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Progression analysis versus traditional methods to quantify slowing of disease progression in Alzheimer’s disease

Jönsson, Linus ; Ivkovic, Milana ; Atri, Alireza ; Handels, Ron ; Gustavsson, Anders ; Hahn-Pedersen, Julie Hviid ; León, Teresa ; Lilja, Mathias ; Gundgaard, Jens and Raket, Lars Lau LU orcid (2024) In Alzheimer's Research and Therapy 16(1).
Abstract

Background: The clinical meaningfulness of the effects of recently approved disease-modifying treatments (DMT) in Alzheimer’s disease is under debate. Available evidence is limited to short-term effects on clinical rating scales which may be difficult to interpret and have limited intrinsic meaning to patients. The main value of DMTs accrues over the long term as they are expected to cause a delay or slowing of disease progression. While awaiting such evidence, the translation of short-term effects to time delays or slowing of progression could offer a powerful and readily interpretable representation of clinical outcomes. Methods: We simulated disease progression trajectories representing two arms, active and placebo, of a hypothetical... (More)

Background: The clinical meaningfulness of the effects of recently approved disease-modifying treatments (DMT) in Alzheimer’s disease is under debate. Available evidence is limited to short-term effects on clinical rating scales which may be difficult to interpret and have limited intrinsic meaning to patients. The main value of DMTs accrues over the long term as they are expected to cause a delay or slowing of disease progression. While awaiting such evidence, the translation of short-term effects to time delays or slowing of progression could offer a powerful and readily interpretable representation of clinical outcomes. Methods: We simulated disease progression trajectories representing two arms, active and placebo, of a hypothetical clinical trial of a DMT. The placebo arm was simulated based on estimated mean trajectories of clinical dementia rating scale–sum of boxes (CDR-SB) recordings from amyloid-positive subjects with mild cognitive impairment (MCI) from Alzheimer’s Disease Neuroimaging Initiative (ADNI). The active arm was simulated to show an average slowing of disease progression versus placebo of 20% at each visit. The treatment effects in the simulated trials were estimated with a progression model for repeated measures (PMRM) and a mixed model for repeated measures (MMRM) for comparison. For PMRM, the treatment effect is expressed in units of time (e.g., days) and for MMRM in units of the outcome (e.g., CDR-SB points). PMRM results were implemented in a health economics Markov model extrapolating disease progression and death over 15 years. Results: The PMRM model estimated a 19% delay in disease progression at 18 months and 20% (~ 7 months delay) at 36 months, while the MMRM model estimated a 25% reduction in CDR-SB (~ 0.5 points) at 36 months. The PMRM model had slightly greater power compared to MMRM. The health economic model based on the estimated time delay suggested an increase in life expectancy (10 months) without extending time in severe stages of disease. Conclusion: PMRM methods can be used to estimate treatment effects in terms of slowing of progression which translates to time metrics that can be readily interpreted and appreciated as meaningful outcomes for patients, care partners, and health care practitioners.

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author
; ; ; ; ; ; ; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Alzheimer’s disease, Disease progression, Statistical model
in
Alzheimer's Research and Therapy
volume
16
issue
1
article number
48
publisher
BioMed Central (BMC)
external identifiers
  • pmid:38424559
  • scopus:85186342375
ISSN
1758-9193
DOI
10.1186/s13195-024-01413-y
language
English
LU publication?
yes
id
7dffd993-6be0-4ed2-8630-ea5f7908015e
date added to LUP
2024-03-14 11:02:17
date last changed
2024-04-25 07:39:39
@article{7dffd993-6be0-4ed2-8630-ea5f7908015e,
  abstract     = {{<p>Background: The clinical meaningfulness of the effects of recently approved disease-modifying treatments (DMT) in Alzheimer’s disease is under debate. Available evidence is limited to short-term effects on clinical rating scales which may be difficult to interpret and have limited intrinsic meaning to patients. The main value of DMTs accrues over the long term as they are expected to cause a delay or slowing of disease progression. While awaiting such evidence, the translation of short-term effects to time delays or slowing of progression could offer a powerful and readily interpretable representation of clinical outcomes. Methods: We simulated disease progression trajectories representing two arms, active and placebo, of a hypothetical clinical trial of a DMT. The placebo arm was simulated based on estimated mean trajectories of clinical dementia rating scale–sum of boxes (CDR-SB) recordings from amyloid-positive subjects with mild cognitive impairment (MCI) from Alzheimer’s Disease Neuroimaging Initiative (ADNI). The active arm was simulated to show an average slowing of disease progression versus placebo of 20% at each visit. The treatment effects in the simulated trials were estimated with a progression model for repeated measures (PMRM) and a mixed model for repeated measures (MMRM) for comparison. For PMRM, the treatment effect is expressed in units of time (e.g., days) and for MMRM in units of the outcome (e.g., CDR-SB points). PMRM results were implemented in a health economics Markov model extrapolating disease progression and death over 15 years. Results: The PMRM model estimated a 19% delay in disease progression at 18 months and 20% (~ 7 months delay) at 36 months, while the MMRM model estimated a 25% reduction in CDR-SB (~ 0.5 points) at 36 months. The PMRM model had slightly greater power compared to MMRM. The health economic model based on the estimated time delay suggested an increase in life expectancy (10 months) without extending time in severe stages of disease. Conclusion: PMRM methods can be used to estimate treatment effects in terms of slowing of progression which translates to time metrics that can be readily interpreted and appreciated as meaningful outcomes for patients, care partners, and health care practitioners.</p>}},
  author       = {{Jönsson, Linus and Ivkovic, Milana and Atri, Alireza and Handels, Ron and Gustavsson, Anders and Hahn-Pedersen, Julie Hviid and León, Teresa and Lilja, Mathias and Gundgaard, Jens and Raket, Lars Lau}},
  issn         = {{1758-9193}},
  keywords     = {{Alzheimer’s disease; Disease progression; Statistical model}},
  language     = {{eng}},
  number       = {{1}},
  publisher    = {{BioMed Central (BMC)}},
  series       = {{Alzheimer's Research and Therapy}},
  title        = {{Progression analysis versus traditional methods to quantify slowing of disease progression in Alzheimer’s disease}},
  url          = {{http://dx.doi.org/10.1186/s13195-024-01413-y}},
  doi          = {{10.1186/s13195-024-01413-y}},
  volume       = {{16}},
  year         = {{2024}},
}