Survey of Questions for Family Members of Alzheimers Patients

J Alzheimers Dis. Author manuscript; available in PMC 2011 Nov 3.

Published in final edited form as:

PMCID: PMC3207359

NIHMSID: NIHMS325035

The Alzheimer'south Questionnaire: A Proof of Concept Written report for a New Informant-Based Dementia Assessment

Marwan Northward. Sabbagh,^{a, *} Michael Malek-Ahmadi,^a Rahul Kataria,^a Christine Grand. Belden,^a Donald J. Connor,^a Caleb Pearson,^a Sandra Jacobson,^a Kathryn Davis,^a Roy Yaari,^b and Upinder Singh^c

Marwan N. Sabbagh

^aThe Cleo Roberts Center for Clinical Research, Banner Lord's day Wellness Research Found, Dominicus City, AZ, Us

Michael Malek-Ahmadi

^aThe Cleo Roberts Centre for Clinical Inquiry, Imprint Sun Wellness Research Plant, Lord's day City, AZ, USA

Rahul Kataria

^aThe Cleo Roberts Middle for Clinical Research, Banner Sunday Health Enquiry Institute, Sunday City, AZ, USA

Christine M. Belden

^aThe Cleo Roberts Heart for Clinical Inquiry, Imprint Sun Health Research Establish, Sun City, AZ, USA

Donald J. Connor

^aThe Cleo Roberts Heart for Clinical Research, Banner Sun Health Inquiry Institute, Sun City, AZ, USA

Caleb Pearson

^aThe Cleo Roberts Heart for Clinical Enquiry, Imprint Sunday Health Research Found, Lord's day City, AZ, United states

Sandra Jacobson

^aThe Cleo Roberts Middle for Clinical Enquiry, Banner Sun Health Enquiry Institute, Sun Metropolis, AZ, USA

Kathryn Davis

^aThe Cleo Roberts Center for Clinical Research, Banner Sun Health Enquiry Institute, Sunday Urban center, AZ, The states

Roy Yaari

^bBanner Alzheimer's Found, Phoenix, AZ, USA

Upinder Singh

^cSierra Health, Las Vegas, NV, USA

Abstract

The aim of this pilot study is to decide the feasibility and clinical utility of a brief, informant-based screening questionnaire for Alzheimer'southward illness (Advertizing) that can exist administered in a primary care setting. The Alzheimer's Questionnaire (AQ) was administered to the informants of 188 patients in 3 dementia clinics (l cognitively normal, 69 mild cerebral impairment (MCI), 69 Advertizement). Total score for the AQ is based upon the sum of clinical symptom items in which the informant responds as being present. Clinical symptoms which are known to be highly predictive of the clinical Ad diagnosis are given greater weight in the total AQ score. The mean time of administration of the AQ was 2.half dozen ± 0.6 minutes. Sensitivity and specificity were institute to be high for detecting both AD (98.55, 96.00) and MCI (86.96, 94.00) with ROC curves yielding AUC values of 0.99 and 0.95, respectively. This airplane pilot study indicates that the AQ is a cursory, sensitive measure for detecting both MCI and Advertising and could be easily implemented in a master care setting.

Keywords: Alzheimer'due south illness, instrument, questionnaire, main intendance

INTRODUCTION

Confidence in making the diagnosis of Alzheimer's disease (Advert) and balmy cognitive impairment (MCI) remains elusive. Evidence suggests that physicians, bombarded by demands of care past increasing numbers of medical conditions and available treatments, are non sufficiently sensitive to signs of cognitive damage or early on dementia.

Many physicians practise not screen for cognitive problems in their practices unless they receive complaints from either patients or patients' families [1–3]. This is unfortunate since a majority of patients with a dementing illness do not report cognitive problems to their health care providers and, on average, family unit members do not seek medical attention for the patient until several years after the onset of symptoms. As a result, recognition of dementia by master care physicians is poor until information technology is moderately advanced [three,iv]. Providers cite a lack of confidence in diagnosing Ad as a principal reason that nearly half of AD patients remain undiagnosed [1,five,6]. Delaying diagnosis results in increased likelihood of disease progression before intervention is attempted [vii]. Screening has been proposed to help combat nether-diagnosis simply validated, structured, interview based instruments are lacking. The desirable characteristics for a clinician-administered screening instrument include high sensitivity, loftier specificity, curt administration time, minimal training requirements for the musical instrument ambassador and simplicity of scoring [vii].

We take adult the Alzheimer's Questionnaire (AQ), a clinician-administered and informant-based screening instrument as a way to speedily and accurately detect cognitive harm. Scores for some items are weighted based on their ability to accurately predict the clinical AD diagnosis which is fabricated based on the results from other validated instruments. The AQ offers the advantage of request unproblematic yeah/no questions in a weighted format that gives an absolute score without requiring interpretation of individual domains. This will help clinicians in request the most pertinent questions when screening for cognitive decline in the primary care setting [2].

METHODS

Development of the AQ

Items for the AQ are based on those from other widely used informant-based assessments [8,10–12], merely take been adapted for ease and speed of assistants. Items for the AQ were selected and approved by a group of clinicians with extensive feel in dementia assessment. The items were selected based on their face validity to assess each of the AQ domains. Six items were selected to be weighted in the AQ total score as it was agreed by the clinicians that these items would conspicuously differentiate an impaired private from a cognitively normal individual.

Written report participants

The Advert and MCI subjects were drawn from the practices of iii physicians (MS, RY, The states). The cognitively normal (NC) subjects were administered the AQ as part of their annual assessment for a brain donation program as all are required to provide a collateral informant. Since this is a data gathering project, an IRB exemption was granted.

Included in the report were 188 subjects, l of which were designated NC, 69 were MCI cases, and 69 were AD cases. The Ad subject met NINCDS-ADRDA [thirteen] criteria for a clinical diagnosis of probable and possible AD. Our NC subjects were divers as having no demonstrable cognitively-based limitations of activities of daily living including employment by informant report. MCI cases were diagnosed as such based on Petersen criteria [xiv]. Consensus diagnosis with a neurologist, geriatric psychiatrist, and neuropsychologist was used to determine the clinical status of each subject. Rigorous criteria were used to exclude anyone with any type of symptomatic or severe brain related neurological or psychiatric illness. Excluded weather condition included mental retardation, epilepsy, cerebral infarction or hemorrhage, multiple sclerosis, brain tumor, major depressive disorder (unipolar or bipolar), schizophrenia, traumatic brain injury, and substance abuse. This was done by prospective interview of the participant and careful scrutiny of the medical records. Each bailiwick was asked to identify an informant to provide additional information on cognitive and functional changes.

Administration of AQ

The AQ consists of elementary yes/no questions in a weighted format pertaining to five domains which are: Memory, Orientation, Functional Power, Visuospatial and Linguistic communication (Table 7). Points for each question that are answered "yes" are summed to give a total score. Each discipline was accompanied past the informant to a clinic, where the AQ was administered to the informants of sequent patients.

Appendix 1

The Alzheimer'southward Questionnaire

	Yeah	No	Weighted Score
Memory
Does the patient have memory loss?			1
If so, is their memory it worse than a few years ago?			1
Does the patient echo questions OR statements OR stories in the same mean solar day?			2
Take you had to take over tracking events OR appointments? OR Does the patient forget appointments?			1
Does the patient misplace items more than than once a month? OR Does the patient misplace objects so that he or she cannot notice them?			1
Does the patient suspect others are moving, hiding or stealing items when they cannot observe them?			1
Orientation
Does the patient frequently have trouble knowing the mean solar day, date, month, year, time? OR Does the patient take to use cues similar the paper or the calendar to know the 24-hour interval and engagement more than one time a 24-hour interval?			ii
Does the patient become disoriented in unfamiliar places?			1
Does the patient become more dislocated outside the home or when traveling?			1
Functional Ability
Excluding concrete limitations (east.g., tremor, hemiparesis, etc.), does the patient have trouble handling money (tips, calculating change?)			1
Excluding physical limitations (e.k., tremor, hemiparesis, etc.), does the patient have trouble paying bills or doing finances OR Are family unit members taking over finances because of concerns about ability?			2
Does the patient take trouble remembering to take medications or tracking medications taken?			1
Is the patient having difficulty driving? OR Are you concerned near the patient's driving? OR Has the patient stopped driving for reasons other than concrete limitations?			1
Is the patient having problem using appliances (e.thou., microwave, oven, stove, remote control, telephone, alarm clock)?			1
Excluding concrete limitations, is the patient having difficulty in completing dwelling house repair or other habitation related tasks (housekeeping)?			1
Excluding concrete limitations, has the patient given up or significantly reduced activities such every bit golfing, dancing, exercising, or crafts?			one
Visuospatial
Is the patient getting lost in familiar surroundings (own neighborhood)?			2
Does the patient accept a decreased sense of direction?			one
Language
Does the patient have trouble finding words other than names?			ane
Does the patient confuse names of family unit members or friends?			2
Does the patient have difficulty recognizing people familiar to him/her?			2

Statistical analysis

The data were analyzed by showtime evaluating the sensitivity and specificity of the AQ with regard to identifying both MCI and Advertizement cases. The accuracy of the AQ was so analyzed past using receiver operating characteristic (ROC) curves and their associated area under the curve (AUC) value. The psychometric properties of the AQ were then analyzed through a main component factor analysis and by Cronbach'southward alpha which assessed the AQ's internal validity. In add-on, correlations of the AQ domain scores were also derived in order to demonstrate internal validity. Analysis of covariance (ANCOVA) was also used to discern statistically significant group differences in AQ scores between the three clinical groups.

RESULTS

The AQ was administered to the informants 188 subjects. Individuals with Mini-Mental Condition Exam (MMSE) scores below 20 were excluded in lodge reduce the amount of overall variability in the data and so that the data better reflected a population that is likely to exist seen in a main care setting for cognitive complaints. The sample consisted of 45.7% (n = 86) females and 54.3% (n = 102) males. Detailed demographic characteristics are displayed in Tabular array 1. The mean time of administration of the AQ was 2.6 ± 0.6 minutes.

Table ane

Demographic Characteristics of Written report Sample

	NC	MCI	Advertizement	Full
North	50	69	69	188
Hateful Age (sd)	77.lx (seven.33)	74.61 (7.71)	78.68 (7.21)	76.90 (seven.61)
Mean Education (sd)	fifteen.48 (2.85)	14.61 (2.60)	14.52 (2.57)	14.81 (2.67)
Mean MMSE (sd)	28.86 (1.31)	27.28 (ane.99)	24.09 (2.50)	26.53 (2.83)
Mean AQ Score (sd)	2.12 (ii.31)	eleven.06 (5.12)	17.64 (4.84)	11.10 (7.53)

Sensitivity and specificity of the AQ were plant to be high for detecting both MCI and Advertizement. In addition, ROC curve analysis yielded high AUC values. Values for sensitivity, specificity, and AUC are displayed in Table 2. Graphical representations of the ROC analyses are displayed in Figs 1 and ​ two. Internal validity of the AQ was determined to exist high as Cronbach's blastoff was equal to 0.88. Cistron analysis was conducted using the principal component analysis method and showed that all 21 items on the AQ loaded strongly onto ane factor which accounted for 33.26% of the total variance with an Eigen value of 6.98.

ROC Bend for MCI (AUC = 0.95).

ROC Curve for NC versus AD (AUC = 0.99).

Tabular array two

Sensitivity, Specificity, and AUC of the AQ

	Sensitivity (95% CI)	Specificity (95% CI)	AUC (95% CI)
MCI	86.96 (76.70–93.xc)	94.00 (83.l–98.7)	0.95 (0.90–0.98)
AD	98.55 (92.xx–100.00)	96.00 (86.30–99.50)	0.99 (0.96–one.00)

Correlations between the domain scores of the AQ were also evaluated to further demonstrate internal validity and are shown in Table 3. All correlation values are significant at the p < 0.0001 level. Analysis of covariance (ANCOVA) was used to analyze grouping differences on the AQ. After bookkeeping for the effects of age and education, statistically significant differences on hateful AQ score were nowadays between all three clinical groups [F = 177.85 df = (2, 185), p < 0.0001].

Tabular array iii

Correlation of AQ Domain Scores

Domain	Memory	Orientation	Functional power	Visuospatial	Language
Memory	———	0.80	0.82	0.55	0.64
Orientation	0.fourscore	———	0.81	0.59	0.63
Functional Ability	0.82	0.81	———	0.59	0.66
Visuospatial	0.55	0.59	0.59	———	0.41
Language	0.64	0.63	0.66	0.41	———

A separate analysis of the data was conducted with the weights removed from the weighted items. In general, removing the weights did not change sensitivity, specificity, and AUC values (Table 4). Correlations amid the AQ domain scores were like to those institute with weighted scores (Table 5). However, the Linguistic communication domain had notable increases in its correlations with Memory, Orientation, and Functional Power in the unweighted analysis. In add-on, the factor analysis results were nearly identical to those of the weighted analysis and Cronbach's blastoff was slightly higher (0.89) for the unweighted analysis.

Tabular array four

Sensitivity, Specificity, and AUC of the AQ With Unweighted Items

	Sensitivity (95% CI)	Specificity (95% CI)	AUC (95% CI)
MCI	87.14 (77.00–93.xc)	92.73 (82.twoscore–98.00)	0.94 (0.89–0.98)
AD	95.65 (87.80–99.10)	98.18 (xc.30–100.00)	0.99 (0.96–1.00)

Table 5

Correlation of AQ Domain Scores with Unweighted Items

Domain	Retentiveness	Orientation	Functional power	Visuospatial	Linguistic communication
Retention	———	0.lxxx	0.81	0.63	0.66
Orientation	0.80	———	0.80	0.65	0.64
Functional Power	0.81	0.eighty	———	0.62	0.68
Visuospatial	0.63	0.65	0.62	———	0.44
Language	0.66	0.64	0.68	0.44	———

In addition, several items on the AQ that appeared to be like with respect to content and construct were identified and analyzed to determine if whatever of the items should be eliminated. These consisted of 6 questions amidst three of the domains. Each domain contained two questions that were identified for further analysis. Kappa statistics were calculated for each pair of questions to determine the extent to which they were answered similarly.

For the Orientation domain, "Does the patient become disoriented in unfamiliar places?" and "Does the patient get more dislocated when travelling outside the dwelling?" yielded a Kappa of 0.34 (0.01, 0.67). For the Visuospatial domain, "Is the patient getting lost in familiar surround?" and "Does the patient have a decreased sense of management?" yielded a Kappa of 0.34 (0.05, 0.62). For the Linguistic communication domain, "Does the patient confuse names of family members or friends?" and "Does the patient accept difficulty recognizing people who are familiar to him/her?" yielded a Kappa of 0.34 (0.01, 0.67).

Give-and-take

Two important and conclusive findings are highlighted within the present study. First, the AQ is a sensitive measure for detecting both AD and MCI. Second, the AQ is a time-efficient and hands administered tool with a elementary scoring organization. As the time taken to administrate AQ is less than iii minutes, making information technology easy to implement in a chief care setting to screen for cognitive problems. The simplicity of the AQ is reflected in that the total score is easily calculated by summing the number of items that have a "yes" response.

The rationale for weighting certain items on the AQ is that they reflect the presence of cognitive symptoms which are known to be highly predictive of the clinical Ad diagnosis, such as disorientation to time (east.g., day of the calendar week, month) and repeating statements and questions within a short period of time [15]. This differentiates the AQ from other informant-based instruments that give equal weight to all of their items every bit information technology is then problematic to accurately differentiate cognitive symptoms that are related to AD versus normal aging. The effect of utilizing weighted scores for those items that are highly predictive of clinical AD is that high diagnostic accurateness, as demonstrated by the sensitivity, specificity, and ROC curves, is achieved which strongly supports the clinical validity of AQ. In improver, this study also demonstrated high internal validity of the AQ through factor analysis and also with a loftier Cronbach's alpha. Specifically, the factor analysis shows that the items of the AQ accurately assess memory and other cognitive components that are indicative of MCI and Ad.

Analyses of the data without the weights showed no pregnant differences among the statistical measures; however the inclusion of weights on sure items appears to optimize sensitivity and overall diagnostic accuracy for Advertizing. The unweighted analysis also showed an increase in correlation values among certain domains. Specifically, the Language domain showed increased correlations with Memory, Orientation, and Functional Ability. The reason for this is unclear, only it is possible that removing the weights simply made the data fit a more linear blueprint. In improver, questions that appeared to be overlapping in construct measurement did non overlap as shown by the depression rate of understanding within the question pairs in each domain. Although these items announced to be similar, they are measuring distinct phenomena.

Although several other informant-based dementia questionnaires have been developed, they take not been validated equally accurate instruments in detecting individuals with MCI. This is of import as identifying individuals in the earliest stages of cognitive decline will exist necessary as the evolution of disease-modifying therapies become available. Currently-used instruments that are clinician administered such equally the MMSE [sixteen, 17], the neurobehavioral cognitive test [eighteen], the 7 minute screen [xix], the time and change examination [20], the memory damage screen [21], the clock drawing test [22], and the mini-cog [23] have demonstrated relatively adept diagnostic ability in Ad patients. However, the ability of these instruments to identify individuals with MCI is questionable.

In addition, currently used informant-based instruments accept non been shown to accurately identify individuals with MCI. The well-nigh common clinician-administered [16–23] and informant-based [8–12,24–26] instruments accept demonstrated specificities and sensitivities exceeding 80% in identifying Advertising cases and all take less than 10 minutes to administer. Relative to the most widely used of these instruments, the AQ has higher sensitivity and specificity with regard to identifying AD cases (Table 6), simply besides high sensitivity and specificity in identifying MCI. In addition, its administration time is comparable and in many cases takes less time to administrate.

Table six

Comparing of AQ Performance with AD8 and IQCODE in AD

Instrument	Sensitivity	Specificity	AUC	Cronbach's blastoff
AQ	98.55	96.00	0.99	0.88
AD8	85.00 [viii]	86.00 [8]	0.83 [8]	0.86 [25]
IQCODE	79.00 [26]	82.00 [26]	0.85 [26]	0.93–0.97 [9]

It is important to note that the AQ is not intended to supplant a full diagnostic piece of work-up that is typically done when assessing individuals with retentiveness issues. It should as well be noted that the AQ was not used in a general do setting and so it is unclear whether the results of this report represent that of the full general geriatric population. This study utilized patients who were seen by dementia specialists and as a consequence the sample used is biased to a certain extent. Although the ultimate goal is to employ this instrument in general practice, it was employed in specialty practices during this airplane pilot study. In spite of these shortcomings, the AQ may exist an extremely useful tool to clinicians who require the utilize of a brief and accurate assessment of cognition in lodge to determine if a patient might require further evaluation. Given its diagnostic accuracy, ease of scoring, ease of assistants, and short length of time needed for administration the AQ would be of great value to many clinicians who have an extremely limited amount of time in order to assess individuals with memory and cognitive problems.

Acknowledgments

Supported by the Banner Sun Health Inquiry Plant, NIA P30 AG 019610, ADHS AGR 2007-37, Arizona Alzheimer's Enquiry Consortium, and Imprint Alzheimer's Institute.

This written report was funded past the Arizona Alzheimer'south Research Consortium. The Consortium had no other function other than to provide financial support for the project.

Footnotes

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