Donepezil, rivastigmine, galantamine and memantine for ...

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Economic analysis
classification system, the issues of ‘goodness of fit’,
as the two health descriptions used have distinct
differences. For example, (1) where the EQ-5D
classifies usual activities the Odense Study refers to
ability to perform ‘hobbies’ in the home; (2) where
the EQ-5D states ‘unable to wash or dress myself ’,
the Odense Study states ‘unable to wash or dress
without help’, and these descriptions may contain
subtle, yet important, differences; (3) where
patients in the Odense study refer to a poor
assessment of own health status it appears that this
is mapped to an EQ-5D point of extreme pain or
discomfort. The use of a Danish EQ-5D tariff
detracts from the generalisability of the data to a
UK setting.
The source for the mortality data used in the
model is cited as the LASER-AD Study 146 but the
data used are not reported in the published paper;
6-monthly rates of 3.1, 7.1 and 18.8% are used in
the model for mild–moderate, moderate–severe
and severe AD, respectively.
The model does not include dropouts in the
disease progression process, stating that this is a
conservative assumption (not favouring the use of
memantine) as trial data reported higher dropouts
for placebo compared to memantine treatment.
Costing considerations in the
treatment of AD
Identifying cost burdens
As highlighted in the earlier report to NICE, 1 the
evaluation of AD treatment involves a number of
different provider and funding sectors, and
consideration of the various costs for treatment
and who will be responsible for funding such
treatment is an important issue. The primary
perspective for this report (and for the NICE
appraisal process) is that of the NHS and PSS, but
other areas of expenditure are relevant in the
overall treatment of AD. Table 55 outlines the main
sectors or components of care/funding in England
and Wales for those involved in caring for people
with AD.
In England and Wales, establishing the setting of
care and the relevant funding source is not always
straightforward, as patients and carers often
contribute to the cost of care, whether
institutionalised or not. For example, in the UK,
patient-related private funding and social security
transfer payments accounted for more than 75%
of the costs for patients with advanced cognitive
impairment in private households and
private/voluntary residential or nursing homes
(based on a 1993 report, and subsequent changes
in funding affect this funding profile). 119
AD treatment and management costs
In consideration of the costs associated with AD,
the key areas, from the perspective of the NHS
and PSS, are therapy costs (e.g. drug costs,
monitoring) and on-going cost of care for patients
by residential setting [i.e. at home, in the
community and/or in an institutional setting
(residential care homes and nursing homes)].
Other private patient costs and resources
associated with informal carer input for AD
patients are also important issues from a patient
or societal perspective; however, these are not the
prime focus of this report, although where
possible these cost inputs are highlighted.
The expected therapeutic costs are outlined below
with discussion of the literature to inform on the
longer term costs for AD patients by setting of
care (residential status). The focus is on the UK
literature, although a large international literature
is also available to inform on these issues in a
broader context (e.g. see review by Bloom and
colleagues 149 ).
Therapeutic costs for pharmaceuticals
Product costs
Table 56 reports the cost per year for each of the
drugs (by dose). These costs are based on list
prices presented in the BNF (No. 49), 150 and do
not include any handling or prescriptions costs,
nor do they reflect any purchasing discounts which
may be available for specific funding agencies.
Monitoring costs
AD patients are managed in a number of ways,
either through general practice or through
hospital clinics, or a combination of the two, more
recently in a shared-care approach. Following
discussions with treating physicians, the additional
management cost for patients on drug therapy
versus non-drug therapy are thought to be limited
to the additional 6-monthly follow-up visits
recommended by NICE in their guidance of
2000. 30 Analysis by the present reviewers included
two additional outpatient appointments per year,
at £108 each, 151 as an additional monitoring cost.
Literature on costs associated with
treatment for AD
The literature on the cost of care for AD in the
UK is not extensive. Costing studies are a
combination of burden of illness studies, using
aggregate data on costs and prevalence, 126,152 and