Dementia is a disease projected to affect approximately 82 million people worldwide by 2030, with a 20% risk of disease in those reaching age 45.1-3 Even with this knowledge, research demonstrates that cognitive decline goes unrecognized in 21% to 81% of affected patients in primary care settings. Screening for cognitive impairment is imperative, and public policy efforts are beginning to reflect this. Primary care providers have a responsibility to be knowledgeable about dementia and the validated screening tools available for early detection, thereby ensuring early diagnosis and optimal outcomes.4,5
For the purposes of this article, the terms cognitive decline and cognitive impairment are synonymous and are not diagnostic terms. As described by Borson et al, “Cognition is a complex group of mental processes that includes memory, attention, language, and decision making, and mild impairment of cognition may be an early sign of a disease that will lead to dementia.”6 Dementia is a diagnosis, and screening is only a method to evaluate common symptoms of the disease, notably cognitive impairment. However, providers need to critically appraise many differential diagnostic considerations when an individual screens positive for cognitive impairment.
Benefits of Screening
Recent advances in dementia research are making it advantageous to screen for and identify dementia. A simulation analysis by Liu and colleagues assessed the readiness of the US healthcare system when emerging dementia treatments become available outside of clinical trials.7 Although there are no disease-modifiable treatments currently available, there is guarded optimism that one may become available as early as 2020. These upcoming therapies include anti-beta amyloid and anti-tau antibodies that work by removing plaques present in Alzheimer disease specifically. The report stresses that with treatment modalities on the horizon, the need for routine screening is pressing.7
Past analyses for the development of universal screening guidelines for cognitive decline by the US Preventive Services Task Force (USPSTF) have resulted in insufficient evidence to empirically support routine screening.8 Although evidence is lacking, the USPSTF does acknowledge that there may be clinical significance in screening. They report that screening could lead providers to evaluate and treat reversible causes of cognitive decline, discuss diagnostic and treatment options with patients, and anticipate future care needs in the disease process.8
In addition to preparing for the near future when disease-modifying treatments become available, early detection of cognitive decline offers other benefits. There is evidence in the literature, as recognized by the USPSTF, that some drug therapies including acetylcholinesterase inhibitors and memantine have a small effect on cognitive function.8 These therapies are approved for use by the US Food and Drug Administration. Outside of pharmacologic therapy, there is also evidence supporting short-term lifestyle strategies for sustaining cognition by increasing neuroplasticity.
Additionally, Howard and coworkers analyzed data from senior housing environment assessments to examine how everyday lifestyle options can support cognition.9 The investigators made a number of evidence-based recommendations that can be suggested to patients with the desire to preserve cognition. These interventions include engaging in physical activity and formal exercise, as well as the use of computers, crossword puzzles, handicrafts, and formal education courses.9
Borson and colleagues also wrote about the value of screening and the early detection of cognitive impairment.6 The notable recommendation included placing screening in the context of personalized care. For example, clinicians should follow Medicare’s Annual Wellness Visit guidelines and recognize the cognitive assessment requirement as a calling to provide comprehensive geriatric care with attention to cognition. By doing this, providers are considering the long-term care needs of aging patients.
When to Screen
A standard of practice for clinicians within the process of care is to perform or order preventive and diagnostic procedures based on a patient’s age and history.10 Age is the greatest risk factor for dementia, followed by family history.1 For clinicians who are caring for adults older than 65, the Affordable Care Act provides for a Medicare Annual Wellness Visit that requires an assessment for cognitive decline. This implies a new standard for all preventive health visits with older adults. Identifying cognitive impairment and the early detection of dementia is a responsibility for clinicians whether meeting with older adults in a wellness or preventive care encounter.
Lang et al explored worldwide prevalence and determinants of undetected dementia through a meta-analysis.11 The investigators calculated the prevalence of undetected dementia to be 61.7%. Associated risk factors for undetected dementia reported include lower socioeconomic status, patients younger than age 71 years, male gender, and patients living in the community vs residing in a residential facility. Interestingly, there was noted to be an increased rate of undetected dementia by general practitioners compared with other screeners, including those providing care in community settings. The researchers discuss the role that general practitioners must play in detection given the aging population and inability of aging and memory specialists to manage the increase in this population. These findings led the authors to recommend increased research focused on screening in low income areas to ensure diagnostic equality, as well as to educate primary care providers in dementia and screening methods. A stated weakness of this meta-analysis is the variation in methods used for diagnosing dementia, making it less efficient to compare rates of prevalence of dementia. This weakness supports the need for continued clarification for primary care providers to standardize screening and diagnosis of dementia diseases.11
To summarize, primary screening for cognitive impairment is an integrated component of any formal or informal neurologic examination. This is in addition to the recommendation for an annual cognitive screening assessment during wellness visits. Clinicians should think about overcoming complacency of “normal aging” cognitive impairment and be prepared to further explore deficits they assess or are voiced by a patient’s family, friends, and caregivers. Secondary screening practices, such as administering brief cognitive assessments, should be considered when triggered by variances from normal. Clinicians should also be developing strategies to specifically ensure screening of cohorts that have been identified as high risk for undetected dementia (ie, lower socioeconomic status, patients younger than 71 years, men, and patients living in the community vs a residential facility). These known risk factors are special considerations, although all adults older than age 65 warrant asymptomatic screening in the primary care setting.
Overcoming Barriers to Screening
Patients do not want to be told they are at risk for a condition that has limited interventions and treatment options.12 This is similar to when in the past, screening for cancer was feared due to lack of treatment options. Patient anxiety toward cognitive decline is associated with a fear of aging.9 This anxiety can prove to be a barrier to screening in primary care settings. However, it should not prevent clinicians from addressing dementia screening with patients and families.
Kirk Wiese and colleagues published a systematic review to analyze barriers to cognitive screening in rural US populations.13 The major barrier to cognitive screening, specifically in rural populations, was in the cognitive and emotional domain. This was defined as lacking knowledge and overt misconceptions by providers, patients, caregivers, and families. The authors also explain that lack of available information, denial of recognition of symptoms, futility of treatment, and fear of diagnosis were identified as emotional barriers to pursuing cognitive screening. Structural barriers to screen were consistent with rural health literature and include lack of transportation and health care access, as well as difficulty navigating health care services. Financial barriers included lack of health insurance and the postdiagnosis costs associated with treatment and additional provider visits. 13
A large portion of the recommendations in the systematic review involve using tools provided by the Alzheimer’s Association to educate providers on the benefits of and now the legal mandate to perform cognitive screening for patients older than age 65.13 The authors also strongly urge a public health response to inform Americans about cognitive screening and early detection of dementias. Some of the creative ways presented to reach older Americans residing in rural areas include the use of telemedicine, mobile health units, and tapping the networks already established in rural communities.13
Grober and colleagues reported that although screening programs have improved the recognition of dementia, they can raise anxiety for some patients.14 Additionally, they found that patients often did not follow-up for further diagnostic testing. As Kirk Wiese et al report, providers need to inform patients of the benefits of early diagnosis and explain how new treatment modalities may delay the progression of the ultimate disease process. 13 By increasing personal knowledge of dementia and Alzheimer disease including interventions, providers can have informed conversations with patients and families to reduce anxiety.