Patients With TTP, COVID-19 Had Higher Mortality, More Complications

Patients who had concurrent thrombotic thrombocytopenic purpura (TTP) and COVID-19 had a heightened mortality and increased incidence of complications, according to a study published in Clinical and Applied Thrombosis/Hemostasis.

TTP is a disease that threatens the life of those who contract it, with symptoms including hemolytic anemia, renal failure, fever, and neurological symptoms. Decreases in ADAMTS-13 is the primary cause of TTP, due to a virus-induced immune response. Some patients with COVID-19 have reported that a complication of the virus was the development of TTP. This retrospective study aimed to evaluate the effect of TTP on COVID-19 outcomes in adults aged 18 years and older who had COVID-19.

Patient coughing | Image credit: Graphicroyalty - stock.adobe.com

The National Inpatient Sample database was used to collect data for the study, which is a database that includes 98% of the population from 48 states in the United States. Clinical codes for diagnoses, gender, age, race, median household income, and length of stay were included in the data.

Patients aged 18 years and older who were admitted with a primary diagnosis of COVID-19 were included in this study, with patients who had concurrent TTP identified using diagnosis codes to find those who had a secondary diagnosis of TTP and who received plasma exchange and/or caplacizumab.

All-cause inpatient mortality, acute myocardial infarction (AMI), acute cerebrovascular accident (CVA), acute kidney injury (AKI), gastrointestinal bleeding (GIB), intensive care unit (ICU) admission, AKI requiring dialysis, blood transfusion, and lower extremity or pulmonary vessel venous thromboembolism (LE DVT/PE) were all outcomes assessed by the researchers. Total hospitalization charges and length of stay were also compared between patients with TTP vs without TTP who also had COVID-19.

There were 1,050,045 adults in the database who were hospitalized for COVID-19, with only 0.03% who also had TTP. Patients who had COVID-19 complicated by TTP were younger than those without TTP (mean age, 57.47 vs 64.74 years). Preexisting conditions were more common in patients with TTP compared with those without, including congestive heart failure (16.82% vs 13.33%) and end-stage renal disease (3.69% vs 3.33%). Teaching hospitals more often received patients with TTP (90% vs 68.95%) compared with those without TTP.

There was an elevated mortality rate in patients with TTP compared with those without (adjusted OR [aOR], 3.99; 95% CI, 1.93-8.28).

The study also found the following were more frequent in patients with TTP:

• LE DVT/PE (aOR, 3.33; 95% CI, 1.40-7.91)
• AKI (aOR, 7.36; 95% CI, 3.74-14.50)
• AKI that needed dialysis (aOR, 23.78; 95% CI, 12.31-45.94)
• GIB (aOR, 10.75; 95% CI, 4.77-24.23)
• Blood transfusions (aOR, 20.32; 95% CI, 12.19-42.33)
• ICU admission (aOR, 14.42; 95% CI, 8.52-24.43)

Length of stay (adjusted mean difference, 17.42 days; 95% CI, 12.73-22.10) and total hospitalization charges (adjusted mean difference, $298,476; 95% CI, 195,883-401,069) were higher in patients with TTP who had COVID-19.

There were some limitations to this study. Cases could not be fully randomized due to the retrospective design of the study. Coding inaccuracies were possible in the database due to it being claims-based. There is a possibility that residual confounders remain. The misclassification of a diagnosis is also possible.

The researchers concluded that there was an association between TTP and a higher risk of mortality as well as increased risk and incidence of complications in patients with both TTP and COVID-19. Managing both TTP and COVID-19 should be studied in future research.

Reference

Jaan A, Sarfraz Z, Khalid F, Anwar J. Impact of concomitant thrombotic thrombocytopenic purpura on COVID-19 mortality and morbidity: a nationwide inpatient sample analysis. Clin Appl Thromb Hemost. 2023;29:1-6. doi:10.1177/10760296231219252