A large-scale retrospective cohort study found that children with asthma who also had supraventricular tachycardia had significantly higher odds of death and/or cardiac arrest compared to those without supraventricular tachycardia—even after controlling for asthma severity and other factors. 

The study, published in Pediatric Pulmonology, analyzed electronic health record data from 91,066 children with asthma aged 2 to 18 years.

Key Findings

Children with asthma and supraventricular tachycardia (SVT) had 4.30 times higher odds of death and/or cardiac arrest after asthma diagnosis compared to those without SVT (95% confidence interval [CI] = 2.50-7.39, P < .001).

SVT prevalence in children with asthma was 0.27%, similar to general pediatric population rates of 0.1% to 0.4%

Patients with asthma and SVT required more intensive asthma treatments, including epinephrine and methylprednisolone.

Increasing age, presence of complex chronic conditions, congenital heart disease, and social determinants of health were independently associated with higher mortality/cardiac arrest risk.

Methods

Researchers utilized the TriNetX electronic health record database to analyze data from January 2, 2006, to May 17, 2023. Subjects were divided into two groups: those with an SVT diagnosis (n = 244) and those without an SVT diagnosis (n = 90,822). The primary outcome was death and/or cardiac arrest after the first asthma diagnosis date.

Multivariable logistic regression analysis was performed to assess the association between SVT and adverse outcomes while controlling for demographic and clinical factors. Asthma severity was estimated using steroid and long-acting beta-agonist (LABA) treatment as surrogates.

Study Details and Further Results

Demographics of the study population were:

• Mean age at first asthma diagnosis: 5.59 years (standard deviation [SD] = 3.80) for SVT group vs 5.90 years (SD = 3.74) for non-SVT group (P = .196)
• Sex distribution: 68.4% male in SVT group vs 60.2% male in non-SVT group (P = .011)
• Race distribution: 62.7% White and 33.6% Black or African American in SVT group vs 52.6% White and 42.5% Black or African American in non-SVT group (P = .008).

Comorbidities in the study population included:

• Congenital heart disease: 34.4% in SVT group vs 2.9% in non-SVT group (P < .001)
  • Simple: 31.1% vs 2.3% (P < .001)
  • Complex non-single ventricle: 23.4% vs 1.4% (P < .001)
  • Complex single ventricle: 7.4% vs 0.1% (P < .001)
• Noncardiovascular complex conditions: 49.6% in SVT group vs 13.8% in non-SVT group (P < .001)
  • Congenital/genetic disorders: 25.0% vs 3.9% (P < .001)
  • Gastrointestinal: 29.1% vs 3.3% (P < .001)
  • Hematology/immunology: 16.0% vs 3.1% (P < .001)
  • Malignancy: 4.1% vs 1.3% (P < .001)
  • Metabolic: 17.2% vs 3.7% (P < .001)
  • Neuromuscular: 20.1% vs 3.5% (P < .001)
  • Renal: 9.8% vs 1.7% (P < .001)
  • Respiratory: 23.4% vs 2.7% (P < .001)
• Social determinants of health: 14.3% in SVT group vs 5.3% in non-SVT group (P < .001).

Medication use:

• SVT patients more frequently received levalbuterol (12.7% vs 1.0%, P < .001), magnesium sulfate (15.6% vs 8.9%, P < .001), methylprednisolone (18.0% vs 11.8%, P = .004), and formoterol (14.3% vs 5.3%, P < .001) than those without SVT.
• Other medications:
  • Dexamethasone: 34.4% vs 34.8% (P = .96)
  • Epinephrine: 9.8% vs 3.4% (P < .001)
  • Ipratropium: 43.9% vs 49.3% (P = .103)
  • Ketamine: 2.5% vs 0.8% (P = .009)
  • Prednisolone: 38.9% vs 41.7% (P = .419)
  • Prednisone: 11.1% vs 8.8% (P = .256)
  • Terbutaline: 0.8% vs 0.5% (P = .842)
  • Long-acting beta-agonists (LABA): 16.4% vs 7.6% (P < .001)
  • Salmeterol: 5.7% vs 3.4% (P = .067)
• Antiarrhythmic medications:
  • Adenosine: 29.1% vs 0.1% (P < .001)
  • Amiodarone: 9.0% vs 0.0% (P < .001)
  • Atenolol: 11.1% vs 0.1% (P < .001)
  • Digoxin: 13.1% vs 0.1% (P < .001)
  • Esmolol: 6.1% vs 0.1% (P < .001)
  • Flecainide: 3.7% vs 0.0% (P < .001)
  • Nadolol: 1.2% vs 0.0% (P < .001)
  • Propranolol: 25.4% vs 0.4% (P < .001)
  • Sotalol: 4.1% vs 0.0% (P < .001).

Medical services:

• SVT patients had higher rates of critical care services use (18.4% vs 5.7%, P < .001), hospitalizations (16.4% vs 8.8%, P < .001), and mechanical ventilation (14.3% vs 1.6%, P < .001) than those without SVT.
• Emergency department services use was 49.6% in SVT group vs 70.1% in non-SVT group (P < .001).

Mortality and cardiac arrest:

• Death after asthma diagnosis: 3.3% in SVT group vs 0.3% in non-SVT group (P < .001)
• Cardiac arrest after asthma diagnosis: 4.5% in SVT group vs 0.2% in non-SVT group (P < .001)
• Combined death and/or cardiac arrest: 6.6% in SVT group vs 0.5% in non-SVT group (P < .001).

Multivariable analysis:

• Adjusted odds ratio for death/cardiac arrest in SVT group: 4.30 (95% confidence interval [CI] = 2.50-7.39, P < .001)
• Other significant factors:
  • Increasing age (odds ratio [OR] = 1.04, 95% CI = 1.01-1.06, P = .002)
  • Complex chronic conditions (OR = 20.10, 95% CI = 15.42-26.20, P < .001)
  • Congenital heart disease (OR = 2.10, 95% CI = 1.69-2.60, P < .001)
  • Social determinants of health (OR = 1.50, 95% CI = 1.14-1.98, P = .004)
• Race (compared to White):
  • Black or African American: OR = 0.68 (95% CI = 0.55-0.84, P < .001)
  • Other races: OR = 1.25 (95% CI = 0.83-1.87, P = .284)

The study authors noted several limitations of the study, including the retrospective design, potential coding inaccuracies in the electronic health records, and inability to determine precise temporal relationships between SVT and asthma onset.

The authors concluded, "Further studies are needed to determine the factors contributing to the increased risk of mortality and/or cardiac arrest in children with asthma and SVT."

One author received funding from the New England Journal of Medicine and Elsevier © Osmosis for educational materials and content. The remaining authors declared no conflict of interest.