1. Utilization of GIS to identify ‘hot spot’ zip codes for prescription fatal drug overdoses in Maricopa County
By William McConahey

2. Why is it a public health
and social concern?
Poisonings became the leading cause of injury death in the US (2008)1
Most poisoning deaths due to drugs1
Last 3 decades drug poisoning deaths have increased 7x from 1980 to 20131
51% of all drug poisoning deaths are related to RX drugs- opioid pain relievers (OPR) were the majority (75%)1

3. The danger of OPR abuse OPR1 Commonly used and highly available
Pain- hydrocodone, methadone, oxycodone
More OPR deaths >> than heroin & cocaine combined.
A precursor to heroin use
Each day, 44 people in the US die from OPR
16,000 per year, increase 4x since 1999 (2014)

4. Drug poisoning trends in the United States, 1980-2010
Death Rates2
h Rates
Number of overdoses
BY INTENT2

5. Percentage of pills prescribed by drug type in arizona, 20123
RX misuse and abuse
in Arizona
Quick facts
Percentage of pills prescribed by drug type in arizona, 20123
AZ is 12th highest state in US for RX drug misuse and abuse among 12+ (NSDUH, 2013).
AZ is 12th highest state for drug overdose mortality (CDC, 2014)
58% of pills prescribed in AZ are opiates

6. The AZ RX Misuse & Abuse Initiative
Multi-agency Approach3
Stakeholder Collaboration
Goal3
Reduce RX nonmedical misuse, abuse, and deaths by 18% by 2018
Strategies3
Reduce illegal acquisition/diversion of RX
Promote responsible prescribing/dispensing RX
Enhance RX practices/policies in law enforcement
Increase public awareness about RX misuse
Increase assessment/referral to treatment

7. Overview of countywide RX monitoring initiatives
Awarded the Harold Rogers Prescription Drug Monitoring Grant from U.S. Department of Justice (2014)3
Previously piloted in Yavapai, Pinal, Graham/Greenlee, & Mohave3
Based on criteria: evidence of RX problem, willingness to use data-driven decision making, and capacity for implementation
By end of 2-year pilot study, deaths and ER visits were reduced and prescription drug monitoring program (PDMP) usage & RX awareness increased

8. Maricopa County implementation of AZ RX Misuse and Abuse Initiative
Partnership for Arizona RX misuse and abuse initiative
Arizona Criminal Justice Commission (ACJC)
Mercy Maricopa Integrated Care
Maricopa County Department of Public Health (MCDPH)
MCDPH focus
increase public awareness
patient education
gather data regarding nonmedical misuse and abuse of drugs resulting in fatal and non-fatal overdoses
Office of Epidemiology
Utilize GIS to find areas in county with highest number of deaths

9. Study purpose
Identify patterns and trends for fatal overdoses in Maricopa County from
Analyze opiate frequency and rates within zip codes

10. Methodology
Vital Data (Death Certificates) for Maricopa County Residents from
ICD-10-CM codes were used to identify primary cause of death for poisonings (X40--X44, X60--X64, X85, or Y10--Y14.)
All other 20 diagnosis fields were analyzed for the following drug overdoses: Opiate (T ), Benzodiazepine (T42.4), Cocaine (T40.5), and Heroin (T40.1)
Used ArcGIS software to map zip codes, and excluded P.O Boxes and to manipulate and analyze original data

11. Kernel Density Tool in Spatial Analyst toolbox
calculates prevalence per unit area from point or linear feature using a kernel function to fit a smooth surface to each point or line
Calculates points that fall within the neighborhood considered in calculating density

12. Kernel Density

13. Kernel Density example
Group of points are converted into a single raster

14. Hot Spot Analysis Tool in Spatial Statistics toolbox
identifies statistically significant hot spots and cold spots using Getis-Ord Gi* statistic based on a null hypothesis
Creates a new output feature class with a z-score, p-value, and confidence level
P-value-probability of random spatial pattern
Z-score-standard deviation from mean value

15. Hot Spot Analysis

16. Hot Spot Analysis

17. Hot Spot Analysis example

18. Drug death numbers in Maricopa County, AZ (2008-2013)
Note: Drugs in this graph are combined total of deaths due to benzodiazepine,
cocaine, heroin, and opiate use.

22. Opiates
Emphasis on opiates due to more widespread use than other drugs
Questions to address
What areas (zip codes) have the highest fatal overdoses for opiates from ?
Do socioeconomic factors have an effect on fatal opiate overdoses?

23. Density map for drug deaths

24. Zip codes with highest drug death frequency

26. Zip Codes with highest frequencies for both studied drugs and opiate deaths: 85018, 85032, 85225

27. Frequency of opiate deaths by zip code
PHOENIX
NON-PHOENIX
Zip Code
Frequency
85018 29
85032 28
85022 22
85021 20
85023
Zip Code
Frequency
85345 28
85301
85225 24
85281 22
85308 21

29. Poverty rate in zip codes with opiate death hot spots
85308
7.3
85225
16.5
85302
85018
85345
16.8
85022
17.4
85281
38.9
85301
39.1
Median hot spot poverty rate: 16.7% (Countywide poverty rate: 16.7%)
Note: 2010 poverty rate is official figure from US Census Bureau

30. Median household income in zip codes with opiate death hot spots
85301
27,267
85302
43,477
85022
45,606
85345
45,886
85018
52,389
85225
56,414
85281
57,348
85308
68,796
Median household income for hot spots :$50,425
Median household income for Maricopa County: $53,596

31. Frequency changes in opiate deaths
for Maricopa County

32. Frequency changes of opiate deaths in hot spot zip codes (2008-2013)

33. Summary of opiate death frequency
Was there a significant relationship between poverty rate, median household income, and opiate death frequency? Based on existing data, no
Was there a general drop in opiate deaths between 2008 and 2013? Yes

34. Drug death rate by zip code

36. Zip Codes with highest rates for studied drug deaths and opiate deaths: 85004, 85013, 85014, 85342

37. Opiate death rate by zip code
PHOENIX
NON-PHOENIX
Zip Code
Rate
85004
120.8
85018
80.4
85014
76.7
85023
64.0
85013
57.0
Zip Code
Rate
85342
126.7
85264
80.1
85378
70.1
85302
54.2
85306
53.7

39. Poverty rate in zip code with opiate death rate hot spots
85023
16.2
85342
16.6
85018
85014
24.4
85264
24.5
85004
39.8
Median poverty rate: 20.5% (Countywide poverty rate: 16.7%)
Note: Poverty rate was based on 2010 Census data.

40. Median household income in zip codes with opiate death rate hot spots
85004
26,008
85014
41,903
85342
42,375
85023
47,200
85018
52,389
85264
56,842
Median household income in hot spots: $44,788
Median household income for Maricopa County: $53,596

41. Rate changes in opiate deaths
in Maricopa County

42. Rate changes in opiate deaths in hot spot zip codes

43. Summary of opiate death rates
Was there a significant relationship between poverty rate, median household income, and opiate death rate? No, although poverty rate was higher and median household income was lower compared to areas of high opiate death frequency
Did the rate of opiate deaths drop between 2008 and 2013? According to the existing data, yes

44. Findings and Conclusions
The top zip codes for opiate death frequency and rates were different, probably due to different population numbers within each zip code
Frequency and rates of deaths due to opiate use declined between 2008 and 2013
Poverty rates and median household incomes varied greatly within hot spots, which indicates they may be a factor, but not a significant factor, in determining opiate death occurrences within a given population

46. William McConahey GIS Epidemiologist
Maricopa County Department of Public Health

47. Footnotes
1Warner M, Chen LH, Makuc DM. Drug Poisoning Deaths  in the United States, 1980–2008. NCHS data brief, no 81. Hyattsville, MD: National Center for Health Statistics Centers for Disease Control and Prevention. Injury Prevention & Control: Prescription Drug Overdose. (2015). Available from URL

48. Footnotes
2Jones C. Prescription Drug Abuse and Overdose in the United States.  (2013). Available from URL
3Malone S. A Multi-Systemic Approach for Address for Arizona’s “ Silent Epidemic”. (2014). Arizona Criminal Justice Commission: Statistical Analysis Center