# Positive Trends in COVID-19 In-Hospital Mortality Rates
Written on
Chapter 1: Overview of COVID-19 Mortality Trends
At the onset of the pandemic, COVID-19 was notorious for its high mortality rates, particularly among older adults and those with preexisting health conditions who had weakened immune systems. Fast forward to today, how dangerous is COVID-19?
Recent data indicates a notable decline in mortality rates among hospitalized patients and the general population. This decrease is primarily attributed to enhanced testing capabilities that have identified a greater number of mild cases, especially in younger demographics. However, the improvement in outcomes for those who require hospitalization is particularly noteworthy.
Section 1.1: Evidence of Reduced In-Hospital Death Rates
Dr. Leora I. Horwitz, an associate professor and director of a research center at the New York University Grossman School of Medicine, along with her colleagues, recently published a study titled "Trends in COVID-19 Risk-Adjusted Mortality Rates in a Single Health System" in the Journal of Hospital Medicine. This research examined over 5,000 hospitalization records in New York City from March to August, calculating the monthly in-hospital mortality rates.
According to their findings, "Adjusted mortality dropped each month, from 25.6% in March to 7.6% in August." The term "adjusted" refers to controlling for factors such as age, sex, race, body mass index, smoking history, and comorbidities like hypertension, diabetes, and heart disease, ensuring that the outcomes are not skewed by these variables.
While the unadjusted mortality rates exhibited an even steeper decline, indicating that confounding factors only partially accounted for the drop, the study acknowledges limitations, such as its focus on a single geographic area—New York—and the possibility of overlooked confounding variables.
Section 1.2: Ongoing Risks and Long-Term Effects
Despite the encouraging trends, Dr. Horwitz cautioned that COVID-19 mortality rates remain elevated compared to other infectious diseases, including influenza. She emphasized that the pandemic's long-term effects, especially for the one in ten patients who become long-haulers, underscore the seriousness of the virus. "I do think this is good news, but it does not make the coronavirus a benign illness," she remarked.
Chapter 2: Insights from Other Studies
A recent preprint study (not yet peer-reviewed) focusing on data from 14,958 COVID-19 patients in England, conducted from March to June, also reported a gradual decline in mortality rates. The authors noted that "as a linear trend from the first week of April, adjusted mortality risk decreased by 11.2% per week in the High Dependency Unit (HDU) and 9.0% in the Intensive Care Unit (ICU)."
Overall, evidence from both New York and England shows a decrease in COVID-19 in-hospital mortality rates that is not solely attributable to younger age or fewer comorbidities.
Section 2.1: Factors Contributing to Improved Outcomes
Enhanced Clinical Practices
The medical community has greatly expanded its knowledge about COVID-19, with over 60,000 research papers published to date. A significant breakthrough has been the use of the inexpensive corticosteroid dexamethasone, which has proven effective in reducing mortality among patients on ventilators and supplemental oxygen.
Dexamethasone effectively mitigates two phases of inflammation, unlike nonsteroidal anti-inflammatory drugs (NSAIDs) that only address one phase. Improved communication regarding treatment protocols, especially concerning ventilator use and patient management, has also contributed to better outcomes.
"None of our hospitals were flooded," stated Dr. Monica Gandhi, a professor of medicine at the University of California. "You have enough nurses. You're only doing your job, not other people's jobs."
Reduced Viral Load Exposure
Another explanation for the decline in mortality rates is the observed decrease in viral load, attributed to increased mask-wearing and adherence to social distancing measures. Masks help reduce the viral dose inhaled, leading to a higher number of asymptomatic and less severe cases than earlier in the pandemic.
Potential Changes in Viral Strains?
Initially, there was speculation about whether earlier strains of the virus were more virulent. However, recent studies comparing the current dominant strain (G614) with previous strains have not indicated any significant differences in mortality rates.
In summary, while COVID-19 mortality rates in both the general population and hospitalized patients have shown a downward trend, this improvement is largely due to enhanced clinical practices and public health interventions, rather than a less virulent strain of the virus. It is crucial to recognize that COVID-19 remains a serious illness, even as we see positive developments in management and outcomes.