Delivery Hospitalization Cardiac and Respiratory Complications during SARS-CoV-2 Delta Variant Dominance

Abstract

In 2021, the severe acute respiratory syndrome coronavirus 2 Delta variant rapidly proliferated and became dominant. Some but not all research evidence supports that Delta was associated with increased maternal risk. The purpose of this study was to determine whether Delta was associated with risk for cardiac and respiratory complications in a national sample. Of an estimated 3,495,188 delivery hospitalizations in 2021, 1.8% of pre-Delta deliveries (n = 29,580; January–June) and 2.1% of Delta-period deliveries (n = 37,545; July–December) had a coronavirus disease 2019 (COVID-19) diagnosis. The Delta period was associated with increased adjusted odds of respiratory complications (adjusted odds ratio [aOR] = 1.54, 95% CI: 1.41, 1.69) and cardiac severe maternal morbidity (SMM; aOR = 1.54, 95% CI: 1.40, 1.69). Among deliveries with a COVID-19 diagnosis, the Delta period was associated with a higher incidence of respiratory complications (8.4 vs. 3.7%) and cardiac SMM (8.4 vs. 3.5%; p < 0.01 for both). These findings corroborate prior clinical studies suggesting that the Delta strain was associated with an increased maternal population-level clinical burden.

Key Points

• The Delta strain was associated with an increased maternal population-level clinical burden.

• The Delta period was associated with an increased risk for cardiac and respiratory complications.

• Among deliveries with a COVID-19 diagnosis, the Delta period was associated with increased risk.

Keywords

COVID-19 - Delta variant - maternal outcomes - pregnancy - morbidity

Institutional Review Board Approval

Given that this study involved a de-identified and publicly available dataset, the Institutional Review Board review by both Columbia University and the University of California, San Francisco, deemed this exempt from review.

Publication History

Received: 25 June 2024

Accepted: 30 August 2024

Accepted Manuscript online:
02 September 2024

Article published online:
30 September 2024

• References

• 1 Metz TD, Clifton RG, Hughes BL. et al; National Institute of Child Health and Human Development Maternal-Fetal Medicine Units (MFMU) Network. Association of SARS-CoV-2 infection with serious maternal morbidity and mortality from obstetric complications. JAMA 2022; 327 (08) 748-759
• 2 Allotey J, Stallings E, Bonet M. et al; for PregCOV-19 Living Systematic Review Consortium. Clinical manifestations, risk factors, and maternal and perinatal outcomes of coronavirus disease 2019 in pregnancy: living systematic review and meta-analysis. BMJ 2020; 370: m3320
• 3 Wen T, Logue TC, Wright JD, D'Alton M, Booker WA, Friedman AM. Adverse delivery hospitalisation outcomes in 2020 during the COVID-19 pandemic. BJOG 2024; 131 (08) 1111-1119
• 4 Atherstone CJ, Guagliardo SAJ, Hawksworth A. et al. COVID-19 Epidemiology during Delta variant dominance period in 45 high-income countries, 2020-2021. Emerg Infect Dis 2023; 29 (09) 1757-1764
• 5 Del Rio C, Malani PN, Omer SB. Confronting the Delta variant of SARS-CoV-2, Summer 2021. JAMA 2021; 326 (11) 1001-1002
• 6 Samieefar N, Rashedi R, Akhlaghdoust M, Mashhadi M, Darzi P, Rezaei N. Delta variant: the new challenge of COVID-19 pandemic, an overview of epidemiological, clinical, and immune characteristics. Acta Biomed 2022; 93 (01) e2022179
• 7 Sheikh A, McMenamin J, Taylor B, Robertson C. Public Health Scotland and the EAVE II Collaborators. SARS-CoV-2 Delta VOC in Scotland: demographics, risk of hospital admission, and vaccine effectiveness. Lancet 2021; 397 (10293): 2461-2462
• 8 Wang AM, Berry M, Moutos CP. et al. Association of the Delta (B.1.617.2) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with pregnancy outcomes. Obstet Gynecol 2021; 138 (06) 838-841
• 9 Adhikari EH, MacDonald L, SoRelle JA, Morse J, Pruszynski J, Spong CY. COVID-19 cases and disease severity in pregnancy and neonatal positivity associated with Delta (B.1.617.2) and Omicron (B.1.1.529) variant predominance. JAMA 2022; 327 (15) 1500-1502
• 10 The Healthcare Cost and Utilization Project. Introduction to the HCUP National Inpatient Sample (NIS). 2021 . Accessed April 15, 2024 at: https://hcup-us.ahrq.gov/db/nation/nis/NIS_Introduction_2021.jsp
• 11 Healthcare Cost and Utilization Project. Overview of the National (Nationwide) Inpatient Sample. Accessed May 1, 2023 at: https://www.hcup-us.ahrq.gov/nisoverview.jsp
• 12 Healthcare Cost and Utilization Project. Trend Weights for HCUP NIS Data. Accessed May 1, 2023 at: https://www.hcup-us.ahrq.gov/db/nation/nis/trendwghts.jsp
• 13 Clapp MA, James KE, Friedman AM. Identification of delivery encounters using International Classification of Diseases, Tenth Revision, diagnosis and procedure codes. Obstet Gynecol 2020; 136 (04) 765-767
• 14 Lynch KE, Viernes B, Gatsby E. et al. Positive predictive value of COVID-19 ICD-10 diagnosis codes across calendar time and clinical setting. Clin Epidemiol 2021; 13: 1011-1018
• 15 Lambrou AS, Shirk P, Steele MK. et al; Strain Surveillance and Emerging Variants Bioinformatic Working Group, Strain Surveillance and Emerging Variants NS3 Working Group. Genomic Surveillance for SARS-CoV-2 Variants: Predominance of the Delta (B.1.617.2) and Omicron (B.1.1.529) Variants - United States, June 2021-January 2022. MMWR Morb Mortal Wkly Rep 2022; 71 (06) 206-211
• 16 Eid J, Abdelwahab M, Caplan M. et al. Increasing oxygen requirements and disease severity in pregnant individuals with the SARS-CoV-2 Delta variant. Am J Obstet Gynecol MFM 2022; 4 (03) 100612
• 17 Adhikari EH, SoRelle JA, McIntire DD, Spong CY. Increasing severity of COVID-19 in pregnancy with Delta (B.1.617.2) variant surge. Am J Obstet Gynecol 2022; 226 (01) 149-151