1, Kotzamani

Table e-1. Age and gender distribution of MS patients

Age, y Females, n(%) Males, n (%) F:M Total, n(%) <25 22 (5.4) 14 (5.6) 1.6 36 (5.5) 25-29 32 (7.9) 20 (8) 1.6 52 (7.9) 30-34 58 (14.3) 35 (14) 1.7 93 (14.2) 35-39 62 (15.3) 32 (12.8) 1.9 94 (14.4 40-44 60 (14.8) 32 (12.8) 1.9 92 (14) 45-49 43 (10.6) 31 (12.4) 1.4 74 (11.3) 50-54 48 (11.9) 24 (9.6) 2.0 72 (11) 55-59 36 (8.9) 31 (12.4) 1.2 67 (10.2) 60-64 29 (7.2) 20 (8) 1.5 49 (7.5) ≥65 15 (3.7) 11 (4.4) 1.4 26 (4)

Table e-2A. Diagnostic delay for urban and rural MS patients with disease onset after 1993, the year the first MRI scan was installed on Crete

Urban Rural p-value Females, N 197 65 Males, N 109 55 0.05* aCurrent age, years 38.6 ±11.0 41.7 ± 11.6 0.008† (n) (306) (120) 2, Kotzamani

aAge at MS diagnosis, years 33.3 ± 10.8 35.2 ± 11.2 (n) (306) (120) aDiagnostic delay, years 1.4 ± 2.4 1.1 ± 1.8 (n) (306) (120) aRelapses from onset to diagnosis 1.4 ± 0.6 1.3 ± 0.6 (n) (282) (102) aEDSS at diagnosis 2.3 ± 1.0 2.6 ± 1.2 (n) (103) (28) aOnset to first specialist, years 1.0 ± 2.1 1.3 ± 2.3 (n) (208) (87) aOnset to first MRI scan, years 1.2 ± 2.3 1.3 ± 2.3 (n) (212) (86)

(n) represents the number of patients on whom data were available; aMean values ± SD;

* Pearson’s chi-squared; †Student’s independent samples t-test; only statistically significant

values (p<0.05) are shown in bold; EDSS, expanded disability status scale 3, Kotzamani

Table e-2B. Diagnostic delay for urban and rural MS patients with disease onset before 1993

Urban Rural p-value Females, n 64 31 Males, n 39 20 aCurrent age, years 51.9 ± 9.4 54.2 ± 11.6 (n) (103) (52) aAge at MS diagnosis, years 35.5 ± 11.6 37.3 ± 11.8 (n) (103) (52) aDiagnostic delay, years 6.6 ± 7.2 6.8 ± 7.5 (n) (103) (52) aRelapses from onset to diagnosis 1.8 ± 0.8 1.9 ± 0.8 (n) (88) (45) aOnset to first specialist, years 3.7 ± 6.0 4.0 ± 6.8 (n) (53) (31) aOnset to first MRI scan, years 5.5 ± 6.4 7.0 ± 6.8 (n) (56) (28) (n) represents the number of patients on whom data were available; aMean values ± SD; only

statistically significant values (p<0.05) are shown in bold. 4, Kotzamani

Table e- 3A. Comparison of urban MS patients with urban controls

MS cases, n/N (%) Controls, n/N (%) p-value* Milk consumption-childhood Fresh goat milk 60/218 100/342 (27.5%) (29.2%)

Pasteurized cow milk 131/218 180/342 (60.1%) (52.6%)

Fresh goat & pasteurized cow milk 27/218 62/342 (12.4%) (18.1%) Milk consumption-adulthood Fresh goat milk 8/164 6/240 (4.9%) (2.5%)

Pasteurized cow milk 151/164 208/240 (92.1%) (86.7%)

Fresh goat & pasteurized cow milk 5/164 26/240 0.008 (3.0%) (10.8%) 1Smoking Females, n (%) 121/224 109/276 0.002 (54.0%) (39.5%)

Males, n (%) 84/ 127 72/159 0.001 (66.1%) (45.3%) 1Alcohol Females, n (%) 71/189 77/276 0.03 (37.6%) (27.9%)

Males, n (%) 67/105 98/157 (63.8%) (62.4%)

1Vitamin use, n (%) 60/259 67/437 0.01 (23.2%) (15.3%)

1Oral contraceptives, n (%) 48/179 47/275 0.02 (26.8%) (17.1%)

Age at first childbirth, mean ± SD 25.6 ± 4.4 24.4 ± 5.1 0.03

1Traveling abroad, n (%) 150/311 184/436 (48.2) (42.2)

1Sunbathing, n (%) 141/259 231/438 (54.4%) (52.7%)

n: number of subjects; N: number of subjects on whom data were available;* Pearson’s chi-squared; only

statistically significant values (p<0.05) are shown in bold; 1Patients reported their exposure prior to the

first symptoms of MS.

Table e-3B. Comparison of rural MS cases and rural controls

MS cases, n/N (%) Controls, n/N (%) p-value* Milk consumption-childhood 5, Kotzamani

Fresh goat milk 55/114 68/136 (48.2%) (50.0%)

Pasteurized cow milk 43/114 45/136 (37.7%) (33.1%)

Fresh goat & pasteurized cow milk 16/114 23/136 (14.0%) (16.9%)

Milk consumption-adulthood Fresh goat milk 13/81 12/92 (16.0%) (13.0%)

Pasteurized cow milk 62/81 69/92 (76.5%) (75.0%)

Fresh goat & pasteurized cow milk 6/81 11/92 (7.5%) (12.0%)

1Smoking Females, n (%) 37/84 25/91 0.03 (44.0%) (27.5%)

Males, n (%) 42/67 33/65 (62.7%) (50.8%) 1Alcohol Females, n (%) 23/68 13/91 0.004 (33.8%) (14.3%)

Males, n (%) 30/53 48/65 0.05 (56.6%) (73.8%)

1Vitamin use, n (%) 29/129 31/156 (22.5%) (19.9%)

1Oral contraceptives, n (%) 11/75 11/91 (14.7%) (12.1%)

Age at first childbirth, mean ± SD 22.7 ± 4.6 22 ± 4.0

1Traveling abroad, n (%) 34/145 29/156 (23.4%) (18.6%)

1Sunbathing, n (%) 57/131 46/156 0.02 (43.5%) (29.5%) n: number of subjects; N: number of subjects on whom data were available;* Pearson’s chi-squared; only statistically significant values (p<0.05) are shown in bold; 1Patients reported their exposure prior to the first symptoms of MS.

Table e- 4A. Demographic data of MS patients and control subjects with residence on

Crete for at least 15 years

MS cases Controls p-value* Total, n 523 551 Females, n (%) 328 (62.7%) 342 (62.2%) Males, n (%) 195 (37.3%) 208 (37.8) Age (years) 6, Kotzamani

Females, mean ± SD 42.6 ± 12.3 44.2 ± 12.5 Males, mean ± SD 43.4 ± 13.0 44.5 ± 13.1 Childhood residence Urban, n (%) 228 (43.6%) 247/548 (45.1%) Rural, n (%) 295 (56.4%) 301/548 (54.9%) Current residence Urban, n (%) 359 (68.4%) 397 (72.1%) Rural, n (%) 164 (31.4%) 154 (27.9%) Years spent in village, mean ± SD 25.8 ±17.1 31.7 ± 18.5 <0.001 Siblings mean ± SD 2.2 ± 1.6 2.2 ± 1.5 Maternal siblings, mean ± SD 3.1 ± 2.1 3.7 ± 2.2 <0.001 Paternal siblings, mean ± SD 3.6 ± 2.2 3.8 ± 2.5 Age at first childbirth, mean ± SD 24.5 ± 4.6 23.7 ± 5.0 Age at menarche, mean ± SD 12.9 ± 1.5 12.8 ± 1.4

Table e-4B. Milk consumption and life-style habits of MS patients and controls with residence on Crete for at least 15 years

MS cases Controls p-value*

Milk consumption-childhood Fresh goat milk, n/N (%) 113/300 166/438 (37.7%) (37.9%)

Pasteurized cow milk, n/N (%) 148/300 192/438 (49.3%) (43.8%)

Fresh goat & Pasteurized cow milk, n/N (%) 39/300 80/438 (13.0%) (18.3%) Milk consumption-adulthood Fresh goat milk, n/N (%) 20/216 17/302 (9.3%) (6.0%)

Pasteurized cow milk, n/N (%) 185/216 247/302 (85.6%) (82.0%)

Fresh goat & Pasteurized cow milk, n/N (%) 11/216 37/302 0.006 (5.1%) (12.0%) 1Smoking Females, n/N (%) 139/276 120 <0.001 (50.4%) (35.2%) 7, Kotzamani

Males, n/N (%) 110/169 94/207 <0.001 (65.1%) (45.4%) 1Alcohol Females, n/N (%) 80/230 74/301 0.001 (34.8%) (24.6%)

Males, n/N (%) 86/137 120/197 (62.8%) (61.2%)

1Vitamin use, n/N (%) 82/349 90/549 0.009 (23.5%) (16.4%)

1Oral contraceptives, n/N (%) 49/229 51/340 0.06 (21.4%) (15.0%)

1Traveling abroad, n/N (%) 147/406 191/550 (36.2%) (34.7%)

1Sunbathing, n/N (%) 179/351 252/551 (51%) (45.7%) n: number of subjects; N: number of subjects on whom data were available; * Pearson’s chi-squared; only statistically significant values (p<0.05) are shown in bold; 1Patients reported their exposure prior to the first symptoms of MS. 8, Kotzamani

Table e-5. Occupation of MS patients and controls and their parents Production Professional Agriculture workers/ Clerical College or technical animal transport sales & Household high school administrative husbandry & equipment service, n (%) students managerial, fishermen, operators & n (%) n (%) n (%) n (%) laborers, n (%) FEMALES Patients 51 (18.5%) 98 (35.5%) 17 (6.2%) 13 (4.7%) 65 (23.6%) 32 (11.6%) Controls 82 (22.7%) 136 (37.7%) 17 (4.7%) 14 (3.9%) 98 (27.1%) 13 (3.6%) p-value 0.2 0.6 0.4 0.6 0.3 Patients’ mothers 31 (6.8%) 70 (15.3%) 107 (23.4%) 15 (3.3%) 234 (51.2%) Controls’ mothers 21 (3.6%) 91 (15.8%) 166 (28.8%) 20 (3.5%) 278 (54.3%) p-value 0.02 0.8 0.05 0.9 0.3 MALES Patients 17 (9.7%) 68 (38.6%) 20 (11.4%) 42 (23.9%) 2 (1.1%) 24 (13.6%) Controls 69 (31.8%) 79 (36.4%) 19 (8.8%) 42 (19.4%) 1 (0.5%) 6 (2.8%) p-value <0.001 0.6 0.4 0.3 0.3 Patients’ fathers 61 (13.5%) 117 (25.8%) 170 (37.5%) 102 (22.5%) 3 (0.7%) Controls’ fathers 69 (11.7%) 141 (23.8%) 245 (41.4%) 128 (21.6%) 1 (0.2%) p-value 0.4 0.5 0.1 0.8 0.2

The MS patients’ occupations are those at the time of the disease onset, whereas the occupations of the controls are at the time of the study.

Table e-6. Education Level of MS patients and controls

MS patients Controls Primary school 81/400 (20.3%) 103/589 (17.5%) Junior high school 53/400 (13.3%) 79/589 (13.4%) High school 127/400 (31.8%) 195/589 (33.1%) 9, Kotzamani

College/University 135/400 (33.8%) 207/589 (35.1%) Master/PhD diploma 4/400 (1%) 5/589 (0.8%)

Chi-square analysis revealed that the two groups were not different (p=0.86)