We're unable to sign you in at this time. Please try again in a few minutes.
We were able to sign you in, but your subscription(s) could not be found. Please try again in a few minutes.
There may be a problem with your account. Please contact the AMA Service Center to resolve this issue.
Contact the AMA Service Center:
Telephone: 1 (800) 262-2350 or 1 (312) 670-7827  *   Email: subscriptions@jamanetwork.com
Error Message ......

Fecal Hemoglobin Excretion in Elderly Patients With Atrial Fibrillation Combined Aspirin and Low-Dose Warfarin vs Conventional Warfarin Therapy

Joseph L. Blackshear, MD; Vickie S. Baker, RN; Anne Holland, RN; Scott C. Litin, MD; David A. Ahlquist, MD; Robert G. Hart, MD; Ralph Ellefson, PhD; Jodi Koehler, MS
Arch Intern Med. 1996;156(6):658-660. doi:10.1001/archinte.1996.00440060086010.
Text Size: A A A
Published online


Background:  Antithrombotic prophylaxis using combined aspirin and low-dose warfarin is under evaluation in several clinical trials. However, combination therapy may result in increased gastrointestinal blood loss and clinical bleeding vs conventional single-agent antithrombotic therapy.

Methods:  To assess differences in gastrointestinal blood loss, we measured quantitative fecal hemoglobin equivalents (HemoQuant, Mayo Medical Laboratory, Rochester, Minn) in 117 patients, mean age 71 years, 1 month after initiation of assigned therapy in the Stroke Prevention in Atrial Fibrillation III Study. Sixty-three of these patients who had characteristics for high risk of stroke were randomly assigned to conventional adjusted-dose warfarin therapy (international normalized ratio, 2.0 to 3.0) or low-dose combined therapy (warfarin [international normalized ratio, <1.5] plus 325 mg/d of entericcoated aspirin). The remaining 54 patients with low risk of stroke received 325 mg/d of enteric-coated aspirin.

Results:  Among the 63 patients at high risk of stroke, abnormal values (>2 mg of hemoglobin per gram of stool) were detected in 11% and values greater than 4 mg of hemoglobin per gram of stool were found in 8%. Mean (±SD) values were more for those randomly assigned to receive combined therapy (1.7±3.3 mg of hemoglobin per gram of stool vs adjusted-dose warfarin therapy, 1.0± 1.9 mg/g; P=.003). The 54 nonrandomized patients with low risk of stroke receiving aspirin alone had a mean (±SD) Hemo-Quant value of 0.8±0.7 mg of hemoglobin per gram of stool 1 month after entry in the study.

Conclusions:  Abnormal levels of fecal hemoglobin excretion were common in elderly patients with high risk of atrial fibrillation 1 month after randomization to prophylactic antithrombotic therapy. Combined warfarin and aspirin therapy was associated with greater fecal hemoglobin excretion than standard warfarin therapy, suggesting the potential for increased gastrointestinal hemorrhage.(Arch Intern Med. 1996;156:658-660)


Sign in

Purchase Options

• Buy this article
• Subscribe to the journal
• Rent this article ?





Also Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
Please click the checkbox indicating that you have read the full article in order to submit your answers.
Your answers have been saved for later.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.


Some tools below are only available to our subscribers or users with an online account.

19 Citations

Sign in

Purchase Options

• Buy this article
• Subscribe to the journal
• Rent this article ?

Related Content

Customize your page view by dragging & repositioning the boxes below.