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COVID-19 and Risk for Stillbirth and Preterm Birth

PURPOSE:

  • Khalil et al. (JAMA, 2020) analyzed the association between COVID-19 and risk for stillbirth and preterm delivery        

METHODS:

  • Retrospective cohort study
    • St George’s University Hospital, London (UK)
  • Compared 2 time periods
    • Prepandemic: October 1, 2019, to January 31, 2020
    • Pandemic (following first reported cases in UK of COVID-19): February 1, 2020, to June 14, 2020
  • Outcomes
    • Stillbirth | Preterm birth | Cesarean delivery | NICU admission
    • Repeat analysis performed with exclusion of terminations for fetal anomalies (IN UK, stillbirth includes late termination ≥24 weeks)

RESULTS:

  • Prepandemic
    • 1681 births | 1631 singletons | 22 twins | 2 triplets
  • Pandemic period
    • 1718 births: 1666 singleton | 26 twins
  • Nulliparity was less common during the pandemic period (P < .001)
    • Prepandemic: 52.2%
    • Pandemic: 45.6%
  • Fewer pregnancies were complicated by hypertension during the pandemic period (P = .005)
    • Prepandemic: 5.7%
    • Pandemic period: 3.7%
  • Stillbirth incidence was increased during the pandemic period
    • Prepandemic: 2.38 per 1000 births (n=4)
    • Pandemic: 9.31 per 1000 births (n=16)
    • Difference: 6.93 per 1000 births (95% CI, 1.83-12.0; P = .01)
  • Stillbirth incidence remained elevated after exclusion of terminations for anomalies
    • Prepandemic: 1.19 per 1000 births
    • Pandemic: 6.98 per 1000 births
    • Difference: 5.79 (95% CI, 1.54-10.1; P = .01)
  • There were no significant differences identified for the following outcomes
    • Preterm deliveries (<37 weeks)
    • NICU admission
  • No cases of stillbirth were associated with COVID-19
    • None of the mothers had symptoms associated with COVID-19
    • No placental or postmortem exams suggested of COVID-19
    • Note: Universal testing for SARS-CoV-2 only began May 28, 2020

CONCLUSION:

  • Stillbirth rates were increased during the pandemic vs prepandemic period
    • One important limitation noted by authors is lack of data on cause of the stillbirth
  • Possible reasons for increase in stillbirth rate
    • Increase may still be due to SARS-CoV-2 infection in asymptomatic women (who would not have been tested)
    • Women may have deferred care due to COVID-19 concerns (e.g. delaying care to avoid infection)
    • Possible change in practice resulting in fewer antenatal visits or ultrasound assessments
    • Chance: Study time frame was short | If study was longer, difference perhaps would resolve
    • Hospital may have received more referrals 

Learn More – Primary Sources:

Change in the Incidence of Stillbirth and Preterm Delivery During the COVID-19 Pandemic

CDC Reports on Pregnancy and COVID-19 Outcomes

NOTE: Information and guidelines may change rapidly. Check in with listed references in ‘Learn More – Primary Sources’ to best keep up to date

SUMMARY:

The CDC now includes a separate page on COVID-19 and pregnancy data (see ‘Learn More – Primary Sources’). The initial dataset is based on the MMWR review (June 26, 2020) and the page will be updates as new data becomes available

Summary of MMWR study

Methods

  • CDC receives reports of COVID-19 cases through
    • Electronic standardized case report form or The National Notifiable Diseases Surveillance System
    • Data updated by health departments
    • Case reports for this study: January 22 to June 7 and updated as of June 17, 2020
  • Participants
    • Women aged 15 to 44 years (reproductive age) from 50 states, the District of Columbia, and New York City
    • Lab confirmed SARS-CoV-2 infection
  • Data collected included
    • Demographics | Pregnancy status | Underlying medical conditions | Clinical course | Outcomes (maternal)
  • Missing data
    • To avoid overestimating the risk for adverse outcomes, “Outcomes with missing data were assumed not to have occurred (i.e., if data were missing on hospitalization, women were assumed to not have been hospitalized)”
  • Statistical analysis
    • Outcomes: Logistic regression, using crude and adjusted risk ratios and 95% CIs
    • Risk ratios (RR) adjusted for
      • Age | Presence of underlying chronic conditions | Race/ethnicity

Results

  • Women of reproductive age and positive for SARS-CoV-2: 326,335
  • Pregnancy status
    • 28% (91,412) of all reproductive age women had pregnancy status available | Among those women with pregnancy information, 9% (8,207) were reported as pregnant
  • Symptoms
    • Cough: Similar between pregnant and nonpregnant women (>50%)
    • Shortness of breath: Similar between pregnant and non-pregnant (30%)
    • Pregnant women less frequently reported
      • Headache | Muscle aches | Fever | Chills | Diarrhea
  • Comorbidities
    • More frequently reported in pregnant women
      • Chronic lung disease | Diabetes mellitus | CVD
  • Hospitalization
    • Significantly higher in pregnant women (adjusted)
    • Pregnant: 31.5% | Nonpregnant: 5.8%
    • aRR: 5.4 (95% CI, 5.1 to 5.6)
  • ICU admission
    • Significantly higher in pregnant women (adjusted)
    • Pregnant: 1.5% | Nonpregnant: 0.9%
    • aRR: 1.5 (95% CI, 1.2 to 1.8)
  • Mechanical ventilation
    • Significantly higher in pregnant women (adjusted)
    • Pregnant: 0.5% | Nonpregnant 0.3%
    • aRR: 1.7 (95% CI, 1.2 to 2.4)
  • Maternal mortality
    • There was no difference between groups
    • Pregnant : 0.2% (16 patients) | Nonpregnant: 0.2% (208 patients)
    • aRR: 0.9 (95% CI, 0.5 to 1.5)

Conclusions

  • Limitations include
    • Pregnancy status was missing for approximately 75% of women of reproductive age
    • Data on race/ethnicity, symptoms, underlying conditions, and outcomes were missing “for a large proportion of cases”
    • Data not available for the following
      • Trimester at time of infection was not available
      • Whether hospitalization was related to COVID-19
    • Current routine case surveillance does not capture pregnancy or birth outcomes
  • CDC concludes that

These findings suggest that among women of reproductive age with COVID-19, pregnant women are more likely to be hospitalized and at increased risk for ICU admission and receipt of mechanical ventilation compared with nonpregnant women, but their risk for death is similar

Learn More – Primary Sources:

CDC (MMWR): Characteristics of Women of Reproductive Age with Laboratory-Confirmed SARS-CoV-2 Infection by Pregnancy Status — United States, January 22–June 7, 2020

CDC: Data on COVID-19 During Pregnancy

CDC Who Needs Extra Precautions: People of Any Age with Underlying Medical Conditions

ACOG: Novel Coronavirus 2019 (COVID-19)

How Do Clinical Characteristics of COVID-19 Infection Differ Between Symptomatic and Asymptomatic Patients?

BACKGROUND AND PURPOSE:

  • Yang et al. (JAMA Netw Open., 2020) describe clinical characteristics of both symptomatic and asymptomatic patients with confirmed SARS-CoV-2 infection

METHODS:

  • Case series (December 24, 2019, to February 24, 2020)
  • Setting
    • Wuhan, China
  • Participants
    • Consecutive hospitalized cases with lab confirmed COVID-19
    • Recruited from 26 cluster cases who had
      • Confirmed history of exposure to the Hunan seafood market or
      • Close contact with another patient who had been hospitalized for COVID-19
  • Study design
    • RT-PCR on nasopharyngeal swabs was performed every 24 to 48 hours
    • CT scan: On admission with a second chest CT at 4 to 6 days and third CT at 6 to 7 days after the second scan
      • Additional CT for worsening status
    • CD4+T lymphocyte count was tested every 5 to 6 days

RESULTS:

  • 78 patients
    • Median (IQR) number of patients per cluster: 3 (2-3) patients
    • Range: 2 to 10 patients per cluster
  • Symptomatic vs asymptomatic
    • Symptomatic cases: 57.7% of cases (45 patients)
    • Asymptomatic: 42.3% of cases (33 patients)
  • Patients who were asymptomatic tended to
    • Be younger (P < 0.001)
      • Asymptomatic: median (IQR) age 37 (26 to 45) years
      • Symptomatic: 56 (34 to 63) years
    • Be women (P = 0.002)
      • Asymptomatic: 66.7% were women (22 patients)
      • Symptomatic: 31.0% were women (14 patients)
    • Not have biochemical evidence of liver injury (P = 0.03)
      • Asymptomatic: 3% had a liver injury (1 patient)
      • Symptomatic: 20.0% had a liver injury (9 patients)
    • Have higher CD4+T lymphocyte counts  (P = 0.001)
      • Asymptomatic: median (IQR) 719 (538 to 963) per uL
      • Symptomatic: 474 (354 to 811) per ul
    • Have faster lung recovery based on CT scan (P = 0.001)
      • Asymptomatic: median (IQR) duration 9 (6 to 18) days
      • Symptomatic: 15 (11 to 18) days
    • Have a shorter duration of viral shedding on nasopharyngeal swabs (P = 0.001)
      • Asymptomatic: median (IQR) duration 8 (3 to 12) days
      • Symptomatic: 19 (16 to 24) days
    • Have more stable SARS-CoV-2 testing results
      • Asymptomatic: 12.1% had fluctuated results (4 patients)
      • Symptomatic: 33.3% had fluctuated results (15 patients)

CONCLUSION:

  • Compared to symptomatic COVID-19 patients, asymptomatic patients experienced less organ injury and CT scans improved more rapidly
    • Consumption of CD4 lymphocytes was lower, suggesting less damage to the immune system
  • Asymptomatic patients appear to have a shorter duration of viral shedding, suggesting that they may be infectious for a shorter period of time

Learn More – Primary Sources:

Comparison of Clinical Characteristics of Patients with Asymptomatic vs Symptomatic Coronavirus Disease 2019 in Wuhan, China

ICU Admission for COVID-19 and Maternal Outcomes

PURPOSE:

  • Blitz et al. (AJOG, 2020), sought to determine maternal outcomes in pregnant and postpartum women admitted to the ICU with a diagnosis of COVID-19

METHODS:

  • Case series of consecutive admissions (March 1 to May 6, 2020)
    • Large integrated healthcare system
    • System responsible for 40,000 deliveries per year (1% of all US births)
  • Participants
    • Pregnant and postpartum women (immediately following delivery) with laboratory-confirmed COVID-19 and admitted to the ICU
  • Data source
    • Extracted from electronic health record
      • Demographics | Medical comorbidities | Duration of illness prior to hospitalization | Lab results | Radiology Reports | ICU treatments and outcomes

RESULTS:

  • Total of 462 pregnant women tested positive for SARS-CoV-2
    • Severe or critical: 15% (70 patients)
    • 13 of 70 patients (19%) admitted to ICU
    • Mean gestational age at hospitalization: 33.3 weeks
    • Symptom onset: 8±3 days prior to admission
  • Maternal characteristics of patients admitted to ICU
    • Mean maternal age: 33.8 years
    • Multiparous: 69% | All singletons
    • Largest racial/ethnic group: Hispanic (38%)
    • Comorbidities
      • Obesity: 38%
      • Pulmonary conditions: 23% (e.g, asthma and obstructive sleep apena)
      • No comorbidities: 46%

Clinical course of patients admitted to ICU

  • Common clinical findings included tachycardia (77%) and tachypnea (23%) | 02 sat <93% (69%)
  • Fever was uncommon (15%)
  • Common lab findings
    • Lymphopenia | Elevated transaminases | Elevated inflammatory markers
  • Mechanical ventilation: 8 cases (6 postpartum; 2 pregnant)

Treatment

  • Prophylactic or therapeutic anticoagulation: 100%
  • Hydroxychloroquine: 85%
  • Antibiotics for community acquired pneumonia: 92%
  • Enrolled in remdesivir trial: 23%
  • Interleukin-6 receptor inhibitors: 38%
  • Convalescent plasma therapy: 15%

Maternal Mortality

  • Maternal mortality: 2 patients died
  • Patient 1: periviable fetal demise with multisystem organ failure
    • BMI >40 kg/m2 | Obstructive Sleep Apnea
  • Patient 2: “rapid clinical deterioration postpartum”
    • No comorbidities
    • Severe respiratory distress, multiple organ failure and cardiopulmonary arrest

Pregnancy Outcomes

  • Deliveries during hospitalization: 54% (7 patients) | Preterm: 4 deliveries (57%)
  • Cesarean deliveries
    • Respiratory decompensation: 5 patients
    • Cord prolapse (was induced for worsening respiratory status): 1 patient
  • Vaginal delivery: 1 patient

CONCLUSION:  

  • 2 patients (1 pregnant, 1 postpartum) hospitalized with COVID-19 died following ICU admission
    • 15% of patients admitted to ICU and 25% of patients on mechanical ventilation  
  • The authors state

…pregnant and postpartum women admitted to the ICU with COVID-19 are at risk for maternal death, which may occur even in the absence of significant baseline comorbidities

Learn More – Primary Sources:

Maternal Mortality Among Women with COVID-19 Admitted to the Intensive Care Unit

Is There a ‘Preeclampsia-Like’ Syndrome in Pregnant Women with COVID-19?

PURPOSE:

  • There is overlapping symptomatology between preeclampsia (PE) and COVID-19 including liver injury and coagulopathy
    • Being able to differentiate between the two could have significant implications for clinical care as PE with severe features usually requires delivery
  • Mendoza et al. (BJOG, 2020) sought to investigate pregnancies with COVID-19 and determine, based on clinical, ultrasound and biochemical findings if patients with true PE vs ‘PE-like’ features could be distinguished

METHODS:

  • Prospective observational study
    • Tertiary referral hospital
  • Participants
    • Singleton pregnancies
    • Confirmed or suspected COVID-19
    • >20w0d gestation
  • Classified in to two groups: Severe vs nonsevere COVID-19, based on presence of severe pneumonia
  • Aside from clinical outcomes, the following ultrasound and biochemical parameters were also assessed in patients with suspected PE
    • Uterine artery pulsatility index (UtAPI)
    • Angiogenic factors: Soluble fms-like tyrosine kinase-1/placental growth factor (sFlt-1/PlGF)
  • Primary outcome measures
    • Incidence of signs and symptoms related to PE, including
      • Hypertension | Proteinuria | Thrombocytopenia | Elevated liver enzymes | Abnormal UtAPI and increased sFlt-1/PlGF
    • “UtAPI >95th centile for gestational age, and sFlt-1/PlGF values ≥85 (at <34 weeks) or ≥110 (at ≥34 weeks) were considered highly suggestive of underlying placental disease”

RESULTS:

  • 42 consecutive pregnancies were recruited
    • Nonsevere: 34
    • Severe (requiring ICU admission): 8
  • Clinical course of severe group
    • Prior to onset of severe pneumonia, all 8 women were normotensive and only 1 patient had elevated UtAPI
  • Median age of severe cases (39.4 years) were significantly higher than nonsevere (30.9 years); p=0.006
  • Following severe pneumonia onset, 6 women (14.3% of total cohort) met PE criteria including
    • New onset hypertension and proteinuria and/or thrombocytopenia and/or elevated liver enzymes
    • No cases met diagnostic criteria in the nonsevere group
    • All required antihypertensive medication
    • Only 1 patient had abnormal LDH level >600 UI/L, sFlt-1/PlGF, and UtAPI
    • 4 cesarean births
      • HELLP syndrome (1 case)
      • Worsening COVID-19 (3 cases)
  • Two cases were still pregnant after recovery from severe pneumonia
    • PE-like syndrome resolved in both cases

CONCLUSION:

  • Pregnant women with severe COVID-19 can develop a PE-like syndrome
  • The authors suggest that only 1 out of the 8 cases demonstrated ultrasound and biochemical features compatible with placental dysfunction
    • PE-like syndrome vs PE could possibly be differentiated based on these biochemical markers (sFlt-1/PlGF, LDH) and Doppler (UtAPI) features
  • Based on the resolution in 2 of the cases, the authors state that

PE-like syndrome might not be an indication for earlier delivery in itself since it might not be a placental complication and could resolve spontaneously after recovery from severe pneumonia.

Learn More – Primary Sources:

Preeclampsia-like Syndrome Induced by Severe COVID-19: A Prospective Observational Study

Commentary: Can COVID‐19 in pregnancy cause preeclampsia?

RECOVERY RCT ALERT: Dexamethasone Reduces COVID-19 Deaths

SUMMARY:

The ‘Randomised Evaluation of COVid-19 thERapY (RECOVERY) Trial’ is a national program in the UK to study multiple potential therapies for SARS-CoV-2 infection. The program involves thousands of doctors, nurses, pharmacists, and research personnel. The dexamethasone branch of the RECOVERY Trial program was halted on June 8th because the steering committee felt there was sufficient evidence to make a determination whether there was benefit to this therapy. The chief investigators, Professors Horby and Landray, reported the findings on June 16, 2020.

  • The preliminary results found that

Overall dexamethasone reduced the 28-day mortality rate by 17% (0.83 [0.74 to 0.92]; P=0.0007) with a highly significant trend showing greatest benefit among those patients requiring ventilation (test for trend p<0.001)

Methods

Randomized controlled trial (RCT)

  • Participants
    • Patients hospitalized with COVID-19
  • Randomization
    • Dexamethasone 6 mg daily (oral or IV) vs usual care alone
  • Primary Outcomes
    • Within 28 days after randomization: Death | Discharge | Need for ventilation | Need for renal replacement therapy
  • Additional data collected
    • Age | Sex | Major co-morbidity | Pregnancy | COVID-19 onset date and severity

Results

  • Dexamethasone group: 2104 patients | Usual care alone: 4321 patients
  • Usual care group
    • 28-day mortality rates
      • Requiring ventilation: 41%
      • Oxygen only: 25%
      • No respiratory intervention: 13%
  • Dexamethasone group: Reduction in deaths vs usual care alone
    • Requiring ventilation: Rate ratio (RR) 0.65 (95% CI, 0.48 to 0.88]; p=0.0003)
    • Oxygen only: RR 0.80 (95% CI, 0.67 to 0.96; p=0.0021)
    • No respiratory intervention: RR 1.22 (95% CI, 0.86 to 1.75; p=0.14)
  • Need to treat
    • Ventilated patients: 1 death would be prevented by treatment of approximately 8 patients
    • Oxygen alone: 1 death prevented by treatment of approximately 25 patients

KEY POINTS:

  • Reduction in deaths for hospitalized patients with COVID-19 with the use of low dose dexamethasone
    • Reduced deaths by one-third in ventilated patients
    • Reduced deaths by 20% for oxygen only patients   
    • No benefit for patients not requiring respiratory support
  • Full report will be published
  • Professor Hornsby, one of the chief investigators states that

…dexamethasone should now become standard of care in these patients. Dexamethasone is inexpensive, on the shelf, and can be used immediately to save lives worldwide

Learn More – Primary Sources:

RECOVERY TRIAL: Low-cost dexamethasone reduces death by up to one third in hospitalised patients with severe respiratory complications of COVID-19

Dexamethasone in Hospitalized Patients with Covid-19 — Preliminary Report (NEJM)

FDA Revokes Hydroxychloroquine and Chloroquine EUA for the Treatment of COVID-19

SUMMARY:

The FDA has revoked the Emergency Use Authorization (EUA) for chloroquine phosphate and hydroxychloroquine sulfate. Based on the available data, these medications do not appear to be effective in the treatment of COVID-19 and also present harms, specifically related to cardiac arrhythmias.

  • An EUA is different than a full FDA approval
    • EUA based on an FDA evaluation of evidence and risks vs potential or known benefits of “unproven” products during an emergency
  • Chloroquine phosphate and hydroxychloroquine sulfate, donated to the Strategic National Stockpile, received an EUA to be used to treat certain hospitalized patients with COVID-19 when a clinical trial was unavailable, or participation in a clinical trial was not feasible
  • Based on benefits/harms analysis, these medications no longer meet the EUA requirements

KEY POINTS:

  • Research has demonstrated the following regarding hydroxychloroquine and chloroquine (see ‘Related ObG Entries’ below)
    • Hydroxychloroquine showed no benefit on mortality or in speeding recovery (RCT)
    • Suggested dosing regimens for chloroquine and hydroxychloroquine are unlikely to kill or inhibit the virus that causes COVID-19
    • “The totality of scientific evidence currently available indicate a lack of benefit”
  • FDA approved use of chloroquine and hydroxychloroquine
    • Still both FDA-approved to treat or prevent malaria
    • Hydroxychloroquine is also approved to treat autoimmune conditions such as chronic discoid lupus erythematosus, systemic lupus erythematosus in adults, and rheumatoid arthritis

Note: “FDA approved products may be prescribed by physicians for off-label uses if they determine it is appropriate for treating their patients, including during COVID”

Possible Drug Interaction with Remdesivir

  • The FDA also released a warning regarding a potential drug interaction between remdesivir and chloroquine and hydroxychloroquine
  • Data derived from a non-clinical laboratory study demonstrated possible reduction in the antiviral activity of remdesivir activity when co-administered with these medications
  • The FDA is not currently aware of reduced activity in the clinical setting and continues to evaluate data on this subject

Learn More – Primary Sources:

Coronavirus (COVID-19) Update: FDA Revokes Emergency Use Authorization for Chloroquine and Hydroxychloroquine

Coronavirus (COVID-19) Update: FDA Warns of Newly Discovered Potential Drug Interaction That May Reduce Effectiveness of a COVID-19 Treatment Authorized for Emergency Use

Neonatal Infection: COVID-19 and Risk for Vertical Transmission

PURPOSE:

  • Walker et al. (BJOG, 2020) sought to investigate the risk for vertical transmission in women with COVID-19 around the time of delivery
  • A systematic analysis was performed, including an effort to address duplicate reporting in previous studies

METHODS:

  • Systematic review and critical analysis (Search from April through May, 2020)
    • Authors sought out full text copies of any studies that may be eligible for inclusion
  • Eligibility criteria for studies
    • Pregnant women with confirmed (positive test or high clinical suspicion) COVID-19
    • Case reports or case series | No language restriction
  • Rates of infection were determined for the following
    • Mode of birth (cesarean or vaginal)
    • Breast or formula feeding
    • Rooming in or isolation
  • Studies underwent disambiguation to avoid duplication of patients among different reports

RESULTS:

  • 49 studies included
    • 666 neonates | 655 pregnant women
    • 11 twins
  • Infected neonates: 4%
  • Duplicate pregnancies (in Chinese data) were identified and were properly accounted for in subsequent analyses

Mode of Delivery

  • Neonatal infection rates based on mode of delivery
    • Vaginal delivery: 2.7%
    • Cesarean: 5.3%

Breast vs Formula Feeding

  • Among neonates with confirmed COVID-19
    • Breast fed: 7
    • Formula: 3
    • Expressed breast milk: 1
    • Unreported: 17

Rooming In vs Isolation

  • Among neonates with confirmed COVID-19
    • Isolated: 7
    • Rooming in: 5
    • Not reported: 16

CONCLUSION:

  • Overall, there was a low rate of neonatal infection following maternal COVID-19 infection
  • There does not appear to be a greater risk for vertical SARS-CoV-2 transmission based on mode of delivery, breast feeding or rooming in
  • The authors acknowledge limitations including
    • Not all newborns tested for SARS-CoV-2
    • Case series have possibility of bias | More severe cases are more likely to be reported
    • “…disappointing that details of outcome and care” were not available and should be considered a “missed opportunity”
    • Due to low newborn infection rate, ‘n’ of infected neonates is still relatively small and appropriate caution should be used in interpreting the data
  • The authors conclude that

There is no evidence that isolating the baby away from the mother is beneficial if such precautions are taken, and encouraging the baby to spend time with its mother is likely to help with breastfeeding and bonding

We recommend that separation only occurs where this is necessary for clinical indications

Learn More – Primary Sources:

Maternal transmission of SARS‐COV‐2 to the neonate, and possible routes for such transmission: A systematic review and critical analysis

Do Warmer Temperatures Decrease the Incidence of COVID-19?

BACKGROUND AND PURPOSE:

  • Sehra et al. (Clinical Infectious Diseases, 2020) investigated the effects of temperature, precipitation, and UV Light on community transmission of SARS-CoV-2

METHODS:

  • Observational analysis of case data
  • Data analyzed (January 22 to April 3, 2020)
    • Daily reported cases of SARS-CoV-2 and daily weather patterns across the US
  • Analysis
    • Null hypothesis: There is no association between daily temperatures and COVID-19 spread
    • Modeling techniques were used to investigate whether daily maximum temperature, precipitation, UV Index and the SARS-CoV-2 incidence 5 days later were related
    • Sensitivity analyses to assess transmission lags were performed at 3 days, 7 days and 9 days

RESULTS:

  • 974 daily observations
  • Max temperature of >52°F associated with a lower rate of new cases at 5 days
    • Incidence rate ratio (IRR) 0.85 (95% CI 0.76 to 0.96; p = 0.009)

Temperature

  • Temperature <52°F was inversely associated with case rate at 5 days
    • IRR 0.98 (95% CI 0.97 to 0.99; p = 0.001)
  • Modeling results: Rate of new cases was lower for theoretical states where daily temperature remained >52°F
    • At this temperature threshold, modeling predicted that there would be 23-fewer cases per-million per-day by 25 days of the epidemic

UV Index

  • A 1-unit higher UV index associated with a lower rate at 5 days
    • IRR 0.97(95% CI 0.95 to 0.99; p = 0.004)

Precipitation

  • Precipitation was not associated with a greater rate of cases at 5 days
    • IRR 0.98 (95% CI 0.89 to 1.08; p = 0.65)

CONCLUSION:

  • COVID-19 incidence was lower at warmer vs cooler temperatures
    • Incidence declined with increasing temperature until 52°F
  • The authors state that while statistically significant, the actual association is small and therefore

…unlikely to provide significant effect beyond current strategies for mitigation

…although there is an association between daily temperature and subsequent case volume the disease may continue to spread in the United States even in periods of warmer weather

Learn More – Primary Sources:

Maximum Daily Temperature, Precipitation, Ultra-Violet Light and Rates of Transmission of SARS-Cov-2 in the United States

Remdesivir RCT Results: 5 or 10 Day Treatment for Severe COVID-19?

BACKGROUND AND PURPOSE:

  • Remdesivir is an RNA polymerase inhibitor that has antiviral activity against RNA viruses, possibly including SARS-CoV-2
  • Goldman et al. (NEJM, 2020) sought to evaluate the efficacy and safety of a 5-day vs 10-day course of remdesivir for the treatment of severe COVID-19

METHODS:

  • Randomized, open-label, phase III clinical trial (RCT)
  • Participants
    • Hospitalized COVID-19 (confirmed) patients
    • Oxygen saturation <94% on room air
    • Radiologic evidence of pneumonia
  • Intervention
    • 5 days IV remdesivir
    • 10 days IV remdesivir
  • Study design
    • Patients were randomly assigned 1:1
    • All patients received
      • 200 mg of remdesivir on day 1
      • 100 mg of remdesivir on all subsequent days
  • Primary outcome
    • Clinical status on day 1 using a 7-point ordinal scale from days 1 to 14 or until discharge | Worst score (lowest) recorded each day
  • Statistical analysis
    • 400 patients (200 in each group)
    • >85% power to detect an odds ratio (OR) for improvement of 1.75
    • Two-sided significance level of 0.05

RESULTS:

  • 397 patients began treatment
    • 5-day group: 200 patients
      • Median duration of treatment: 5 days
    • 10-day group: 197 patients
      • Median duration of treatment: 9 days
  • 10-day group had significantly worse clinical status at baseline but otherwise 2 groups were demographically balanced
  • Primary outcome
    • There was no statistical difference in clinical improvement between groups at 14 days once adjusting for baseline clinical status (P=0.14)
  • Nor were there any differences in secondary outcomes including
    • Time to recovery
    • Proportion of patients who recovered by days 5, 7, 11 and 14
    • Death from any cause
  • The most common adverse effects (5-day vs 10-day)
    • Nausea: 10% vs 9%
    • Acute respiratory failure: 6% vs. 11%
    • Increased ALT: 6% vs 8%
    • Constipation: 7% in both groups
  • Discontinuation of treatment due to adverse events
    • 4% in the 5-day group vs 10% in the 10-day group
  • Post hoc analysis was performed to determine if there was benefit for any subgroups
    • Patients who progressed to mechanical ventilation: Death by day 14
      • 5-day group: 40%
      • 10-day group: 17%

CONCLUSION:

  • There was no significant difference in patient outcomes with a 5- or 10-day course of remdesivir in patients with severe COVID-19
  • These results can not be extended to patients who are ventilated as most patients were not receiving respiratory support prior to receiving remdesivir
  • The authors note that there was no placebo arm and therefore this study could not determine the efficacy of remdesivir
  • The authors state

Our trial suggests that if remdesivir truly is an active agent, supplies that are likely to be limited can be conserved with shorter durations of therapy

Learn More – Primary Sources:

Remdesivir for 5 or 10 Days in Patients With Severe Covid-19

RCT Results: Does Hydroxychloroquine Work for COVID-19 Postexposure Prophylaxis?

PURPOSE:

  • Boulware et al. (NEJM, 2020) sought to determine if hydroxychloroquine can be used to prevent COVID-19 in individuals who have been exposed to SARS-CoV-2

METHODS:

  • Randomized, double-blind, placebo-controlled trial (RCT)
  • Participants:
    • Asymptomatic
    • Household or occupational exposure to individual with confirmed COVID-19 | <6 feet distance for >10 minutes
      • High-risk exposure: No face mask or eye shield
      • Moderate-risk exposure: Face mask but no eye shield
  • Randomization within 4 days post-exposure
    • Hydroxychloroquine: 800 mg once, followed by 600 mg in 6 to 8 hours, then 600 mg daily for 4 additional days
    • Placebo
  • Primary outcome
    • New COVID-19 (lab confirmed or compatible symptoms if testing unavailable) within 14 days
  • Secondary outcomes included
    • Hospitalization | Death | PCR-confirmed SARS-CoV-2 infection | Symptoms (severity)
  • Statistical analysis
    • Two-sided alpha of 0.05 | 90% power | 50% relative effect size
    • Require 750 participants in each group

RESULTS:

  • 821 participants
    • Hydroxychloroquine: 414
    • Placebo: 407
  • High-risk exposure: 87.6%
  • New illness compatible with COVID-19
    • No difference was detected between groups
      • Hydroxychloroquine: 11.8%
      • Placebo: 14.3%
    • Absolute difference: −2.4 percentage points (95% CI, −7.0 to 2.2; P=0.35)
  • Side effects where higher in the hydroxychloroquine group, although no severe side effects were reported
    • Hydroxychloroquine: 40.1%
    • Placebo: 16.8%

CONCLUSION:

  • The trial was stopped during interim analysis due to futility, with no significant difference between groups
  • The authors concluded

High doses of hydroxychloroquine did not prevent illness compatible with Covid-19 when initiated within 4 days after a high-risk or moderate-risk exposure

Learn More – Primary Sources:

A Randomized Trial of Hydroxychloroquine as Postexposure Prophylaxis for Covid-19