Clinical features and incidence trends of amyotrophic lateral sclerosis in Navarre, Spain, 2007–2018: a population-based study

Abstract

Objective: Amyotrophic Lateral Sclerosis (ALS) is a heterogeneous neurodegenerative disorder with a median survival of 3 years. The aim of our study is to analyze the incidence, age-related phenotype and clinical onset, geographical distribution, survival and diagnostic delay of ALS in Navarre. Methods: This is a population-based observational retrospective study, including all residents of Navarre (a northern Spanish region) from 2007 to 2018, who were followed until 30th September 2020. Results: We observed a global incidence 2.47/100,000 person-years, with an upward trend throughout the study, with the highest being in the age group of 70–74 years old. Point prevalence in December 2018 was 6.64/100,000 inhabitants (95%CI: 4.52–8.45). Upper limbs weakness onset was the most frequent in young people (<60 years), and bulbar, lower limbs weakness, generalized and respiratory associated with older age. Bulbar phenotype is the most frequent in women and in 80+ group. The median survival from clinical onset was 27.7 months (95%CI: 24.0–31.4), higher in spinal phenotype and younger onset age, and the diagnosis delay was 10.0 months (95%CI: 8.9–11.2) from clinical onset. Conclusions: We have observed a trend of increasing incidence in older people where the bulbar phenotype and female predominance

Keywords:

• Amyotrophic Lateral Sclerosis
• epidemiology
• incidence
• diagnosis delay
• survival

Acknowledgements

The authors thank all those responsible of the case ascertainment sources consulted for their collaboration and to Eva Ardanaz for their kind advices.

Ethics approval and consent to participate

The study protocol was approved by the Navarre Ethical Committee for Medical Research (Pyto 2016/31).

Declaration of interest

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study was partially supported by the Health Department of Navarre Government [project 007–2017], co-funded (50%) by the European Regional Development Fund (ERFD) through the Navarre ERDF 2014–2020 Operative Programme.