Abstract
Background:
Monkeypox (Mpox) is a reemerging, neglected viral disease. By May 2023, worldwide Mpox cases surpassed 87,000. Predictive factors for hospitalization with Mpox are lacking.
Objective:
We aim to compare clinical characteristics and outcomes in hospitalized and nonhospitalized patients with Mpox infection.
Design:
A multicenter retrospective case-control cohort of patients with Mpox infection.
Methods:
We performed a propensity score match analysis from a global health network (TrinetX). We compare clinical characteristics and outcomes between hospitalized and nonhospitalized patients with Mpox.
Results:
Of 1477 patients, 6% were hospitalized, 52% required an ED visit, and 29% received treatment at urgent care. After propensity score matching, 80 patients remained in each group. Hospitalizations were more common among Black persons (51% versus 33%, p = 0.01), people with HIV (50% versus 20%, p < 0.0001), and those with proctitis (44% versus 12.5%, p < 0.001).
Conclusion:
Independent predictive factors of hospitalization in our cohort for Mpox included people who are Black with a diagnosis of HIV, severe proctitis, pain requiring opioids, and elevated lactate dehydrogenase. Greater recognition of factors associated with increased risk of Mpox severity and hospitalization is paramount.
Background
Mpox is a reemerging, neglected viral infection that previously affected African countries over the last 50 years. By May 2023, worldwide Mpox cases surpassed 87,000. In the current outbreak, complications like proctitis, tonsillitis, and skin and soft tissue infections have been reported.1,2 Mpox infection was associated with increased severity and occasional death in some vulnerable populations, particularly those with advanced human immunodeficiency virus (HIV) infection. 3 We also have a scarcity of drugs available to manage the disease. 4 Immunocompromising conditions are common among hospitalized patients with Mpox, with up to 80% of cases being in people with HIV. 5 However, we lack additional predictive risk factors associated with Mpox severity and hospitalization. Using a global health network, we compared clinical characteristics and outcomes in hospitalized and nonhospitalized patients with Mpox infection.
Methods
Patients ⩾18 years of age with Mpox were identified from TriNetX, a global federated research network, on February 24, 2023. We used the International Classification of Diseases and laboratory results to define the Mpox diagnosis (Supplementary Material). The patient population was divided into two cohorts based on the requirement for hospitalization within 1 month after the initial Mpox diagnosis since complications requiring admission are more commonly present within this timeframe. The primary outcome was to compare clinical features by hospitalization status within 1 month after Mpox diagnosis. Medication use, laboratory values, healthcare utilization, and death were compared between groups.
Statistical analyses were completed using the TriNetX platform. Continuous data were compared using independent t-tests, whereas categorical data were compared using χ2 or Fisher’s exact test. Outcomes were assessed by propensity score matching. Research utilizing TriNetX does not require ethical approval because patient-identifiable information is not accessible to users.
Results
We identified 1477 patients with Mpox, of which 52% required an emergency department (ED) visit, 29% received treatment at urgent care, and 6% were hospitalized. Among those hospitalized, <1% required ICU care, and no deaths were reported. The hospitalized group was more likely to be White or Black persons (Table 1). Patients requiring hospitalization reported more systemic symptoms and had higher proportions of immunocompromising conditions and HIV. More than half of admitted patients reported rash and a quarter fever, significantly higher than in non-admitted patients. Close to 60% of admitted patients had HIV compared to 31% of non-admitted patients. Syphilis, aplastic anemia, and diabetes mellitus, type 2 (DM2) were more commonly present in hospitalized patients. Overall, proctitis and cellulitis were the most common Mpox complications. While Mpox complications were infrequently recorded, they were significantly more common among hospitalized patients.
Clinical characteristics of Mpox patients by hospitalization status.
In TriNetX, patient counts ⩽10 are rounded to 10, so the exact number is obfuscated for privacy purposes. DM2, Diabetes Mellitus, type 2
Capture of comorbidities was not time bounded. Other variables were captured within 3 months before the Mpox diagnosis.
Laboratory tests were not performed for all patients, which likely reflected differences in institutional and clinical practices.
Immunosuppressants included: Tacrolimus, Mycophenolate mofetil, Mycophenolic acid, Cyclosporine, Azathioprine, Sirolimus, Infliximab, Basiliximab, Belatacept, Omalizumab, Siltuximab, Belumosudil, and Ustekinumab.
Use of the medication within a month after Mpox infection.
CD4 counts were significantly lower, and HIV ribonucleic acid (RNA) viral loads were significantly higher among patients requiring hospitalization. Prior use of opioids, immunosuppressants, and glucocorticoids was greater in those admitted. Tecovirimat and a previous smallpox vaccine were uncommon in both groups.
After propensity score matching, 80 patients remained in each group. Hospitalized patients were more likely to be Black persons (51% versus 33% p = 0.01). Furthermore, patients requiring admission had a higher prevalence of HIV (50% versus 20% p < 0.0001) and proctitis (31% versus 12.5%, p = 0.004) with higher lactate dehydrogenase (LDH; 344 ± 126 versus 221 ± 0, p = 0.006) and increased use of opioids for pain management (44% versus 12.5%, p < 0.001).
Discussion
We found a 6% hospitalization rate within 1 month after Mpox diagnosis, in which systemic symptoms and complications associated with Mpox were more common among those admitted. Hospitalized patients with Mpox were disproportionally young Black men with high rates of HIV infection or other immunosuppressive conditions. The reported overall hospitalization rate for paients with Mpox is 14%; 6 Higher for those with HIV (8% versus 3%). Additionally, patients with HIV are more likely to be symptomatic or present to the ED. 7 In addition to advanced HIV, 3 a history of organ transplantation and hematological malignancy are common among those hospitalized, 5 as seen in our study. We also observed higher HIV viral loads and lower CD4 counts in those admitted suggesting poor virologic control. People with HIV had more severe Mpox infections and presented with widespread, significant, necrotizing lesions and mucosal involvement. 3
Mpox severity and hospitalization have disproportionately affected persons from minority ethnicities, mainly Black or African American, or Hispanic persons. We need to emphasize the importance of early disease recognition and increase the availability of Mpox vaccination, access to antiretroviral therapy, and linkage to care to close the racial disparity gap. In a report from Georgia, despite Black persons making up to 79% of Mpox infections, only 45% have received the first dose of the Jyneos vaccine. 8 Additionally, Black persons are less likely to receive tecovirimat than White or Hispanic persons based on data from CDC.
Independent predictive factors of hospitalization in our cohort for Mpox included people who are Black, a diagnosis of HIV, severe proctitis, pain requiring opioids, and elevated LDH.
Our study has some limitations. The retrospective nature of the follow-up cohort may introduce selection bias. Isolating the effect of hospitalization is complex and multifactorial, and selected available data may confound differences.
Conclusions
People with HIV, particularly those with poorly controlled HIV and Black persons are at increased risk of Mpox severity and hospitalization. Additional immunosuppressive conditions such as hematological malignancy and neoplasm may also play a role. Possible contributing causes for admission are increased tissue injury, proctitis, and pain. Increased awareness and vaccination of those populations at risk are paramount.
Supplemental Material
sj-docx-1-tai-10.1177_20499361231196683 – Supplemental material for Hospitalization risk among patients with Mpox infection—a propensity score matched analysis
Supplemental material, sj-docx-1-tai-10.1177_20499361231196683 for Hospitalization risk among patients with Mpox infection—a propensity score matched analysis by Andrés F. Henao-Martínez, Chloe M. Orkin, Boghuma K. Titanji, Alfonso J. Rodriguez-Morales, Jorge L. Salinas, Carlos Franco-Paredes, Jose Tuells and Daniel B. Chastain in Therapeutic Advances in Infectious Disease
Footnotes
References
Supplementary Material
Please find the following supplemental material available below.
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