Related Experiment Videos
Does delay in acquiring childhood infection increase risk of multiple sclerosis?
Abstract:
Multiple sclerosis (MS) appears to be more common in technically advanced countries than in underdeveloped regions and migration from one area to another at a young age affects the risk of acquiring MS. One way of explaining both the peculiar frequency distribution and the effect of migration while young is to postulate that an infection early in life decreases the chance of central demyelination. However, no specific infection has been implicated consistently. Alternatively, an aberrant host response to infection in childhood might induce central demyelination. Thus, the aberrant host response could be age-dependent. In seeking associations between age of infection and risk of MS, we observed a direct relationship: where childhood diseases were acquired early in life, the frequency of MS in that population was low; where childhood diseases tended to occur nearer adolescence, MS frequency in that population was high. Since immune responsiveness to antigenic challenges matures through early adolescence, we reason that early infection might be protective and delay in acquiring childhood infections might increase the risk of developing MS. Indeed, in experimental models, the chance of inducing chronic relapsing central demyelination is increased by using adolescent rather than newborn or mature animals. In this paper, epidemiologic evidence showing the strong association between age of infection and risk of MS is presented.
Insights
Early childhood infections may protect against multiple sclerosis (MS). Delaying common childhood diseases until adolescence appears to increase the risk of developing MS later in life.
Area of Science:
- Epidemiology
- Immunology
- Neurology
Background:
- Multiple sclerosis (MS) prevalence varies globally, higher in developed nations.
- Migration patterns and early-life exposures influence MS risk.
- The role of infections in MS etiology remains unclear, with hypotheses suggesting both protective and causative mechanisms.
Purpose of the Study:
- To investigate the association between the age of acquiring childhood infections and the risk of developing multiple sclerosis.
- To explore the hypothesis that early-life infections may confer protection against central demyelination.
Main Methods:
- Epidemiological analysis of population data correlating childhood disease timing with MS frequency.
- Review of experimental models investigating the impact of age on susceptibility to demyelination.
Main Results:
- A direct relationship was observed: populations with early childhood disease acquisition showed lower MS frequency.
- Populations where childhood diseases occurred later (near adolescence) exhibited higher MS frequency.
- Experimental models indicated increased susceptibility to demyelination in adolescent animals compared to newborns or mature ones.
Conclusions:
- Acquiring common childhood infections early in life may be protective against developing multiple sclerosis.
- Delayed acquisition of childhood infections, closer to adolescence, is associated with an increased risk of MS.
- Immune system maturation may play a critical role in the age-dependent protective or risk-modifying effects of infections on MS development.