When to withhold oral anticoagulation in atrial fibrillation - an overview of frequent clinical discussion topics

Direct Oral Anticoagulants in Older and Frail Patients with Atrial Fibrillation: A Decade of Experience

INTRODUCTION

Both the prevalence of atrial fibrillation (AF) and its subsequent use of direct oral anticoagulants (DOACs) are rapidly increasing in patients of older age. In the absence of contra-indications, guidelines advocate anticoagulation based on the CHA2DS2-VASc score for all AF patients aged 75 and above. However, some practitioners are hesitant to prescribe anticoagulants to older and frail patients due to perceived elevated bleeding risks. This review delves into the comparative treatment outcomes of DOACs versus vitamin K antagonists (VKAs) in older patients with AF, particularly focusing on those of advanced age, frailty, increased risk of falling, chronic kidney disease (CKD), or with a history of major bleeding. Additionally, considerations on the use of off-label DOAC doses, the role of left atrial appendage (LAA) closure and future developments in factor XIa-inhibitors will be discussed.

RESULTS

While strong evidence supports the use of DOACs in the vital older patients with nonvalvular AF, it remains scant in frail patient groups. There is some evidence from non-randomized studies suggesting that the effect of DOACs compared with VKAs is consistent between frail and nonfrail patients. However, recent findings from a single randomized trial showed increased bleeding risks but comparable thromboembolic outcomes in frail individuals switching from VKAs to DOACs. In patients with an increased risk of falling, data suggest no relevant interaction of increased risk of falling on the effectiveness and safety of DOACs compared with warfarin. Resuming oral anticoagulants in patients with Af after major bleeding seems to be beneficial. Off-label low-dose DOAC is often prescribed to patients who were underrepresented in larger randomized trails because of an elevated risk of bleeding or overexposure to DOACs, but its effect on clinical outcomes remains uncertain.

CONCLUSIONS

DOACs are the recommended oral anticoagulant for vital older patients with AF. The scarcity of data backing DOAC use in frail individuals, those with renal impairments, or significant bleeding history underscores the necessity for further investigation. However, existing evidence suggests at least similar effectiveness and safety and potential benefits for DOACs in these patient subsets. Therefore, there is no reason to suggest these patients should be treated differently than the established guidelines regarding anticoagulation.

Anticoagulation in embolic acute limb ischaemia-an observational study

The management of embolic acute limb ischaemia commonly involves determining aetiology and performing emergency invasive procedures. This detailed study aimed to determine the impact of manipulation of anticoagulation in the aetiology of emboli in acute limb ischaemia and determine the efficacy of primary anticoagulation therapy vs. invasive interventions. Material and methods: Data collection was conducted at a single institution on a cohort of patients presenting consecutively with embolic acute limb ischaemia over one year. Two groups were compared, one receiving anticoagulation as primary therapy with those undergoing invasive treatment as the internal comparison group. Results: A likely haematological causation was identified in 22 of 38 presentations, related to interruption of anticoagulation in cardiac conditions, the majority atrial fibrillation (n=12), or hypercoagulable states (n=10). Limb salvage was pursued in 36 patients employing anticoagulation (n=19) or surgical embolectomy (n=17) as the primary therapy in upper and lower limbs (n=17 vs n=19 respectively). Despite delays often well beyond six hours and a range of ischaemic severity in both groups, 35 of 36 patients achieved full or substantive restoration of function with improved perfusion. Regarding anatomical distribution of arterial disease and therapy, three patients with multi-level disease proceeded to embolectomy following anticoagulation. Embolectomy was undertaken most often for proximal emboli and more profound paralysis. Conclusions: Anticoagulation and coagulopathy are commonly implicated in the aetiology of arterial emboli, with omission of effective anticoagulation in atrial fibrillation being associated in almost 1/3 of presentations. Whilst more profound limb paralysis and proximal or multi-level disease tended to be managed surgically, primary anticoagulation therapy alone or with a secondary embolectomy was effective across the spectrum of ischaemia severity and despite significant delays beyond guideline recommendations.

Intracerebral hemorrhage mortality in individuals with atrial fibrillation: a nationwide analysis of mortality trends in the United States

BACKGROUND

Atrial fibrillation (AF) is a risk factor for intracerebral hemorrhage (ICH), both with and without use of anticoagulation. Limited data exists on mortality trends and disparities related to this phenomenon. We aimed to assess ICH mortality trends and disparities based on demographic factors in individuals with atrial fibrillation in the United States (US).

METHODS

Our cross-sectional analysis utilized mortality data from the CDC database through death certificate queries from the years 1999 to 2020 in the US. We queried for all deaths with ICH as the underlying cause of death and atrial fibrillation as the multiple causes of death. Mortality data was obtained for overall population and demographic subpopulations based on sex, race and ethnicity, and geographic region. Trend analysis and average annual-mortality percentage change (AAPC) were completed using log-linear regression models.

RESULTS

ICH age-adjusted mortality rate (AAMR) in patients with AF increased from 0.27 (95% CI 0.25-0.29) in 1999 to 0.30 (95% CI 0.29-0.32) in 2020. A higher mortality rate was observed in males (AAMR 0.33) than in females (AAMR 0.26). The highest mortality was found in Asian/Pacific Islander (AAMR: 0.32) populations, followed by White (AAMR: 0.30), Black (AAMR: 0.15), and American Indian/Alaska Native (AAMR: 0.11) populations. Southern (AAPC: 1.3%) and non-metropolitan US regions (AAPC: + 1.9%) had the highest increase in annual mortality change.

CONCLUSION

Our findings highlight the disparities in ICH mortality in patients with AF. Further investigation is warranted to confirm these findings and evaluate for contributors to the observed disparities.

Benefit and risk of oral anticoagulant initiation strategies in patients with atrial fibrillation and cancer: a target trial emulation using the SEER-Medicare database

Oral anticoagulants (OACs) are recommended for patients with atrial fibrillation (AFib) having CHA2DS2-VASc score ≥ 2. However, the benefits of OAC initiation in patients with AFib and cancer at different levels of CHA2DS2-VASc is unknown. We included patients with new AFib diagnosis and a record of cancer (breast, prostate, or lung) from the 2012-2019 Surveillance, Epidemiology, and End Results (SEER)-Medicare database (n = 39,915). Risks of stroke and bleeding were compared between 5 treatment strategies: (1) initiated OAC when CHA2DS2-VASc ≥ 1 (n = 6008), (2) CHA2DS2-VASc ≥ 2 (n = 8694), (3) CHA2DS2-VASc ≥ 4 (n = 20,286), (4) CHA2DS2-VASc ≥ 6 (n = 30,944), and (5) never initiated OAC (reference group, n = 33,907). Confounders were adjusted using inverse probability weighting through cloning-censoring-weighting approach. Weighted pooled logistic regressions were used to estimate treatment effect [hazard ratios (HRs) and 95% confidence interval (95% CIs)]. We found that only patients who initiated OACs at CHA2DS2-VASc ≥ 6 had lower risk of stroke compared without OAC initiation (HR 0.64, 95% CI 0.54-0.75). All 4 active treatment strategies had reduced risk of bleeding compared to non-initiators, with OAC initiation at CHA2DS2-VASc ≥ 6 being the most beneficial strategy (HR = 0.49, 95% CI 0.44-0.55). In patients with lung cancer or regional/metastatic cancer, OAC initiation at any CHA2DS2-VASc level increased risk of stroke and did not reduce risk of bleeding (except for Regimen 4). In conclusion, among cancer patients with new AFib diagnosis, OAC initiation at higher risk of stroke (CHA2DS2-VASc score ≥ 6) is more beneficial in preventing ischemic stroke and bleeding. Patients with advanced cancer or low life-expectancy may initiate OACs when CHA2DS2-VASc score ≥ 6.

Thromboembolic and bleeding complications during interruptions and after discontinuation of anticoagulant treatment in patients with atrial fibrillation and active cancer: A daily practice evaluation

BACKGROUND AND AIMS

Cancer provides challenges to the continuity of anticoagulant treatment in patients with atrial fibrillation (AF), e.g. through cancer-related surgery or complications. We aimed to provide data on the incidence and reasons for interrupting and discontinuing anticoagulant treatment in AF patients with cancer and to assess its contribution to the risk of thromboembolism (TE) and major bleeding (MB).

METHODS

This retrospective study identified AF patients with cancer in two hospitals between 2012 and 2017. Data on anticoagulant treatment, TE and MB were collected during two-year follow-up. Incidence rates (IR) per 100 patient-years and adjusted hazard ratios (aHR) were obtained for TE and MB occurring during on- and off-anticoagulant treatment, during interruption and after resumption, and after permanent discontinuation.

RESULTS

1213 AF patients with cancer were identified, of which 140 patients permanently discontinued anticoagulants and 426 patients experienced one or more interruptions. Anticoagulation was most often interrupted or discontinued due to cancer-related treatment (n = 441, 62 %), bleeding (n = 129, 18 %) or end of life (n = 36, 5 %). The risk of TE was highest off-anticoagulation and during interruptions, with IRs of 19 (14-25)) and 105 (64-13), and aHRs of 3.1 (1.9-5.0) and 4.6 (2.4-9.0), respectively. Major bleeding risk were not only increased during an interruption, but also in the first 30 days after resumption, with IRs of 33 (12-72) and 30 (17-48), and aHRs of 3.3 (1.1-9.8) and 2.4 (1.2-4.6), respectively.

CONCLUSIONS

Interruption of anticoagulation therapy harbors high TE and MB risk in AF patients with cancer. The high incidence rates call for better (periprocedural) anticoagulant management strategies tailored to the cancer setting.

[Anticoagulation in older patients]

Prescribing oral anticoagulation in older patients for e.g. stroke prophylaxis has proven to be beneficial, but some special risks have to be considered. Renal function may be substantial impaired and dose reduction in at least some of the substances is recommended. Therefore, a closer monitoring of renal function is essential. Further as bleeding risk also increases with age usual scoring lists do less help this therapeutic dilemma than in younger patients. Adequate blood pressure control is essential in preventing intracerebral hemorrhage. Fall risk has to be assessed to initiate early compensation for this risk. Only high and unimprovable fall incidence may outweigh the benefits of oral anticoagulation therapy (>1 hospital admission per month due to a fall incident). Comprehensive geriatric assessment is crucial for early detection of specific adherence problems in older patients and is also helpful for discussion of individual deprescribing options in an end of live situation.

Anticoagulant Treatment in Patients with AF and Very High Thromboembolic Risk in the Era before and after the Introduction of NOAC: Observation at a Polish Reference Centre

Atrial fibrillation (AF) is associated with an increased risk of stroke. Therefore, patients with AF require appropriate management and anticoagulant therapy. To balance therapy risks and benefits, oral anticoagulants (OAC) treatment should be 'tailored' in patients at a high risk of stroke and bleeding. However, some studies have demonstrated that certain groups of patients do not receive anticoagulants despite the high risk of stroke or thromboembolism. The study aimed to analyse therapeutic methods of stroke prevention in very high-risk patients (CHA2DS2-VASc score of ≥5 in men and ≥6 in women), identify factors predisposing against the use of OACs and assess the administration of anticoagulants before the introduction of non-vitamin K antagonist OAC (NOAC) in 2004-2011 and beyond (years 2012-2019). The analysis covered 2441 patients with AF at a very high thromboembolic risk who were hospitalised in a reference cardiological centre from 2004 to 2019. Data concerning patients' sex, age, comorbidities, type of AF, renal and echocardiographic parameters, reasons for hospitalisation and applied treatment were collected from medical records. HAS-BLED, CHADS2, and CHA2DS2-VASc scores were calculated for all patients. The treatment with oral anticoagulants was compared in the entire population over 2004-2011 and 2012-2019. In this study, a fifth of patients were not treated with OAC. Most patients hospitalised in the years 2012-2019 were treated with OAC. The predictors of not using OAC turned out to be: age of >74 years, heart failure, cancer, paroxysmal AF, and acute coronary syndrome (ACS) or elective coronary angiography/percutaneous coronary intervention (PCI) as a reason for hospitalisation. The introduction of NOAC was associated with a decline in the use of VKA (from 62% to 19.1%) and APT (from 29.1% to 1.3%). This study outlines reasons to initiate OAC treatment in very high-risk patients in clinical practice.

Effects of the ABC pathway on clinical outcomes in a secondary prevention population of Chinese patients with atrial fibrillation: A report from the Optimal Thromboprophylaxis in Elderly Chinese Patients with Atrial Fibrillation (ChiOTEAF) registry

Background

The atrial fibrillation better care (ABC) pathway is a simple, comprehensive framework that facilitates provision of integrated care for atrial fibrillation (AF) patients.

Objective

We evaluated management of AF patients in a secondary prevention cohort using the ABC pathway and examined the impact of ABC adherence on clinical outcomes.

Methods

The Chinese Patients with Atrial Fibrillation registry is a prospective registry conducted in 44 sites across China between October 2014 and December 2018. The primary outcome was the composite of all-cause mortality/any thromboembolism (TE), all-cause death, any TE and major bleeding at 1 year.

Results

Of the 6420 patients, 1588 (24.7%) had a prior stroke or transient ischemic attack and were identified as the secondary prevention cohort. After excluding 793 patients due to insufficient data, 358 (22.5%) were ABC compliant and 437 (27.5%) ABC noncompliant. ABC adherence was associated with a significantly lower risk of the composite outcome of all-cause death/TE, odds ratio (OR) 0.28 (95% confidence interval [CI]: 0.11-0.71) and all-cause death, OR 0.29 (95% CI: 0.09-0.90). Significant differences were not observed for TE, OR 0.27 (95% CI: 0.06-1.27) and major bleeding, OR 2.09 (95% CI: 0.55-7.97). Age and prior major bleeding were significant predictors of ABC noncompliance. Health-related quality of life (QOL) was higher in the ABC compliant group versus the noncompliant group (EQ score 0.83 ± 0.17 vs. 0.78 ± 0.20; p = .004).

Conclusion

ABC pathway adherence in secondary prevention AF patients was associated with a significantly lower risk of the composite outcome of all-cause death/TE and all-cause death, as well as better health-related QOL.

Embolic Cerebrovascular Accident Secondary to Device-Related Thrombus Post WATCHMAN Device Implantation

Atrial fibrillation (AF) is one of the most common cardiac arrhythmias encountered. Aggressive and appropriate management, along with identification and modification of risk factors, remains at the forefront of evidence-based practice. Thrombus formation (primarily in the left atrial appendage) and consequent thromboembolism are risks associated with AF. Anticoagulation is utilized to prevent and reduce AF-induced complications such as stroke, heart failure, and death. However, in instances when the risk of bleeding from anticoagulation outweighs the benefits of stroke prevention, other modalities such as left atrial appendage closure (LAAC) devices like the WATCHMAN device (Boston Scientific, MA) are utilized. LAAC devices, such as the WATCHMAN device, are also not without significant risks, one of them being device-related thrombus (DRT) formation. We present a case of device-related thrombus formation post WATCHMAN implantation and a subsequent embolic cerebrovascular accident (CVA).

Thrombotic events and rebleeding after hemorrhage in patients taking direct oral anticoagulants for non-valvular atrial fibrillation

Several direct oral anticoagulants have been developed to prevent cardiogenic thrombosis in patients with atrial fibrillation, on the other hand, have the complication of bleeding. Since clinical course after bleeding with direct oral anticoagulant remains unclear, the present retrospective cohort study was to clarify the course after hemorrhage among patients receiving direct oral anticoagulants. Among all 2005 patients prescribed dabigatran, rivaroxaban, apixaban, or edoxaban between April 2011 and June 2017, subjects comprised 96 patients with non-valvular atrial fibrillation who experienced relevant bleeding during direct oral anticoagulant therapy (Bleeding Academic Research Consortium type 2 or above). The clinical course after hemorrhage was reviewed to examine whether rebleeding or thrombotic events occurred up to the end of December 2019. Gastrointestinal bleeding was the most frequent cause of initial bleeding (57 patients, 59%). Rebleeding occurred in 11 patients (4.5%/year), with gastrointestinal bleeding in 10 and subarachnoid hemorrhage in 1. All rebleeding occurred in patients who resumed anticoagulation therapy. Another significant factor related with rebleeding included past history of gastrointestinal bleeding. On the other hand, major adverse cardiac and cerebrovascular events occurred in 6 patients older than 75 years old or more (2.5%/year), with systemic thrombosis in 4 and cardiac death in 2. All 4 patients with systemic thrombosis withheld anticoagulants after index bleeding, although only 10 patients withheld anticoagulation therapy. Rebleeding should be taken care of when anticoagulants are resumed after bleeding, particularly among patients who initially experienced gastrointestinal bleeding. Systemic thrombosis occurred at a high rate when anticoagulant therapy was withheld after bleeding.

Echocardiographic predictors of cardioembolic stroke due to underlying atrial fibrillation: Reliable left atrial remodeling signs in acute stroke

INTRODUCTION

Atrial remodeling due to high-burden atrial fibrillation (AF) is associated with cardioembolic stroke (CES). As not all CESs is caused by AF, we analyzed the diagnostic values of each echocardiographic parameter to distinguish likely AF-related CES in acute stroke patients while in non-AF rhythm.

METHODS

The data of consecutive patients with acute ischemic stroke in sinus rhythm between 2012 and 2015 were obtained. The echocardiographic parameters of patients with CES due to underlying AF (n = 61) and control patients (n = 319) with either large artery atherosclerosis or small-vessel occlusion were compared using receiver operating characteristic curves and logistic regression analyses. Each parameter was reassessed in acute stroke patients through a validation study using the same database with different periods of generalization.

RESULTS

CES patients with underlying AF showed a significantly larger left atrial volume index (LAVi), higher mitral inflow E wave (E), and lower A wave (A) than the controls. The area under the curve (AUC) (95% confidence interval) for diagnosing CES due to underlying AF was significantly higher for LAVi/A than for LAVi (0.785 versus 0.696, P < 0.01). Among patients aged >60 years, the E/A ratio had the highest AUC (0.857) of the parameters. The cut-off values were ≥ 0.70 (sensitivity, 55.7%; specificity, 90.9%) and ≥ 0.82 (sensitivity, 71.4%; specificity, 84.1%) for LAVi/A and the E/A ratio, respectively, in patients >60 years. The cut-off values of all parameters showed similar trends in a validation study.

CONCLUSION

LAVi/A is a useful indicator for distinguishing CES patients with underlying AF regardless of age, and the E/A ratio is reliable among patients aged >60 years in evaluation during acute stroke admission.

CHA2DS2-VASc and HAS-BLED risk scores and real-world oral anticoagulant prescribing decisions in atrial fibrillation

Background: Guidelines indicate that oral anticoagulant (OAC) treatment decisions in atrial fibrillation should be based on a balanced consideration of thromboembolic and bleeding risk. Materials & methods: A retrospective cohort of nonvalvular atrial fibrillation patients were identified. Univariate logistic regression and conditional inference trees were used to quantify the importance of the CHA₂DS₂-VASc and modified HAS-BLED scores and their individual components on OAC treatment decisions. Results: The individual components of these risk scores provided more distinguishability between treated and untreated patients than the risk scores themselves, with bleeding risk factors strongly associated with nontreatment. Conclusion: While individual components of risk scores drive OAC treatment decisions according to guidelines, the relationship between bleeding risk factors and nontreatment warrants further consideration.

Adherence to anticoagulant guideline for atrial fibrillation: A large care gap among stroke patients in a rural population

OBJECTIVE

This study aimed to investigate the prevalence and factors associated with oral anticoagulant undertreatment of atrial fibrillation (AF) among a cohort of rural patients with stroke outcomes and examine how undertreatment may influence a patient's one-year survival after stroke.

METHODS

This retrospective cohort study examined ischemic stroke patients with pre-stroke AF diagnosis from September 2003 to May 2019 and divided them into proper treatment and undertreatment group. Analysis included chi-square test, variance analysis, Kruskal-Wallis test, logistic regression, Kaplan-Meier estimator, and Cox proportional-hazards model.

RESULTS

Out of 1062 ischemic stroke patients with a pre-stroke AF diagnosis, 1015 patients had a CHA₂DS₂-VASc score ≥2, and 532 (52.4%) of those were undertreated. Median time from AF diagnosis to index stroke was significantly lower among undertreated patients (1.9 years vs. 3.6 years, p < 0.001). Other thromboembolism, excluding stroke, TIA, and myocardial infarction (OR 0.41, p < 0.001), the number of encounters per year (OR 0.90, p < 0.001), and the median time between AF diagnosis and stroke event (OR 0.86, p < 0.001) were negatively associated with undertreatment. Kaplan-Meier estimator showed no statistical difference in the one-year survival probability between groups (log-rank test, p = 0.29), while the Cox-Hazard model showed that age (HR 1.05, p < 0.001) and history of congestive heart failure (HR 1.88, p < 0.001) increased the risk of mortality.

CONCLUSIONS

More than half of our rural stroke patients with a pre-index AF diagnosis were not on guideline-recommended treatment. The study highlights a large care gap and an opportunity to improve AF management.

Antithrombotic Strategies in Invasively Managed Patients with Non-ST Elevation Acute Coronary Syndromes and Non-Valvular Atrial Fibrillation in Romania

Introduction: Concomitant atrial fibrillation (AF) in non-ST segment elevation acute coronary syndrome (NSTE-ACS) patients complicates the decision-making process regarding short- and long-term antithrombotic strategies. Patient profiles and usage rates of different antithrombotic combinations in this patient subgroup in Romania are poorly described. Premises and objectives: To describe the characteristics of invasively managed NSTE-ACS patients with AF (either known or newly diagnosed) compared to patients with no oral anticoagulation (OAC) indications, and analyze the rates and factors that influence the different antithrombotic regimens at discharge in AF patients. Material and methods: The Romanian National NSTE-ACS Registry allows the enrollment of invasively managed NSTE-ACS patients admitted in 11 interventional centers. Patients with non-valvular AF and no other OAC indication were identified and compared with patients with no indication for OAC. The antithrombotic strategy at discharge was analyzed based on demographic, clinical, and invasive management characteristics. Outcomes:A total of 1418 patients were enrolled between 2016 and 2019 out of which, 175 AF subjects and 1159 patients with no OAC indication were included in the analysis. Subjects with AF were older (70 ± 8.3 vs 62.9 ± 10.4 years, p <0.001) and more likely to have a GRACE score >140 (aOR 2.28, 95% CI 1.58-3.31, p<0.001), a history of heart failure (aOR 3.07, 95% CI 2.14-4.41, p <0.001), dementia or Alzheimer disease (aOR 3.45, 95% CI 1.11-10.68, p 0.032), and non-fatal major cardiovascular (CV) events during admission (aOR 6.71, 95% CI 1.61-27.94, p 0.009). Globally, triple antithrombotic therapy (TAT) was used in 52.5% of AF patients. 69% of PCI patients received TAT. One in four patients with AF did not receive OAC at discharge. Prior treatment with OAC was the strongest predictor for OAC usage at discharge (aOR 12.34, 95% CI 3.21-47.61, p<0.001). Conclusion: More than one in 10 NSTE-ACS patients have a concomitant non-valvular AF diagnosis. These patients are significantly older and are more likely to have significant CV and non-CV disease. Triple antithrombotic therapy is the most used antithrombotic strategy, especially in the PCI subgroup. One in four NSTE-ACS AF patients do not receive OAC at discharge.

Management of Atrial Fibrillation in Older Patients by Morbidity Burden: Insights From Get With The Guidelines-Atrial Fibrillation

Background Knowledge is scarce regarding how multimorbidity is associated with therapeutic decisions regarding oral anticoagulants (OACs) in patients with atrial fibrillation. Methods and Results We conducted a cross-sectional study of hospitalized patients with atrial fibrillation using the Get With The Guidelines-Atrial Fibrillation registry from 2013 to 2019. We identified patients ≥65 years and eligible for OAC therapy. Using 16 available comorbidity categories, patients were stratified by morbidity burden. A multivariable logistic regression model was used to determine the odds of receiving OAC prescription at discharge by morbidity burden. We included 34 174 patients with a median (interquartile range) age of 76 (71-83) years, 56.6% women, and 41.9% were not anticoagulated at admission. Of these patients, 38.6% had 0 to 2 comorbidities, 50.7% had 3 to 5 comorbidities, and 10.7% had ≥6 comorbidities. The overall discharge OAC prescription was high (85.6%). The prevalence of patients with multimorbidity increased from 59.7% in 2014 to 64.3% in 2019 (P trend=0.002). Using 0 to 2 comorbidities as the reference, the adjusted odds ratio (95% CI) of OAC prescription were 0.93 (0.82, 1.05) for patients with 3 to 5 comorbidities and 0.72 (0.60, 0.86) for patients with ≥6 comorbidities. In those with ≥6 comorbidities, the most common reason for nonprescription of OACs were frequent falls/frailty (31.0%). Conclusions In a contemporary quality-of-care database of hospitalized patients with atrial fibrillation eligible for OAC therapy, multimorbidity was common. A higher morbidity burden was associated with a lower odds of OAC prescription. This highlights the need for interventions to improve adherence to guideline-recommended anticoagulation in multimorbid patients with atrial fibrillation.