Cost effectiveness of memantine in Alzheimer's disease in the UK

Figures & data

Figure 1. Model design.

Table 1.  Predictive equation parameters at baseline.

	Standard care
	Mean	SE
ADAS-cog baseline	36.30	1.70
ADCS–ADL baseline	45.00	1.87
NPI baseline	18.54	1.86
ADAS–cog slope	0.6116	0.0809
ADCS–ADL slope	−0.7503	0.0876

Table 2.  Treatment effect with memantine, results of the meta-analysis of six pivotal RCTs.

Domain	Weighted mean difference (WMD), SE
Cognition^†	−1.54 (0.31)
Functioning*	1.53 (0.62)
Behavioural^†	−1.34 (0.93)

*Positive score/^†negative score indicates improvement of a clinical outcome with memantine.

Table 3.  Monthly resource use and costs by pre-FTC and FTC state.

Resource	Unit	Unit cost	Monthly utilisation of the resource (mean ± SE)
			Pre-FTC (n = 48)	FTC in community (n = 29)	FTC in institution (n = 69)
General practitioner	Contact	£35	0.81 ± 0.42	0.34 ± 0.06	0.29 ± 0.05*
Practice/district (community)	Contact	£26	0.24 ± 0.09	0.40 ± 0.14	0.18 ± 0.08*
Community psychiatric nurse/case manager	Contact	£27	0.25 ± 0.17	0.13 ± 0.05	0.05 ± 0.03*
Psychiatrist	Contact	£126	0.17 ± 0.02	0.10 ± 0.04	0.13 ± 0.06*
Psychologist	Contact	£62	0.01 ± 0.01	0.05 ± 0.04	0.06 ± 0.06*
Social worker	Contact	£116	0.10 ± 0.04	0.07 ± 0.03	0.08 ± 0.02*
Occupational therapist	Contact	£72	0.02 ± 0.02	0.03 ± 0.02	0.07 ± 0.06*
Home help/care worker	Contact	£12	6.92 ± 2.39	14.07 ± 4.80	0.72 ± 0.52*
Voluntary worker	Contact	£18	0.06 ± 0.04	0.47 ± 0.23	0.17 ± 0.13*
Meals-on-wheels	Contact	£3	0.76 ± 0.49	1.86 ± 1.30	0.00 ± 0.00*
Physiotherapy	Contact	£42	0.01 ± 0.01	0.03 ± 0.03	0.09 ± 0.06*
Podiatrist/chiropodist	Contact	£34	0.19 ± 0.04	0.17 ± 0.04	0.39 ± 0.12*
Audiologist	Contact	£68	0.02 ± 0.01	0.01 ± 0.01	0.00 ± 0.00*
Day centre	Day	£35	3.42 ± 0.82	5.37 ± 1.35	1.86 ± 0.64*
Day respite/sitting	Day	£87	2.93 ± 1.89	2.00 ± 1.04	0.01 ± 0.01*
Day hospitalisation	Day	£281	0.63 ± 0.37	0.87 ± 0.52	8.97 ± 1.63
Institution/nursing home	Week	£575	0	0	3.00 ± 0.23

*For FTC patients residing in institutions, the indicated resources were assumed to be accounted in the cost of institutional care and were not included in calculation of the cost per state.

Table 4.  Base-case model results.

Outcome	Standard care	Memantine	Difference
Deterministic analysis (mean)
Cost, £, 2008/2009 (€)	£94,787	£93,076	−£1711
	(€114,143)	(€112,082)	(–€2060)
Time in pre-FTC state	19.8 months	21.1 months	+6 weeks
QALY	1.502	1.533	+0.031
Stochastic analysis (mean ± SD)
Cost, £, 2008/2009	£94,687 ± 9099	£92,971 ± 9022	−£1716 ± 1022
Time in pre-FTC state	19.8 months ± 1.6 month	21.1 months ± 1.7 month	+6 weeks ± 2 weeks
QALY	1.503 ± 0.097	1.534 ± 0.095	+0.031 ± 0.013

Figure 2. Cost-effectiveness plane for memantine vs. standard care.

Table 5.  Summary of scenario analyses.

Incremental cost and outcomes	QALYs	Cost*	Time in pre-FTC^†
Base-case analysis
Deterministic analysis	0.031	−1711	0.108
Stochastic analysis	0.031	−1716	0.109
Scenario analyses
Treatment effect – LOCF	0.027	−1587	0.104
Alternative set of utilities (0.34/0.60)	0.028	−1711	0.108
Memantine treatment cost, as per observed treatment duration in the UK (16 months)	0.031	−2211	0.108
Cost pre-FTC –20%	0.031	−1900	0.108
Cost pre-FTC –30%	0.031	−1994	0.108
Cost pre-FTC +20%	0.031	−1522	0.108
Cost pre-FTC +30%	0.031	−1428	0.108
Cost FTC –20%	0.031	−860	0.108
Cost FTC –30%	0.031	−435	0.108
Cost FTC +20%	0.031	−2562	0.108
Cost FTC +30%	0.031	−2987	0.108
Discount rate 0%	0.032	−1890	0.116
Discount rate 6%	0.030	−1595	0.104

*In £2008/09; ^†in years