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The near-daily COVID-19 briefings by Minnesota health officials provide a deluge of data points about this viral disease and its spread across the state. But few figures have stood out as sharply as this one:

Of all those who have died from the mysterious viral illness statewide, 99.24% had an underlying health condition.

When there's no proven treatment for COVID-19 and no vaccine, it's tempting to succumb to the potentially false reassurance offered by both this eye-grabbing statistic and the vagueness of the "underlying condition" category. Without further scrutiny, it may seem that only those who are elderly or acutely ill are vulnerable.

The reality: Many of those who lead normal lives despite having common, treatable chronic conditions — high blood pressure is a prominent example — appear to be at higher risk for becoming seriously ill or dying after becoming infected with this new strain of coronavirus. As mitigation measures begin to ease, it's critically important to understand individual susceptibilities. Your risk, or that of a loved one, may be higher than previously realized.

The state has a useful dashboard of COVID-19 information. But it doesn't list underlying health conditions for those who have become severely ill or passed away — an information gap that should be filled.

The New York State Department of Health does track some of this information for that hard-hit state. Of the 20,828 fatalities listed on Friday, 89.4% had at least one underlying health condition, also known as a "co-morbidity." Hypertension (high blood pressure) is by far the most common. Rounding out the top five are diabetes, hyperlipidemia (high cholesterol), dementia and coronary artery disease.

A recent study published in the medical journal JAMA raised concerns about other common health conditions. The study analyzed the underlying health conditions in 5,700 patients, with a median age of 63, who were hospitalized in the New York City area between March 1 and April 4 with COVID-19. It included patients who survived, a key difference from the state fatalities-only figures.

The most common co-morbidities were hypertension (56.6%), obesity (41.7%) and diabetes (33.8%). Being older and being male were also common characteristics, researchers found, noting the "pattern" here is similar to data reported in China.

Hypertension's prevalence in both sets of New York data is worth noting. This is a common condition, affecting an estimated 29% of the general population, according to the U.S. Centers for Disease Control and Prevention. The percentage climbs steadily with age. The condition is also more prevalent among blacks.

So what is it about hypertension that may increase the risk of severe COVID-19 illness? And is the risk less if the condition is controlled with medication? "The short answer is we don't know,'' said Dr. Bradley Benson, the University of Minnesota Medical School's chief academic officer.

There are several theories involving vascular abnormalities or inflammation. While researchers scrutinize this, Benson is telling patients with hypertension to continue taking their medication and "not to hit the panic button."

"Most people with hypertension do just fine. But you do need to understand that if you get COVID … you do have a higher risk of a bad outcome. This is real."

Data-driven tools under development may soon help doctors more precisely calculate individuals' risk of a poor outcome after contracting COVID-19. Until then, Benson advises that patients with hypertension or other common conditions err on the side of caution, for example by continuing social distancing even as state-ordered precautions phase out.

Just because you can let down your guard against COVID doesn't mean you should.