Non-peer reviewed, preliminary study compares COVID-19 mortality rates in Norway and Sweden

Important note: medRxiv, the study this article sources information from, publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.

A study titled Mortality in Norway and Sweden before and after the Covid-19 outbreak: a cohort study has been published online, funded by the Norwegian Research Council and Norwegian Cancer Society.

An initial question regarding the study could be raised: How can mortality after the pandemic be measured, given that it’s ongoing?

Let’s take a look at some of the findings of this preliminary study.

The goal

The study’s researchers compared the effect national strategies had on COVID-19-associated mortality in Norway and Sweden.

The two countries were chosen are similar in regards to ethnicity, healthcare, and socioeconomic stability.

Their COVID-19 responses were vastly different in 2020 at the time of the study, however, with Norway opting for stricter lockdowns while Sweden took on a more relaxed approach.

The parameters

Weekly mortality rates with 95% confidence intervals were calculated to compare the following time periods:

July 29, 2019 to July 26, 2020

with

July 2015 to July 2019.

COVID-19-associated deaths and mortality rates were compared for Norway and Sweden for the following time periods, as well:

March 16, 2020 to July 26, 2020.

The results

Norway’s mortality rates

General mortality rates during the first three 12-month periods of 2015/16, 2016/17 and 2017/18:

• 14.8 to 15.1 per 100,000

General mortality rates during the two most recent periods including during epidemic period 2018/19 and 2019/20:

• 14.5 per 100,000

COVID-19-associated mortality rates from March 16, 2020 to July 26, 2020:

• 0.2 per 100,000

Sweden’s mortality rates

General mortality rates during the first three 12-month periods of 2015/16, 2016/17 and 2017/18:

• 17.2 to 17.5 per 100,000

General mortality rates during the two most recent periods including during epidemic period 2018/19 and 2019/20:

• 16.2 per 100,000

COVID-19-associated mortality rates from March 16, 2020 to July 26, 2020:

• 2.9 per 100,000

Note: The increase in mortality for both was confined to individuals aged 70 years and up.

The conclusions

General mortality rates remained the same in Norway.

There was an increase in general mortality during the COVID-19 pandemic. The authors attribute this partly due to a lower-than-expected mortality rate in Sweden prior to the pandemic. After the first COVID-19 wave, there was apparently again a lower-than-expected mortality rate.

To explain these discrepancies, the authors call upon potential mortality displacement:

“Our study shows that all-cause mortality was largely unchanged during the epidemic as compared to the previous four years in Norway and Sweden, two countries which employed very different strategies against the epidemic.”

Dr. Tomislav Meštrović, MD, Ph.D explains mortality displacement in the context of this study:

“More specifically, mortality displacement implies temporarily increased mortality (i.e., excess mortality) in a certain population as a result of external events, which likely arises because individuals in vulnerable groups die weeks or months earlier than they would otherwise – primarily due to the timing or severity of the unusual external event.

The excess mortality is, thus, predated or followed by time periods of lower than expected mortality.

In conclusion, the researchers hope that these findings can open the door for a less polarized and non-judgmental discussion about the benefits and drawbacks of either more lenient or more drastic measures against the COVID-19 pandemic.”

Read the full report here – and let us know what you think.

Source: #Norway Today, #NorwayTodayNews, medRxiv

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