Latino Patients With Rheumatic Diseases are at Higher Risk of Contracting COVID-19

February 1, 2021
Lana Dykes

The primary objective of this retrospective study was to understand why Latino patients were being disproportionately affected by COVID-19. Of the patients observed, 32 (18%) developed COVID-19 during the study period, meaning incidence rates were 5- to 11-fold higher than the general population (1,540 to 3,431/100,000).

A recent study, published in Arthritis and Rheumatology,1 discovered that Latino patients had a greater chance of being exposed to and contracting coronavirus disease 2019 (COVID-19) when compared with the rest of the population due to higher rates of obesity and sociodemographic factors. Further, Latino patients with rheumatic diseases are at an even greater disadvantage as viral infections, like COVID-19, have been shown to trigger rheumatic disease flares.

The primary objective of this retrospective study was to understand why Latino patients were being disproportionately affected by COVID-19. It gleaned its information from an existing cohort of 307 participants with rheumatic diseases being reviewed as a board-approved natural history study in the Intramural Research Program at the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS). Of these, investigators focused on 178 Latino patients in the Washington, DC, area, analyzed between April 1 and October 15, 2020. Variables like demographics, body mass index (BMI), comorbidities, rheumatic disease type, disease flare, and immunomodulatory therapies were recorded. In order to help identify risk factors and rheumatic disease flare, investigators used both Classification and Regression Tree (CART) and logistic regression (LR) analyses.

Previously established risk factors include age (greater than 65 years), obesity, hypertension, diabetes mellitus, and lung disease. Latinos living in the United States not only have a higher prevalence of these conditions, but they also have lower rates of insurance coverage in comparison with the general population.

Of the patients observed, 32 (18%) developed COVID-19 during the study period, which is 3 times higher than the general Latino population (17,978/100,000 versus 4689 to 5809/100,000, respectively). Incidence rates were 5- to 11-fold higher than the general population (1,540 to 3,431/100,000). The incidence rate for Latino residents was calculated using the local health department case counts and census data. Latino patients who were asymptomatic were selected as a comparator group (n = 146). A total of 78% (25/32) of these patients were uninsured.

Investigators reported symptoms, management, and any hospitalizations for the positive patients. Eight experienced disease flares that coincided with their positive results. Two were previously in remission, 2 had their therapy withheld, and the remaining 4 continued with their usual treatment plan. Both CART and LR analyses confirmed COVID-19 as a risk factor for rheumatic disease flares.

None of the COVID-19-positive patients required intensive care unit (ICU) care, with 81% able to manage their illness with outpatient treatment. Six patients were hospitalized, with 2 needing supplemental oxygen (they have since recovered). “Previously published studies suggest that Latino patients are more likely to develop severe COVID-19 infection and have a worse outcome. None of the patients with COVID-19 required mechanical ventilation or had a poor outcome, although 2 did meet criteria for severe disease,” investigators explained. “Possible explanations for milder disease in our patient population could include younger age, majority female, relatively mild pre-existing conditions, limited pre-infection GC exposure, and perhaps mitigating effects of existing immunomodulatory therapy.”

In the positive cohort, 91% were female, with a mean age of 46 years, and had similar demographics to the COVID-19 negative group. The mean BMI of the COVID-19 patients was comparatively higher (32.5 versus 29.7, respectively). Among the positive patients, 62.5% were obese. Both CART and LR analyses indicated that patients with a BMI>30.35 were at greater risk for contracting COVID-19 [P=0.004, OR=3.37, 95%CI (1.5-7.7)]. A positive result also increased the chances of rheumatic disease flare [P=0.02, OR=4.57, 95%CI (1.2-17.4)]. “We identified obesity and increasing age as risk factors for COVID-19. The presence of COVID-19 along with interruptions in immunomodulatory therapy were found to be risk factors for rheumatic disease flares. None of the specific immunomodulatory therapies increased risk for COVID-19,” said investigators.

In addition to obesity, sociodemographic status was also an added risk factor for the Latino population. “Patients in our cohort and their family members represent essential and frontline workers and thus already were at an increased risk of exposure to COVID-19. Thus, sociodemographic factors likely contributed greatly to the increased incidence of COVID-19 in our cohort,” investigators theorized. “Latinos are more likely to work in positions considered to be essential, thus increasing their risk for exposure to infections. Such jobs often provide limited or no sick time, further perpetuating this increased risk to Latino workers. The combination of these factors has led to Latino patients being disproportionately impacted by COVID-19, resulting in increased incidence, severity of disease, and mortality.”

“An interesting finding from our study was the identification of BMI>30.35 as a risk factor for COVID-19 infection. BMI>30 is the definition of obesity and the finding of BMI>30.35 by CART analysis is notable. Obesity has been documented as a risk factor for severe COVID-19, requiring hospitalization, but its role in increased susceptibility to infection has not been evaluated. Obesity affects metabolic and immune functioning leading to increased COVID-19 risk,” investigators rationalized. “Another important observation was the risk from COVID-19 in increasing disease flares in rheumatic disease patients. This risk from COVID-19 was independent of interruptions in immunomodulatory treatments. Rheumatologists should follow patients reporting COVID-19 closely during the post-infection period in anticipation of a potential rheumatic disease flare.”

The study was limited by its retrospective, single-site nature, coupled with the fact that essential workers are inherently at a greater risk of exposure to COVID-19. To counteract the lack of generalizability, “future studies including marginalized populations, with larger sample sizes from different geographic locations, including younger patients, and with longer follow-up periods are warranted to confirm these findings,” the research team concluded.

Reference:

Fike A, Hartman J, Redmond C, et al. Risk factors for COVID-19 and rheumatic disease flare in a US cohort of Latino patients [published online ahead of print, 2021 Jan 17]. Arthritis Rheumatol. 2021;10.1002/art.41656. doi:10.1002/art.41656