Prevalence, predictors and clinical implications of prolonged corrected QT in elderly patients with dementia and suspected syncope

Prevalence of Drugs and Drug Combinations that Increase Risk of Prolonged QT Time Among People with Major Neurocognitive Disorder Living in Sweden: A Cross-Sectional Registry Study

BACKGROUND

People with major neurocognitive disorder might be susceptible to drug-induced QT interval prolongation due to the presence of a number of concomitant risk factors.

OBJECTIVE

The aim of this study was to investigate the prevalence of QT-prolonging drugs and QT-prolonging drug-drug interactions and associated factors among older people with major neurocognitive disorder.

METHODS

In this register-based study, we obtained information regarding QT-prolonging drug use in a large population of older people with major neurocognitive disorder, through record linkage between the Swedish registry for cognitive/dementia disorders, and the Swedish Prescribed Drug Register. QT-prolonging drugs were identified according to the CredibleMeds online database and interactions using the Janusmed interaction database. Drug use was defined as one or more filled prescriptions during a 6-month timeframe, July 01 to December 31, 2017. Associations between people with a QT-prolonging drug and the factors of age and gender were analysed through multiple logistic regression.

RESULTS

Of 35,212 people included in the study, 41.6% had one or more QT-prolonging drug prescribed. The most commonly prescribed drug was donepezil, with a prevalence of 25.0%, followed by citalopram and escitalopram, representing 14.5% and 3.9% of prescriptions in the study population, respectively. Significant associations were found between QT-prolonging drug use and the factors of younger age and female gender. The most prevalent interaction was between citalopram and donepezil (2.7%), followed by the combination of escitalopram and donepezil (0.7%).

CONCLUSIONS

In this population of older people with major neurocognitive disorder, QT-prolonging drugs and interactions that increase the risk of torsade de pointes were prevalent. Due to the presence of many risk factors in this population, it is important to continuously evaluate current QT-prolonging drugs and concomitant drug treatment in each individual.

Drug-Associated QTc Prolongation in Geriatric Hospitalized Patients: A Cross-Sectional Study in Internal Medicine

Objective

The primary objectives of this prospective cross-sectional study were to estimate the prevalence of drug-related long QT syndrome (LQTS) and the prevalence of use of QT-prolonging drugs in older patients admitted to an internal medicine unit.

Methods

We screened consecutive patients hospitalized in an internal medicine unit over a 2-year period. A 12-lead electrocardiogram using an electrocardiograph with automated measurement of QT interval was recorded. Patient characteristics (age, sex, body mass index), drug treatments, and variables associated with QT interval prolongation, including hypothyroidism, type 2 diabetes mellitus, and cardiac disease, were also recorded. In addition, we also measured serum levels of potassium, calcium, magnesium, and creatinine at admission. The list of medications known to cause or to contribute to LQTS was obtained from CredibleMeds^®.

Results

A total of 243 patients were enrolled: mean ± standard deviation age, 79.65 ± 8.27 years; males, n = 121 (40.8%); mean corrected QT (QTc) interval, 453.70 ± 43.77 ms. Overall, 89/243 (36.6%) patients had a prolonged QTc interval, with 29/243 (11.9%) having QTc interval prolongation > 500 ms (11.9%). A vast majority were prescribed at least one QT-prolonging drug (218/243 [89.7%]), whereas 74/218 (30.5%) were receiving at least one medication with a known risk of Torsades des Pointes (TdP). Proton pump inhibitors were the second most commonly prescribed class of drugs. After logistic regression, male sex was independently associated with LQTS (odds ratio 2.85; 95% confidence interval 1.56–5.22; p = 0.001).

Conclusions

The prevalence of LQTS with QTc interval > 500 ms in geriatric inpatients was > 10%, and QT-prolonging drugs were frequently used on admission (more than 30% of patients were receiving drugs with a known risk of TdP).

Supplementary Information

The online version contains supplementary material available at 10.1007/s40801-021-00234-x.

Association of QTc Interval with Risk of Cardiovascular Diseases and Related Vascular Traits: A Prospective and Longitudinal Analysis

Background:

Prolonged heart rate corrected QT (QTc) interval was reported to be associated with cardiovascular diseases (CVDs).

Objective:

There exists little data on the association between QTc interval and cardiovascular risk in Asian populations. We prospectively investigated the association of QTc interval with CVDs and vascular traits in a large cohort of Chinese adults.

Methods:

A total of 7,605 participants aged 40 years or older from a well-defined community without CVDs at baseline were included and followed up for an average of 4.5 years. Association of baseline QTc interval with incident CVDs was evaluated using Cox regression analysis. Associations of QTc interval with brachial-ankle pulse wave velocity (baPWV), carotid intima-media thickness (CIMT), and risk of microalbuminuria and peripheral arterial diseases (PAD) were secondarily examined.

Results:

Prolonged QTc interval (≥460 ms in women and ≥450 ms in men) was associated with 51% higher risk of total major CVDs (hazard ratio [HR] = 1.51, 95% confidence interval [CI] [1.20, 1.90]), particularly, 48% increased risk of stroke (95% CI [1.16, 1.88]). Prolonged QTc interval was positively associated with baPWV (β = 38.10 cm/s, standard error [SE] = 8.04, P < 0.0001) and CIMT (β = 0.01 mm, SE = 0.01, P = 0.04). Prolonged QTc interval was associated with increased risk of incident microalbuminuria (odds ratio [OR] = 1.65, 95% CI [1.21, 2.24]) and PAD (2.49, 95% CI [1.35, 4.59]).

Conclusions:

Prolonged QTc interval is positively and significantly associated with increased risk of CVDs and related vascular traits in Chinese population.