eCite Digital Repository

Higher latitude is significantly associated with an earlier age of disease onset in multiple sclerosis

Citation

Tao, C and Simpson Jr, S and van der Mei, I and Blizzard, L and Havrdova, E and Horakova, D and Shaygannejad, V and Lugaresi, A and Izquierdo, G and Trojano, M and Duquette, P and Girard, M and Grand'Maison, F and Grammond, P and Alroughani, R and Terzi, M and Oreja-Guevara, C and Sajedi, SA and Iuliano, G and Sola, P and Lechner-Scott, J and Pesch, VV and Pucci, E and Bergamaschi, R and Barnett, M and Ramo, C and Singhal, B and LA Spitaleri, D and Slee, M and Verheul, F and Fernandez Bolanos, R and Amato, MP and Cristiano, E and Granella, F and Hodgkinson, S and Fiol, M and Gray, O and McCombe, P and Saladino, ML and Sanchez Menoyo, JL and Shuey, N and Vucic, S and Shaw, C and Deri, N and Arruda, WO and Butzkueven, H and Spelman, T and Taylor, BV, on behalf of the MSBase Study Group, Higher latitude is significantly associated with an earlier age of disease onset in multiple sclerosis, Journal of Neurology, Neurosurgery and Psychiatry, 87, (12) pp. 1343-1349. ISSN 0022-3050 (2016) [Refereed Article]

Copyright Statement

Copyright 2016 the authors.

DOI: doi:10.1136/jnnp-2016-314013

Abstract

BACKGROUND: Age at onset (AAO) in multiple sclerosis (MS) is an important marker of disease severity and may have prognostic significance. Understanding what factors can influence AAO may shed light on the aetiology of this complex disease, and have applications in the diagnostic process.

METHODS: The study cohort of 22 162 eligible patients from 21 countries was extracted from the MSBase registry. Only patients with MS aged ≥16 years were included. To reduce heterogeneity, only centres of largely European descent were included for analysis. AAO was defined as the year of the first symptom suggestive of inflammatory central nervous system demyelination. Predictors of AAO were evaluated by linear regression.

RESULTS: Compared with those living in lower latitudes (19.0-39.9°), onset of symptoms was 1.9 years earlier for those at higher latitudes (50.0-56.0°) (p=3.83×10-23). A reciprocal relationship was seen for ambient ultraviolet radiation (UVR), with a significantly increasing AAO for patients with MS per each quartile increment of ambient UVR (p=1.56×10-17). We found that the AAO of female patients was ∼5 months earlier than male patients (p=0.002). AAO of progressive-onset patients with MS were ∼9 years later than relapsing-onset patients (p=1.40×10-265).

CONCLUSIONS: An earlier AAO in higher latitude regions was found in this worldwide European-descent cohort and correlated inversely with variation in latitudinal UVR. These results suggest that environmental factors which act at the population level may significantly influence disease severity characteristics in genetically susceptible populations.

Item Details

Item Type:Refereed Article
Research Division:Biomedical and Clinical Sciences
Research Group:Neurosciences
Research Field:Central nervous system
Objective Division:Health
Objective Group:Clinical health
Objective Field:Clinical health not elsewhere classified
UTAS Author:Tao, C (Mr Chunrong Tao)
UTAS Author:Simpson Jr, S (Dr Steve Simpson JR)
UTAS Author:van der Mei, I (Professor Ingrid van der Mei)
UTAS Author: