Modelling disease course in amyotrophic lateral Sclerosis: pseudo-longitudinal insights from cross-sectional health-related quality of life data

Health Qual Life Outcomes. 2020 May 1;18(1):117. doi: 10.1186/s12955-020-01372-6.

Abstract

Background: Amyotrophic Lateral Sclerosis (ALS) is a rapidly progressive neurodegenerative disorder with limited robust disease-modifying therapies presently available. While several treatments are aimed at improving health-related quality of life (HRQoL), longitudinal data on how QoL changes across the disease course are rare.

Objectives: To explore longitudinal changes in emotional well-being and HRQoL in ALS.

Methods: Of the 161 subjects initially recruited, 39 received 2 subsequent follow-up assessments at 6 and 12 months after baseline. The ALS Functional Rating Scale-Revised (ALSFRS-R) was used to assess physical impairment. HRQoL was assessed using the ALS Assessment Questionnaire (ALSAQ-40). The D50 disease progression model was applied to explore longitudinal changes in HRQoL.

Results: Patients were primarily in the early semi-stable and early progressive model-derived disease phases. Non-linear correlation analyses showed that the ALSAQ-40 summary index and emotional well-being subdomain behaved differently across disease phases, indicating that the response shift occurs early in disease. Both the ALSFRS-R and ALSAQ-40 significantly declined at 6- and 12-monthly follow-ups.

Conclusion: ALSAQ-40 summary index and emotional well-being change comparably over both actual time and model-derived phases, indicating that the D50 model enables pseudo-longitudinal interpretations of cross-sectional data in ALS.

Keywords: Disease aggressiveness; Health-related quality of life; Longitudinal modelling.

MeSH terms

  • Aged
  • Amyotrophic Lateral Sclerosis / physiopathology*
  • Amyotrophic Lateral Sclerosis / psychology
  • Cross-Sectional Studies
  • Disability Evaluation
  • Disease Progression*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Physical Functional Performance
  • Quality of Life*
  • Surveys and Questionnaires