Administration, Oral ; Anticoagulants/adverse effects* ; Atrial Fibrillation/drug therapy* ; Humans ; Stroke ; Vascular Calcification/drug therapy* ; Warfarin

BACKGROUNDWarfarin is the most common oral anticoagulant to decrease the stroke risk associated with atrial fibrillation (AF). There are very few prospective studies that have explored whether warfarin has an association with damage on renal function in Chinese patients with nonvalvular AF (NVAF). The aim of this study was to evaluate the effects of warfarin on renal function and study the factors associated with kidney dysfunction in Chinese adult NVAF patients without dialysis therapy.

METHODSFrom January 2011 to December 2013, a total of 951 NVAF patients from 18 hospitals were enrolled. The estimated glomerular filtration rate (eGFR) was calculated from baseline and follow-up serum creatinine levels. Kaplan-Meier survival curves compared the survival of a ≥25% decline in eGFR (hereafter, endpoint), while Cox models estimated hazard ratios (HR s) and 95% confidence intervals for this event after adjustment for age, gender, and selected potential risk factors for renal dysfunction. Cox regression analysis of the various clinical potential variables was performed to identify the predictors of a ≥25% decline in eGFR.

RESULTSAfter a 58-month follow-up, 951 NVAF patients were divided by observation into warfarin (n = 655) and no anticoagulation groups (n = 296) and 120 (12.6%) patients experienced renal endpoint. Kaplan-Meier survival curves showed that the survival period was not different in the two groups (χ2 = 0.178, log-rank P= 0.67), but patients with systolic blood pressure (SBP) <140 mmHg have significant difference with patients with SBP ≥140 mmHg (χ2 = 4.903, log-rank P= 0.03). Multivariate Cox regression analysis revealed baseline eGFR and SBP as independent predictors of the endpoint, with HR s of 1.00, and 1.02, respectively.

CONCLUSIONIn patients with NVAF, eGFR and SBP are associated with the deterioration of kidney function while Warfarin is not the risk factor of the ≥25% decline in eGFR.

TRIAL REGISTRATIONChinese Clinical Trial Registry (No. ChiCTR-OCH-13003729); http://www.chictr.org.cn/showproj.aspx?proj = 5831.

Aged ; Anticoagulants ; adverse effects ; therapeutic use ; Atrial Fibrillation ; drug therapy ; physiopathology ; Female ; Glomerular Filtration Rate ; physiology ; Humans ; Kaplan-Meier Estimate ; Kidney ; drug effects ; Male ; Middle Aged ; Prospective Studies ; Warfarin ; adverse effects ; therapeutic use

In traditional Chinese medicine (TCM), the human body is divided into Yin and Yang. Diseases occur when the Yin and Yang balance is disrupted. Different herbs are used to restore this balance, achieving the goal of treatment. However, inherent difficulties in designing experimental trials have left much of TCM yet to be substantiated by science. Despite that, TCM not only remains a popular form of medical treatment among the Chinese, but is also gaining popularity in the West. This phenomenon has brought along with it increasing reports on herb-drug interactions, beckoning the attention of Western physicians, who will find it increasingly difficult to ignore the impact of TCM on Western therapies. This paper aims to facilitate the education of Western physicians on common Chinese herbs and raise awareness about potential interactions between these herbs and warfarin, a drug that is especially susceptible to herb-drug interactions due to its narrow therapeutic range.
Animals ; Carthamus tinctorius ; chemistry ; Clinical Trials as Topic ; Drugs, Chinese Herbal ; administration & dosage ; adverse effects ; therapeutic use ; Ginger ; chemistry ; Ginkgo biloba ; chemistry ; Glycyrrhiza ; chemistry ; Herb-Drug Interactions ; Humans ; Lycium ; chemistry ; Medicine, Chinese Traditional ; methods ; Panax ; chemistry ; Prunus persica ; chemistry ; Salvia miltiorrhiza ; chemistry ; Singapore ; Warfarin ; administration & dosage ; adverse effects ; therapeutic use

Chemical and Drug Induced Liver Injury ; pathology ; Hepatitis, Autoimmune ; pathology ; Humans ; Warfarin ; adverse effects

PURPOSE: In this study, we investigated the stroke mechanism and the factors associated with ischemic stroke in patients with nonvalvular atrial fibrillation (NVAF) who were on optimal oral anticoagulation with warfarin. MATERIALS AND METHODS: This was a multicenter case-control study. The cases were consecutive patients with NVAF who developed cerebral infarction or transient ischemic attack (TIA) while on warfarin therapy with an international normalized ratio (INR) > or =2 between January 2007 and December 2011. The controls were patients with NVAF without ischemic stroke who were on warfarin therapy for more than 1 year with a mean INR > or =2 during the same time period. We also determined etiologic mechanisms of stroke in cases. RESULTS: Among 3569 consecutive patients with cerebral infarction or TIA who had NVAF, 55 (1.5%) patients had INR > or =2 at admission. The most common stroke mechanism was cardioembolism (76.0%). Multivariate analysis demonstrated that smoking and history of previous ischemic stroke were independently associated with cases. High CHADS2 score (> or =3) or CHA2DS2-VASc score (> or =5), in particular, with previous ischemic stroke along with > or =1 point of other components of CHADS2 score or > or =3 points of other components of CHA2DS2-VASc score was a significant predictor for development of ischemic stroke. CONCLUSION: NVAF patients with high CHADS2/CHA2DS2-VASc scores and a previous ischemic stroke or smoking history are at high risk of stroke despite optimal warfarin treatment. Some other measures to reduce the risk of stroke would be necessary in those specific groups of patients.
Aged ; Aged, 80 and over ; Anticoagulants/adverse effects/*therapeutic use ; Atrial Fibrillation/*complications ; Cardiovascular Diseases ; Case-Control Studies ; Cerebral Infarction/complications ; Female ; Humans ; Male ; Middle Aged ; Multivariate Analysis ; Risk Factors ; Stroke/etiology/*prevention & control ; Warfarin/adverse effects/*therapeutic use

PURPOSE: In this study, we investigated the stroke mechanism and the factors associated with ischemic stroke in patients with nonvalvular atrial fibrillation (NVAF) who were on optimal oral anticoagulation with warfarin. MATERIALS AND METHODS: This was a multicenter case-control study. The cases were consecutive patients with NVAF who developed cerebral infarction or transient ischemic attack (TIA) while on warfarin therapy with an international normalized ratio (INR) > or =2 between January 2007 and December 2011. The controls were patients with NVAF without ischemic stroke who were on warfarin therapy for more than 1 year with a mean INR > or =2 during the same time period. We also determined etiologic mechanisms of stroke in cases. RESULTS: Among 3569 consecutive patients with cerebral infarction or TIA who had NVAF, 55 (1.5%) patients had INR > or =2 at admission. The most common stroke mechanism was cardioembolism (76.0%). Multivariate analysis demonstrated that smoking and history of previous ischemic stroke were independently associated with cases. High CHADS2 score (> or =3) or CHA2DS2-VASc score (> or =5), in particular, with previous ischemic stroke along with > or =1 point of other components of CHADS2 score or > or =3 points of other components of CHA2DS2-VASc score was a significant predictor for development of ischemic stroke. CONCLUSION: NVAF patients with high CHADS2/CHA2DS2-VASc scores and a previous ischemic stroke or smoking history are at high risk of stroke despite optimal warfarin treatment. Some other measures to reduce the risk of stroke would be necessary in those specific groups of patients.
Aged ; Aged, 80 and over ; Anticoagulants/adverse effects/*therapeutic use ; Atrial Fibrillation/*complications ; Cardiovascular Diseases ; Case-Control Studies ; Cerebral Infarction/complications ; Female ; Humans ; Male ; Middle Aged ; Multivariate Analysis ; Risk Factors ; Stroke/etiology/*prevention & control ; Warfarin/adverse effects/*therapeutic use

BACKGROUND/AIMS: The risk of gastrointestinal (GI) bleeding with dabigatran when compared to warfarin has been controversial in the literature. The aim of our study was to assess this risk with the use of dabigatran. METHODS: We examined the medical records of patients who were started on dabigatran or warfarin from October 2010 to October 2012. The study was conducted in two hospitals. RESULTS: A total of 417 patients were included (208 dabigatran vs. 209 warfarin). GI bleeding occurred in 10 patients (4.8%) in the dabigatran group compared to 21 patients (10.1%) in the warfarin group (p=0.0375). Multivariate analysis showed that patients who were on dabigatran for < or =100 days had a higher incidence of GI bleeding than those who were on it for >100 days (p=0.0007). The odds of GI bleeding in patients who were on dabigatran for < or =100 days was 8.2 times higher compared to those who were on the drug for >100 days. The incidence of GI bleeding in patients >65 years old was higher than in those <65 years old (p=0.0453, OR=3). History of previous GI bleeding was another risk factor for GI bleeding in the dabigatran group (p=0.036, OR=6.3). The lower GI tract was the most common site for GI bleeding in the dabigatran group (80.0% vs. 38.1%, p=0.014). CONCLUSIONS: The risk of GI bleeding was lower with dabigatran. The risk factors for GI bleeding with dabigtran were the first 100 days, age >65 years, and a history of previous GI bleeding.
Age Factors ; Aged ; Aged, 80 and over ; Anticoagulants/*adverse effects/therapeutic use ; Atrial Fibrillation/drug therapy ; Dabigatran/*adverse effects/therapeutic use ; Female ; Gastrointestinal Hemorrhage/*chemically induced/epidemiology/mortality ; Humans ; Incidence ; Kaplan-Meier Estimate ; Male ; Middle Aged ; Multivariate Analysis ; Odds Ratio ; Retrospective Studies ; Risk Factors ; Warfarin/*adverse effects/therapeutic use

Abdominal Wall ; blood supply ; Anticoagulants ; adverse effects ; Gastrointestinal Hemorrhage ; diagnosis ; etiology ; Hematoma ; diagnosis ; etiology ; Humans ; Male ; Middle Aged ; Warfarin ; adverse effects

The safety and efficacy of combined low dose aspirin and warfarin therapy in patients with atrial fibrillation after mechanical heart valve replacement were evaluated. A total of 1016 patients (620 females, mean age of 36.8±7.7 years) admitted for cardiac valve replacement and complicated with atrial fibrillation after surgery were randomly divided into study (warfarin plus 75-100 mg aspirin) or control (warfarin only) groups. International normalized ratio (INR) and prothrombin time were maintained at 1.8-2.5 and 1.5-2.0 times the normal values, respectively. Thromboembolic events and major bleedings were registered during the follow-up period. Patients were followed up for 24±9 months. The average dose of warfarin in the study and control groups was 2.91±0.83 mg and 2.88±0.76 mg, respectively (P>0.05). The incidence of overall thromboembolic events in study group was lower than that in control group (2.16% vs. 4.35%, P=0.049). No statistically significant differences were found in hemorrhage events (3.53% vs. 3.95%, P=0.722) or mortality (0.20% vs. 0.40%, P=0.559) between the two groups. Combined low dose aspirin and warfarin therapy in the patients with atrial fibrillation following mechanical heart valve replacement significantly decreased thromboembolic events as compared with warfarin therapy alone. This combined treatment was not associated with an increase in the risk of major bleeding or mortality.
Adult ; Anticoagulants ; administration & dosage ; Aspirin ; administration & dosage ; Atrial Fibrillation ; blood ; drug therapy ; etiology ; Female ; Fibrinolytic Agents ; administration & dosage ; Heart Valve Prosthesis ; Heart Valve Prosthesis Implantation ; adverse effects ; Humans ; International Normalized Ratio ; Male ; Postoperative Complications ; blood ; drug therapy ; Prothrombin Time ; Warfarin ; administration & dosage

Anticoagulants ; adverse effects ; pharmacology ; Blood Coagulation Disorders ; chemically induced ; Drug Interactions ; Humans ; Warfarin ; adverse effects ; pharmacology