Digoxin use and clinical outcomes in elderly Chinese patients with atrial fibrillation: a report from the Optimal Thromboprophylaxis in Elderly Chinese Patients with Atrial Fibrillation (ChiOTEAF) registry

Ventricular rate in atrial fibrillation and the risk of heart failure and death

AIMS

While clinical trials have suggested that a high ventricular rate is associated with increased risk of heart failure (HF) and mortality, all-comers studies are warranted.

OBJECTIVE

To assess 1-year risk of new-onset diagnosed HF and all-cause mortality among rate-control treated patients presenting with atrial fibrillation (AF) on an electrocardiogram (ECG) according to ventricular rate.

METHODS AND RESULTS

ECGs recorded at the Copenhagen General Practitioners Laboratory (2001-15) were used to identify patients with AF. Multivariate Cox proportional hazard regression models were used to compare risk of new-onset HF and all-cause mortality after first ECG presenting with AF according to ventricular rate on ECG [<60, 60-79, 80-99, and 100-110, > 110 beats per minute (bpm)]. We identified 7408 patients in treatment with rate control drugs at time of first ECG presenting with AF [median age 78 years (Q1,Q3 = 70-85 years)], 45.8% male, median ventricular rate 83 bpm, (Q1,Q3 = 71-101 bpm)]. During 1-year follow-up, 666 (9.0%) of all patients with AF developed HF and 858 (11.6%) died. Patients with AF ventricular rates 100-110 bpm and >110 bpm had a hazard ratio (HR) of 1.46 (CI: 1.10-1.95) and 2.41 (CI: 1.94-3.00) respectively for new-onset HF, compared with 60-79 bpm. Similarly, patients with AF ventricular rates 100-110 bpm and >110 bpm had a HR of 1.44 (CI: 1.13-1.82) and 1.34 (CI: 1.08-1.65) respectively for all-cause mortality, compared with 60-79 bpm.

CONCLUSIONS

Ventricular rates ≥100 bpm among patients presenting with AF on ECG in treatment with rate control drugs were associated with greater risk of both new-onset HF and all-cause mortality.

Impact of baseline blood pressure on all-cause mortality in patients with atrial fibrillation: results from a multicenter registry study

BACKGROUND

The ideal blood pressure (BP) target for patients with atrial fibrillation (AF) is still unclear. The present study aimed to assess the effect of the baseline BP on all-cause mortality in patients with AF.

METHODS

This registry study included 20 emergency centers across China and consecutively enrolled patients with AF from 2008 to 2011. All participants were followed for 1 year ± 1 month. The primary endpoint was all-cause mortality.

RESULTS

During the follow-up, 276 (13.9%) all-cause deaths occurred. Kaplan-Meier curves showed that a systolic blood pressure (SBP) ≤110 mmHg or >160 mmHg was associated with a higher risk of all-cause mortality (log-rank test, P  = 0.014), and a diastolic blood pressure (DBP) <70 mmHg was associated with the highest risk of all-cause mortality (log-rank test, P  = 0.002). After adjusting for confounders, the multivariable Cox regression model suggested that the risk of all-cause mortality was increased in the group with SBP ≤110 mmHg (hazard ratio [HR], 1.963; 95% confidence interval [CI], 1.306-2.951), and DBP <70 mmHg (HR, 1.628; 95% CI, 1.163-2.281). In the restricted cubic splines, relations between baseline SBP or DBP and all-cause mortality showed J-shaped associations (non-linear P <0.001 and P  = 0.010, respectively). The risk of all-cause mortality notably increased at a lower baseline SBP and DBP.

CONCLUSIONS

Having a baseline SBP ≤110 mmHg or DBP <70 mmHg was associated with a significantly higher risk of all-cause mortality in patients with AF. An excessively low BP may not be an optimal target for patients with AF.

Contemporary Trends in the Use of and Expenditures on Digoxin in the United States

BACKGROUND

Digoxin is indicated for the management of heart failure with reduced ejection fraction and atrial fibrillation. Despite stronger guideline recommendations for other pharmacologic and device therapies, digoxin retains a role in select patients unable to tolerate or refractory to standard therapies. Contemporary utilization of and costs related to digoxin in the United States of America (USA) remain uncharacterized. The objective of this study was to estimate trends in digoxin use and expenditures across the USA from 2010 to 2017.

METHODS

We utilized the Medical Expenditure Panel Survey to estimate trends in digoxin use and expenditures across the USA from 2010 to 2017. The Medical Expenditure Panel Survey is an overlapping panel survey that interviews households in the USA to ascertain their healthcare utilization and expenditures. Complex sampling procedures allow for nationally representative estimates of utilization and expenditures. We report the number of digoxin users and expenditures across key subgroups in 2-year increments from 2010 to 2017.

RESULTS

The number of digoxin users in the USA declined by 47% from 766 users per 100,000 adults in 2010-11 to 402 users per 100,000 adults in 2016-17. While digoxin use declined among women and self-identified White adults, adults living at or below the federal poverty level and those who self-identified as Asian or Hispanic represent an increasing proportion of overall digoxin users. While nationwide digoxin expenditures declined by 26% from 2010-11 to 2012-13, they peaked at $260.3 million in 2014-15 and remained elevated at $188.7 million in 2016-17.

CONCLUSIONS

Despite a nationwide trend towards declining use, digoxin remains prevalent amongst people of Asian and Hispanic descent in the USA. After a spike in cost in 2013, digoxin prices have yet to return to pre-spike levels. The role of digoxin in contemporary heart failure and arrhythmia management will continue to evolve as additional randomized and observational analyses become available.