Download Descriptive Epidemiology of MS

Descriptive
Epidemiology of
Multiple Sclerosis
(MS)
Course of Disease
Acute - Very Rapid Course, Death in a
few months
Progressive - Gradually becoming
worse, well defined remissions and
exacerbations
Benign - Exacerbations with very long
remissions
Subclinical - No Symptoms, identified
at autopsy
Acute
Progressive
Epidemiology:
Incidence of MS in Denmark
10
8
6
Males
Females
4
2
0
10
20
30
40
50
60
Incidence of MS in Iceland
3.5
per/100,000
3
2.5
2
1.5
1
0.5
0
1900 1910 1920 1930 1940 1950 1960 1970
Incidence of MS in Faroe Islands
12
10
8
Native
Post-war birth
6
4
2
1980
1975
1970
1965
1960
1955
1950
1945
1940
1935
0
Incidence of MS
in Faroe Islands by age
10
to
14
15
-19
20
-24
25
-29
30
-34
35
-39
40
-44
45
-49
6
5
4
3
2
1
0
Females
Males
16
13
10
to
to
to
9
6
3
18
15
12
7t
o
4t
o
1t
o
per 100,000
Years since 1942:
in Faroe Islands
8
6
4
2
0
Incidence of MS
in South Africa
12
Immigrants
10
SA Born African
Speak
SA Born English
Speak
All White SA
8
6
4
2
0
10
20
30
40
50
Prevalence of MS
140
120
100
Winnipeg
Boston
New Orleans
80
60
40
20
0
0
10
20
30
40
50
60
70
80
Unusual Occurrence of MS in
Tropical Island
6
5
4
3
2
84
82
80
78
76
74
72
70
68
66
64
62
0
60
1
Risk Factors:
Unusual Stress in 2 Yrs Before
Cases
79%
Controls
54%
p value
<0.01
Risk factors:
Exposed to Animal Illness
Cases
Controls
43%
19%
Risk Factors:
Exposed to Canine Distemper
Cases
Control
17%
6%
Physical Activity and MS
Physically
Active
Mixed
Activities
Sedentary
Hobbies
None
Cases
50%
Controls
34%
27%
24%
20%
36%
3%
6%
Immunologic Involvement
Autoantibodies
Encephalomyelitis developing-Similar to the administration of
rabies virus vaccine
 Evidence for a superantigen?
Frequency of Viral Infection
Colds
Flu
Enteric Herpes
Controls
9%
9%
0%
Cases
5%
2%
8% .03%
3%
Concordance Rates in Twins
MZ
DZ
31/107
13/101
0.29
0.13
Prevalence of MS in First
Degree Relatives
Sibs
Parents Offspring
125/10,682
41/6,521
9/1,521
0.0117
0.0063
0.0059
DZ Risk versus Sibling Risk
DZ
Sibling
0.13
0.012
HLA Antigens and MS:
Northern Europeans
Cases
Controls RR
A3
32
21
1.8
B7
35
18
2.5
DR2
41
22
2.5
Conclusions
MS caused by environmental
factors, but not clear what they
are
For MS there is evidence for
HLA associations, however,
there is more than HLA
MS is a multiloci disease