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Biomedical Research Bulletin

Biomed Res Bull. 2(1):12-17. doi: 10.34172/biomedrb.2024.03

Review Article

Antibiotic Prescription and Its Impact on COVID-19 Patient Recovery: A Cross-sectional Study

Morteza Atayi 1, * ORCID logo, Hasan Hosainzadegan 2 ORCID logo, Nasim Mahdavi 1 ORCID logo, Saba Hashemi 3 ORCID logo, Marzieh Hoseinzadeh 4 ORCID logo, Farzaneh Ahmadizadeh 5 ORCID logo

Author information:
1Research Center for Evidence-Based Medicine, Iranian EBM Center: A Joanna Briggs Institute Center of Excellence, Tabriz University of Medical Sciences, Tabriz, Iran
2Department of Basic Sciences, Maragheh University of Medical Sciences, Maragheh, Iran
3Department of Surgery, Shahid Madani Hospital, Tabriz University of Medical Sciences, Tabriz, Iran
4Department of Surgery, Taleghani Hospital, Tabriz University of Medical Sciences, Tabriz, Iran
5Faculty of Nursing and Midwifery, Maragheh University of Medical Sciences, Maragheh, Iran

*Corresponding Author: Morteza Atayi, Email: m.atayi6722@gmail.com

Abstract

Background:

COVID-19, a newly discovered infectious disease, with a wide range of intensity, has recently become the primary global health issue. Antibiotics are medications designed against microorganisms that are typically not effective in viral infections such as COVID-19. Considering that more than a third of physicians prescribe antibiotics for COVID-19 patients, it was essential to examine the efficacy of these medications.

Methods:

This cross-sectional study was conducted on 128 hospitalized COVID-19 patients in Iran and performed appropriate statistical tests, including the Chi-square test, and regression analyses, using SPSS 26 (IBM, USA). The missing data were managed properly.

Results:

The study included 128 COVID-19 patients with a mean age of 58.7 years, and 46.9% were male. Age was the only factor significantly associated with mortality and hospitalization. However, patients with abnormal potassium, prothrombin, partial thromboplastin time, urea, creatinine, and albumin levels had significantly different hospitalization periods and mortality rates. The most commonly prescribed antibiotics were ceftriaxone, hydroxychloroquine, and azithromycin. In addition, patients who took vancomycin had a significantly higher mortality rate.

Conclusion:

Our findings revealed that age and gender could significantly impact hospital stay duration and mortality rates. Considering that certain antibiotics were linked to prolonged hospital stays, bacterial infection during COVID-19 was not significantly related to increased mortality, which questions the necessity of antibiotics for all patients. The study identified age, gender, and certain lab parameters as associated factors with COVID-19 outcomes. Since its retrospective nature and small sample size limit the findings’ applicability, larger studies are needed to confirm the findings and explore other potential risk factors.

Keywords: COVID-19, Antibiotic, Recovery

Copyright and License Information

© 2024 The Author(s).
This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Funding Statement

This research was conducted with the financial support of the Student Research Committee at Maragheh University of Medical Sciences, Maragheh, Iran (Grant No: 1-3067d-64).

Introduction

The emergence of the coronavirus as a pandemic in December 2019 posed a unique challenge for the healthcare community worldwide. SARS-CoV-2 was first detected during the examination of an unknown type of pneumonia in Wuhan, China. Since then, it has rapidly spread across the globe, infecting millions of people and causing widespread disruption to daily life. COVID-19 is highly contagious and can cause severe respiratory illness, leading to hospitalization and even death.1,2

The severity of the COVID-19 infection can vary widely, with some patients experiencing mild symptoms and others becoming critically ill. Studies of previous influenza pandemics have shown that bacterial co-infection and secondary bacterial infection are important risk factors for patients’ severity and mortality rate. In the case of COVID-19, the prevalence of bacterial infection in intensive care unit patients has been reported to range from 14% to 100% and to be associated with a higher risk of death.3-5

Antibiotics are a group of drugs prescribed to suppress microorganisms. While antibiotics are not effective against viral infections such as COVID-19, they may be used to treat bacterial co-infections that could occur. There is concern that the increased use of antibiotics during the COVID-19 pandemic could exacerbate the current global epidemic of antimicrobial resistance. An online survey conducted at the end of March 2019 revealed that 33% of an international group of physicians reported prescribing hydroxychloroquine (or chloroquine) to COVID-19 patients, and 41% had prescribed azithromycin or similar antibiotics.6,7

A study by Liu et al showed that antibiotic treatment is associated with increased mortality, and most patients gain no benefit from antibiotics. They further found that only 3.2% of COVID-19 patients with bacterial co-infection or secondary bacterial infection had benefited from antibiotic treatment, while 57.1% of patients who received antibiotics did not have experiences of bacterial co-infection or secondary bacterial infection.8

In addition to the use of antibiotics, other treatments have been used to manage COVID-19 patients, including antiviral drugs, steroids, and immunomodulators. The World Health Organization recommends corticosteroid use in patients with severe and critical COVID-19, as they have been shown to reduce mortality in these patients.9

Given that over a third of physicians prescribe antibiotics for COVID-19 patients, it was necessary to investigate their effectiveness in hospitalized COVID-19 patients in Maragheh hospitals.10 Accordingly, this study aims to contribute to the understanding of the use of antibiotics in the treatment of COVID-19 patients. The study evaluated the effectiveness of antibiotics in COVID-19 patients’ recovery.


Methods

This cross-sectional study utilized archived data from all three university hospitals in Maragheh, Iran, to investigate the effectiveness of prescribed antibiotics in hospitalized COVID-19 patients. The study population included all patients admitted to these hospitals between March 20 and September 20, 2020. The sample size was estimated at 128, using appropriate statistical methods, with a margin of error of 5% and a 95% confidence interval.

Descriptive and analytical statistics, including an independent sample t-test, Chi-square test, and logistic regression analyses, were performed using SPSS 26 (IBM, USA) to identify any significant relationships between variables and outcomes. The significance level was set at 0.05.

To ensure ethical considerations were met, the Ethical Committee of Maragheh University of Medical Sciences approved the study protocol. We also followed the Strengthening the Reporting of Observational Studies in Epidemiology reporting guideline to ensure that the study was properly reported. This guideline provides a checklist of 22 items that authors should address when reporting observational studies, including study design, participant characteristics, statistical methods, and results.

In addition to the used statistical methods, it is important to note that data collection was performed retrospectively. This implies that the study was limited by the data available in the records. The missing data were managed by proper methods; however, any missing or incomplete data may have influenced the results.


Results

A total of 128 patients were included in this study. The mean age of the patients was 58.7 years (SD = 17.76), and 46.9% were male. The two most common comorbidities among the patients were high blood pressure and diabetes. Out of all the patients, though only 5.5% indicated bacterial infection (white blood cell > 10 000, C-reactive protein > 50, and Temperature > 38), 82.8% received antibiotics during their hospitalization. The average duration of hospitalization was 6.96 days (SD = 3.83) (Table 1). The overall mortality rate among the patients was 12.5%. Among those who received antibiotics, the mortality rate was 14.2%.


Table 1. Demographic Profile of the Study Participants (N = 128)
No. %
Gender
Female 68 53.1
Male 60 46.9
Age (y) Mean: 58.69 SD: 17.76
Residence
Urban 85 66.4
Rural 43 33.6
Hospitalization period (day) Mean: 6.96 SD: 3.83
Discharge
Recovery 112 87.5
Death 16 12.5
Underlying disease
Yes 48 37.5
No 80 62.5
Diabetes 14 10.9
High blood pressure 33 25.8
Asthma 6 4.7
Heart disease 7 5.5
Cancer 1 0.8
Neurological disease 6 4.7
Antibiotic consumption
Yes 103 80.5
No 25 19.5
CT scan
Clear 3 2.3
Not definitive 98 76.6
Suspected 20 15.6
Infected 7 5.5
PCR test
Positive 68 53.1
Negative 4 3.1
Not definitive 56 43.8

Note. SD: Standard deviation; CT: Computed tomography; PCR: Polymerase chain reaction.

Logistic regression analysis demonstrated that except for age (P = 0.02, odds ratio = 0.954), factors such as gender, type of residence, a history of underlying diseases, and bacterial co-infection were not significantly associated with mortality (Table 2).


Table 2. Logistic Regression Analysis: Examining Mortality as an Outcome*
B SE Wald df Sig. Exp (B)
Gender -1.052 0.620 2.880 1 0.090 0.349
Age -0.048 0.021 5.308 1 0.021 0.954
Type of residence 0.367 0.633 0.335 1 0.563 1.443
Underlying disease 0.175 0.638 0.076 1 0.783 1.192
Bacterial co-infection -1.020 0.950 1.153 1 0.283 0.361
Constant 5.306 1.660 10.217 1 0.001 201.454

Note. B: Estimated logit coefficient; SE: Standard error; df: Degree of freedom; Sig.: Significance level; Exp (B): Exponential value of B.

*Dependent variable: Mortality.

In addition, according to linear regression analysis, except for age and gender (P = 0.004 and 0.006, respectively), type of residence, history of underlying diseases, and bacterial co-infection had no association with the hospitalization period. Older people and women had more hospital stays (Table 3).


Table 3. Linear Regression Analysis: Hospitalization Duration as the Dependent Variable*
Unstandardized Coefficients Standardized Coefficients t Sig. 95.0% Confidence Interval for B
B SE Beta Lower Bound Upper Bound
Constant 2.032 1.611 1.261 0.210 -1.163 5.226
Gender 2.040 0.732 0.256 2.785 0.006 0.587 3.492
Age 0.062 0.021 0.275 2.926 0.004 0.020 0.104
Type of residence 0.703 0.823 0.081 0.854 0.395 -0.930 2.336
Underlying disease -0.087 0.755 -0.011 -0.115 0.908 -1.585 1.410
Bacterial co-infection -0.161 1.514 -0.010 -0.106 0.916 -3.162 2.841

Note. Sig.: Significance level; SE: standard error.

*Dependent variable: Hospitalization period (day).

Based on the patients’ computed tomography (CT) scan and polymerase chain reaction (PCR) results since they were tested during admission, patients with different CT scan results (not definitive, doubtful, infected, and healthy) demonstrated a significant difference in the hospitalization period (P = 0.002) but not in mortality (P= 0.854). On the other hand, there were no significant differences in the hospitalization period or mortality in patients with different PCR results (Table 4).


Table 4. Test Results During Admission and Dischargea
No. (%) Hospitalization Period Mortality
Admission Discharge P Valueb P Valuec
Admission Discharge Admission Discharge
WBC Mean: 7300.43
(SD: 3424.63)
Mean: 7865.44
(SD: 5344.8)
0.580 0.727 0.350 0.002
CRP Mean: 282.90
(SD: 1833.67)
Mean: 47.82
(SD: 21.98)
0.422 0.285 0.259 0.538
CT scan
Not definitive 98 (76.6) - 0.002 - 0.854 -
Doubtful 20 (15.6) -
Infected 7 (5.5) -
Healthy 3 (2.3) -
PCR
Not definitive 56 (43.8) - 0.121 - 1.000 -
Positive 68 (3.1) -
Negative 4 (53.1) -
Blood pressure 20 (15.6) 2 (1.6) 0.550 0.270 1.000 1.000
Hct 23 (18) 10 (7.8) 0.245 0.085 0.164 0.612
Hb 5 (3.9) 0 0.088 - 0.117 -
RBC 4 (3.1) 0 0.081 - 0.418 -
Na 5 (3.9) 1 (0.8) 0.617 0.187 1.000 0.125
Mg 7 (5.5) 1 (0.8) 0.912 0.291 0.595 1.000
K 17 (13.3) 11 (8.6) 0.023 0.963 0.008 0.628
P 9 (7) 0 0.525 - 0.601 -
Ca 12 (9.4) 2 (1.6) 0.348 0.324 1.000 1.000
Urea 14 (10.9) 9 (7) 0.390 0.001 0.016 0.001
Albumin 7 (5.5) 8 (6.3) 0.230 0.011 1.000 1.000
Prothrombin 3 (2.3) 3 (2.3) 0.001 0.718 1.000 0.332
Creatinine 18 (14.1) 12 (9.4) 0.237 0.001 0.050 0.044
Cholesterol 3 (2.3) 0 0.850 - 1.000 -
ALP 4 (3.1) 1 (0.8) 0.545 0.802 1.000 1.000
PT 8 (6.3) 6 (4.7) 0.232 0.834 1.000 0.163
PTT 4 (3.1) 2 (1.6) 0.045 0.499 0.418 1.000
ESR 35 (27.3) 2 (1.6) 0.720 0.864 1.000 1.000
SGPT 6 (4.7) 5 (3.9) 0.278 0.424 0.559 1.000
LDH 17 (13.3) 10 (7.8) 0.479 0.393 0.446 0.612
CPK 1 (0.8) 2 (1.6) 0.992 0.472 1.000 1.000
INR 1 (0.8) 1 (0.8) 0.992 0.187 1.000 1.000
MCH 2 (1.6) 0 0.493 - 1.000 -
AST 6 (4.7) 0 0.169 - 0.559 -
ALT 5 (3.9) 0 0.979 - 0.493 -

Note. SD: Standard deviation; WBC: White blood cell; CRP, CT: Computed tomography; PCR: Polymerase chain reaction; Hct: Hematocrit; Hb: Hemoglobin; RBC: Red blood cell; Na: Sodium; Mg: Magnesium; K: Potassium; P: Phosphorus; Ca: Calcium; ALP: Alkaline phosphatase; PT: Prothrombin; PTT: Partial thromboplastin time; ESR: Erythrocyte sedimentation rate; SGOT: Serum glutamic oxaloacetic transaminase; SGPT: Serum glutamic pyruvic transaminase; LDH: Lactic dehydrogenase; CPK: Creatine phosphokinase; INR: International normalized ratio; MCH: Mean corpuscular hemoglobin; AST: Aspartate aminotransferase; ALT: Alanine transaminase; ANOVA: Analysis of variance.

aBased on frequencies of abnormalities, bPearson’s correlation, one-way ANOVA, and independent sample t-test, cIndependent sample t-test, chi-square, and Fisher’s exact test.

Patients with abnormal potassium, prothrombin, and partial thromboplastin time results during admission blood tests had a significantly different hospitalization period (P= 0.023, 0.001, and 0.045, respectively). In addition, patients with abnormal potassium and urea results had significantly different mortality rates (P = 0.008 and 0.016, respectively). Furthermore, there were significant differences in the hospitalization period and mortality between patients with abnormal urea (P= 0.001 and 0.001), creatinine (P= 0.001 and 0.044), and albumin (P= 0.011 and 1.000) in blood tests during discharge and patients with normal results (Table 4).

According to archived data, the most commonly prescribed antibiotics were ceftriaxone, hydroxychloroquine, and azithromycin (52.3%, 45.3%, and 35.9%, respectively). Significant differences were found in the hospitalization period between patients who took vancomycin and gentamycin (P= 0.003 and 0.015, respectively). Moreover, in patients who took vancomycin, the mortality rate was significantly higher than in other patients (P= 0.002, Table 5).


Table 5. Effects of Antibiotic Usage on Hospitalization Duration and Mortality in COVID-19 Patients
N % Hospitalization Period Mortality
Day (SD) P Valuea Count P Valueb
Ceftriaxone 67 52.3 7.15 (3.58) 0.564 7 0.594
Ciprofloxacin 2 1.6 7.5 (0.71) 0.456 0 1.000
Clindamycin 8 6.3 6.75 (2.44) 0.814 1 1.000
Metronidazole 3 2.3 7 (5.29) 0.991 0 1.000
Meropenem 4 3.1 9 (2.83) 0.234 1 0418
Vancomycin 6 4.7 11.5 (6.83) 0.003 4 0.002
Azithromycin 46 35.9 8.13 (4.3) 0.015 6 1.000
Gentamicin 1 0.8 Missing - 0 1.000
Hydroxychloroquine 58 45.3 7.41 (3.73) 0.222 8 0.791

Note. SD: Standard deviation.

aIndependent sample t-test, bChi-square (Fisher’s exact test for tests that have an expected count less than 5).

Despite the missing data, there was a significant relationship between ceftriaxone prescribed dosage and hospitalization period (P= 0.006, Table 6).


Table 6. Correlation of Antibiotic Dosage With Hospitalization Duration and Mortality in COVID-19 Patients
Mean Dosage mg (SD) Mortality Hospitalization Period
All Recovered Died P Valuea P Valueb
Ceftriaxone 30.56 (23.1) 31.86 (22.9) 21 (24.33) 0.340 0.006
Ciprofloxacin Missing Missing Missing - -
Clindamycin 101.6 (120.22) 123 (127.35) 16 0.507 0.054
Metronidazole 25 (10.54) 25 (10.54) - - -
Meropenem 63 (12.73) 63 (12.73) - - -
Vancomycin 105 (69.52) - 105 (69.52) - 0.400
Azithromycin 36.43 (53.82) 36.43 (53.82) - - 0.263
Gentamicin Missing Missing Missing - -
Hydroxychloroquine Missing Missing Missing - -

Note. SD: Standard deviation. aIndependent sample t-test, bSpearman’s correlation.


Discussion

Our findings indicated that age and gender are two important factors that have significant associations with both a longer duration of hospital stay and higher mortality rates among COVID-19-infected patients. This is in line with the findings of previous studies, which have shown that older individuals and those with underlying medical conditions, such as hypertension, diabetes, and cardiovascular diseases, are at increased risk of poor outcomes following COVID-19 infection.11

Additionally, it was revealed that the presence of bacterial co-infection was not significantly associated with increased mortality rates; this finding leads us to the conclusion that administering antibiotics may not be necessary for all patients infected with COVID-19, especially those with non-severe illnesses. However, the impact of antibiotics may remain uncertain because 82.8% of patients in our study received antibiotic therapy, and 14.2% of them died. Based on the findings of Akbariqomi et al, antibiotic treatment was associated with adverse drug reactions in a significant proportion of patients who did not have a bacterial co-infection.12 The other alternative reason could be that bacterial infections are a sign of severity, and these patients are more likely to die.

Abnormal levels of electrolytes (potassium, prothrombin, and partial thromboplastin time) and renal function tests (urea, creatinine, and albumin) during admission were significantly associated with a longer duration of hospital stay and higher mortality rates. This finding, which conforms to the findings of Vihinen et al, suggests that monitoring these laboratory parameters could be useful in predicting the severity of disease and outcomes among COVID-19-infected individuals.13

According to our analysis, there was a significant association between the use of certain antibiotics (vancomycin and gentamycin) and the prolonged length of hospital stay among COVID-19-infected individuals. However, there was no significant association between the use of ceftriaxone, azithromycin, and hydroxychloroquine and either length of hospital stays or mortality rates.

The limitations of this study include the retrospective nature of the data collection, which may have led to incomplete or missing data. Despite this limitation, the use of archived data allowed researchers to study a large number of patients over a relatively long period of time, providing valuable insights into the effectiveness of antibiotics in COVID-19 patients. Further studies with larger sample sizes and the inclusion of other potential risk factors are warranted to confirm these findings.


Conclusion

Our findings confirmed that age, gender, and laboratory parameters such as electrolytes and renal function tests influence clinical outcomes in COVID-19 patients. However, the study has limitations, including its retrospective nature and relatively small sample size. The call for further studies with larger sample sizes and the inclusion of other potential risk factors indicates that this is an area of research that is still evolving and that there’s much more to learn about how different factors affect COVID-19 outcomes.


Acknowledgements

We would like to extend our sincere appreciation to the esteemed officials of this institution for their invaluable contributions.


Authors’ Contribution

Conceptualization: Morteza Atayi, Hasan Hosainzadegan.

Data curation: Morteza Atayi.

Formal analysis: Morteza Atayi.

Funding acquisition: Nasim Mahdavi.

Investigation: Saba Hashemi, Marzieh Hoseinzadeh, Farzaneh Ahmadizadeh.

Methodology: Morteza Atayi, Hasan Hosainzadegan.

Project administration: Morteza Atayi, Nasim Mahdavi.

Resources: Marzieh Hoseinzadeh, Farzaneh Ahmadizadeh.

Supervision: Hasan Hosainzadegan.

Validation: Saba Hashemi, Marzieh Hoseinzadeh.

Visualization: Farzaneh Ahmadizadeh.

Writing–original draft: Morteza Atayi, Nasim Mahdavi.

Writing–review & editing: Hasan Hosainzadegan.


Competing Interests

The authors declare that they have no conflict of interests.


Ethical Approval

The Ethical Committee of Maragheh University of Medical Sciences approved the study protocol (IR.MARAGHEHPHC.REC.1400.005).


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Submitted: 13 Feb 2024
Accepted: 13 Mar 2024
First published online: 29 Mar 2024
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