Characteristics in childhood and adolescence associated with future multiple sclerosis risk in men: cohort study.
OBJECTIVE
Associations with multiple sclerosis (MS) of living conditions in childhood and characteristics in adolescence including physical fitness, cognitive function and psychological stress resilience were investigated.


METHODS
A cohort of male Swedish residents born 1952-1956 who were included in the Swedish Military Conscription Register was used to create a nested case-control study comprising 628 MS cases and 6187 controls matched on birth year, county of residence and vital status at time of diagnosis. Conscription examination records were linked with other national register data. Conditional logistic regression was used to evaluate associations with MS subsequent to the conscription examination.


CONCLUSIONS
Men with MS were less likely to be from more crowded households in childhood (>two persons per room) with an adjusted odds ratio of 0.67 (95% confidence interval 0.51-0.86, P = 0.023). They had lower physical working capacity in adolescence with adjusted odds ratio of 0.94 (95% confidence interval 0.89-0.99, P = 0.026). Cognitive function and stress resilience scores displayed no significant differences between cases and controls. Parental occupation in childhood and body mass index in adolescence were not associated with future MS risk. The inverse association of MS risk with higher levels of household crowding may reflect environmental factors such as the pattern of exposure to microorganisms. Lower physical fitness in men at MS risk may indicate a protective effect of exercise or could be due to prodromal disease activity, although there was no association with cognitive function. Poor psychological stress resilience (and thus risk of chronic stress arousal) was not associated with MS.
Department of Neurology and Neurophysiology, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
M
M
Gunnarsson
Department of Clinical Epidemiology and Biostatistics, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
R
R
Udumyan
Clinical Epidemiology Unit and Centre for Pharmacoepidemiology, Department of Medicine, Karolinska Institutet, Karolinska Hospital, Stockholm, Sweden.|Faculty of Medicine, Golestan University of Medical Sciences, Gorgan, Iran.
S
S
Bahmanyar
Faculty of Medicine and Health, Medicine, Örebro University, Örebro, Sweden.
Y
Y
Nilsagård
Department of Clinical Epidemiology and Biostatistics, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.|Clinical Epidemiology Unit, Department of Medicine, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden.|Research Department of Epidemiology and Public Health, University College, London, UK.
S
S
Montgomery
D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003071:Cognition / Q000502:physiology*; D015331:Cohort Studies; D006801:Humans; D008297:Male; D009103:Multiple Sclerosis / Q000453:epidemiology / Q000209:etiology*; D010809:Physical Fitness / Q000502:physiology*; D012111:Residence Characteristics / Q000706:statistics & numerical data*; D055500:Resilience, Psychological; D012306:Risk; D013315:Stress, Psychological / Q000150:complications / Q000453:epidemiology; D013548:Sweden / Q000453:epidemiology; D055815:Young Adult
cognitive function; cohort; multiple sclerosis; physical fitness; stress