Mental status testing can be an important tool for detecting cognitive decline. Unfortunately, mental status testing is not done on a regular basis in primary care. The vast majority of people with cognitive impairment are detected only after they or their family members report cognitive or memory concerns to healthcare providers. When most cognitive impairment is detected, patients are further along the trajectory of cognitive decline and likely outside the optimal window for pharmacological or nonpharmacological (lifestyle and psychosocial) interventions (Jannati et al., 2024).
5.1 Neurocognitive Screening
Neurocognitive screening is used to detect cognitive changes before an individual would normally seek medical care. Screening ideally identifies very early signs of dementia and allows a clinician to make a referral for a more thorough cognitive evaluation.
The Affordable Care Act directs clinicians to assess their Medicare patients for possible cognitive impairment during their Annual Wellness Visit. This is intended to address the fact that as many, if not most of patients with dementia are unrecognized in the primary care setting (USPSTF, 2020, February 25).
5.2 Screening Tools
Screening tests are not intended to diagnose cognitive impairment or dementia; a positive screening test result should lead to additional testing. The most widely studied tool for neurocognitive screening is the Mini Mental State Examination. The Mini Mental State Exam (MMSE) is a 30-point instrument with 11 items that has been studied in various populations. Although sensitivity* and specificity** vary depending on the patient's age and education level, a general cut point of 23/24 or 24/25 is appropriate for most primary care populations (USPSTF, 2020, February 25).
*Sensitivity: The sensitivity of a clinical test refers to the ability of the test to correctly identify those patients with the disease.
**Specificity: The specificity of a clinical test refers to the ability of the test to correctly identify those patients without the disease.
Another widely used screening tool is the Montreal Cognitive Assessment. It is a 30-point test that assesses short term memory recall, visuospatial abilities, and several aspects of executive function. It takes about 10 minutes to complete with a score of 26 or above considered normal.
The Saint Louis University Mental Status exam is an assessment tool for mild cognitive impairment and dementia. It assesses 11 cognitive domains. A recent systematic review of this tool indicated that it appears to have adequate validity, sensitivity, and specificity in detecting cognitive impairment. Shortcomings included a lack of sufficient normative data, information on test-reliability, and limited application of other measures such as imaging studies and biomarkers (Spencer et al., 2022).
The Mini-Cog is a neuropsychological test that has been shown to be effective in detecting patients with dementia. Although its accuracy varies by region and method of interpretation, it has been shown to yield high sensitivity and specificity for detecting cognitive impairment. The test, consisting of a clock drawing test and three-item recall test, takes only 3 minutes to administer, making it suitable for use in a primary care setting (Limpawattana and Manjavong, 2021).
Administration of the clock drawing test alone allows for the differentiation of mild cognitive impairment and normal cognition with good sensitivity and excellent specificity. Additionally, patients with mild cognitive impairment often have episodic memory deficit, which means that a recall test on its own may also be useful in screening for mild cognitive impairment (Limpawattana and Manjavong, 2021).
The General Practitioner Assessment of Cognition (GPCOG) is a screening tool used to assess cognitive impairment and dementia in primary care. It is simple, brief, efficient, reliable, and valid and can meet the needs of general practitioners (Patil et al., 2020).
It has two sections a patient examination (GPCOG-patient, part 1) with a maximum score of 9, and a caregiver interview (part 2) with a maximum score of 6. Part 1 score of 9 indicates no cognitive impairment, someone scoring 4 points or less is very likely to have cognitive impairment (Patil et al., 2020).
The advantages of the GPCOG over current brief screening instruments are that it combines patient and informant data, is quick to administer, has been validated in a primary care setting, and has sound psychometric properties. Psychometrically, it performed better as a screening instrument than the AMT and slightly (although non significantly) better than the MMSE but was quicker and likely to be more acceptable to GPs and patients (Patil et al., 2020).
Although the GPCOG has been translated into several languages, there isn't enough research on how different cultures and languages might affect the test's results. This test requires the physical ability to write or draw. If the person cannot hold a pen or pencil, they will be unable to complete the clock drawing portion of the test (Heerema, 2022).
Other screening instruments include the Memory Impairment Screen, Abbreviated Mental Test, Short Portable Mental Status Questionnaire, Free and Cued Selective Reminding Test, 7-Minute Screen, Telephone Interview for Cognitive Status, and Informant Questionnaire on Cognitive Decline in the Elderly (USPSTF, 2020, February 25).
5.3 Limitations of Neurocognitive Screens
Most cognitive screening tools emphasize the detection of memory dysfunction but neglect other domains such as visuospatial or executive functions. However, an estimated 40-50% of dementias are caused by non-AD diseases, most commonly Lewy body disease, frontal-temporal dementia, and vascular disease, which frequently present with non-memory symptoms. Even AD can present with dysfunction in visuospatial, executive, or language rather than memory (Possin et al., 2018).
Despite a large body of evidence examining cognitive screening instruments, most instruments have been tested in only a few well-designed studies (USPSTF, 2020, February 25). Cognitive screens typically rely on a single, global cut-off score, which may fail to detect non-memory deficiencies. Few screening tools provide a valid profile of spared and impaired cognitive domains that could be used to assist with differential diagnosis. Brief screens rarely evaluate functional decline and neurobehavioral changes (Possin et al., 2018).
Mini Mental State Examination and the Montreal Cognitive Assessment tests have limitations, namely, they are not very sensitive to mild impairment, particularly in conditions other than Alzheimer’s disease. The MMSE also shows education, language, and cultural biases (Yang et al., 2016) and both tools may be impractical as screening tools because they take at least 10 minutes to complete.
A Cochrane review of the effectiveness of the Mini-Cog found that it had a sensitivity of 76%, indicating that it failed to detect up to 24% of individuals who have dementia (e.g. false negatives). The specificity of the Mini-Cog was 73% indicating that up to 27% of individuals may be incorrectly identified as having dementia when these individuals do not actually have an underlying dementia (e.g. false positives). The review concluded that at the present time there is not enough evidence to support the routine use of the Mini-Cog as a screening test for dementia in primary care and additional studies are required before concluding that the Mini-Cog is useful in this setting (Seitz et al., 2021).
Language barriers and cultural differences are major barriers to successful screening. Limitations include:
- How the questions are asked.
- The validity of questions.
- How much time the client is given to answer.
- Comfort with the person giving the test.
- Your knowledge of a person’s baseline.
Developing an effective dementia screening tool is challenging because the assessment of cognitive deficits is time-consuming and requires specialized knowledge and strong familiarity with neurologic diseases; inaccurate diagnoses are common. Because of these obstacles, the U.S. Preventive Services Task Force (USPSTF) has recommended that, for cognitive impairment in older adults, current evidence is insufficient to assess the balance of benefits and harms of screening for cognitive impairment (USPSTF, 2020, February 25).
5.4 Alerting Healthcare Personnel to Changes in a Client’s Cognition
If you are working with a client and notice or suspect a change in mental status, try to determine whether your client is operating at his or her normal level or whether something has changed. If you notice something different in the person’s behavior or demeanor—especially if the change is sudden—report your concerns to the nursing staff immediately. They will assess the client and decide on the next course of action.