Diagnosing and Managing Patients With Dementia

Robbie Cooksey, DO

Private practice, Abilene, Texas

Janice Knebl, DO, MBA

The University of North Texas Health Science Center, Fort Worth

Prevalence and Impact of Dementia

AV 1. The Increasing Prevalence of Dementia by Age Group (00:25)

Data from Plassman et al3

Approximately 7.0 million US adults have some form of dementia,1 and about 5.4 million have the Alzheimer’s type of dementia.2 As the number of older Americans grows, the prevalence of dementia increases proportionally (AV 1).3 In 2011, the total annual health care costs for those with Alzheimer’s disease and other dementias is estimated to be $183 billion.2

Missed or Delayed Dementia Diagnosis

Dementia remains largely underrecognized and underdiagnosed in primary care. For example, one study4 found that 43% of primary care patients aged ≥ 75 years had cognitive impairment. Of those patients, less than one-fourth with mild cognitive impairment and less than one-half with moderate-to-severe cognitive impairment had been evaluated for dementia.

Another study5 reported that 56% of patients with cognitive impairment aged ≥ 55 years were not diagnosed by their PCPs. Although they had less severe cognitive impairment than those who were diagnosed, undiagnosed patients still had problems with daily activities such as taking medications, cooking, and managing finances.

Additionally, of the 5% of primary care patients aged ≥ 60 years found to have moderate-to-severe cognitive impairment, less than 25% were diagnosed with dementia.6 These patients were more likely to be hospitalized, visit the ER, or die in the following year compared with patients without cognitive impairment.

Many factors contribute to missed or delayed diagnoses of dementia.7 These factors include misconceptions, fears, and errors on the part of patients, caregivers, and health care providers, as well as problems inherent in the health care system. Clinicians can improve the rate of diagnosis of dementia by watching for the following problems and working to correct them when possible.

Patient and caregiver factors. Patients and their caregivers may not recognize symptoms of dementia because they lack education about the illness, may attribute the symptoms to other causes, or may assume that their cognitive changes are a normal part of aging.7 Thus, patients are unlikely to spontaneously report dementia symptoms and will likely need to be asked about them by their physicians. Some patients may refuse to be assessed for dementia because they want to avoid receiving this diagnosis or think that little can be done to help them. Patients and caregivers also may limit their encounters with physicians due to cost or lack of transportation.

Provider factors. Many clinicians need to know more about the presentation and diagnosis of dementia, as well as its treatment.7 Like some patients, physicians may believe that cognitive changes are a normal part of aging. Others may believe that the diagnosis is too difficult to make due to a perceived lack of useful assessment tools or think that a specialist should diagnose and treat dementia. Primary care physicians may prioritize patients’ physical health problems over cognitive problems or may delay making a diagnosis because they fear misdiagnosing patients. Clinicians may even believe that an early diagnosis is unnecessary because treatment options are limited. Additionally, physicians’ communication skills may not reliably solicit clues about cognitive changes from patients and their caregivers, especially when language or cultural barriers are involved.

Health care system factors. The health care system may not allow physicians enough time with each patient to accurately assess and diagnose dementia, may limit the availability of specialists for consultation during the diagnostic process, and may not provide adequate community resources for patients with dementia.7 Health care payers may also restrict access to dementia care and financial reimbursement for the diagnosis and management of this condition.


Benefits of Early Diagnosis

Although a host of factors can contribute to missed or delayed diagnosis, clinicians should strive to make an early diagnosis of dementia.2 When patients are screened in a timely manner, reversible causes of cognitive impairment and associated medical conditions can be treated. Additionally, medications that may worsen cognition can be avoided. Symptoms of dementia and behavioral problems can potentially be managed, and the patient may have the opportunity to enroll in a clinical trial of a treatment that would delay progression of the disorder. Further, patients and their families can be helped to adjust to the diagnosis, learn about the disease and available support services, and plan for the future.

A Toolkit for Diagnosing Dementia

AV 2. Model for Diagnosing Dementia (00:25)

Abbreviations are defined before the References

The diagnostic process begins with screening for dementia pathology, and, after confirmation of pathology, continues with a cognitive evaluation and differential diagnosis (AV 2). The tools listed below can help you in assessing and diagnosing your patients with cognitive impairment or dementia.

Screening. Aging patients should be routinely assessed for dementia, especially those who report memory problems or cognitive changes and those who are 80 years old or older. Brief but reliable screening tests include:

Cognitive evaluation. When administering cognitive evaluations, ask patients what changes in memory and/or behavior have occurred, such as aphasia, apraxia, and agnosia, and confirm the onset, duration, and progression of these changes. Also, ask patients if they have any relevant comorbidities, such as seizures, diabetes, stroke, and hypertension.

Pertinent components of the physical examination include the ADL/IADL for functioning assessment, the GDS short form for depression screening, and a focused neurologic evaluation for frontal release signs (including glabellar reflex). Laboratory and diagnostic tests to conduct include CBC, CMP, B12/folate, RPR, TSH, and brain imaging (ie, MRI, CT, and PET scans). Further cognitive testing can be conducted with the MoCA, MMSE, SLUMS, and AD8.

Differential diagnosis. After confirming cognitive deficits via a cognitive evaluation, the next step in diagnosing dementia is completing a differential diagnosis. Dementia may result from several disorders, such as Alzheimer’s disease, vascular dementia, Parkinson’s disease, Lewy body dementia, frontotemporal dementia, and normal pressure hydrocephalus (Table 1). Resources about these conditions are available for clinicians as well as patients and their families (Table 2).

Other conditions can also result in cognitive changes, including neurosyphilis, depression, alcohol use disorder, and demyelinating diseases. Therefore, clinicians must consider multiple disorders before making a definitive diagnosis.


As more Americans are living to older ages, the prevalence of dementia is increasing. Older patients who present to primary care offices often have some form of dementia, but various factors can cause the diagnosis to be missed. To recognize dementia and make a timely diagnosis, clinicians can routinely ask patients and their caregivers about changes in cognitive functioning and, when cognitive decline is suspected, complete the diagnostic process for dementia. This includes conducting a cognitive evaluation and performing a differential diagnosis. Several brief but reliable tools are available to aid in screening and evaluating patients for dementia.

For Clinical Use

  • Use brief tools to screen for dementia in patients aged 80 years or older and in younger patients who have cognitive changes or memory problems
  • If screening indicates dementia, conduct a cognitive evaluation and perform a differential diagnosis


AD = Alzheimer’s disease, AD8 = Eight-item Informant Interview to Differentiate Aging and Dementia, ADL/IADL = Activities of Daily Living/Instrumental ADL scales, CBC = complete blood count, CMP = comprehensive metabolic panel, CT = computed tomography, GDS = Geriatric Depression Scale, MCI = mild cognitive impairment, MMSE = Mini-Mental State Examination, MoCA = Montreal Cognitive Assessment, MRI = magnetic resonance imaging, PCP = primary care physician, PET = positron emission tomography, RPR = rapid plasma reagin, SLUMS = Saint Louis University Mental Status examination, TSH = thyroid stimulating hormone


  1. Neurologychannel.com. Dementia overview, types, incidence and prevalence. Published January 2, 2000. http://www.healthcommunities.com/dementia/dementia-overview-types.shtml. Accessed September 29, 2011.
  2. Alzheimer's Association, Thies W, Bleiler L. 2011 Alzheimer's disease facts and figures. Alzheimers Dement. 2011;7(2):208–244. http://www.alz.org/downloads/Facts_Figures_2011.pdf. Accessed September 29, 2011.
  3. Plassman BL, Langa KM, Fisher GG, et al. Prevalence of dementia in the United States: the aging, demographics, and memory study. Neuroepidemiology. 2007;29(1–2):125–132. PubMed
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  6. Callahan CM, Hendrie HC, Tierney WM. Documentation and evaluation of cognitive impairment in elderly primary care patients. Ann Intern Med. 1995;122(6):422–429. PubMed
  7. Bradford A, Kunik ME, Schulz P, et al. Missed and delayed diagnosis of dementia in primary care: prevalence and contributing factors. Alzheimer Dis Assoc Disord. 2009;23(4):306–314. PubMed