Alberta Reports Surge in Deaths Due to ‘Unknown Causes’ in 2021

A police officer and a service dog walk past blossoming ornamental fruit trees during the COVID-19 pandemic in Calgary, Alta., on May 17, 2021. The Canadian Press/Jeff McIntosh

Recent data on the leading causes of death in Alberta show a spike in the 2021 mortality rate due to “ill-defined and unknown causes.”

The data, published on June 30 by Service Alberta, ranks the 30 most common causes of death in the province last year.

For the first time in the past twenty years, the category of “ill-defined and unknown causes of mortality” was the number one cause of death in 2021, resulting in a total 3,362 deaths, up from 1,464 in 2020, and 522 the year before that.

The unknown cause of death category emerged on the list in 2019, previously it had not been included in the ranking list dating back to 2001.

Dr. Daniel Gregson, an associate professor specializing in infectious diseases and microbiology at the University of Calgary, told CTV News that the reasons behind the emergence of the unknown causes of death category last year are “probably multifactorial.”

He said those factors may include a lack of medical resources to determine the cause of death, delayed access to healthcare services, and post-COVID complications.

Identified cases of COVID-19 are ranked as the third leading cause of death in Alberta in 2021 with 1,950 deaths—a jump from 1,084 in 2020 when the pandemic began.

From 2015 to 2020, organic dementia was listed as the leading cause of death in Alberta with chronic ischemic heart disease the dominant cause from 2001 to 2014.

In 2021, organic dementia came in second, contributing to 2,135 deaths, while chronic ischemic heart disease ranked fourth with 1,939.

Among the other top causes of death listed were: malignant neoplasms of trachea, bronchus and lung (1,552), acute myocardial infarction (1,075), chronic obstructive pulmonary disease (1,028), diabetes mellitus (728), stroke (612), and accidental poisoning by and exposure to drugs and other substances (604).