Prevalence of renal dysfunction in COVID-19 patients.pdf

This study at Jackson Park Hospital examines the long-term renal effects of COVID-19, with 28% of hospitalizations involving acute kidney injury and 9% requiring renal replacement therapy. It highlights the need for more research on the pandemic's impact on African American communities, which face higher rates of cases and deaths.

1. Prevalence of renal dysfunction in COVID-19 patients: A retrospective
cohort study in a Chicago south side community hospital
FARAZ KHAN, D.O., LAKSHMI DODDA, M.D.
FAMILY MEDICINE, JACKSON PARK HOSPITAL
FARAZ KHAN, D.O., LAKSHMI DODDA, M.D., SYED MOHAMMAD ARISH AYUB M.D., AREEBA MARRIUM M.D.,
EZRA EFOME KWAME M.D.
FAMILY MEDICINE, JACKSON PARK HOSPITAL

2. Introduction
Since the beginning of the pandemic, over 79 million confirmed cases and over 900 thousand
deaths in the US alone.
1
This study was undertaken at Jackson Park hospital to evaluate the long-term consequence of
COVID-19, specifically with regards to worsening renal dysfunction. Approximately 28% of
COVID-19 hospitalizations are diagnosed with AKI and 9% receive renal replacement therapy.
2
Studies on the long-term impact in African American communities are lacking, with research
pointing towards disproportionately higher incidences of COVID-19 cases, deaths, and case
mortality.
3

3. Methods -Study Design
-A retrospective cohort study was designed to evaluate 324 COVID positive patients starting
from August 2020 until November 2021. Patients that passed away, had no baseline renal
function tests or had no follow-up labs were excluded. The research was approved by the JPH
IRB committee and ethics committee.
-COVID severity defined as:
◦Group 1, no oxygen requirement
◦Group 2, oxygen requirement limited to high flow nasal cannula/nasal cannula and
◦Group 3, use of noninvasive ventilation such as Bipap/CPAP or use of mechanical ventilation.
-Clinical data collected: COVID positive results, eGFR during follow-up, eGFR hospitalization,
comorbidities (such as diabetes and hypertension). COVID positive results are based on RT-PCR.
As for the hospitalization eGFR, the best eGFR for that hospitalization was utilized. F/u eGFR was
based on latest renal function test performed when patient followed up at JPH
.

4. Methods -Study Design
-The primary outcome was decline in eGFR which was defined as an eGFR < 90 as was used by
Huang et al. 2021. In this study, acute kidney injury (AKI) was identified and classified based on
KDIGO guidelines, specifically as the rise of serum creatinine to 1.5 times the baseline
creatinine. Baseline creatinine was defined as the lowest serum creatinine during the acute
phase hospitalization for COVID.

5. Statistical Analysis
-Univariate odds ratios were calculated between Group 2 and Group 1 as well as Group 3 and
Group 1.
-Multivariable adjusted logistic regression analysis was performed to evaluate renal dysfunction
based on COVID severity levels and were adjusted according to risk factors (smoking,
hypertension, diabetes, dialysis, ACE-I/ ARB use). Confidence intervals and p-values were also
calculated.
◦Due to limited sample size, for logistical regression analysis Groups 2 and 3 were combined for the
analysis. Therefore, odds ratios were calculated between patients with COVID requiring oxygen
compared to those not requiring oxygen.
-Statistical analysis completed viaSTATA.

6. Data –
Demographics
Total
Age, years 60.5 (53-74)Sex
Men 23/46
Women 23/46
Tobacco use 15/46
Alcohol Use 11/46
Comorbidities
Hypertension 28/46
Diabetes 20/46
Stroke 4/46
Chronic kidney disease 10/46
Illicit drug use (Cocaine, heroin, marijuana) 7/46
Hyperlipidemia 15/46
Dialysis 7/46
Medications
Ace-inhibitors/Angiotensin Receptor Blockers 11/46
O2 requirement
No oxygen supplementation 22/46
ModerateSupplementalO2 (Nasal cannula, HFNC) 20/46
Severe O2 (Mechanical ventilation
, Bipap/CPAP)
4/46

7. Results
-A total of 27 of 46 patients (58.7%) had decreased eGFR <90 mL/min on follow up. A total of 15
of 44 patients (34%) had acute kidney injury at acute phase.
-52.6% (10 of 19) patients that did not have renal dysfunction (i.e. eGFR <90) during the acute
phase of COVID had eGFR <90 on follow-up.

8. Results
2x2 tables
Non-AKI (Acute phase)
AKI (Acute phase)
non-AKI F/U eGFR <90F/U eGFR >90
egfr >90 (acute) +
non-AKI 10 9
egfr< 90 (Acute) +
non-AKI 9 2
AKI F/U eGFR <90F/U eGFR >90
egfr>90 (acute) + AKI 2 5
egfr< 90 (Acute) + AKI 6 3

9. Results
324 patients
COVID (+)
46 total
patients
non-AKI ( n=30)
eGFR >90 (n=
19)
eGFR<90 (N =
10)
eGFR >90 (n=9)
eGFR <90 (n=
11)
eGFR<90 (n=9)
eGFR >90 (N=2)
AKI (n=16)
eGFR >90 (n = 7)
eGFR<90 (n= 2)
eGFR >90 (n=5)
eGFR <90 (n= 9)
eGFR<90 (n= 6)
eGFR >90 (n=3)
278 excluded:1) death 2) no f/u
renal function data 3) no initial
enalfunction data
FOLLOW-
UP
ACUTE
PHASE

10. Results
Statistical Analysis
Univariate Odds Ratios without
multivariate adjustment
Group 2 vs. Group 1
&
Group 3 vs. Group 1
EGFR <90
follow-up
EGFR >90
followup
Exposure (O2
supplementation)
Supplemental O2 (2) 155
No O2 (1) 1012
Odds Ratio 3.6
Confidence Interval (0.945- 13.41)
EGFR <90
follow-up +
No O2
EGFR >90
followup+
No O2
Exposure (O2
supplementation)
Mechanical vent O2 (3) 22
No O2 (1) 10 12
Odds ratio 1.2
Confidence Interval (0.142-10.12)
Group 3 vs. Group 1
Group 2 vs. Group 1

11. Results
Statistical Analysis
COVID severity Group 2 vs.
Group 1
&
COVID severity Group 3 vs.
Group 1

12. Results
Statistical Analysis
COVID severity Group 2 + 3 vs. Group 1

13. Discussion
Thisstudy showed that having severe COVID with any level of oxygen
supplementation showed renal dysfunction during follow-up after
multivariate adjustment (OR: 8.06, p<0.03, CI 1.23 –52.91). This
study corroborates what was found in the original Wuhan study.
◦Increasing the sample size may help to tighten the confidence
interval.

14. Discussion
Compared to Wuhan study, our study found a higher proportion of
individuals without renal dysfunction in hospitalization with development
of renal dysfunction during follow-up (52.6% vs. 13%). Many factors
played a role that can explain the increased effect:
◦The sample size was larger in the Wuhan study (1733 vs. 46).
◦There are also many socioeconomic barriers to care in the JPH community as well as
higher prevalence of hypertension (60% vs. 29%) and diabetes (44% vs. 12%). Further
data collection will clarify the true prevalence of renal dysfunction after COVID-19.
◦Follow-up renal function data ranged from 2 months to 14 months. Earlier follow-ups
may have been more likely to be associated with renal dysfunction compared to later
follow-ups.

15. Discussion
Ace-inhibitor use in our study was found to be possibly not
protective (OR 2.99, CI (.36 –24.7)).
◦Preclinical research in COVID-19, showed that reduced Ace-I expression in
alveolar cells leads to rapid progression to ARDS, suggesting Ace-inhibitors
may not be protective. However, small empiric studies have shown improved
survival in COVID patients.
3
◦With more data collection the relationship may reverse. Pre-hospital
medication vs. in-hospital medication initiation was also difficult to
differentiate in EMR and could have affected the results, since these are likely
two different populations.

16. Discussion
Limitations
Selection bias
◦Many individuals with renal dysfunction also passed away from COVID during hospitalization,
especially those on ventilators (Group 3)so this study may underestimate the true risk of renal
dysfunction.
◦Majority of patients that tested positive were a hospital-based population with some outpatient.
Inpatients are on average sicker than outpatients. Further research is needed to evaluate long
term outcomes between inpatient and outpatients.

17. Discussion
Limitations (continued)
•Due to retrospective nature of our study, not all parameters were available in
every patient and andimproper coding could have affected the results (e.g. or
not coding a disease such as Hypertension/diabetes, erroneous medication
reconciliation, etc.)
•Serum creatinine is limited as a proxy for renal dysfunction, which might result
in underestimation of patients with acute kidney injury in the acute phase.
5,6
•Follow-up eGFR: Variable time frame ranging from 2 months to 14 months.
Renal function can take over a year to stabilize and with COVID it is unknown
how renal recovery will look.
7
The Wuhan study was ambi-directional, so all
follow-ups and renal function tests were performed at 6-month time frame.

18. Discussion
•
Future directions
•A prospective study that follows COVD-19 survivors and observing whether there is renal
recovery or not.
•COVID vaccination rates have been increasing and should be evaluated as a covariate moving
forward.
•Consider Cox regression analysis to account for time to renal dysfunction.
•Consider combining data collection with other local hospital systems to increase sample size.

19. Impact as Primary Care Physician
•Given the evolving COVID 19-crisis, this study underscores the importance of longitudinal
studies to evaluate long term effects of COVID-19 on renal function and other organ systems is
imperative.
•The study also supports that those who required oxygen supplementation and thus more severe
disease must be closely monitored for renal recovery underscoring importance of post-discharge
care.
•Family Medicine physicians are in a unique position to tackle this important challenge.
•Results of this study as of now suggest that Ace-I/ARB did not appear protective, however more
data is needed and if true may inform our decision to explore other agents (e.g. SGLT-2, etc.)

20. Acknowledgements
Special thanks to our medical students for data collection: AreebaMarrium, Syed Mohammed
Arish Ayub, and Ezra EfomeKwame.

21. References
1.CDC. (2020, March 28).COVID Data Tracker. Centers for Disease Control and Prevention.
https://covid.cdc.gov/covid-data-tracker/#datatracker-home
2.Silver, S. A. et al. The prevalence of acute kidney injury in patients hospitalized with COVID-19 infection: a systematic
review and meta-analysis.Kidney Med.3, 83–98 (2021).
3.Doumas, M., Patoulias, D., Katsimardou, A., Stavropoulos, K., Imprialos, K., & Karagiannis, A. (2020). COVID19 and
increased mortality in African Americans: socioeconomic differences or does the renin angiotensin system also
contribute?Journal of Human Hypertension,34(11), 764–767. https://doi.org/10.1038/s41371-020-0380-y
4.Huang, C., Huang, L., Wang, Y., Li, X., Ren, L., Gu, X., Kang, L., Guo, L., Liu, M., Zhou, X., Luo, J., Huang, Z., Tu, S.,
Zhao, Y., Chen, L., Xu, D., Li, Y., Li, C., Peng, L., & Li, Y. (2021). 6-month consequences of COVID-19 in patients
discharged from hospital: a cohort study. The Lancet, 397(10270), 220–232. https://doi.org/10.1016/s0140-
6736(20)32656-8
5. BhatrajuPK, WurfelMM, Himmelfarb J. Trajectory of kidney function: the canary in sepsis. Am J Respir Crit Care
Med 2020; 202: 1211–12.
6.Macedo, E., Zanetta, D. M. T., & Abdulkader, R. C. R. M. (2012). Long-Term Follow-Up of Patients after Acute Kidney
Injury: Patterns of Renal Functional Recovery. PLoSONE, 7(5), e36388. https://doi.org/10.1371/journal.pone.0036388
https://doi.org/10.1038/s41581-021-00487-3
7.

22. References
7.Yende, S., & Parikh, C. R. (2021). Long COVID and kidney disease. Nature Reviews
Nephrology, 17(12), 792–793.