Since the identification of the novel coronavirus and the characterization of the disease known as COVID-19, a substantial body of literature has emerged. Medical directors from across RGA's U.S. Mortality Markets have reviewed the latest research detailing the effect of age and chronic conditions on disease severity and mortality.
One of the earliest studies of the clinical features of novel coronavirus cases prospectively collected and analyzed the data on 41 patients in Wuhan, China with laboratory-confirmed infections. These patients were admitted from December 16, 2019 to January 2, 2020, and the median age of these patients was 49 years. Associated underlying disease included diabetes (20%), hypertension (15%), and cardiovascular disease (15%).
As the virus continued to spread, it became more evident that the elderly and those with underlying comorbidities were more likely to develop critical illness and experience a higher fatality rate. A recent meta-analysis revealed that the proportion of underlying diseases were significantly higher in critically ill and fatal cases compared to non-critically ill patients; in particular, having diabetes (odds ratio or OR 3.68), hypertension (OR 2.72), cardiovascular disease (OR 5.19) and respiratory disease (OR 5.15) put patients at high risk for severe disease and mortality.
Patients with cancer – particularly those with hematologic, lung, and metastatic malignancies – have also been found to be at significant risk of severe outcomes from coronavirus disease, with higher observed death rates (OR 2.34) and higher rates of intensive care unit (ICU) admission (OR 2.84). The odds ratio (OR) is a measure of the association of an exposure to an outcome; for example, an odds ratio of 2 doubles the odds of an outcome if there is a particular exposure.
In the U.S., the Centers for Disease Control has published the Morbidity and Mortality Weekly Report
, which includes the characteristics of patients whose COVID-19 infection was lab-confirmed in March 2020. It is evident from this report that comorbidities play an important role in disease severity, since 89.3% of hospitalized patients have underlying disease. Read the full introduction with references >
Read more about comorbidities and this evolving disease below.
Pulmonary Considerations in COVID-19
Severe acute respiratory syndrome coronavirus 2 is aptly named, says Dr. Preeti Dalawari, M.D., MSPH and Medical Director, RGA U.S. Mortality Markets
. Those with preexisting lung conditions are at an increased risk from SARS-CoV-2 or COVID-19. She reviews the latest available research on COVID-19-related pulmonary symptoms, including acute respiratory distress syndrome (ARDS), and shares a cogent analysis of complications and underwriting considerations. Read more >
COVID-19 and the Heart
With or without pre-existing conditions, COVID-19 has effects on the cardiovascular system, says Valerie Kaufman, M.D., FACC, DBIM, Vice President and Medical Director. RGA U.S. Mortality Markets
. She identifies underlying cardiovascular disease types associated with higher risk, explores complications such as Acute COVID-19 Cardiovascular Syndrome (ACovCS), and advises about strong predictors of adverse outcomes. The pathophysiology of cardiac injury from COVID-19 is complex and not completely understood, but researchers are gaining greater clarity. Read more >
COVID-19, Obesity and Diabetes
Clinicians have observed a complex interplay, much of which is still unclear, between SARS-CoV-2, obesity, and its associated conditions such as diabetes and pulmonary disease, says Maryam Shapland, M.D., DBIM, Vice President and Medical Director, RGA U.S. Mortality Markets
. She reviews the current research regarding the effect of obesity on the severity of disease, the influence of age, the role of diabetes, and the extent to which obesity is an independent risk factor or confounding variable. Read more >
Impact on the Older Age Population
(Defined as over the age of 65)
Why has COVID-19 hit the elderly so hard? Mortality related to COVID-19 is clearly impacted by comorbidities, which are more common at older ages, says Lisa Duckett, M.D., DBIM, Vice President and Medical Director, RGA U.S. Mortality Markets
. Still, several other factors predispose the elderly to worse outcomes. She discusses atypical symptoms and comorbidities that further elevate risk. Read more >
Neurologic Complications of COVID-19
Neurologic symptoms are very common in COVID-19, especially early in the disease, says Dave Rengachary, M.D., DBIM, FALU, FLMI, Senior Vice President and Chief Medical Director, RGA U.S. Mortality Markets
. The greatest mortality concern relates to stroke, but at least mild cognitive impairment is quite common after prolonged intensive care hospitalization. He reviews nervous system symptoms and complications. Read more >