Cold-related Illness

Cold-related illness is a weather-related condition that occurs when the body is exposed to cold temperatures for a long period of time. Prolonged exposure to the cold can be dangerous and life-threatening. The most common cold-related illnesses in Maine are hypothermia and frostbite. Tracking emergency department visits and hospitalizations for cold-related illness helps to understand how Mainers are affected by exposure to cold temperatures.

What data are available?

Maine tracks the following measures associated with cold-related illness:

Near real-time data (daily emergency department visits)
Emergency department (ED) visits (annual summaries)
Hospitalizations

Cold-related Illness Emergency Department (ED) Visits

This display shows the number and rate of cold-related illness emergency department (ED) visits per 100,000 population. These data can tell us which counties have a higher number or rate of ED visits and if a rate is going up or down over time. To add a county to the trend chart, click a county on the map. To unselect a county, click the same county again.

Cold-related Illness Hospitalizations

This display shows the number and rate of cold-related illness hospitalizations per 100,000 population. These data can tell us which counties have a higher number or rate of hospitalizations and if a rate is going up or down over time. To add a county to the trend chart, click a county on the map. To unselect a county, click the same county again.

Cold-related Illness Trends

This display shows trends over the years in cold-related illness emergency department (ED) visits and hospitalizations. These data can tell you if a segment of a population (by sex or age) is at higher risk for a visit to the ED or hospitalization for cold-related illness.

Cold-related Illness Tables

Create a custom table of data about cold-related illness emergency department (ED) visits or hospitalizations.

Measure Definitions

Near Real-time Emergency Department Visits and Temperature
- Near real-time cold-related illness data are from Maine’s syndromic surveillance system, which gathers and aggregates data from emergency department visits from hospitals in Maine. Visits are counted as cold-related based on a syndrome definition that uses a combination of keyword searches of a patient’s chief complaint along with relevant diagnosis codes.
- Temperature data are supplied by the Maine Climate Office at the University of Maine’s Climate Change Institute (https://mco.umaine.edu). The daily minimum and maximum temperatures represent the lowest AM and highest PM values within each day. Apparent maximum and apparent minimum are the “feels like” temperatures which account for humidity and wind speed. Temperature data are population weighted, to best represent population exposures.
- Cold-related illness visits are analyzed by county of residence (where the patient lives) and county of care (where the patient was treated). Place of residence analyses are restricted to Maine residents, whereas place of care analyses include anyone who was treated at a Maine facility. Percentages represent the number of cold-related visits compared to all emergency department visits, which allows for comparisons while accounting for population or utilization differences. Sagadahoc county does not have a hospital and does not show on the map when data are shown by place of care.

Emergency Department Visits and Hospitalizations
- Visits with a primary or secondary diagnosis of cold-related illness (e.g. hypothermia, frostbite) are included in the analysis.
- Data for 2015 are not shown because hospitalization diagnostic coding transitioned from the International Classification of Diseases, 9th Edition, Clinical Modification (ICD-9-CM) to the 10th Edition (ICD-10-CM) in October 2015. Caution is advised when comparing rates in years before 2015 to rates after 2016 due to the coding change.
- Analyses are based on the year of admission to an emergency department or hospital.
- Cold-related illness visits are analyzed by place of residence (where the patient lives) and place of care (where the patient was treated). Place of residence analyses are restricted to Maine residents in order to calculate rates per population. Place of care analyses are not restricted to Maine residents, and only displayed as counts (Number). Use place of residence to compare rates across the state. Use place of care to view the burden (total number) of cold-related illness visits.

Data Limitations

Near Real-time Emergency Department Visits and Temperature
- Syndrome definitions using key words are imperfect, and occasionally include non-cold-related visits or mistakenly exclude cold-related visits.
- ED visit data do not include visits to the Veteran’s Affairs hospital in Maine or the Indian Health Service.
Emergency Department Visits and Hospitalizations
- Visits associated with Maine’s Veteran’s Affairs Hospital and the Indian Health Service are not included.
- Due to the transition from ICD-9-CM coding practices to ICD-10-CM, 2015 data are not included.
- Only Maine residents seen at Maine hospitals are included when data are analyzed by place of residence. Out-of-state residents are included when data are analyzed by place of care.

Additional Details

In order to protect privacy as per the Maine CDC Privacy Policy, data may have been suppressed. For locations where data must be suppressed a range (e.g. 1-5) is provided for the number of events and an asterisk (*) for the rate. Data may be secondarily suppressed to prevent indirect identification and displayed as not reported (NR).
Age-adjusted rates are considered unreliable and not reported (NR) when case counts are less than 25.
Combined year population data are the sum of individual years (e.g., 2010-2014 is the sum of populations in 2010, 2011, 2012, 2013, and 2014). Combined year rates are annualized across all included years.

Environmental Public Health