Multiple categories of non-cardiac QT-prolonging drugs are associated with increased risk of out-of-hospital cardiac arrest: real-world data from a population-based study

[Associated factors with the occurrence of in-hospital cardiac arrest in patients admitted to internal medicine wards for non-cardiovascular causes]

BACKGROUND AND OBJECTIVE

In-hospital cardiac arrest (IHCA) has a low survival rate, so it is essential to recognize the cases with the highest probability of developing it. The aim of this study is to identify factors associated with the occurrence of IHCA.

MATERIAL AND METHODS

A single-center case-control study was conducted including 65 patients admitted to internal medicine wards for non-cardiovascular causes who experienced IHCA, matched with 210 admitted controls who did not present with IHCA.

RESULTS

The main reason for admission was pneumonia. The most prevalent comorbidity was arterial hypertension. Four characteristics were strongly and independently associated with IHCA presentation, these are electrical left ventricular hypertrophy (LVH) (OR: 13.8; 95% IC: 4.7-40.7), atrial fibrillation (OR: 9.4: 95% CI: 4.3-20.6), the use of drugs with known risk of torsades de pointes (OR: 2.7; 95% CI: 1.3-5.5) and the combination of the categories known risk plus conditional risk (OR: 17.1; 95% CI: 6.7-50.1). The first two detected in the electrocardiogram taken at the time of admission.

CONCLUSION

In admitted patients for non-cardiovascular causes, the use of drugs with a known risk of torsades de pointes, as well as the detection of electrical LVH and atrial fibrillation in the initial electrocardiogram, is independently associated with a higher probability of suffering a IHCA.

Developing a Model for Quantifying QTc-Prolongation Risk to Enhance Medication Safety Assessment: A Retrospective Analysis

There are currently no established methods to predict quantitatively whether the start of a drug with the potential to prolong the QTc interval poses patients at risk for relevant QTc prolongation. Therefore, this retrospective study aimed to pave the way for the development of models for estimating QTc prolongation in patients newly exposed to medications with QTc-prolonging potential. Data of patients with a documented QTc prolongation after initiation of a QTc-prolonging drug were extracted from hospital charts. Using a standard model-building approach, general linear mixed models were identified as the best models for predicting both the extent of QTc prolongation and its absolute value after the start of a QTc-time-prolonging drug. The cohort consisted of 107 adults with a mean age of 64.2 years. Patients were taking an average of 2.4 drugs associated with QTc prolongation, with amiodarone, propofol, pipamperone, ondansetron, and mirtazapine being the most frequently involved. There was a significant but weak correlation between measured and predicted absolute QTc values under medication (r2 = 0.262, p < 0.05), as well as for QTc prolongation (r2 = 0.238, p < 0.05). As the developed models are based on a relatively small number of subjects, further research is necessary to ensure their applicability and reliability in real-world scenarios. Overall, this research contributes to the understanding of QTc prolongation and its association with medications, providing insight into the development of predictive models. With improvements, these models could potentially aid healthcare professionals in assessing the risk of QTc prolongation before adding a new drug and in making informed decisions in clinical settings.

Fluoroquinolones do not provide added risk of out-of-hospital cardiac arrest: a nationwide study

AIM

Conflicting results have been reported regarding the association between fluoroquinolones (FQs) and the risk of out-of-hospital cardiac arrest (OHCA). In particular, it has not become clear whether OHCA in FQ users is related to the inherent comorbidities or whether there is a direct pro-arrhythmic effect of FQs. Therefore, we studied the relation between FQs and OHCA in the general population.

METHODS

Through Danish nationwide registries, we conducted a nested case-control study with OHCA cases of presumed cardiac causes and age/sex/OHCA date-matched non-OHCA controls from the general population. Conditional logistic regression models with adjustments for well-known risk factors of OHCA were employed to estimate the OR with 95% CI of OHCA comparing FQs with amoxicillin.

RESULTS

The study population consisted of 46 578 OHCA cases (mean: 71 years (SD: 14.40), 68.8% men) and 232 890 matched controls. FQ was used by 276 cases and 328 controls and conferred no increase in the odds of OHCA compared with amoxicillin use after controlling for the relevant confounders (OR: 0.91 (95% CI: 0.71 to 1.16)). The OR of OHCA associated with FQ use did not vary significantly by age (OR≤65: 0.96 (95% CI: 0.53 to 1.74), OR>65: 0.88 (95% CI: 0.67 to 1.16), p value interaction=0.7818), sex (ORmen: 0.96 (95% CI: 0.70 to 1.31), ORwomen: 0.80 (95% CI: 0.53 to 1.20), p value interaction=0.9698) and pre-existing cardiovascular disease (ORabsent: 1.02 (95% CI: 0.57 to 1.82), ORpresent: 0.98 (95% CI: 0.75 to 1.28), p value interaction=0.3884), including heart failure (ORabsent: 0.93 (95% CI: 0.72 to 1.22), ORpresent: 1.11 (95% CI: 0.61 to 2.02), p value interaction=0.7083) and ischaemic heart disease (ORabsent: 0.85 (95% CI: 0.64 to 1.12), ORpresent: 1.38 (95% CI: 0.86 to 2.21), p value interaction=0.6230).

CONCLUSION

Our findings do not support an association between FQ exposure and OHCA in the general population. This lack of association was consistent in men and women, in all age categories, and in the presence or absence of cardiovascular disease.