graph 20. Around half of the indoor heat deaths occured in a total span of
three weeks during mid to late June and mid July (n=82).
18%
15%
14%

8%

6%
5%

5%

4%

4%

4%

4%

3%

4% 4%

3%

1%

1%
0%

0%

Graph 21. Most indoor heat-associated deaths occured with indoor
temperatures between 90ºF and 109ºF, but can occur at temperatures as low
as 84ºF (n=82).
39%
34%

12%

84-89

90-99

100-109

7%

7%

110+

Unknown

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Heat Death Report| 2021

Air Conditioning Use for Indoor Injuries
*Evaporative coolers are not considered as A/C units as their ability to cool becomes inadequate in extreme heat.

Graph 22. Eighty-six percent of indoor heat deaths had an air
conditioning unit present at the time of death (N=80)*

A/C Not Present

14%

86%

A/C Present

*Two unknown cases were not included in the percent calculation .

Graph 23. Among deaths where an A/C unit was present, a non-functioning
A/C unit was the most common reason for not having a cooled environment at
the time of death (N=69)* .
Unknown Reason

3%
Not in Use

No Electricity

19%

3%

75%
Non-functioning A/C

*Two indoor heat deaths with no electricity occurred at the same
residence

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Heat Death Report| 2021

Substance Use among Heat-Associated Deaths
There were a total of 203 heat-associated deaths that involved substance-use that occurred in
Maricopa County for 2021. Substance use includes drugs and/or alcohol.

Graph 24. Sixty percent of all cases involved substance use as a cause of
death or a contributing factor.

No Substance
Use
40%

Substance Use
60%

*See Substance Use Profile for more detailed information on substance use heat-associated deaths

Graph 25. In seventy-seven percent of cases that involved substance use,
drug use was listed as either a cause of death or a contributing factor.
77%, 156

17%, 34
4%, 13
Drugs only

Alcohol only

Drugs and alcohol

*The types of drugs included in multiple drug toxicity cases were: Methamphetamine, Oxycodone, Fentanyl, Citalopram,
Opioids, Benzodiazepines, Lorazepam, Morphine, Hydroxyzine, Aripiprazole, Oxymorphone, Gabapentin, Cyclobenzaprine,
Diphenhydramine, and Carisoprodol

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Heat Death Report| 2021

Graph 26. Of the heat-related deaths where drugs were involved (N=169),
91% involved methamphetamine toxicity.
91%

30%

Methamphetamine

Fentanyl

3%

2%

1%

Cocaine

Methadone toxicity

Heroin

Graph 27. The proportion of heat-associated deaths involving drug use
decreased by three percent while the proportion involving alcohol use
increased four percent from last year.*

49%
46%
42%
37%

32%

24%
19%

18%

16%
13%

14%
16%

9%
10%
6%

8%

23%

23%

21%
13%

17%

16%

9%

10%

11%

16%

16%

13%

12%

10%

9%
6%

2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021
Alcohol

Drugs

*Does not include cases where both alcohol and drugs were involved in death.

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Heat Death Report| 2021

Graph 28. Of the heat-associated deaths where drugs were involved (N=169),
84% of the time drugs were a primary cause of death.

Drugs were related to
death

16%

84%
Drugs were a
cause of death

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Heat Death Report| 2021

23

Living Situation among Heat-Associated Deaths
Graph 29. Thirty-eight percent of cases were homeless at time of death.
Homeless

38%, 130

Living Independently

26%, 89

CoHabitating/Roommate

17%, 57

Unknown (NonHomeless)

9%, 31

Unknown

9%, 32

Graph 30. The number of heat-associated deaths among the homeless
population decreased 24% from 2020 to 2021, but it almost doubled from 2019.

116
177

53
32

45
6

46
3

53

60

21

22

86
20

90

55

20

20

54
7

76
8

100

122

121

133

54

57

61

66

172

130

2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021
Homeless

Non-Homeless

*32 cases where living situation was unknown were excluded from the homeless count
**16 homeless heat-associated deaths had an unknown county of residence
***See Homeless profile for more detailed information on homeless heat-associated deaths

Heat Death Report| 2021

Homeless Outdoor Death Demographics







Ninety-nine percent of homeless deaths occurred outdoors
Sixty percent of homeless outdoor deaths died in an urban area
Ninety-two percent of homeless outdoor deaths were male
Forty percent of homeless outdoor deaths were among 50-64 years old
Forty-nine percent of homeless outdoor deaths were among White Non-Hispanics;
twenty-three percent were among Hispanics, and eighteen percent were among Blacks

Graph 31. Sixty percent of homeless outdoor deaths (N=129) occurred
in an urban area.*
Urban Area

60%

Desert Area

19%

Car

8%

Residence

5%

Other

5%

Unknown

3%

*One homeless death is unknown for outdoor/indoor place of injury.

Education and Heat-Associated Deaths
Graph 32. 69% of the total number of heat-associated deaths where education
is known (N=280) have not received an education higher than a high school
diploma.
45%

10%

14%

16%

8th Grade or 9th-12th (No High School Some College
less
Diploma)
*56 cases have an unknown level of education
**Only adults aged ≥20 were included in these results

6%

6%

Associate

Bachelors

2%

1%

Masters

PhD

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Heat Death Report| 2021

Conclusions
 There was a 5% increase in heat-associated deaths between 2020 and 2021 and a
70% increase in heat-associated deaths between 2019 and 2021.
 In 2021, there was a total of 19 Excessive Heat Warning days, and on those days
25% of all heat-associated deaths occurred.

The average number of heat

warnings for the past 5 years (2017-2021) is lasting for a total of approximately 26
days.
 Most Arizona residents who died from heat-associated deaths lived here for more
than 20 years.
 Males, African Americans, American Indians, and those ages 75+ have the highest
rates of heat-associated death.
 Males had a 3x higher death rate than females per 100,000.
 The proportion of outdoor deaths was 75% compared to 25% for indoor deaths in
2021.
 Phoenix had the highest number of heat-associated deaths compared to all other
cities in Maricopa County.
 Forty-eight percent of heat-related injuries that happened outdoors occurred in an
urban area.
 Seventy-five percent of decedents who had A/C at the time of death were
reported as having a non-functioning A/C.
 Substance misuse was directly correlated with 60% of all heat deaths, 77% of which
involved drugs only.
 Methamphetamine was a contributing factor or main cause of death in 45% of all
heat-associated deaths.


Thirty-eight percent of heat-associated deaths occurred among the homeless
population.

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Heat Death Report| 2021

Appendices
Appendix 1 - Background and Methodology
Background
In July 2005, Maricopa County (MC) experienced exceptionally high temperatures that
contributed to 45 deaths, of which 35 occurred over nine consecutive days.
Temperatures reached 116° F and three excessive heat warnings were issued during this
month. After this event, the Maricopa County Department of Public Health (MCDPH)
created a novel and effective approach for surveillance of heat-associated deaths in
2006 and has continued to use this system annually.
Methodology

Surveillance data is obtained from the following sources:
1. The Maricopa County Office of the Medical Examiner (OME) forwards
suspected heat-related deaths to MCDPH and provides data including
demographics, preliminary information regarding how the death occurred,
and the circumstances of death. In the past, this information came solely
as a weekly line list with limited information for each case. However, in
February of 2012, MCDPH started receiving all preliminary reports of death
(PRODs) from the OME. These reports provide expanded information daily
and have changed the screening methods used by MCDPH staff to ensure
that all potential heat-related deaths are documented.
2. The MCDPH Office of Vital Registration registers all Maricopa County death
certificates in the Arizona Department of Health Services vital records
database. The MCDPH Office of Epidemiology searches this database
looking for causes of death associated with environmental heat. A
Statistical Analysis Software (SAS) program looks for the key phrases and
International Classification of Disease-10 (ICD-10) codes listed below.

26

Heat Death Report| 2021

Key Phrases

ICD 10
Code

HEAT EXPOSURE

X30

ENVIRON

T67.X

EXHAUSTION

P810

Corresponding Definition
Exposure to excessive natural
heat
Effects of heat and light
Environmental hyperthermia of
newborn

SUN
HEAT STRESS
HEAT STROKE
HYPERTHERMIA
3. Hospital and media reports can sometimes initiate a heat death
investigation, for example, if a child is reportedly left in a hot car.
Once data are received, analysis of the information is required to identify only
those deaths caused because of environmental heat. Environmental heat is heat
generated by the climate (sun, humidity, etc.) rather than heat from man-made
sources such as ovens or manufacturing equipment. Heat-associated deaths are
categorized based on the classification criteria listed below:
Heat-caused (HC) deaths are those in which environmental heat was directly
involved in the sequence of conditions causing deaths. These are deaths
where environmental heat terms were indicated in Part I1 of the death
certificate causes of death (diseases or conditions in the direct sequence
causing death), for cause of death variables (cod_a, cod_b, cod_c, or
cod_d). County of death: Maricopa.
Heat-related (HR) deaths are those in which environmental heat contributed
to the deaths but was not in the sequence of conditions causing these
deaths. These are cases where environmental heat terms were mentioned in
Part II2 of the death certificate causes of death (diseases and conditions
contributing but not directly resulting in the death sequence), but not in any
of the Part I death variables (cod_a, cod_b, cod_c, or cod_d). County of
death: Maricopa.
For the purposes of this report, heat-caused and heat-related deaths are
combined and referred to as “heat-associated deaths.” Please note that most
jurisdictions report only heat-caused deaths. This should be considered when
comparing Maricopa County data with data from other locations.

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Heat Death Report| 2021

Death certificate data, in combination with the OME notes, are used to produce
the information that is contained in this report. Total case count, demographics,
residency, drug/alcohol use, and years lived in Arizona are directly retrieved from
death certificate data. Place of death location, indoor/outdoor occurrence, air
conditioning use, and homelessness are retrieved based on explicit notations
made in the death certificate and/or OME notes. For the purposes of this report,
reasons for not having a cooled environment at the time of death in indoor cases
where an A/C unit was present were grouped into three categories: nonfunctioning, functioning but turned off, and no electricity. “Non-functioning” is
defined as an A/C unit that was not operating properly, was broken, or could not
be turned on despite the presence of electricity. Cases categorized as having a
“functioning but turned off” A/C unit indicates that the unit worked properly but
the A/C was turned off for some reason at the time of the OME scene inspection.
In cases where the unit could not be turned on due to a lack of electricity,
regardless of whether it was functioning or non-functioning, were counted in the
“no electricity” category.
Homelessness is defined as having an address on the death certificate that
matches a homeless shelter, government agency, business, or intersection. Cases
are also classified as homeless if there is an indication on the death certificate. If
the address is listed as unknown on the death certificate, then an examination of
the medical examiner’s notes is made to determine if there is a reference to an
address - if none, then the person is classified as homeless. If the address is listed
as out of jurisdiction, then time spent in Arizona, as provided by the death
certificate, is taken into consideration.
Once classification is completed, the data are summarized for the production
and dissemination of reports. Reports are generated weekly during the season
and posted to the MCDPH website which can be found at:
http://www.maricopa.gov/publichealth/Services/EPI/Reports/heat.aspx
1 Part I of the death certificate: cod a – is the immediate cause (final disease or

condition resulting in death) cod b, cod c, cod d – are sequentially listed
conditions leading to the cause listed on cod a.
2 Part II of the death certificate: Other significant conditions contributing to death

but not resulting in the underlying cause given in Part I.

28

Heat Death Report| 2021

To receive additional data, please submit a data request form through the
Maricopa County Public Health website here. A staff member from the Climate
and Health team will contact you to discuss your request.

You may also contact the Climate and Health Team through email:

Tianna Baker: Tianna.baker@maricopa.gov
Aaron Gettel: Aaron.gettel@maricopa.gov
Jackie Ward: Jackie.ward@maricopa.gov

29

Heat Death Report| 2021

Appendix 2 – Tables
Table 1.
Heat-Associated Deaths by Year

Year Number of deaths
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021

Under Investigation
21
38
49
42
75
85
51
49
74
82
106
110
75
61
84
154
179
182
199
323
339

0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0

30

Heat Death Report| 2021

31

Table 2.
Heat-Associated Deaths by Year
Year
Heat-Caused
Heat-Related
Total
2006
58
27
85
2007
38
13
51
2008
32
17
49
2009
47
27
74
2010
48
34
82
2011
57
49
106
2012
63
47
110
2013
42
33
75
2014
33
28
61
2015
45
39
84
2016
88
66
154
2017
90
89
179
2018
119
63
182
2019
138
61
199
2020
213
110
323
2021
194
145
339
TOTAL
1304
848
2152

Table 3.
Heat-Associated Deaths by Month and Classification, Maricopa County, 2021
March

April

May

June

July

August

September

October

November

December

Total

Heat-Related

0

1

5

39

45

32

22

1

0

0

145

Heat-Caused

0

0

9

53

62

48

19

1

2

0

194

Total

0

1

14

92

107

80

41

2

2

0

339

Heat Death Report| 2021

32

Table 4.
Heat-Associated Deaths by Year and Month
Years Jan
Feb March April May June July August Sept October November December Total
2007- 0
2009
2010- 1
2012
2013- 0
2015
2016- 0
2018
2019- 0
2021

0

0

1

5

27

84

39

14

4

0

0

174

0

1

1

7

51

109 93

28

4

3

0

298

0

3

2

5

49

89

49

20

2

1

0

220

0

3

3

17

122

200 113

45

7

4

1

515

0

0

5

29

140

342 248

84

10

3

0

861

Table 5.
Heat-Associated Deaths by Residency
NonMaricopa
Maricopa County
NonCounty
Arizona
Arizona
Resident Resident Resident Total
Total (N=339)

267

18

27

312

% of Cases

86%

6%

9% 100%

Unknown
27

Heat Death Report| 2021

33

Table 6.
Heat-Associated Deaths by Time Residing in Arizona*
Number of Deaths
n=339

Years in Arizona
<3 Years
3-9 Years
10-19 Years
20+ Years
Total
Unknown

% Deaths
25
18
23
128
194
145

13%
9%
12%
66%
100%
43%

Heat-Associated deaths by Demographic
Table 7.
Total Deaths by Gender
Gender
Male
Female

N

%
273
66

81%
19%

Table 8.
Total Deaths by Gender and Age Group
Age Group
0-4
5-19 20-34 35-49
50-64
65-74
75+
Unknown Total
Female
0
0
5
12
14
12
23
0
66
Male
2
1
51
60
99
34
26
0
273
Total
2
1
56
72
113
46
49
0
339
Percent
0.5% 0.2%
17%
21%
33%
14%
14%
0% 100%

Heat Death Report| 2021

Table 9.
Total Deaths by Race
Race
Asian/Pacific Islander
American Indian
African American
Hispanic
White
Total
Unknown

Heat-Associated Deaths
All Deaths (Incl Non-MC Res)
1%
5
7%
23
13%
45
18%
60
60%
205
100%
339
0%
1

Heat-Associated Death Rates
All populations based on US Census Bureau 2020 population counts.

Table 10.
Death Rates by Gender and Age
Gender
Male
Female
Age
Deaths Population Rate Deaths Population Rate
Group
0-4
1
139669
0.7
0
133513
0.0
5-19
1
461503
0.2
0
442721
0.0
20-34
33
498641
6.6
4
478914
0.8
35-49
45
439796 10.2
9
442250
2.0
50-64
78
394891 19.8
11
417371
2.6
65-74
30
192741 15.6
11
226935
4.8
75+
22
136195 16.2
22
173941 12.6
TOTAL
210
2263436
9.3
57
173941
2.5

34

Heat Death Report| 2021

Table 11.
Deaths Rate by Race
Race
% of all HeatRate per
MC
All MCR Deaths
Associated
100,000 MC
Population
Deaths for
residents
by Race
which race and
ethnicity are
known in MC
Asian/Pacific
1%
1
252864
3
Islander
American
5%
9
145400
13
Indian
African
13%
10
337871
34
American
Hispanic or
17%
4
1309888
46
Latino
White Non64%
7
2533058
171
Hispanic
Total
100%
267

Heat-Associated Deaths by Place of Injury
Table 12.
Gender and Place of Injury
POI
Male
Male N
Female
Female N Total
Indoor
21%
56
41%
26
82
Outdoor
79%
214
58%
38
252
Unknown
3
2
5
Total
273
66
339

35

Heat Death Report| 2021

Table 13.

36

Table 16.

Place of Injury by Year
Welfare Check

Year
Outdoor Indoor
Outdoor Indoor
2021
75%
25%
252
82
2020
85%
15%
271
46
2019
76%
24%
152
47
2018
72%
28%
128
51
2017
60%
40%
108
71
2016
61%
39%
93
59
2015
2014
2013
2012
2011

61%
72%
59%
58%
46%

39%
28%
41%
42%
54%

51
42
44
62
47

Yes
No
Total
Welfare Check
No Welfare
Check

33
16
30
45
56

*Unknowns not included in % calculations.

Table 14.
Outdoor Place of Injury
Place of Injury
(Outdoor)

N

%

Car

20

8%

Desert Area/Hiking
Trail
Residence

48

19%

34

14%

Urban Area/Park

122

49%

Unknown

10

4%

Other
Total

18
252

7%
100%

Table 15.
Indoor Place of Injury
Place of Injury (Indoor)

N

Mobile (Manufactured)
Home

29

House
Apartment/Condo
Total

39

14
82

%
35%
48%
17%
100%

Indoor Outdoor
Deaths Deaths
43
39
82
52%

9
243
252
4%

48%

96%

Heat Death Report| 2021

Air Conditioning Use for Indoor Injury
Table 17.
A/C Status
A/C Present (Indoor)

Number of
Cases

A/C Present
A/C Not Present
Total (not including unknowns)
Unknown

Percent
69
11
80
2

Table 18.
A/C Reason
Reasons for not having properly running AC

N

Non-Functioning
Not In Use
No Electricity
Unknown
Total

52
13
2
2
69

Substance Use among Heat-Associated Deaths
Table 19.
Substance use
Substance use
status
Substance Use
No Substance Use

N

%
203
136

60%
40%

Table 20.
Substance Type
Substance
Drugs only
Alcohol only
Drugs and alcohol
TOTAL

N

%
156
34
13
203

77%
17%
6%

86%
14%
100%

37

Heat Death Report| 2021

Table 21.
Type of Drug Used (Cause or Related to Death)
Drug Name
# of Cases
Cause of Death
Related to Death
Drug was
Involved in
Death
Methamphetamine
158
128
24
Cocaine
5
5
0
Fentanyl
50
44
6
Total
213
182
30

Table 22.
Substance Use by Year*
Year
Alcohol Percent Drugs
Percent
2006
14
16%
20
24%
2007
7
14%
*
6%
2008
*
10%
8
16%
2009
6
8%
7
9%
2010
13
16%
17
21%
2011
14
13%
10
9%
2012
14
13%
12
11%
2013
14
19%
13
17%
2014
6
10%
14
23%
2015
10
12%
15
18%
2016
25
16%
36
23%
2017
17
9%
57
32%
2018
30
16%
68
37%
2019
25
13%
84
42%
2020
19
6%
158
49%
2021
34
10%
156
46%
*Does not include cases where both alcohol and drugs were involved in the death.

38

Heat Death Report| 2021

39

Living Situation among Heat-Associated Deaths
Table 23.
Living Situation Type
Living Situation
Homeless
Living Independently
Co-Habiting/Roommate
Unknown (Non-Homeless)
Unknown
Total

N

%
130
89
57
31
32
339

38%
26%
17%
9%
9%
100%

Table 24.
Living Situation by Year*
2006

2007

2008

2009

2010

2011

2012

2013

2014

2015

2016

2017

2018

2019

2020

202

Homeless

32

6

*

21

22

20

20

20

7

8

54

57

61

66

172

130

NonHomeless

53

45

46

53

60

86

90

55

54

76

100

122

121

133

116

177

Percent
Homeless

38%

12%

6%

28%

27%

19%

18%

27%

11%

10%

35%

32%

34%

33%

60%

42%

*Does not include unknown living situation cases.

Education Level Among Heat-Associated Deaths
Table 25.
Education
Education Level
8th Grade or less
9th-12th (No
Diploma)
High School
Some College
Associate
Bachelors
Masters
PhD
Total

# of
% of Total
Deaths
Deaths
27
10%
40
128
45
17
17
5
2
281

14%
45%
16%
6%
6%
2%
1%
100%