COVID-19 Vaccine and BMI

As the COVID-19 pandemic has progressed, we have learned much about the virus, the disease process, its complications and management, and who is most severely affected by it.

Obesity, defined as a body mass index (BMI) of 30 or greater, has become a well-recognized risk factor for severe COVID-19-related illness. This has dramatic public health implications considering that over 42% of the US population is affected by obesity.

BMI is a calculation based on a person’s weight and height. You can calculate your BMI with the NIH’s calculator here: https://www.nhlbi.nih.gov/health/educational/lose_wt/BMI/bmicalc.htm.

While obesity is a strong risk factor for severe COVID-19 related illness, does having obesity affect when you are eligible to receive the COVID-19 vaccine?

First, we will look at the current recommendations for vaccine eligibility in general and where these recommendations came from.

Second, we will look at COVID-19 vaccine eligibility and BMI in particular.

The Centers for Disease Control and Prevention (CDC) first offered recommendations for the COVID-19 vaccine rollout based on various eligibility criteria in December of 2020. The recommendations are based on guidance from the Advisory Committee on Immunization Practices (ACIP). The ACIP received input from the public as well as from Johns Hopkins Bloomberg School of Public Health; The National Academies of Sciences, Engineering, and Medicine; and the World Health Organization (WHO) Strategic Advisory Group of Experts (SAGE).

The priority for vaccine administration is based on a phased approach. Groups in Phase 1a should be offered the COVID-19 vaccine first followed by those in Phase 1b and then Phase 1c.

In Phase 1a are healthcare personnel and residents of long-term care facilities. Phase 1b consists of frontline essential workers and people aged 75 or older. Phase 1c includes people aged 16-64 with underlying medical conditions, people aged 65-74, and essential workers not covered in phase 1b.

To qualify as an underlying medical condition, the condition must place a person at increased risk of “severe illness” from COVID-19 infection. The CDC defines “severe illness” as illness that leads to hospitalization, admission to the intensive care unit, intubation or mechanical ventilation, or death.

Obesity (BMI of 30 or greater) and severe obesity (BMI of 40 or greater) are two of these significant underlying medical conditions. People with overweight (BMI of 25 or greater) might be at greater risk for severe illness according to the CDC.

It is important to note that each state independently develops its own plan for COVID-19 vaccine eligibility which may or may not follow the CDC’s recommendations. Further, individual vaccination sites may have their own rules for prioritizing vaccine administration. At the time of this writing, at least 29 states have expanded vaccine eligibility to include those with a BMI greater than 30. You can contact your local health department for information on vaccine eligibility in your area.

We have established that obesity is considered an underlying condition that places a person at high risk of serious illness from COVID-19 infection, and therefore people with a BMI greater than 30 should be included in phase 1b of the COVID-19 vaccine rollout.

Now, let’s look at why obesity is considered a significant underlying condition that warrants Phase 1b vaccine eligibility.

The CDC’s Morbidity and Mortality Weekly Report from March 12th, 2021 summarized the impact of overweight and obesity on COVID-19 illness severity from the earliest days of the pandemic through the end of 2020. This report analyzed data from almost 150,000 people diagnosed with COVID-19 infection and concluded that obesity is a clear risk factor for hospitalization and death. The risk was more pronounced for those under age 65. Both overweight and obesity were risk factors for requiring mechanical ventilation.

The authors concluded that the findings of this study highlight the need for intensive management of COVID-19-associated illness and vaccine prioritization for those with obesity.

In summary, those with a BMI of greater than 30 are eligible for the COVID-19 vaccine during Phase 1b of the vaccine rollout according to the CDC recommendations. However, eligibility rules vary by state and by vaccination site, so contact your local health department for information about eligibility in your area.