Table 1.
Characteristics of included studies
|
Author (year) Country |
MS (n) |
Control group (n) |
F : M cases |
Mean age at MS onset (years) |
LAT |
NOS Score |
MS Dx criterion |
Timing of surgery |
Confounder variables |
Exposure 1: Tonsil OR1 |
Exposure 2: Append OR1 |
Exposure 3: Adenoid OR1 |
Exposure 4: Other OR1 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| (95% CI) | (95% CI) | (95% CI) | (95% CI) | ||||||||||
|
Alonso (2011) Iran |
394 |
394 |
3.70 |
24.9 |
32 |
6 |
M |
Pre |
Age, sex |
0.92 (0.51-1.64) |
1.07 (0.52-2.19) |
-- |
-- |
|
Alter (1968) USA |
36 |
72 |
|
|
45 |
4 |
N |
Pre |
Age, sex, age at onset |
-- |
-- |
-- |
0.78 (0.33-1.81) |
|
Anderson (1981) Denmark |
92 |
276 |
1.42 |
42.4 |
56 |
8 |
A; after 1994, Mc |
≤ 20 y |
Age, sex, month of birth, years in school |
0.73 (0.32-1.64) |
0.81 (0.22-2.98) |
1.08 (0.64-1.82) |
-- |
|
Antonovsky (1965) Israel |
241 |
964 |
1.10 |
|
31 |
5 |
N |
≤ 15 y, > 15 y |
Age, sex, age of onset, region of birth |
-- |
-- |
-- |
NS2 |
|
Bansil (1997) India |
56 |
147 |
1.67 |
28 |
24 |
3 |
P |
Pre |
Birth place, religion, residence |
-- |
-- |
-- |
0.97 (0.49-1.91) |
|
Berr (1989) France |
63 |
63 |
2.70 |
30.8 |
42 |
5 |
P |
Pre |
Age, sex, residence |
1.0 (0.38-2.60) |
-- |
-- |
-- |
|
Bobowick (1978) USA |
10 |
8 |
|
29.7 |
40 |
6 |
N |
≤ 20 y |
Age, sex |
2.50 (0.37-16.89) |
5.0 (0.21-120.4) |
-- |
-- |
|
Broadley (2000) England |
595 |
372 |
3.16 |
28 |
52 |
1 |
N |
Pre |
None stated |
1.02 (0.77-1.34) |
-- |
-- |
-- |
|
Casetta (1994) Italy |
104 |
150 |
2.0 |
32.2 |
44 |
5 |
Mc |
≤ 15 y, > 15 y |
Age (> 3 y), sex, residence |
1.04 (0.62-1.76) |
-- |
-- |
-- |
|
Cendrowski (1969) Poland |
300 |
300 |
|
31.9 |
52 |
3 |
N |
≤ 15 y |
None stated |
0.74 (0.43-1.27) |
-- |
-- |
-- |
|
Currier (1982) Canada & USA |
40 |
40 |
1.0 |
30 |
49 |
5 |
A |
Pre |
Age, sex |
-- |
-- |
-- |
2.22 (0.86-5.74) |
|
Currier (1974) Ireland |
60 |
60 |
1.4 |
26 |
53 |
3 |
A |
≤ 20 y |
Age, sex, social class, marital status |
1.18 (0.53-2.61) |
1.46 (0.54-3.93) |
-- |
1.45 (0.62-3.41) |
|
de Gennaro (2009) Italy & Serbia |
104 |
150 |
2.06 |
28 |
44 |
3 |
M |
≤ 15 y, > 15 y |
Age, sex, residence |
≤ 15 y: 2.50 |
< 15 y: 1.60 |
-- |
-- |
| (1.42-4.41)* |
(0.91-2.79) |
||||||||||||
| > 15 y: |
> 15 y: |
||||||||||||
| 2.20 (1.30-3.73)* |
1.92 (1.09-3.41)* |
||||||||||||
|
da Silva (2009) Brazil |
81 |
81 |
2.10 |
|
22 |
4 |
N |
Pre |
Age, sex, place of birth |
-- |
-- |
-- |
1.82 (0.95-3.51) |
|
Dolan (2003) USA |
24 |
24 |
2.0 |
35.4 |
42 |
3 |
P |
≤ 20 y |
Age, sex |
-- |
-- |
-- |
2.14 (0.63-7.33) |
|
Dokuchaeva (2006) Russia |
178 |
178 |
2.80 |
|
48 |
|
No data |
≤ 15 y, > 15 y |
Age, sex, ethnic origin |
≤ 15 y: 1.61 (1.01-2.56) |
-- |
-- |
-- |
| > 15 y: | |||||||||||||
| 1.0 (0.64-1.56) | |||||||||||||
|
Gronning (1993) Norway |
155 |
200 |
1.50 |
-- |
60 |
4 |
B |
≤20 y |
Age, sex, residence |
1.90 (1.15-3.16)* |
1.10 (0.53-2.28) |
-- |
-- |
|
Gusev (1996) Russia |
155 |
155 |
1.63 |
25.8 |
56 |
3 |
Mc |
≤ 15 y, > 15 y |
Age, sex, residence, and ethnicity |
0.85 (0.38-1.89) |
-- |
-- |
-- |
|
Hopkins (1991) USA |
14 |
56 |
4.30 |
35.2 |
41 |
7 |
P |
Pre |
Age, sex, race |
-- |
-- |
-- |
NS2 |
|
Koch (1974) USA |
7 |
7 |
2.50 |
29.3 |
46 |
4 |
N |
Pre |
None stated |
-- |
-- |
-- |
1.0 (0.12-8.31) |
|
Koch-Henriksen (1989) Denmark |
297 |
297 |
1.42 |
32 |
56 |
8 |
A |
≤ 15 y, > 15 y |
Age, sex |
≤ 15 y: |
≤ 15 y: |
≤ 15 y: |
-- |
| 0.89 (0.52-1.53) |
2.19 (0.93-5.16) |
0.85 (0.54-1.34) |
|||||||||||
| > 15 y: |
> 15 y: |
||||||||||||
| 1.49 (0.72-3.08) |
1.24 (0.70-2.21) |
||||||||||||
|
Kurtzke (1997) Norway |
23 |
127 |
1.55 |
30 |
62 |
5 |
Schumacher committee |
Pre |
Age, sex |
-- |
-- |
-- |
1.19 (0.48-2.95) |
|
Lamoureux (1976) Canada |
23 |
23 |
1.09 |
|
|
5 |
N |
Pre |
Age, sex, place of origin |
3.56 (1.05-12.05) |
3.05 (0.78-11.96) |
-- |
-- |
|
Lauer (1994) Germany |
150 |
150 |
2.04 |
30.3 |
51 |
4 |
B |
≤ 14 y |
Age, sex, type of residence |
-- |
NS2 |
-- |
0.53 (0.32-0.86)* |
|
Martinez-Sobrepera (2001) Cuba |
50 |
50 |
4.50 |
-- |
21 |
5 |
P |
Pre |
Age, gender, skin color |
-- |
-- |
-- |
1.50 (0.68-3.29) |
|
Poskanzer (1980) USA |
77 |
77 |
2.04 |
31 |
42 |
4 |
N |
Pre |
None stated |
NS2 |
-- |
-- |
NS2 |
|
Poskanzer (1965) Scotland |
210 |
210 |
1.31 |
33.6 |
60 |
8 |
A |
≤ 20 y |
Age, sex, residence |
1.69 (1.15-2.50)* |
1.42 (0.86-2.35) |
-- |
-- |
|
Roshanisefat (2011) Sweden |
20,542 |
204,157 |
1.87 |
46.3 |
-- |
6 |
MS register |
≤ 20 y, > 20 y |
Age, sex, age at onset, region |
-- |
≤ 20 y: |
-- |
-- |
| 1.11 (0.94-1.31) | |||||||||||||
| > 20 y: | |||||||||||||
| 1.02 (0.93-1.11) | |||||||||||||
|
Westlund (1953) Canada |
112 |
123 |
1.43 |
30.3 |
49 |
5 |
N |
Pre |
Age, sex, age at onset |
-- |
-- |
-- |
2.26 (1.24-4.15)* |
|
YosefiPour (2002) Iran |
149 |
100 |
1.19 |
-- |
32 |
4 |
N |
Pre |
Age, sex |
-- |
-- |
-- |
3.93 (1.97-7.84)* |
|
Zaadstra (2008) Netherlands |
2,821 |
2,550 |
2.30 |
-- |
52 |
7 |
N |
< 25 y |
Age, sex, education, residence |
1.25 (1.11-1.40)* |
-- |
-- |
-- |
|
Zilber (1996) Israel |
70 |
64 |
1.73 |
25.2 |
31 |
6 |
M |
≤ 20 y, Pre |
Age, sex |
≤ 20 y: |
-- |
< 10 y: 3.0 (0.77-11.62) |
0.58 (0.29-1.17) |
| 1.06 (0.47-2.39) | |||||||||||||
| Pre: 0.96 (0.44-2.11) | |||||||||||||
| Zorzon (2003) Italy | 140 | 131 | 1.72 | 31.2 | 45 | 5 | M | Pre | None stated | -- | -- | -- | 0.46 (0.28-0.76)* |
1 Odds ratio for combined surgeries using a random effects model.
2 Reported as not statistically significant, no data provided.
* Indicates statistically significant results.
A = Allison & Miller criteria, Append = appendectomy, Adenoid = adenoidectomy, B = Bauer criteria, CI = confidence interval, Dx = diagnosis, LAT = latitude, Mc = McAlpine criteria, M = McDonald criteria, MS = multiple sclerosis, NOS = Newcastle-Ottawa Scale, N = neurologist diagnosed, NS = not significant, OR = odds ratio, P = Poser criteria, Pre: Premorbid, age not specified other than surgery occurring before MS diagnosis, Tonsil = tonsillectomy, Y = years.