PMID- 22998435
OWN - NLM
STAT- MEDLINE
DCOM- 20130131
LR  - 20220311
IS  - 1471-2377 (Electronic)
IS  - 1471-2377 (Linking)
VI  - 12
DP  - 2012 Sep 24
TI  - Geomagnetic disturbances may be environmental risk factor for multiple sclerosis: 
      an ecological study of 111 locations in 24 countries.
PG  - 100
LID - 10.1186/1471-2377-12-100 [doi]
AB  - BACKGROUND: We noticed that a hypothesis based on the effect of geomagnetic 
      disturbances (GMD) has the ability to explain special features of multiple 
      sclerosis (MS). Areas around geomagnetic 60 degree latitude (GM60L) experience 
      the greatest amount of GMD. The easiest way to evaluate our hypothesis was to 
      test the association of MS prevalence (MSP) with angular distance to geomagnetic 
      60 degree latitude (AMAG60) and compare it with the known association of MS with 
      geographical latitude (GL). We did the same with angular distance to geographic 
      60 degree latitude (AGRAPH60) as a control. METHODS: English written papers with 
      MSP keywords, done in Europe (EUR), North America (NA) or Australasia (AUS) were 
      retrieved from the PubMed. Geomagnetic coordinates were determined for each 
      location and AMAG60 was calculated as absolute value of numerical difference 
      between its geomagnetic latitude from GM60L. By an ecological study with using 
      meta-regression analyses, the relationship of MSP with GL, AMAG60 and AGRAPH60 
      were evaluated separately. MSP data were weighted by square root of number of 
      prevalent cases. Models were compared by their adjusted R square (AR2) and 
      standard error of estimate (SEE). RESULTS: 111 MSP data were entered in the 
      study. In each continent, AMAG60 had the best correlation with MSP, the largest 
      AR2 (0.47, 0.42 and 0.84 for EUR, NA and AUS, respectively) and the least SEE. 
      Merging both hemispheres data, AMAG60 explained 56% of MSP variations with the 
      least SEE (R = 0.75, AR2 = 0.56, SEE = 57), while GL explained 17% (R = 0.41, AR2 
      = 0.17, SEE = 78.5) and AGRAPH60 explained 12% of that variations with the 
      highest SEE (R = 0.35, AR2 = 0.12, SEE = 80.5). CONCLUSIONS: Our results 
      confirmed that AMAG60 is the best describer of MSP variations and has the 
      strongest association with MSP distribution. They clarified that the well-known 
      latitudinal gradient of MSP may be actually a gradient related to GM60L. 
      Moreover, the location of GM60L can elucidate why MSP has parabolic and linear 
      gradient in the north and south hemisphere, respectively. This preliminary 
      evaluation supported that GMD can be the mysterious environmental risk factor for 
      MS. We believe that this hypothesis deserves to be considered for further 
      validation studies.
FAU - Sajedi, Seyed Aidin
AU  - Sajedi SA
AD  - Neurology Department, Golestan Hospital, Ahvaz Jundishapur University of Medical 
      Sciences, Ahvaz, Iran. dr.sajedy@gmail.com
FAU - Abdollahi, Fahimeh
AU  - Abdollahi F
LA  - eng
PT  - Journal Article
DEP - 20120924
PL  - England
TA  - BMC Neurol
JT  - BMC neurology
JID - 100968555
SB  - IM
MH  - *Causality
MH  - *Ecosystem
MH  - *Electromagnetic Fields
MH  - Environmental Exposure/*statistics & numerical data
MH  - Geography, Medical
MH  - Humans
MH  - Male
MH  - Multiple Sclerosis/*epidemiology
MH  - *Solar Activity
PMC - PMC3488506
EDAT- 2012/09/25 06:00
MHDA- 2013/02/01 06:00
PMCR- 2012/09/24
CRDT- 2012/09/25 06:00
PHST- 2012/06/03 00:00 [received]
PHST- 2012/09/04 00:00 [accepted]
PHST- 2012/09/25 06:00 [entrez]
PHST- 2012/09/25 06:00 [pubmed]
PHST- 2013/02/01 06:00 [medline]
PHST- 2012/09/24 00:00 [pmc-release]
AID - 1471-2377-12-100 [pii]
AID - 10.1186/1471-2377-12-100 [doi]
PST - epublish
SO  - BMC Neurol. 2012 Sep 24;12:100. doi: 10.1186/1471-2377-12-100.