The self-controlled case series study in Florida that shows increased risk of cardiac-related death

Here's what it all means...

There was a study done recently related to COVID-19 injection adverse event eventuality by analysts in the State of Florida entitled: “Exploring the relationship between all-cause and cardiac-related mortality following COVID-19 vaccination or infection in Florida residents: a self-controlled case series study”. This study used an analytical technique called self-controlled case series¹ which is a technique for assessing associations between transient exposures (say, to a vaccine) and an adverse event occurrence. It is a powerful technique in that the controls are built-in - each individual included in the study comprises a case (individuals who have experienced the outcome of interest) with an observation time divided into control and risk periods, depending on when they were injected with a biological, in this case.

What is the self-controlled case series method?
​The self-controlled case series (SCCS) method is an alternative study method for investigating the association between a transient exposure and an adverse event. The method was developed to study adverse reactions to vaccines. The method uses only cases, no separate controls are required as the cases act as their own controls. Each case’s given observation time is divided into control and risk periods. Risk periods are defined during or after the exposure. Then the method finds a relative incidence, that is, the incidence in risk periods relative to the incidence in control periods. Time-varying confounding factors such as age can be allowed for by dividing up the observation period further into age categories. An advantage of the method is that confounding factors that do not vary with time, such as genetics, location, socio-economic status are controlled for implicitly.²

The exposure data was collected for the 28-day risk period following the most recent COVID-19 injection (of a possible 2) whereby two outcomes were assessed: natural all-cause deaths and cardiac-related deaths.³ The authors found that within this 28-day risk window, both all-cause and cardiac-related death risk were substantially higher.

According to Table 2 in the report, there was an 84% increase in relative incidence of cardiac-related deaths following COVID-19 injection for males ages 18-39 who were injected with the mRNA products. This is quite astounding, and alarming, to say the least. It is also aligned with my own findings pertaining to multi-fold increases in reports of myocarditis in VAERS in young males.

Figure 1: Table 2: https://floridahealthcovid19.gov/wp-content/uploads/2022/10/20221007-guidance-mrna-covid19-vaccines-analysis.pdf.

I have downloaded the R package SCCS in an attempt to reproduce the calculations herein, but this might take time. Like: forever. So don’t hold your collective breaths.

As the authors point out, there are study limitations herein, and I would be interested to see this type of methodology reproduced using other and larger datasets. I would also like to see a study that expands the timeframe beyond the 28-day window.

You can also go to Jeff Childer’s write-up for even more good news.

1. Whitaker, H.J., Paddy Farrington, C., Spiessens, B. and Musonda, P. (2006), Tutorial in biostatistics: the self-controlled case series method. Statist. Med., 25: 1768-1797. https://doi.org/10.1002/sim.2302.

2. https://sccs-studies.info/index.html

3. Cardiac-related deaths were included if their death record contained an ICD-10 code of I30-I52.