Spatial epidemiology of amyotrophic lateral sclerosis in Piedmont and Aosta Valley, Italy: a population‐based cluster analysis. (25th March 2018)

• Record Type: Journal Article
• Authors: Vasta, R.; Calvo, A.; Moglia, C.; Cammarosano, S.; Manera, U.; Canosa, A.; D'Ovidio, F.; Mazzini, L.; Chiò, A.
• Is Part Of: European journal of neurology. Volume 25:Number 6(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-03-25
• Subjects: amyotrophic lateral sclerosis -- motor neuron diseases -- spatial epidemiology; Neurology -- Periodicals; Nervous system -- Diseases -- Periodicals; 616.8
• DOI: 10.1111/ene.13586
• Languages: English
• ISSNs: 1351-5101

Abstract

Abstract : Background and purpose: The analysis of the spatial distribution of cases could give important cues on putative environmental causes of a disease. Our aim was to perform a spatial analysis of an amyotrophic lateral sclerosis (ALS) cohort from the Piedmont and Aosta Valley ALS register (PARALS) over a 20‐year period. Methods: The address at the moment of diagnosis was considered for each ALS case. Municipalities' and census divisions' resident populations during the 1995–2014 period were obtained. A cluster analysis was performed adopting both Moran's index and the Kulldorff spatial scan statistic. Results: A total of 2702 ALS patients were identified. An address was retrieved for 2671 (99%) patients. Moran's index was −0.01 ( P value 0.83), thus revealing no clusters. SaTScan identified no statistically significant clusters. When census divisions were considered, Moran's index was 0.13 ( P value 0.45); SaTScan revealed one statistically significant small cluster in the province of Alessandria. Here, 0.0099 cases were expected and three cases were observed (relative risk 304.60; 95% confidence interval 109.83–845.88, P value 0.03). Discussion: Our study showed a substantial homogeneous distribution of ALS cases in Piedmont and Aosta Valley. The population‐based setting and the adoption of proper statistical analyses strengthen the validity of our results. Such a finding further suggests the involvement of multiple environmental and genetic factors in ALS pathogenesis.