About Asthma
Overview
This site provides data on the number and rate of asthma hospitalizations and emergency department (ED) visits in New York State (NYS). These data are presented by age groups, sex, ethnicity, and total population for various time frames. The table below shows key information about asthma ED visits and hospitalization data.
| Data Source | Statewide Planning and Research Cooperative System (SPARCS) |
|---|---|
| Data type | Hospitalizations and Emergency Department Visits |
| Timeframe | Hospitalizations 2000-2019 Emergency Department Visits 2005-2019 |
| Geographic Coverage | New York State by region, county, and sub-county |
| ICD-9-CM Code & ICD-10-CM Code | ICD-9: Primary diagnosis code of 493 ICD-10: Primary diagnosis code that starts with J45 (18 codes) |
| Last Update | February 2025 |
Interpreting Data
These data include people who had an asthma episode that was serious enough to require an ED visit or hospitalization in NYS but may also reflect factors related to access to health care that result in some people seeking care at a hospital rather than a primary care physician. The data excludes people who received asthma care and management through a visit to a primary care physician. The data show the number of asthma ED visits and hospitalizations that occurred rather than the number of patients who were admitted or seen for asthma related illness. For example, if a person was hospitalized twice, they would be counted twice.
ED visit counts are based on ED visit date and hospitalization counts are based on hospital admission date. The data are displayed as crude and age-adjusted rates of ED visits and hospitalizations among NYS residents by county and sub-county aggregated areas. Read the technical notes to learn more about how sub-county areas in NYS were developed by the NYS Environmental Public Health Tracking program.
Calculating Rates
Crude Rates
Crude rates provide a general idea of how common a health outcome is occurring in a population. However, the crude rate does not account for other factors such as the age or sex distribution of a population. Crude rates per 10,000 people were calculated by dividing the number of cases in the area by the total estimated population then multiplying by 10,000. For crude rates calculated across multiple years, the total number of cases and the population were first summed across multiple years. The average annual crude rate was then determined by dividing the summed cases by the summed population and multiplying the result by 10,000. These calculations were performed in the same manner for state, region, county, and sub-county analyses.
Age-Adjusted Rates
Age-adjusted rates allow users to compare areas with different age distributions. This helps to account for differences in the rates of health outcomes across age groups. The age-adjusted rates presented on the EPHTracker use the age distribution for the total population of NYS as a reference in calculations. Age-adjusted rates per 10,000 were calculated by first dividing the total number of cases by the total estimated population for each five-year age group. These five-year age group-specific rates were then multiplied by the NYS age group-specific weights (i.e. the proportion of the population in each age group). Because of smaller numbers of health outcomes, for sub-county age-adjusted rates four age groups (‘0-4’, ‘5-14’, ‘15-64’, and ‘65 and above’) were used to calculate age-specific rates (i.e. rather than five-year age groups). All weighted age-specific results were summed and multiplied by 10,000. For age-adjusted rates calculated across multiple years, the average age-specific rate was first calculated for the years of interest, then multiplied by the NYS age-specific weights for that age group, and subsequently multiplied by 10,000.
Maps, Charts and Tables
Maps and Tables
Maps and tables of statewide asthma ED visits and hospitalizations are available by age-adjusted and crude rates for user-selected time frames. Users can compare asthma ED visit and hospitalization rates across counties and sub-county areas in the following regions: New York State (whole state), New York City (NYC), New York State Excluding New York City. Selecting the “NYS excluding NYC” option allows the user to clearly see differences in ED/Hospitalization rates between areas outside of NYC.
View by County/Sub-County
- Asthma Age-Adjusted ED Visits/Hospitalizations Rate
- Asthma Crude ED Visits/Hospitalizations Rate
Charts
Charts of statewide and regional asthma ED visits and hospitalizations age-specific/adjusted and crude rates are available by demographic characteristics of age group, age group and sex, age group and race, and age group and ethnicity for user-selected year ranges of at least five years.
Age-specific rates per 10,000 population are displayed for the following age groups for all age group charts: 0-4 years, 5-14 years, 15-19 years, 20-24 years, 25-64 years, and 65+ years. Users can compare asthma ED visits and hospitalization rates across following regions: New York State (whole state), New York City, New York State excluding New York City. Selecting the “NYS excluding NYC” option allows the user to more clearly see differences in ED/Hospitalization rates between areas outside of NYC.
View by Region/State
- Asthma ED Visits/Hospitalizations by Age Group
- Asthma ED Visits/Hospitalizations by Age Group and Sex
- Asthma ED Visits/Hospitalizations by Age Group and Ethnicity
About Unstable Rates
When an ED visit or hospitalization rate is based on small numbers, an increase or decrease of just one or two cases from year to year can cause the ED visit or hospitalization rate to change dramatically; such a rate is likely to be unstable. Unstable ED visit or hospitalization rates are accompanied by the symbol in the map, a hover-over pop-up shows when the rate is based on 11 to 20 cases. These rates should be interpreted with caution. Additionally, a rate is not calculated if there are 10 or fewer cases, as the number is too small to produce a reliable estimate.
Additional Information
- In October 2015, reporting of diagnosis codes in the hospitalization and ED visit datasets switched from International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) coding to International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) coding. This may result in apparent changes in trends between 2015 and 2016 that are due solely to the switch from ICD-9-CM to ICD-10-CM.
- For ED visits and Hospitalizations that had a hospital admission date before October 1, 2015: An Asthma ED visit or hospitalization is defined as having a principal diagnosis with an International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) code of 493.
- For ED visits and Hospitalizations that had a hospital admission date on or after October 1, 2015: An Asthma ED visit or hospitalization is defined as having a principal diagnosis with an International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) code that starts with J45 (18 codes).
- Population estimates used for calculating asthma ED visits and hospitalization rates were taken from the U.S. Census Bureau. State ED visits and hospitalization rates are based on State Population Estimates File, available at Population Estimates Data Sets . New York State county level ED visits and hospitalization rates are based on County Resident Population Estimates File, available at Population Estimates Data Sets .
- Adjusted rates were calculated using a standard NYS population for 2008-2012 based on NYS estimated populations.
