Confirmation of early non-bulbar onset of amyotrophic lateral sclerosis in Spanish league soccer players.
Level 4 - case-series / case-control
Case series of 7 patients without a control group
PubMed 34343861 · doi:10.1016/j.jns.2021.117586
What was done
The authors characterized the clinical phenotype of 7 retired Spanish professional and semi-professional soccer players diagnosed with amyotrophic lateral sclerosis (ALS) between 2000 and 2020. Cases were identified retrospectively from personal archives of an ALS unit, literature and website searches, and media self-reports. Data collected included age and site of symptom onset, survival, history of trauma, playing position, and latency from retirement to symptom onset.
What was found
Among the 7 identified cases: - Mean age at onset was 41.5 years (SD 9.2, median 45.5, range 31.5-51.2). - Site of onset was spinal in 6 patients (including 3 with the flail arm syndrome variant) and bulbar in 1 individual. - Playing positions were goalkeepers (n=2), defenders (n=2), and midfielders (n=3). - Four patients had a history of trauma (two serious). - Mean time between retirement and first symptoms was 9.4 years (SD 8.0, median 15.2, range 0.1-17.5). - Survival time for the two deceased patients was 71.8 months.
Why it matters
This report describes an early onset of ALS among Spanish soccer players, corroborating previous Italian findings while noting a predominance of spinal and upper limb onset rather than bulbar onset.
Limits
The sample size is very small (n=7) and lacks a control or reference cohort to assess true incidence or causation. Case ascertainment relied partly on media self-reports and online searches, introducing substantial selection and reporting bias. Underlying genetic factors and exact athletic exposure metrics were not detailed.
Cited by
- supports Three epidemiological studies (in Italy, Spain, and Scotland) have linked professional soccer playing to an increased risk of ALS.