Evidence-Based Answers

Evidence Central™ is an integrated web and mobile solution that helps clinicians quickly answer etiology, diagnosis, treatment, and prognosis questions using the latest evidence-based research.


Evidence Central for Mobile Devices

Evidence Central iOS iPhone iPad Android

Evidence Central from Unbound Medicine, available for iOS® and Android™, is optimized for each platform and features superior navigation, so answers are easy to find at the bedside or anywhere they’re needed. Learn More

Word of the Day

Antioxidants, CoQ ineffective for patients with Alzheimer disease

Clinical Question:
Do antioxidants improve outcomes in patients with Alzheimer disease?

Bottom Line:
After 16 weeks of treatment, antioxidants and coenzyme Q are no more effective than placebo in slowing cognitive and functional declines in patients with Alzheimer disease. (LOE = 2b)

Galasko DR, Peskind E, Clark CM, et al, for the Alzheimer's Disease Cooperative Study. Antioxidants for Alzheimer disease: a randomized clinical trial with cerebrospinal fluid biomarker measures. Arch Neurol 2012 Mar 19. [Epub ahead of print]  [PMID:22431837]

Study Design:
Randomized controlled trial (double-blinded)



Outpatient (specialty)

These researchers randomly assigned 78 adults aged between 50 years and 85 years with Alzheimer disease to receive antioxidants (800 IU vitamin E plus 500 mg of vitamin C plus 900 mg of alpha-lipoic acid daily; n = 26) co-enzyme Q (400 mg 3 times daily; n = 26), or placebo (n = 26). Patients received pills 3 times daily to preserve masking. The researchers evaluated patients at baseline and at 8 weeks and 16 weeks after enrollment. In addition to clinical measures of dementia (eg, Mini-Mental State Examination, Alzheimer’s Disease Cooperative Study Activities of Daily Living, and so forth), the researchers performed lumbar punctures at baseline and at 16 weeks. The authors describe no significant changes in cerebrospinal fluid markers of Alzheimer disease and no change in clinically relevant measures of cognition. They found a larger decline in cognition and function in the antioxidant-treated patients, but it the declines do not appear to be statistically significant. Sixteen patients (20%) dropped out of the study. Generally speaking, when more than 20% of participants drop out, the potential for worrisome bias reaches a critical threshold and the bias tends to make intervention patients look better than control patients. Since the intervention looks ineffective, in this case, the bias actually strengthens the conclusions!


Site Licenses

Site license

Site Licenses are available for schools, universities, hospitals, government agencies, and companies. For more information, contact us.