Department of Clinical Epidemiology and Medical Technology Assessment, University Hospital, and Department of Psychiatry & Neuropsychology, Maastricht University
Department of Clinical Epidemiology and Medical Technology Assessment, University Hospital, Maastricht
Department of Clinical Epidemiology and Medical Technology Assessment, University Hospital, and Department of Health Organisation, Policy & Economics, Maastricht University
Department of Psychiatry & Neuropsychology, Maastricht University, Maastricht, The Netherlands
Correspondence: Professor F. R. J. Verhey, Department of Psychiatry and Neuropsychology, University Hospital of Maastricht/Alzheimer Centre Limburg, PO Box 5800, 6202 AZ Maastricht, The Netherlands. Email: f.verhey{at}np.unimaas.nl
None. Funding detailed in Acknowledgements.
|
|
|---|
An integrated multidisciplinary approach to dementia is often recommended but has rarely been evaluated.
Aims
To evaluate the clinical effects of an integrated multidisciplinary diagnostic facility for psychogeriatric patients.
Method
Patients suspected of having complex psychogeriatric problems were randomly allocated to the intervention (n=137) or to treatment as usual (n=93). They were assessed at baseline, and at 6 months and 12 months follow-up by means of personal interviews with the patient's proxy. The primary outcome was health-related quality of life, assessed using the visual analogue scale (VAS) of the EuroQd measure, EQ–5D.
Results
Health-related quality of life had improved at 6 months in the intervention group, whereas that of the control group had decreased. Furthermore, more patients in the intervention group experienced a clinically relevant improvement of 10 points or more on the VAS at both follow-up measurements.
Conclusions
An integrated multidisciplinary approach improves dementia care.
|
|
|---|
The Maastricht Evaluation of a Diagnostic Intervention for Cognitively Impaired Elderly (MEDICIE) study is a randomised controlled trial comparing the efficacy and efficiency of DOC–PG and usual care. We predicted that the DOC–PG intervention would have beneficial effects on health-related quality of life (HRQoL) compared with usual care, based on the assumption that both diagnosis of the cognitive disorder according to specialist guidelines and appropriate assessment of the patient's social circumstances are prerequisites for the best possible care for the patient and the patient's family. The trial registration number is NCT00402311.
|
|
|---|
Study participants
The MEDICIE study was approved by the medical ethics committee of
Maastricht University Hospital. Patients were recruited from July 2002 to
August 2004 from 60 general practices in the Maastricht region, 7 practices in
the Sittard region and 3 practices in the east Heerlen region (all three
regions are in the province of Limburg, in the south of The Netherlands).
General practitioners in these practices were asked to refer all patients with
possible dementia or a cognitive disorder. The inclusion criteria were age 55
years or older; a suspected diagnosis of dementia or a cognitive disorder; no
referral to other local or regional services in the past 2 years and
availability of a proxy (visiting the patient at least once a week). Exclusion
criteria were the presence of an acute disorder requiring prompt therapeutic
intervention, and living in a nursing home.
Randomisation
Randomisation took place at the practice level to prevent contamination at
a patient and general practitioner level. In order to control for effects
related to differences in general practices, all practices were asked to
supply information about the practitioner's experience, demographic
characteristics of the practice population, and the practitioner's affinity
with geriatric problems. On the basis of these data two groups of practices
were formed, and the patients from these practices were randomly assigned (by
means of a computer program) to either the intervention group or the control
group (usual care). The general practitioners were initially masked to this
procedure and the random allocation sequence was concealed for most of the
participants.
Interventions
DOC–PG
The DOC–PG has expertise in the fields of old age psychiatry,
geriatric medicine, neuropsychology, physiotherapy, occupational therapy,
geriatric nursing and mental health nursing, and hence enables
multidisciplinary assessment of patients, covering aspects such as somatic
screening, psychogeriatric assessment, and evaluation of the required levels
of care for patients and their carers. General practitioners can refer
patients to the DOC–PG if a cognitive disorder is suspected. During a
2-week diagnostic screening procedure, patients are visited once at home and
are asked to visit the university hospital departments of geriatric medicine
and geriatric psychiatry. A computed tomographic scan and various blood tests
are performed. The results are then discussed at a weekly interdisciplinary
meeting in which a definite diagnosis is made and a treatment plan is
formulated. The patient's general practitioner is sent a summary of the
assessments, the multi-axis diagnosis and recommendations for treatment and
management; thereafter the general practitioner is responsible for the patient
even though further investigations might have been recommended.
Usual care
In the control group general practitioners provided care as usual. This
means that the patients were not referred to the DOC–PG and that either
the diagnosis was made by the general practitioner or the patient was referred
to one of the separate regional services, such as the Maastricht Memory
Clinic, geriatric medicine or the department of mental health for the elderly
at the mental health community
service.5
Outcome measures
Interviewers, who for practical reasons could not be kept totally unaware
of the treatment assignment, assessed participants at baseline (within 2 weeks
of the DOC–PG or usual care intervention) and at 6 months and 12 months
after the baseline measurement. All outcome measures (except the Mini-Mental
Scale Examination (MMSE)) were collected through personal interviews with the
patient's proxy (i.e. we measured the proxy's perception of the patient's
health). The HRQoL of the patient and the carer was the primary outcome of
this study. Because we expected that the patients would show a complex range
of mental, physical and social problems, we chose to use the EQ–5D to
measure HRQoL. This instrument has been validated in a number of European
countries including The
Netherlands8 and
provides a simple descriptive profile and a single index value for health
status. It is widely used in cost–utility
analyses.9,10
The EQ–5D consists of a scale, VAS, ranging from 0 (worst imaginable
health state) to 100 (best imaginable health state). Change in VAS scores over
the course of 1 year was the primary outcome variable in this study. A
difference of 10% or more between the intervention group and the control group
on the VAS was a priori considered to be a clinically relevant
difference, as described in the original protocol that preceded the start of
the study. The number of patients experiencing this clinically relevant
difference were compared between both groups.
As the secondary outcome instrument we used the 36-item Short Form Health Survey (SF-36),11 a generic questionnaire used to measure nine relevant aspects of the health-related functioning of patients. Higher scores reflect better functioning.11–13 Additional secondary outcome measures were scores on the MMSE,14 the Global Deterioration Scale (GDS),15 the Neuropsychiatric Inventory (NPI),16,17 the Instrumental Activities of Daily Living scale (IADL),18 and the Cornell Scale for Depression in Dementia (CSDD).19,20 The MMSE assesses the severity of cognitive decline, the GDS evaluates seven stages of global functioning in patients with a primary degenerative dementia such as Alzheimer's disease and the NPI appraises patients' behavioural and psychological problems. The IADL scale measures seven areas of more complex activities required for optimal independent functioning, with scores reflecting whether patients are completely independent, are in need of assistance, or are completely dependent on others for the performance of specific activities.18 The CSDD is a 19-item depression scale that was developed specifically to measure the severity of depressive symptoms in older adults with dementia. Higher scores on all instruments, except for the MMSE, are indicative of more severe problems.
Statistical analyses
Missing data
Missing items were imputed using a regression model, and missing data or
data missing covariates were imputed using Rubin's multiple imputation
procedure.21 This
method generates ten different data-sets for imputed data. All analyses were
performed with each of these ten data-sets and the results were pooled.
Complete missing data were imputed if participants had completed the
instrument on two occasions but not if they had completed only the baseline
measurement. These patients were considered as having withdrawn from the
study. With a logistic regression analysis the probability of withdrawing from
the study was assessed and, with these probabilities, P weights were
calculated as 1/(1–predicted probability). This allowed for differential
weighting of people in data
analysis.22 The
data of patients who had died after the baseline measurement and before the
follow-up investigations were not analysed.
Data analysis
Weighted regression models, clustered on general practice level, were used
to examine the influence of group (intervention or usual care) on outcome on
each of the instruments. The cluster option was used to account for the
correlated data within general practices. The dependent variables in the
models were the scores and the change over time of the participants' scores on
the instruments, with baseline characteristics (group, gender, age, diagnosis
and MMSE score) as independent variables. The software SPSS version 12.0.1 for
Windows was used to calculate the P-weights, to examine group
differences and to impute the missing items by means of a regression model
(missing value analysis). Rubin's multiple imputation procedure and our main
regression analyses were performed using Stata version 8.2 for Windows. The
background characteristics of the participants (both the patients and their
proxies) were summarised using descriptive statistics. Response distributions
of the instruments are provided.
|
|
|---|
![]() View larger version (20K): [in a new window] [as a PowerPoint slide] |
Fig. 1 Flow of patients through trial. DOC–PG, Diagnostic Observation Centre
for Psychogeriatric Patients
|
|
View this table: [in a new window] |
Table 1 Baseline characteristics of the sample
|
Outcomes
The mean score on the social functioning component of the SF–36 was
significantly higher (P=0.03) in the intervention group than in the
usual care group at 6 months (Table
2); no other difference in mean scores was found between the
groups. The mean difference scores for the EQ–5D over time were
significantly different between the two groups (P=0.04).
Health-related quality of life measured with the VAS improved slightly in the
intervention group (1.5 points) but decreased in the usual care group (4
points). We found a mean group difference of 9.6% in VAS after 12 months,
which was close to our initial expectations. The proportion of patients who
improved more than 10% (of the group difference) on the VAS was significantly
greater (P=0.01) in the intervention group (39.0%) than in the
control group (22.1%). With an improvement of 0.03 on the population utility
score of the EQ–5D being considered a clinically relevant
improvement,23
significantly (P=0.04) more patients in the intervention group than
in the usual care group showed a clinically relevant improvement after 6
months (42.1% v. 37.7%). Furthermore, the groups differed
significantly (P=0.02) on the change score in the social functioning
component of the SF–36, with patients in the intervention group showing
a larger improvement than patients in the usual care group. After 12 months,
more patients in the intervention group than in the usual care group showed a
clinically relevant improvement in HRQoL measured as an improvement of more
than 10% of the group difference on the VAS (32.6% v. 18.6%,
P=0.01) and on the utility score of the EQ–5D (40.6%
v. 24.7%, P<0.0001). The groups did not differ in terms
of clinical outcome measures (Table
3).
|
View this table: [in a new window] |
Table 2 Health-related quality of life outcomes at follow-up and results of
regression analyses (group differences)
|
|
View this table: [in a new window] |
Table 3 Clinical outcomes at follow-up and results of regression analyses (group
differences).
|
We investigated whether these differences in HRQoL between the groups were related to the use of cholinesterase inhibitors, in a post hoc analysis. In general, few patients received cholinesterase inhibitors (mean 14.6%), but significantly more patients in the intervention group than in the usual care group were treated with these drugs (18.3% v. 9.1%, P=0.01). However, the use of cholinesterase inhibitors had no influence on the proportion of patients who showed a clinically relevant improvement in HRQoL after 6 months (P=0.15) and after 12 months (P=0.53).
|
|
|---|
The similarity of outcomes other than HRQoL in the two groups might be because the intervention provided access to two healthcare facilities that were available to the usual care group. Whereas medical centres tend to focus on medical diagnostics and pharmacotherapy, community mental health services focus on the provision of appropriate levels of care and support for patients and their carers. It is thus not surprising that the two approaches had comparable effects on psychological and behavioural problems, emotional functioning and ability to manage daily life. In this context, usual care in our region is very good and is provided by an active university medical centre and a community mental health service that have collaborated in the past on several projects. Thus, the contrast between DOC–PG and usual care might have been smaller than would be the case in other regions.
To our knowledge, this is the first randomised controlled trial of a multidisciplinary diagnostic approach to dementia. Our results suggest that an integrated approach to dementia as recommended by international dementia guidelines improves patient outcomes. In the absence of a cure for dementia, the finding that (the proxy perception of) HRQoL can be improved with an integrated treatment plan formulated on the basis of a multidisciplinary diagnostic evaluation is important. It should, however, be noted that the results of this study cannot be generalised to nursing-home care.
The study had potential weaknesses. First, the design of the study was not optimal because it was not feasible to mask the interviewers assessing the patients and their carers to the treatment assigned. However, all instruments were standardised and the participants received neutral instructions for every instrument. Another potential problem is linked to our inability to keep the random allocation sequence completely concealed, because the person responsible for the allocation of patients also recruited a small number of patients (5%). However, the people who recruited the majority of the patients were unaware of patient allocation. The masking of the referring general practitioners could not be maintained until the end of the study. In order to investigate the potential effects of this on the study results, we compared post hoc the characteristics of patients in the two groups who were recruited in the first year and in the second year. We did not find any difference within the intervention group with respect to age, gender, diagnosis, MMSE score and GDS score; however, there were non-significant differences in diagnosis and GDS score in the control group – in the second year of the inclusion period more people with a cognitive disorder other than dementia and with a lower GDS score were included. The general practitioners probably wanted to refer patients to DOC–PG but this was only possible after recruitment was completed. The inclusion of slightly healthier patients (with consequently higher quality of life and lower costs) in the latter half of the inclusion period probably resulted in a less favourable outcome for the DOC–PG intervention. Another potential limitation is the use of proxies to complete the questionnaires. We chose to use proxies because of the longitudinal nature of the study, the complex health problems of the study population and the anticipated progressive global deterioration of intellect and personality of the study population. In the later stages of dementia, proxy measures are generally considered necessary because patients are no longer able to evaluate their own health.25,26 The proxy scores on the various instruments might have been biased because of a perceived caregiver burden,27 but this bias would apply to both groups. Furthermore, it should be emphasised that we measured the proxy's perception of the HRQoL of the patient rather than a direct estimate of HRQoL. Another problem is the presence of missing data, which could have affected the statistical analyses. However, very few data (5%) were missing, and multiple imputation procedures provide a useful strategy for dealing with data-sets with missing values. Instead of filling in a single value for each missing value, the missing value is replaced by a set of ten plausible values that represent the uncertainty with respect to choosing the right value to impute. This results in statistically valid inferences that properly reflect the uncertainty brought on by missing values.21,28
We chose the VAS of the EQ–5D as main outcome because it has good clinimetric properties, is reliable29 and is easy to administer. Unfortunately, the VAS is more subjective than the descriptive component of the EQ–5D and this could be considered a limitation. A person's state of mind, goals and expectations can influence VAS scores;30,31 however, we expected that these effects would be present in both groups. Moreover, the VAS enables a personal valuation of the patient's HRQoL, which is an important outcome in the absence of a cure.
There is a growing interest in studies on effectiveness and efficacy of multidisciplinary healthcare models. We are currently conducting an economic evaluation comparing the costs of DOC–PG and of usual care. Although a multidisciplinary model is more effective than a monodisciplinary model, it is also more complex, requiring a higher level of organisation. It is therefore a challenge for clinicians to combine their professional expertise and share responsibility for a patient given their different – and sometimes opposing – approaches and views on patient care and management. For instance, the role of memory clinics is debated. Although some claim that these clinics merely prescribe and monitor drug treatment,32 such clinics are becoming increasingly integrated in the standard care for dementia in The Netherlands.33 We recommend that all services involved with dementia care integrate (such as in the DOC–PG) rather than polarise, because greater integration will lead to greater continuity of care for patients with dementia. The value of DOC–PG has already been recognised by general practitioners, as evidenced by the high referral rate by these doctors and by the high compliance with DOC–PG recommendations.24
|
|
|---|
The study was funded by the Dutch Research Institute for Care – Medical Sciences (ZorgOnderzoek Nederland-Medische wetenschappen), grant 945-02-055.
|
|
|---|
Related articles in BJP:
This article has been cited by other articles:
![]() |
R. Melis, E. Meeuwsen, S. Parker, and M. Olde Rikkert Are memory clinics effective? The odds are in favour of their benefit, but conclusive evidence is not yet available J R Soc Med, November 1, 2009; 102(11): 456 - 457. [Full Text] [PDF] |
||||
![]() |
C. A. G. Wolfs, C. D. Dirksen, A. Kessels, J. L. Severens, and F. R. J. Verhey Economic Evaluation of an Integrated Diagnostic Approach for Psychogeriatric Patients: Results of a Randomized Controlled Trial Arch Gen Psychiatry, March 1, 2009; 66(3): 313 - 323. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Tyrer From the Editor's desk The British Journal of Psychiatry, March 1, 2009; 194(3): 292 - 292. [Full Text] [PDF] |
||||
![]() |
S. V. McNulty, G. A. Jackson, and A. J. Pelosi Integrated multidisciplinary diagnostic approach for dementia The British Journal of Psychiatry, September 1, 2008; 193(3): 257 - 257. [Full Text] [PDF] |
||||
![]() |
A. Jha Integrated multidisciplinary approach for dementia care The British Journal of Psychiatry, July 1, 2008; 193(1): 79 - 79. [Full Text] [PDF] |
||||
![]() |
R. Butler The carers of people with dementia BMJ, June 7, 2008; 336(7656): 1260 - 1261. [Full Text] [PDF] |
||||
Read all eLetters
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||