Informant Questionnaire on Cognitive Decline in the Elderly

Last updated
Informant Questionnaire on Cognitive Decline in the Elderly
Synonyms IQCODE
Purposedetermine whether that person has declined in cognitive functioning

The Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) is a questionnaire that can be filled out by a relative or other supporter of an older person to determine whether that person has declined in cognitive functioning. The IQCODE is used as a screening test for dementia. If the person is found to have significant cognitive decline, then this needs to be followed up with a medical examination to determine whether dementia is present.

Contents

Rationale behind the IQCODE

Most screening tests for dementia involve a brief list of questions to directly assess cognitive functioning. Probably the best-known dementia screening test of this kind is the mini–mental state examination. A disadvantage of such tests is that they are affected by the person's level of education, familiarity with the dominant language and culture in their country, and level of intelligence before the onset of dementia. [1]

Because of this, cognitive screening tests can falsely indicate dementia in people with lower education, culturally and linguistically diverse backgrounds, and lower intelligence. Cognitive screening tests may also have the opposite problem, falsely indicating that a person does not have dementia, especially if that person had a higher level of education or intelligence originally. The IQCODE attempts to overcome this problem by assessing change from earlier in life, rather than the person's current level of functioning. It does this by making use of the informant's knowledge of both the person's earlier and current cognitive functioning.

Content

The IQCODE lists 26 everyday situations where a person has to use their memory or intelligence. [2] Examples of such situations include: “Remembering where to find things which have been put in a different place from usual” and “Handling money for shopping”. Each situation is rated by the informant for amount of change over the previous 10 years, using the following scale: 1. Much improved, 2. A bit improved, 3. Not much change, 4. A bit worse, 5. Much worse.

Scoring

The IQCODE is generally scored by averaging the ratings across the 26 situations. A person who has no cognitive decline will have an average score of 3, while scores of greater than 3 indicate that some decline has occurred. However, some users of the IQCODE have scored it by summing the scores to give a range from 26 to 130. [3]

Various cutoff scores have been used to distinguish dementia from normality. In community samples, cutoff scores for likely dementia have ranged from 3.3 and above to 3.6 and above, while in patient samples the cutoff scores have ranged from 3.4 and above to 4.0 and above. [3]

To improve the detection of dementia, the IQCODE can be used in combination with the Mini-Mental State Examination. A graphical method of combining the two tests has been developed and is known as the Demegraph. [4]

Validity of the IQCODE

The IQCODE has been found to distinguish people who have or do not have dementia. A low score on the IQCODE in a person who does not currently have dementia has also been found to predict that they will develop dementia in the future. [3]

The IQCODE has found to correlate highly with conventional dementia screening tests, such as the Mini-Mental State Examination, and to have moderate correlations with a range of neuropsychological tests. It has also been found to correlate with change in cognitive test scores over time. [3]

The IQCODE has near-zero correlations with a person's level of education or with their intelligence earlier in life. This is in contrast to conventional dementia screening tests like the Mini-Mental State Examination, which are affected by education and intelligence as well as the presence of dementia. [3]

A Cochrane review conducted in 2021 focused on the use of the IQCODE in primary care settings for the detection of dementia was unable to provide any guidance due to a surprising lack of research in this specific area. [5]

Other versions of the IQCODE

The original IQCODE has 26 items. A Short IQCODE has been developed, consisting of the 16 items, and has been found to be as valid as the full version. [6] Because it is briefer and of equal validity, the Short IQCODE can generally be used in preference to the original version. [7]

Because the IQCODE does not require the involvement of the person being assessed, it can be used to assess probable dementia in someone who is unable to be assessed because they have had a stroke, developed delirium or have died. A Retrospective IQCODE has been developed for this purpose. [3]

The IQCODE has been translated into many languages, including Chinese, Danish, Dutch, Finnish, French, Canadian French, German, Italian, Japanese, Korean, Norwegian, Polish, Portuguese, Spanish and Thai.

See also

Related Research Articles

<span class="mw-page-title-main">Dementia</span> Long-term brain disorders causing impaired memory, thinking and behavior

Dementia is the general name for a decline in cognitive abilities that impacts a person's ability to perform everyday activities. This typically involves problems with memory, thinking, and behavior. Aside from memory impairment and a disruption in thought patterns, the most common symptoms include emotional problems, difficulties with language, and decreased motivation. The symptoms may be described as occurring in a continuum over several stages. Dementia ultimately has a significant effect on the individual, caregivers, and on social relationships in general. A diagnosis of dementia requires the observation of a change from a person's usual mental functioning and a greater cognitive decline than what is caused by normal aging.

Delirium is a specific state of acute confusion attributable to the direct physiological consequence of a medical condition, effects of a psychoactive substance, or multiple causes, which usually develops over the course of hours to days. As a syndrome, delirium presents with disturbances in attention, awareness, and higher-order cognition. People with delirium may experience other neuropsychiatric disturbances, including changes in psychomotor activity, disrupted sleep-wake cycle, emotional disturbances, disturbances of consciousness, or, altered state of consciousness, as well as perceptual disturbances, although these features are not required for diagnosis.

Psychological testing refers to the administration of psychological tests. Psychological tests are administered or scored by trained evaluators. A person's responses are evaluated according to carefully prescribed guidelines. Scores are thought to reflect individual or group differences in the construct the test purports to measure. The science behind psychological testing is psychometrics.

Vascular dementia (VaD) is dementia caused by problems in the blood supply to the brain, resulting from a cerebrovascular disease. Restricted blood supply (ischemia) leads to cell and tissue death in the affected region, known as an infarct. The three types of vascular dementia are subcortical vascular dementia, multi-infarct dementia, and stroke related dementia. Subcortical vascular dementia is brought about by damage to the small blood vessels in the brain. Multi-infarct dementia is brought about by a series of mini-strokes where many regions have been affected. The third type is stroke related where more serious damage may result. Such damage leads to varying levels of cognitive decline. When caused by mini-strokes, the decline in cognition is gradual. When due to a stroke, the cognitive decline can be traced back to the event.

<span class="mw-page-title-main">Neuropsychological test</span> Assess neurological function associated with certain behaviors and brain damage

Neuropsychological tests are specifically designed tasks that are used to measure a psychological function known to be linked to a particular brain structure or pathway. Tests are used for research into brain function and in a clinical setting for the diagnosis of deficits. They usually involve the systematic administration of clearly defined procedures in a formal environment. Neuropsychological tests are typically administered to a single person working with an examiner in a quiet office environment, free from distractions. As such, it can be argued that neuropsychological tests at times offer an estimate of a person's peak level of cognitive performance. Neuropsychological tests are a core component of the process of conducting neuropsychological assessment, along with personal, interpersonal and contextual factors.

Cognitive disorders (CDs), also known as neurocognitive disorders (NCDs), are a category of mental health disorders that primarily affect cognitive abilities including learning, memory, perception, and problem-solving. Neurocognitive disorders include delirium, mild neurocognitive disorders, and major neurocognitive disorder. They are defined by deficits in cognitive ability that are acquired, typically represent decline, and may have an underlying brain pathology. The DSM-5 defines six key domains of cognitive function: executive function, learning and memory, perceptual-motor function, language, complex attention, and social cognition.

The mini–mental state examination (MMSE) or Folstein test is a 30-point questionnaire that is used extensively in clinical and research settings to measure cognitive impairment. It is commonly used in medicine and allied health to screen for dementia. It is also used to estimate the severity and progression of cognitive impairment and to follow the course of cognitive changes in an individual over time; thus making it an effective way to document an individual's response to treatment. The MMSE's purpose has been not, on its own, to provide a diagnosis for any particular nosological entity.

The Abbreviated Mental Test score (AMTS) is a 10-point test for rapidly assessing elderly patients for the possibility of dementia. It was first used in 1972, and is now sometimes also used to assess for mental confusion and other cognitive impairments.

Postoperative cognitive dysfunction (POCD) is a decline in cognitive function that may last from 1–12 months after surgery, or longer. In some cases, this disorder may persist for several years after major surgery. POCD is distinct from emergence delirium. Its causes are under investigation and occurs commonly in older patients and those with pre-existing cognitive impairment.

Cognitive impairment is an inclusive term to describe any characteristic that acts as a barrier to the cognition process or different areas of cognition. Cognition, also known as cognitive function, refers to the mental processes of how a person gains knowledge, uses existing knowledge, and understands things that are happening around them using their thoughts and senses. A cognitive impairment can be in different domains or aspects of a person's cognitive function including memory, attention span, planning, reasoning, decision-making, language, executive functioning, and visuospatial functioning. The term cognitive impairment covers many different diseases and conditions and may also be symptom or manifestation of a different underlying condition. Examples include impairments in overall intelligence ,specific and restricted impairments in cognitive abilities, neuropsychological impairments, or it may describe drug-induced impairment in cognition and memory. Cognitive impairments may be short-term, progressive or permanent.

Psychological therapies for dementia are starting to gain some momentum. Improved clinical assessment in early stages of Alzheimer's disease and other forms of dementia, increased cognitive stimulation of the elderly, and the prescription of drugs to slow cognitive decline have resulted in increased detection in the early stages. Although the opinions of the medical community are still apprehensive to support cognitive therapies in dementia patients, recent international studies have started to create optimism.

<span class="mw-page-title-main">Trail Making Test</span> Neuropsychological test

The Trail Making Test is a neuropsychological test of visual attention and task switching. It has two parts, in which the subject is instructed to connect a set of 25 dots as quickly as possible while maintaining accuracy. The test can provide information about visual search speed, scanning, speed of processing, mental flexibility, and executive functioning. It is sensitive to cognitive impairment associated with dementia, including Alzheimer's disease.

A depression rating scale is a psychometric instrument (tool), usually a questionnaire whose wording has been validated with experimental evidence, having descriptive words and phrases that indicate the severity of depression for a time period. When used, an observer may make judgements and rate a person at a specified scale level with respect to identified characteristics. Rather than being used to diagnose depression, a depression rating scale may be used to assign a score to a person's behaviour where that score may be used to determine whether that person should be evaluated more thoroughly for a depressive disorder diagnosis. Several rating scales are used for this purpose.

The General Practitioner Assessment of Cognition (GPCOG) is a brief screening test for cognitive impairment introduced by Brodaty et al. in 2002. It was specifically developed for the use in the primary care setting.

<span class="mw-page-title-main">Montreal Cognitive Assessment</span> Screening assessment for detecting cognitive impairment

The Montreal Cognitive Assessment (MoCA) is a widely used screening assessment for detecting cognitive impairment. It was created in 1996 by Ziad Nasreddine in Montreal, Quebec. It was validated in the setting of mild cognitive impairment (MCI), and has subsequently been adopted in numerous other clinical settings. This test consists of 30 points and takes 10 minutes for the individual to complete. The original English version is performed in seven steps, which may change in some countries dependent on education and culture. The basics of this test include short-term memory, executive function, attention, focus, and more.

The Addenbrooke's Cognitive Examination (ACE) and its subsequent versions are neuropsychological tests used to identify cognitive impairment in conditions such as dementia.

The Mood Disorder Questionnaire (MDQ) is a self-report questionnaire designed to help detect bipolar disorder. It focuses on symptoms of hypomania and mania, which are the mood states that separate bipolar disorders from other types of depression and mood disorder. It has 5 main questions, and the first question has 13 parts, for a total of 17 questions. The MDQ was originally tested with adults, but it also has been studied in adolescents ages 11 years and above. It takes approximately 5–10 minutes to complete. In 2006, a parent-report version was created to allow for assessment of bipolar symptoms in children or adolescents from a caregiver perspective, with the research looking at youths as young as 5 years old. The MDQ has become one of the most widely studied and used questionnaires for bipolar disorder, and it has been translated into more than a dozen languages.

The Saint Louis University Mental Status (SLUMS) Exam is a brief screening assessment used to detect cognitive impairment. It was developed in 2006 at the Saint Louis University School of Medicine Division of Geriatric Medicine, in affiliation with a Veterans' Affairs medical center. The test was initially developed using a veteran population, but has since been adopted as a screening tool for any individual displaying signs of mild cognitive impairment. The intended population typically consists of individuals 60 years and above that display any signs of cognitive deficit. Unlike other widely-used cognitive screens, such as the Mini-Mental State Examination and Montreal Cognitive Assessment, the SLUMS is free to access and use by all healthcare professionals.

The Self-administered Gerocognitive Examination is a brief cognitive assessment instrument for mild cognitive impairment (MCI) and early dementia, created by Douglas Scharre, Professor of Clinical Neurology and Psychiatry at Ohio State University Wexner Medical Center in Columbus, Ohio.

References

  1. Jorm, A.F. (1996). "Assessment of cognitive impairment and dementia using informant reports". Clinical Psychology Review. 16: 51–73. doi:10.1016/0272-7358(95)00056-9.
  2. Jorm, A. F.; Jacomb, P. A. (1989). "The Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE): Socio-demographic correlates, reliability, validity and some norms". Psychological Medicine. 19 (4): 1015–1022. doi:10.1017/S0033291700005742. PMID   2594878. S2CID   42984982.
  3. 1 2 3 4 5 6 Jorm, Anthony F. (2004). "The Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE): A review". International Psychogeriatrics. 16 (3): 275–293. doi:10.1017/S1041610204000390. PMID   15559753. S2CID   145256616.
  4. MacKinnon, Andrew; Mulligan, Reinhild (1998). "Combining Cognitive Testing and Informant Report to Increase Accuracy in Screening for Dementia". American Journal of Psychiatry. 155 (11): 1529–1535. doi:10.1176/ajp.155.11.1529. PMID   9812113.
  5. Burton, Jennifer K; Fearon, Patricia; Noel-Storr, Anna H; McShane, Rupert; Stott, David J; Quinn, Terry J (2021-07-19). Cochrane Dementia and Cognitive Improvement Group (ed.). "Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) for the detection of dementia within a general practice (primary care) setting". Cochrane Database of Systematic Reviews. 2021 (7): CD010771. doi:10.1002/14651858.CD010771.pub3. PMC   8406468 . PMID   34278564.
  6. Jorm, A. F. (1994). "A short form of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE): Development and cross-validation". Psychological Medicine. 24 (1): 145–153. doi:10.1017/S003329170002691X. PMID   8208879. S2CID   43263986.
  7. Quinn, Terry J; Fearon, Patricia; Noel-Storr, Anna H; Young, Camilla; McShane, Rupert; Stott, David J (2021-07-19). Cochrane Dementia and Cognitive Improvement Group (ed.). "Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) for the detection of dementia within community dwelling populations". Cochrane Database of Systematic Reviews. 2021 (7): CD010079. doi:10.1002/14651858.CD010079.pub3. PMC   8407460 . PMID   34278562.