For adults aged 65 years or older living in the community, there is no benefit to screening for cognitive impairment if they are asymptomatic, according to a new Canadian guideline published in CMAJ (Canadian Medical Association Journal).
"While the task force recommends against screening older community-living adults for cognitive impairment, physicians should investigate if patients or their family members express concern about possible memory loss," states Dr. Kevin Pottie, chair of the Canadian Task Force on Preventive Health Care working group for the cognitive impairment guideline. "This recommendation is for adults without symptoms, not for people with concerns."
The recommendation updates the task force's previous recommendation that found insufficient evidence to recommend for or against screening, which was published in 2001. The current recommendation is based on a lack of evidence that screening is effective, a high rate of false-positive results for screening and the ineffectiveness of treatment for mild cognitive impairment. The task force found no clinical trials that evaluated the benefits or harms of screening for cognitive impairment, and instead looked at the effectiveness of treatment for mild cognitive impairment as indirect evidence to inform its recommendations on screening.
Cognitive impairment begins with normal age-related memory loss and may progress to mild cognitive impairment and possibly dementia. Although mild cognitive impairment is noticeable, it does not substantially affect daily living, unlike dementia. However, mild cognitive impairment can be a risk factor for later dementia, but it may not progress to that stage.
"Our assumptions were that, if clinicians are able to identify individuals with mild cognitive impairment early through screening and either slow down or stop its progression through effective treatment, the incidence of cognitive impairment (measured through cognition, function, behaviour and global status) may decline," the authors state.
- Cholinesterase inhibitors, a common treatment for Alzheimer disease, do not improve cognition in people with mild cognitive impairment.
- Dietary supplements and vitamins did not improve cognitive function in people with mild cognitive impairment.
- Nonpharmacologic interventions such as exercise and cognitive training may have some minor benefit, although the effect was not clinically significant.
The recommendation not to screen aligns with other national and international guidelines such as the United Kingdom's National Institute for Health and Care Excellence (NICE) 2011 guidelines and the US Preventive Services Task Force 2014 guidelines.
"The task force's findings have identified multiple opportunities for research," states Dr. Pottie. "It is clear that we need more precise screening tools and treatments, including preventive approaches that improve outcomes for people with cognitive impairment."
The guideline, as well as materials for physicians, is available at http://www.
The Canadian Task Force on Preventive Health Care has been established to develop clinical practice guidelines that support primary care providers in delivering preventive health care. The mandate of the task force is to develop and disseminate clinical practice guidelines for primary and preventive care, based on systematic analysis of scientific evidence.