Impact of early intervention and disease modification in patients with predementia Alzheimer’s disease: a Markov model simulation

Figures & data

Figure 1 Model flow. Transition probabilities: P₀, probability of remaining in current state; P₁, probability of transitioning to next, more severe state; P_D, probability of death.

Abbreviation: AD, Alzheimer’s disease.

Table 1 Definition of disease states for Alzheimer’s disease

Disease state	MMSE range
Predementia	26–30
Mild AD	21–25
Moderate AD	10–20
Severe AD	<10

Abbreviations: AD, Alzheimer’s disease; MMSE, Mini Mental State Examination.

Figure 2 Intradisease state outcome details. Transition probabilities: P₀, probability of remaining in current state; P₁, probability of transitioning to next, more severe state; P_D, probability of death.

Abbreviation: LTC, long-term care.

Figure 3 Left panel: Markov model results showing the estimated count of patients (y axis) and time spent (x axis) with predementia or mild AD when initiating DMT during predementia AD (light gray line), DMT during mild–moderate AD (medium gray line), or SOC during mild–moderate AD (black line). Right panel: the cumulative time spent in predementia or mild AD if initiating DMT during predementia AD (light gray line), DMT during mild–moderate AD (medium gray line), or SOC during predementia AD (black line).

Abbreviations: AD, Alzheimer’s disease; DMT, disease-modifying therapy; SOC, standard of care.

Figure 4 Left panel: Markov model results showing the estimated count of patients (y axis) and time spent (x axis) with moderate–severe AD when initiating DMT during predementia AD (light gray line), DMT during mild–moderate AD (medium gray line), or SOC during mild–moderate AD (black line). Right panel: the cumulative time spent in moderate or severe AD if initiating DMT during predementia AD (light gray line), DMT during mild–moderate AD (medium gray line), or SOC during predementia AD (black line).

Abbreviations: AD, Alzheimer’s disease; DMT, disease-modifying therapy; SOC, standard of care.

Figure 5 Estimated patient count (y axis) and time of death (x axis) for patients initiating DMT during predementia AD (light gray line), DMT during mild–moderate AD (medium gray line), or SOC during mild–moderate AD (black line).

Abbreviations: AD, Alzheimer’s disease; DMT, disease-modifying therapy; SOC, standard of care.

Table 2 Average life-years in disease states for different DMT efficacies (all data in years)

DMT relative advantage	DMT during predementia		DMT during moderate AD		SOC during moderate AD
	Mild	Severe	Mild	Severe	Mild	Severe
10%	3.46	2.54	3.35	2.60	3.19	2.56
20%	3.78	2.40	3.54	2.53	3.19	2.56
25%	3.96	2.32	3.65	2.49	3.19	2.56

Abbreviations: AD, Alzheimer’s disease; DMT, disease-modifying therapy; SOC, standard of care.

Figure 6 Estimated patient count (y axis) and time spent (x axis) in the community if initiating DMT during predementia AD (light gray line), DMT during mild–moderate AD (medium gray line), or SOC during mild–moderate AD (black line). Right panel: the cumulative time spent in the community if initiating DMT during predementia AD (light gray line), DMT during mild–moderate AD (medium gray line), or SOC during mild–moderate AD (black line).

Abbreviations: AD, Alzheimer’s disease; DMT, disease-modifying therapy; SOC, standard of care.

Figure 7 Estimated count of patients (y axis) and time spent (x axis) in long-term care if initiating DMT during predementia AD (light gray line), mild–moderate AD (medium gray line), or SOC during predementia AD (black line). Right panel: the cumulative time spent in long-term care if initiating DMT during predementia (light gray line), DMT during mild–moderate AD (medium gray line), or SOC during mild–moderate AD (black line).

Abbreviations: AD, Alzheimer’s disease; DMT, disease-modifying therapy; SOC, standard of care.

Table 3 Life-years in the community (home) versus in long-term care for different DMT efficacies (all data in years)

DMT relative advantage	DMT during predementia		DMT during moderate AD		SOC during moderate AD
	Home	LTC	Home	LTC	Home	LTC
10%	4.87	1.13	4.79	1.16	4.44	1.30
20%	5.16	1.02	4.99	1.08	4.44	1.30
25%	5.37	0.90	5.10	1.04	4.44	1.30

Abbreviations: AD, Alzheimer’s disease; DMT, disease-modifying therapy; LTC, long-term care; SOC, standard of care.