+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Time outside of therapeutic range in atrial fibrillation patients is associated with long-term risk of dementia



Time outside of therapeutic range in atrial fibrillation patients is associated with long-term risk of dementia



Heart Rhythm 11(12): 2206-2213



The mechanisms behind the association of atrial fibrillation (AF) and dementia are unknown. One possibility is that exposure to chronic microembolism or microbleeds results in repetitive cerebral injury that is manifest by cognitive decline. The purpose of this study was to test the hypothesis that AF patients with a low percentage of time in the therapeutic range (TTR) are at higher risk for dementia due to under- or overanticoagulation. Patients anticoagulated with warfarin (target international normalized ratio [INR] 2-3), managed by the Intermountain Healthcare Clinical Pharmacist Anticoagulation Service with no history of dementia or stroke/transient ischemic attack, were included in the study. The primary outcome was dementia incidence defined by ICD-9 codes. Percent time in TTR was calculated using the method of linear interpolation and stratified as >75%, 51%-75%, 26%-50%, and ≤25%. Multivariable Cox hazard regression was used to determine dementia incidence by percentage categories of TTR. A total of 2605 patients (age 73.7 ± 10.8 years, 1408 [54.0%] male) were studied. The CHADS2 score distribution was 0: 216 (8.3%); 1: 579 (22.2%); 2: 859(33.0%); 3: 708 (27.2%); and ≥4: 243 (9.3%). The percent TTR averaged 63.1 ± 21.3, with percent INR <2.0: 25.6% ± 17.9% and percent INR >3.0: 16.2% ± 13.6%. Dementia was diagnosed in 109 patients (4.2%) (senile: 37 [1.4%]; vascular: 8 [0.3%]; Alzheimer: 64 (2.5%]). After adjustment, decreasing categories of percent TTR were associated with increased dementia risk (vs >75%): <25%: hazard ratio (HR) 5.34, P < .0001; 26%-50%: HR 4.10, P < .0001; and 51%-75%: HR = 2.57, P = .001. Quality of anticoagulation management represented as percent TTR among AF patients without dementia was associated with dementia incidence. These data support the possibility of chronic cerebral injury as a mechanism that underlies the association of AF and dementia.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 056584220

Download citation: RISBibTeXText

PMID: 25111326

DOI: 10.1016/j.hrthm.2014.08.013


Related references

Percent Time With a Supratherapeutic INR in Atrial Fibrillation Patients Also Using an Antiplatelet Agent Is Associated With Long-Term Risk of Dementia. Journal of Cardiovascular Electrophysiology 26(11): 1180-1186, 2015

Patients treated with catheter ablation for atrial fibrillation have long-term rates of death, stroke, and dementia similar to patients without atrial fibrillation. Journal of Cardiovascular Electrophysiology 22(8): 839-845, 2011

Major Outcomes in Atrial Fibrillation Patients with One Risk Factor: Impact of Time in Therapeutic Range Observations from the SPORTIF Trials. American Journal of Medicine 129(10): 1110-1116, 2016

Time in Therapeutic Range and Percentage of International Normalized Ratio in the Therapeutic Range as a Measure of Quality of Anticoagulation Control in Patients With Atrial Fibrillation. Canadian Journal of Cardiology 32(10): 1247.E23-1247.E28, 2016

Atrial fibrillation incrementally increases dementia risk across all CHADS 2 and CHA 2 DS 2 VASc strata in patients receiving long-term warfarin. American Heart Journal 188: 93-98, 2017

Use of neutrophil-lymphocyte ratio for risk stratification and relationship with time in therapeutic range in patients with nonvalvular atrial fibrillation: A pilot study. Clinical Cardiology 41(3): 339-342, 2018

Long-term Thromboembolic Risk in Patients With Postoperative Atrial Fibrillation After Coronary Artery Bypass Graft Surgery and Patients With Nonvalvular Atrial Fibrillation. JAMA Cardiology 3(5): 417-424, 2018

Ablation of atrial fibrillation at the time of cavotricuspid isthmus ablation in patients with atrial flutter without documented atrial fibrillation derives a better long-term benefit. Journal of Cardiovascular Electrophysiology 22(1): 34-38, 2011

Newly developed post-operative atrial fibrillation is associated with an increased risk of late recurrence of atrial fibrillation in patients who underwent open heart surgery: Long-term follow up. Cardiology Journal 24(6): 633-641, 2017

Age is associated with time in therapeutic range for warfarin therapy in patients with atrial fibrillation. Oncotarget 7(34): 54194-54199, 2016

Time in therapeutic range and major adverse outcomes in atrial fibrillation patients undergoing percutaneous coronary intervention: The Atrial Fibrillation Undergoing Coronary Artery Stenting (AFCAS) registry. American Heart Journal 190: 86-93, 2017

Atrial Fibrillation Patients Treated With Long-Term Warfarin Anticoagulation Have Higher Rates of All Dementia Types Compared With Patients Receiving Long-Term Warfarin for Other Indications. Journal of the American Heart Association 5(7):, 2016

Patients' time in therapeutic range on warfarin among US patients with atrial fibrillation: Results from ORBIT-AF registry. American Heart Journal 170(1): 141-8 148.E1, 2015

Relation Of The Time In Therapeutic Range (Ttr) Of Warfarin To Bleeding Incidences In Patients With Atrial Fibrillation. Value in Health 17(7): A478, 2014

SAMe-TT2R2 score, time in therapeutic range, and outcomes in anticoagulated patients with atrial fibrillation. American Journal of Medicine 127(11): 1083-1088, 2014