1. Improving Pneumonia and Influenza Mortality
Brandon Ramsey
Florida Department of Health
Heather Rubino
Janet Hamilton
David Atrubin
Improving Pneumonia and Influenza Mortality
Surveillance: Using Literal Cause of Death
Fields to Improve Accuracy and Timeliness
Mortality Data for Influenza Surveillance
DOH uses pneumonia and influenza (P&I) mortality as an indicator for influenza severity and for situational awareness.
International Classification of Disease (ICD- 10) codes are the most commonly used cause of death field.
Underlying ICD codes process slowly (see chart below) and can change over time.
DOH has access to the less commonly used literal cause of death (“literals”) fields via the state syndromic surveillance system (ESSENCE-FL), which are available hours after death.
“Literals” are causes of death that are physician-recorded at time of death (see comparison below).
Research Question
What are the benefits of using “literals” as opposed to underlying ICD code for mortality surveillance?
*Misspelled words excluded from table
Using the “literals” can increase the total number of pneumonia and influenza deaths identified.
Although the “literals” query for pneumonia is likely too broad, queries can be created to limit noise while still capturing all deaths of interest.
Creating specific queries makes it possible to include P&I-associated deaths even when they do not receive a P&I UCOD.
The “literals” help explain what caused a death with an “unspecified UCOD.”
Greater detail about deaths can improve analytic capacity to understand these events in terms of other conditions (see chart below).
Real-World Epidemiologic Applications
DOH uses a daily query of the literals to identify pediatric influenza deaths; often before ICD underlying cause of death is established.
Early detection of pediatric mortality increases the chance of retrieving and testing samples.
General P&I mortality is monitored weekly as a measure of influenza season severity.
Background
Methods
Results
Discussion
CONCLUSIONS
All death records from 2010 to 2014 (N=917,683) were obtained from Vital Statistics data using ESSENCE-FL.
Queries for influenza and pneumonia death detection were created (see below); one for underlying ICD code and one for “literals.”
The number of death records detected using the “literals” queries were compared to the number of deaths detected using the underlying cause of death ICD queries.
Deaths detected using the “literals” query were examined further to determine which ICD code they most frequently obtained as an Underlying Cause of Death (UCOD).
77% of influenza deaths detected with a “literals” query had a matching underlying influenza ICD code.
Top 5 ICD-10 Codes for Deaths with Influenza "Literals“
(Bold indicates “literals” and UCOD do not match)
Underlying ICD-10 Code
Deaths
ICD-10 Code Type
J110-With Pneumonia
168
Influenza
J111-With Other Respiratory Manifest 90
J09-Influenza due to identified avian influenza virus 87
J100-With Pneumonia Influ Virus 64
J101-With Other Resp Manifest Influ Virus 46
Words within “Literals” of Influenza Deaths
Queries Used in Analysis
“Literals” Query for Influenza*
UCOD Query for Influenza
Terms
Negations
Influenza, H1N1
Haemophilus, Fluid, Flutter, Non-flu, Bacteremia, Flur, Conflu, Fluo
J09, J10, J11 -
24% of pneumonia deaths detected with a “literals” query had a matching underlying pneumonia ICD code.
Example Death Record: “Literals” and Underlying ICD Code
"literal" 1
"literal“ 2
"literal" 3
"literal" 4
Underlying Cause
Pneumonia
Flu
COPD
None
J110
(Influenza with Pneumonia)
Top 5 ICD-10 Codes for Deaths with Pneumonia "Literals“
(Bold indicates “literals” and UCOD do not match)
Underlying ICD-10 Code
Deaths
ICD-10 Code Type
J189-Unspecified
10,413
Pneumonia
J440-With Acute Lower Respiratory Infection
5,704
Not Pneumonia
F03-Unspecified Dementia
2,833
C349-Unspecified
2,513
I251-Atherosclerotic Heart Disease
1,730
“Literals” Query for Pneumonia*
UCOD Query for Pneumonia
Terms
Negations
Pneumonia
Aspir, Pneumonitis, Pneumococcal
J12, J13, J14, J15, J16, J17, J18 -