Atrial fibrillation in myocardial infarction patients: Impact on health care utilization

Addressing Multimorbidity and Polypharmacy in Individuals With Atrial Fibrillation

PURPOSE OF REVIEW

The objectives of this review were to (1) discuss how multimorbidity and polypharmacy contributes to the complexity of management among individuals with AF and (2) identify any interventions to manage polypharmacy in relation to AF.

RECENT FINDINGS

Based on the four landmark clinical trials of novel anticoagulants, the most common comorbidities with AF are hypertension, heart failure, diabetes, stroke and myocardial infarction. Polypharmacy was also found prevalent in 76.5% of patients with AF, with a median of six drugs per patient. Despite the consequences of polypharmacy in AF, there is very little evidence-based intervention designed to manage it. Hence, there is a need for further research to examine interventions to manage polypharmacy in relation to AF. Atrial fibrillation (AF) is the most common type of cardiac arrhythmia requiring treatment in adults. Due to the structural and/or electrophysiological abnormalities that occur in AF, patients are managed through the use of prophylactic anticoagulant and rate and/or rhythm control medications. However, these medications are considered high risk and can increase the chances of medication misadventure. Additionally, AF rarely occurs in isolation and is known to coexist with multiple other medical comorbidities, i.e. multimorbidity. This also increases the number of medications, i.e. polypharmacy and pill burden which results in treatment non-compliance to prescribed therapy.

High-sensitivity troponin and novel biomarkers for the early diagnosis of non-ST-segment elevation myocardial infarction in patients with atrial fibrillation

AIMS

To evaluate the diagnostic performance of high-sensitivity troponin I (hsTnI) and other novel biomarkers for diagnosing non-ST-segment elevation myocardial infarction (NSTEMI) in patients with atrial fibrillation.

METHODS

In an acute chest pain cohort (N=1673), mean age 61.4±13.6 (34% female), we measured hsTnI and 13 established and novel biomarkers reflecting ischaemia, necrosis, inflammation, myocardial stress, angiogenesis on admission and after three hours in order to investigate their diagnostic accuracy for NSTEMI.

RESULTS

In atrial fibrillation patients (N=299) hsTnI on admission had the best discriminatory ability for NSTEMI (area under the curve 0.97) with only two novel biomarkers, copeptin and heart-type fatty acid binding protein, having area under the curve >0.70. Measured biomarkers showed comparable discriminatory ability in atrial fibrillation and non-atrial fibrillation patients. The combination of hsTnI on admission with additional biomarkers did not clinically significantly improve diagnostic performance. In atrial fibrillation patients, hsTnI concentrations ⩽21.7 ng/L (99th percentile in a healthy German cohort) on admission gave a negative predictive value of ~100% (95% confidence interval 97-100%). The combination of hsTnI on admission and absolute change of hsTnI concentration after three hours of ⩾40 ng/L resulted in a positive predictive value of 81.2% and sensitivity of 88.6%. Diagnostic accuracy was validated in an independent cohort (N=1076).

CONCLUSION

The diagnostic accuracy of hsTnI in patients with acute chest pain and atrial fibrillation is high and comparable to those without atrial fibrillation. Absolute change in hsTnI concentration enhanced diagnostic performance. No clinically relevant improvement was achieved by adding other biomarkers.

Association Between Atrial Fibrillation and Costs After Myocardial Infarction: A Community Study

BACKGROUND

The authors sought to estimate incremental economic impact of atrial fibrillation (AF) and the timing of its onset in myocardial infarction (MI) patients.

HYPOTHESIS

Concurrent AF and its timing are associated with higher costs in MI patients.

METHODS

This retrospective cohort study included incident MI patients from Olmsted County, Minnesota, treated between November 1, 2002, and December 31, 2010. We compared inflation-adjusted standardized costs accumulated between incident MI and end of follow-up among 3 groups by AF status and timing: no AF, new-onset AF (within 30 days after index MI), and prior AF. Multivariate adjustment of median costs accounted for right-censoring in costs.

RESULTS

The final study cohort had 1389 patients, with 989 in no AF, 163 in new-onset AF, and 237 in prior AF categories. Median follow-up times were 3.98, 3.23, and 2.55 years, respectively. Mean age at index was 67 years, with significantly younger patients in the no AF group (64 years vs 76 and 77 years, respectively; P < 0.001). New-onset and prior AF patients had more comorbid conditions (hypertension, heart failure, and chronic obstructive pulmonary disease). After accounting for differences in baseline characteristics, we found adjusted median (95% confidence interval) costs of $73 000 ($69 000-$76 000) for no AF; $85 000 ($81 000-$89 000) for new-onset AF; and $97 000 ($94 000-$100 000) for prior AF. Inpatient costs composed the largest share of total median costs (no AF, 82%; new-onset AF, 84%; prior AF, 83%).

CONCLUSIONS

Atrial fibrillation frequently coexists with MI and imposes incremental costs, mainly attributable to inpatient care. Timing of AF matters, as prior AF was found to be associated with higher costs than new-onset AF.