Background
Methods
Study design and population
Laboratory methods
Statistical analyses
-
calculated the overall and age- and sex-specific HSV1 and HSV2 seroprevalences and their 95% confidence intervals (CIs);
-
used Pearson’s χ2 test to investigate the potential associations between seroprevalence and sex, age, and region of residence (East or West Germany); and
-
investigated potential determinants associated with HSV1/2 seropositivity by calculating the PRs using log-binomial regression. Because the questions concerning sexual behavior differed for men and women, we performed the univariable and multivariable analyses separately for each sex. If a p-value was <0.2 in the univariable analysis, we included that variable in a stepwise forward variable selection to find a suitable multivariable model. As only a small number of behavioral variables were available within the survey, we set the cutoff for the p-value at 0.2 to take these variables sufficiently into account. Two-way interaction terms were generated for biologically relevant covariate pairs, and retained in the model if significant (p ≤ 0.05).
Results
Characteristics of the study participants
Weighted seroprevalence of HSV1
Weighted seroprevalence of HSV2
Factors associated with HSV1 seropositivity
Variables | N | Weighteda prevalence % | (95% CI) | Univariable Analysis | Multivariable Analysis | ||
---|---|---|---|---|---|---|---|
PRb(95% CI) |
p-value | PRc(95% CI) |
p-value | ||||
Age group (years) | |||||||
18–24 | 283 | 51.4 | (45.3–57.5) | Ref | Ref | Ref | Ref |
25–34 | 400 | 70.4 | (64.6–75.5) |
1.4 (1.2–1.6)
|
0.000
| 1.2 (1.0–1.4) | 0.057 |
35–44 | 519 | 82.4 | (77.9–86.1) |
1.6 (1.4–1.8)
|
0.000
|
1.4 (1.2–1.6)
|
0.000
|
45–54 | 714 | 86.5 | (83.1–89.2) |
1.7 (1.5–1.9)
|
0.000
|
1.4 (1.2–1.7)
|
0.000
|
55–64 | 630 | 91.8 | (88.7–94.1) |
1.8 (1.6–2.0)
|
0.000
|
1.5 (1.3–1.8)
|
0.000
|
65+ | 895 | 93.1 | (90.4–95.1) |
1.8 (1.6–2.0)
|
0.000
|
1.6 (1.3–1.8)
|
0.000
|
CASMIN educational classification | |||||||
Low | 1117 | 90.0 | (87.6–91.9) |
1.3 (1.2–1.4)
|
0.000
|
1.2 (1.1–1.3)
|
0.000
|
Medium | 1772 | 79.3 | (76.4–82.0) |
1.2 (1.1–1.2)
|
0.000
|
1.2 (1.1–1.3)
|
0.000
|
High | 531 | 68.8 | (63.7–73.5) | Ref | Ref | Ref | Ref |
Income | |||||||
Low | 991 | 83.4 | (80.1–86.2) | Ref | Ref | − | − |
Medium | 2031 | 82.0 | (79.7–84.2) | 1.0 (0.9–1.0) | 0.481 | − | − |
High | 419 | 76.9 | (70.6–82.2) | 0.9 (0.8-1.0) | 0.066 | − | − |
Employment situation | |||||||
Worker | 827 | 91.2 | (88.5–93.4) |
1.1 (1.1–1.2)
|
0.000
|
1.1 (1.0–1.1)
|
0.004
|
Employee | 1611 | 81.4 | (78.5–83.9) | Ref | Ref | Ref | Ref |
Civil servant | 169 | 70.3 | (60.5–78.5) |
0.9 (0.8–1.0)
|
0.036
| 0.9 (0.8–1.1) | 0.482 |
Free-lance/self-reliant | 233 | 84.9 | (77.9–90.0) | 1.0 (1.0–1.1) | 0.232 | 1.0 (1.0–1.1) | 0.379 |
Family worker | 64 | 87.5 | (75.2–94.1) | 1.1 (1.0–1.2) | 0.201 | 1.0 (0.9–1.2) | 0.551 |
other | 124 | 51.8 | (40.9–62.5) |
0.6 (0.5–0.8)
|
0.000
| 0.8 (0.6–1.0) | 0.086 |
Smoking, currently | |||||||
Daily | 643 | 84.2 | (80.0–87.7) | 1.0 (1.0–1.1) | 0.266 |
1.1 (1.0–1.1)
|
0.035
|
Occasionally | 179 | 75.1 | (67.2–81.6) | 0.9 (0.8-1.0) | 0.090 |
1.1 (1.0–1.2)
|
0.023
|
No, not anymore | 825 | 82.1 | (77.7–85.7) | 1.0 (1.0–1.1) | 0.841 | 1.0 (0.9–1.1) | 0.898 |
Never smoked | 1776 | 81.6 | (79.1–83.9) | Ref | Ref | Ref | Ref |
Number of other children in household during childhood | |||||||
0 | 369 | 76.6 | (70.6–81.7) | Ref | Ref | − | − |
1–2 | 1478 | 74.9 | (71.9–77.7) | 1.0 (0.9–1.1) | 0.579 | − | − |
> 2 | 1594 | 90.6 | (88.5–92.3) |
1.2 (1.1–1.3)
|
0.000
| − | − |
Visit of nursery during childhood | |||||||
No | 801 | 87.9 | (84.4–90.7) |
1.2 (1.1–1.2)
|
0.000
| − | − |
Yes | 1705 | 74.8 | (71.9–77.5) | Ref | Ref | − | − |
Degree of urbanization | |||||||
Rural | 607 | 83.8 | (78.3–88.2) | Ref | Ref | − | − |
Provincial | 844 | 84.0 | (80.1–87.3) | 1.0 (0.9–1.1) | 0.956 | − | − |
Urban | 963 | 80.2 | (76.3–83.6) | 1.0 (0.8–1.0) | 0.238 | − | − |
Metropolitan | 1027 | 81.1 | (77.7–84.0) | 1.0 (0.9–1.0) | 0.347 | − | − |
Region of residence | |||||||
West Germany | 2350 | 81.2 | (78.9–83.2) | Ref | Ref | − | − |
East Germany (including Berlin) | 1091 | 85.0 | (81.4–88.0) | 1.0 (1.0-1.1) | 0.052 | − | − |
German mother tongue | |||||||
Yes | 3170 | 81.0 | (78.9–83.0) | Ref | Ref | Ref | Ref |
No | 242 | 88.4 | (82.2–92.6) |
1.1 (1.0–1.2)
|
0.000
|
1.1 (1.1–1.2)
|
0.000
|
Number of sexual partners in last 12 months | |||||||
None | 1051 | 85.4 | (82.3–88.0) |
1.0 (1.0–1.1)
|
0.043
| − | − |
1 | 2110 | 81.5 | (78.9–83.9) | Ref | Ref | − | − |
2–3 | 153 | 62.3 | (53.1–70.7) |
0.8 (0.7–0.9)
|
0.001
| − | − |
> 3 | 24 | 76.6 | (49.1–91.8) | 0.9 (0.7–1.2) | 0.668 | − | − |
HSV2 serostatus | |||||||
HSV2 seronegative | 2262 | 81.6 | (79.1–83.8) | Ref | Ref | − | − |
HSV2 seropositive | 323 | 88.9 | (83.7–92.6) |
1.1 (1.0–1.2)
|
0.004
| − | − |
Current use of birth control methods | |||||||
Yes | 978 | 72.0 | (68.5–75.3) | Ref | Ref | − | − |
No | 1523 | 84.1 | (81.6–86.3) |
1.2 (1.1–1.2)
|
0.000
| − | − |
Which birth control method | |||||||
-Contraceptive pill | |||||||
Yes | 470 | 67.2 | (62.1–72.0) | Ref | Ref | − | − |
No | 478 | 77.1 | (72.1–81.5) |
1.1 (1.0–1.3)
|
0.005
| − | − |
-Condoms | |||||||
Yes | 287 | 71.8 | (65.3–77.6) | Ref | Ref | − | − |
No | 661 | 72.3 | (67.9–76.4) | 1.0 (0.9–1.1) | 0.891 | − | − |
Miscarriage | |||||||
None | 2008 | 77.1 | (74.5–79.5) | Ref | Ref | − | − |
1 or more | 549 | 88.3 | (83.8–91.6) |
1.1 (1.1–1.2)
|
0.000
| − | − |
Abortion | |||||||
None | 2047 | 77.3 | (74.8–79.7) | Ref | Ref | − | − |
1 or more | 471 | 88.5 | (84.0–91.9) |
1.1 (1.1–1.2)
|
0.000
| − | − |
Variables | N | Weighteda prevalence % | (95% CI) | Univariable Analysis | Multivariable Analysis | ||
---|---|---|---|---|---|---|---|
PRb (95% CI) |
p-value | PRc (95% CI) |
p-value | ||||
Age group (years) | |||||||
18–24 | 289 | 42.2 | (35.8–48.9) | Ref | Ref | Ref | Ref |
25–34 | 364 | 64.5 | (58.4–70.2) |
1.5 (1.3–1.8)
|
0.000
|
1.5 (1.2–1.8)
|
0.000
|
35–44 | 448 | 72.8 | (67.1–77.9) |
1.7 (1.5–2.0)
|
0.000
|
1.7 (1.4–2.0)
|
0.000
|
45–54 | 627 | 81.2 | (77.1–84.6) |
1.9 (1.6–2.3)
|
0.000
|
1.9 (1.6–2.2)
|
0.000
|
55–64 | 559 | 85.9 | (81.8–89.2) |
2.0 (1.7–2.4)
|
0.000
|
2.0 (1.7–2.3)
|
0.000
|
65+ | 899 | 90.6 | (87.5–92.9) |
2.1 (1.8–2.5)
|
0.000
|
1.9 (1.6–2.3)
|
0.000
|
CASMIN educational classification | |||||||
Low | 1045 | 85.2 | (82.2–87.7) |
1.2 (1.1–1.3)
|
0.000
|
1.2 (1.1–1.2)
|
0.000
|
Medium | 1407 | 69.7 | (66.4–72.8) | 1.0 (0.9–1.1) | 0.967 | 1.1 (1.0–1.2) | 0.062 |
High | 714 | 69.8 | (65.0–74.2) | Ref | Ref | Ref | Ref |
Income | |||||||
Low | 855 | 79.1 | (75.6–82.2) | Ref | Ref | − | − |
Medium | 1837 | 74.2 | (71.6–76.6) |
0.9 (0.9–1.0)
|
0.015
| − | − |
High | 494 | 72.3 | (67.1–76.9) |
0.9 (0.8–1.0)
|
0.022
| − | − |
Employment situation | |||||||
Worker | 1109 | 80.2 | (77.0–83.0) |
1.1 (1.0–1.2)
|
0.004
| − | − |
Employee | 1033 | 73.2 | (69.4–76.8) | Ref | Ref | − | − |
Civil servant | 224 | 76.2 | (68.3–82.6) | 1.0 (0.9–1.2) | 0.462 | − | − |
Free-lance/self-reliant | 394 | 78.6 | (72.0–84.0) |
1.1 (1.0-1.2)
|
0.133
| − | − |
Family worker | 6 | 100.0 |
1.4 (1.3–1.4)
|
0.002
| − | − | |
Other | 93 | 48.0 | (35.7–60.5) |
0.7 (0.5–0.9)
|
0.000
| − | − |
Smoking, currently | |||||||
Daily | 706 | 76.1 | (72.0–79.8) |
1.1 (1.0–1.2)
|
0.040
| 1.1 (1.0–1.1) | 0.060 |
Occasionally | 201 | 74.0 | (65.4–81.1) | 1.0 (0.9–1.2) | 0.440 |
1.1 (1.0–1.3)
|
0.013
|
No, not anymore | 1181 | 79.5 | (76.2–82.4) |
1.1 (1.1–1.2)
|
0.000
| 1.0 (0.9–1.1) | 0.985 |
Never smoked | 1081 | 70.6 | (66.7–74.2) | Ref | Ref | Ref | Ref |
Number of other children in household during childhood | |||||||
0 | 341 | 70.0 | (63.5–75.7) | Ref | Ref | Ref | Ref |
1–2 | 1323 | 64.8 | (61.7–67.7) | 0.9 (0.8-1.0) | 0.127 | 0.9 (0.9–1.0) | 0.184 |
> 2 | 1522 | 88.1 | (86.0–90.0) |
1.3 (1.1–1.4)
|
0.000
|
1.1 (1.0–1.2)
|
0.039
|
Visit of nursery during childhood | |||||||
No | 726 | 80.5 | (76.8–83.7) | Ref | Ref | − | − |
Yes | 152 | 67.1 | (64.1–70.0) |
1.2 (1.1–1.3)
|
0.000
| − | − |
Degree of urbanization | |||||||
Rural | 636 | 77.2 | (73.2–80.7) | Ref | Ref | − | − |
Provincial | 799 | 77.3 | (73.3–80.8) | 1.0 (0.9–1.1) | 0.974 | − | − |
Urban | 866 | 72.8 | (68.8–76.4) | 0.9 (0.9-1.0) | 0.105 | − | − |
Metropolitan | 885 | 75.3 | (71.6–78.8) | 1.0 (0.9–1.0) | 0.490 | − | − |
Region of residence | |||||||
West Germany | 2151 | 74.6 | (72.3–76.7) | Ref | Ref | Ref | Ref |
East Germany (including Berlin) | 1035 | 78.4 | (74.5–81.9) | 1.1 (1.0-1.1) | 0.075 |
1.1 (1.0–1.1)
|
0.003
|
German mother tongue | |||||||
Yes | 2952 | 73.8 | (71.7–75.8) | Ref | Ref | Ref | Ref |
No | 208 | 86.7 | (79.6–91.6) |
1.2 (1.1–1.3)
|
0.000
|
1.2 (1.1–1.3)
|
0.000
|
Number of sexual partners in last 12 months | |||||||
None | 632 | 74.1 | (68.6–78.9) | 1.0 (0.9–1.0) | 0.414 | − | − |
1 | 2113 | 76.4 | (74.0–78.6) | Ref | Ref | − | − |
2–3 | 205 | 65.2 | (57.1–72.5) |
0.9 (0.7–1.0)
|
0.012
| − | − |
> 3 | 98 | 68.8 | (57.0–78.6) | 0.9 (0.8-1.1) | 0.193 | − | − |
HSV2 serostatus | |||||||
HSV2 seronegative | 2221 | 74.8 | (72.5–76.9) | Ref | Ref | − | − |
HSV2 seropositive | 207 | 77.4 | (69.6–83.6) | 1.0 (0.9–1.1) | 0.472 | − | − |
Use of condoms | |||||||
Generally | 398 | 59.3 | (53.7–64.7) | Ref | Ref | − | − |
Occasionally | 400 | 67.5 | (61.6–73.0) |
1.1 (1.0-1.3)
|
0.034
| − | − |
No | 1881 | 78.0 | (77.3–82.4) |
1.3 (1.2–1.5)
|
0.000
| − | − |
N/a | 372 | 79.1 | (72.6–84.3) |
1.3 (1.2–1.5)
|
0.000
| − | − |
Factors associated with HSV2 seropositivity
Variables | N | Weighteda prevalence % | (95% CI) | Univariable Analysis | Multivariable Analysis | ||
---|---|---|---|---|---|---|---|
PRb (95% CI) |
p-value | PRc (95% CI) |
p-value | ||||
Age group (years) | |||||||
18–24 | 227 | 2.0 | (0.8–4.8) | Ref | Ref | Ref | Ref |
25–34 | 277 | 7.6 | (4.5–12.5) |
3.9 (1.4–11.1)
|
0.012
|
3.5 (1.2–10.4)
|
0.021
|
35–44 | 405 | 11.5 | (7.9–16.4) |
5.9 (2.3–15.2)
|
0.000
|
5.6 (2.1–14.7)
|
0.001
|
45–54 | 535 | 16.1 | (12.8–20.0) |
8.2 (3.2–21.2)
|
0.000
|
7.3 (2.7–19.5)
|
0.000
|
55–64 | 461 | 15.5 | (12.0–19.8) |
7.9 (3.3–18.9)
|
0.000
|
8.0 (3.1–20.5)
|
0.000
|
65+ | 680 | 12.3 | (9.4–15.6) |
6.3 (2.4–16.3)
|
0.000
|
6.5 (2.5–17.0)
|
0.000
|
CASMIN educational classification | |||||||
Low | 841 | 10.5 | (8.2–13.3) | 1.2 (0.7–1.8) | 0.522 | − | − |
Medium | 1335 | 12.6 | (10.6–15.0) | 1.4 (0.9-2.1) | 0.131 | − | − |
High | 392 | 9.1 | (6.3–13.0) | Ref | Ref | − | − |
Income | |||||||
Low | 750 | 10.8 | (8.2–14.1) | Ref | Ref | − | − |
Medium | 1529 | 11.7 | (9.8–13.8) | 1.1 (0.8–1.5) | 0.652 | − | − |
High | 306 | 14.5 | (10.2–20.2) | 1.3 (0.9–2.1) | 0.204 | − | − |
Employment situation | |||||||
Worker | 623 | 12.4 | (9.6–16.0) | 1.0 (0.7–1.3) | 0.884 | − | − |
Employee | 1174 | 12.7 | (10.5–15.4) | Ref | Ref | − | − |
Civil servant | 128 | 14.5 | (8.6–23.4) | 1.1 (0.7–1.9) | 0.623 | − | − |
Free-lance/self-reliant | 174 | 13.2 | (8.3–20.5) | 1.0 (0.6–1.7) | 0.874 | − | − |
Family worker | 47 | 5.3 | (1.4–18.8) | 0.4 (0.1–1.6) | 0.202 | − | − |
Other | 96 | 4.0 | (1.4–10.8) |
0.3 (0.1–0.9)
|
0.033
| − | − |
Smoking, currently | |||||||
Daily | 486 | 15.2 | (11.8–19.2) |
1.5 (1.1–2.1)
|
0.006
|
1.6 (1.0–2.4)
|
0.033
|
Occasionally | 133 | 8.7 | (4.9–15.1) | 0.9 (0.5–1.6) | 0.673 | 1.1 (0.5–2.3) | 0.847 |
No, not anymore | 607 | 13.4 | (10.6–16.5) |
1.3 (1.0–1.8)
|
0.031
| 1.2 (0.9–1.7) | 0.226 |
Never smoked | 1345 | 9.9 | (8.1–12.0) | Ref | Ref | Ref | Ref |
Number of other children in household during childhood | |||||||
0 | 272 | 12.5 | (8.2–18.6) | Ref | Ref | − | − |
1–2 | 1125 | 9.6 | (8.0–11.6) | 0.8 (0.5–1.2) | 0.221 | − | − |
> 2 | 1188 | 13.6 | (11.1–16.5) | 1.1 (0.7–1.7) | 0.728 | − | − |
Visit of nursery during childhood | |||||||
No | 614 | 14.5 | (11.7–17.8) |
1.5 (1.1–2.0)
|
0.008
| − | − |
Yes | 1264 | 9.7 | (7.8–12.0) | Ref | Ref | − | − |
HSV1 serostatus | |||||||
HSV1 seronegative | 431 | 7.3 | (4.8–11.1) | Ref | Ref | − | − |
HSV1 seropositive | 2154 | 12.6 | (10.9–14.5) |
1.7 (1.1–2.7)
|
0.017
| − | − |
Degree of urbanization | |||||||
Rural | 424 | 9.6 | (6.2–14.6) | Ref | Ref | − | − |
Provincial | 651 | 11.3 | (8.5–14.7) | 1.2 (0.7–2.0) | 0.539 | − | − |
Urban | 792 | 10.1 | (8.0–12.7) | 1.1 (0.6–1.7) | 0.835 | − | − |
Metropolitan | 718 | 14.4 | (11.7–17.7) | 1.5 (0.9-2.4) | 0.095 | − | − |
Region of residence | |||||||
West Germany | 1778 | 10.8 | (9.2–12.7) | Ref | Ref | − | − |
East Germany (including Berlin) | 807 | 14.6 | (11.5–18.4) |
1.3 (1.0–1.8)
|
0.037
| − | − |
German mother tongue | |||||||
Yes | 2390 | 11.5 | (9.9–13.3) | Ref | Ref | − | − |
No | 172 | 10.9 | (6.9–16.8) | 0.9 (0.8–1.5) | 0.825 | − | − |
Number of sexual partners in last 12 months | |||||||
None | 788 | 12.7 | (10.2–15.7) | 1.1 (0.8–1.5) | 0.500 | − | − |
1 | 1588 | 11.5 | (9.6–13.7) | Ref | Ref | − | − |
2–3 | 116 | 12.0 | (5.3–24.8) | 1.0 (0.5–2.3) | 0.917 | − | − |
> 3 | 17 | 10.3 | (1.4–49.0) | 0.9 (0.1–6.2) | 0.912 | − | − |
Current use of birth control methodsd
| |||||||
Yes | 740 | 8.5 | (6.3–11.3) | Ref | Ref | − | − |
No | 1140 | 14.1 | (12.0–16.6) |
1.7 (1.2–2.3)
|
0.003
| − | − |
Which birth control method | |||||||
-Contraceptive Pill | |||||||
Yes | 363 | 7.0 | (4.4–10.8) | Ref | Ref | − | − |
No | 353 | 9.6 | (6.5–14.0) | 1.4 (0.8–2.4) | 0.264 | − | − |
-Condoms | |||||||
Yes | 217 | 8.0 | (4.7–13.4) | Ref | Ref | − | − |
No | 499 | 8.4 | (5.7–12.3) | 1.0 (0.5–2.1) | 0.892 | − | − |
Miscarriage | |||||||
None | 1504 | 10.4 | (8.5–12.6) | Ref | Ref | − | − |
1 or more | 424 | 15.9 | (12.1–20.6) |
1.5 (1.1–2.1)
|
0.009
| − | − |
Abortion | |||||||
None | 1538 | 10.1 | (8.4–12.2) | Ref | Ref | Ref | Ref |
1 or more | 351 | 20.1 | (15.3–25.9) |
2.0 (1.4–2.7)
|
0.000
|
1.5 (1.1–2.2)
|
0.023
|
Variables | N | Weighteda prevalence % | (95% CI) | Univariable Analysis | Multivariable Analysis | ||
---|---|---|---|---|---|---|---|
PRb (95% CI) |
p-value | PRc (95% CI) |
p-value | ||||
Age group (years) | |||||||
18–24 | 222 | 1.2 | (0.4–3.9) | Ref | Ref | Ref | Ref |
25–34 | 283 | 2.8 | (1.4–5.3) | 2.3 (0.6–9.0) | 0.247 | 2.0 (0.5–7.8) | 0.314 |
35–44 | 343 | 4.3 | (2.2–8.2) | 3.5 (0.9-13.9) | 0.075 | 3.1 (0.8–12.0) | 0.100 |
45–54 | 477 | 9.4 | (6.3–13.8) |
7.7 (2.5–24.0)
|
0.000
|
5.4 (1.7–17.1)
|
0.004
|
55–64 | 418 | 11.4 | (8.2–15.7) |
9.3 (2.8–31.2)
|
0.000
|
6.9 (2.1–23.1)
|
0.002
|
65+ | 685 | 11.0 | (8.1–14.8) |
9.0 (2.6–31.1)
|
0.001
| d | d |
CASMIN educational classification | |||||||
Low | 806 | 8.7 | (6.4–11.8) | 1.1 (0.7–1.7) | 0.768 | − | − |
Medium | 1069 | 5.7 | (4.3–7.5) | 0.7 (0.4-1.1) | 0.109 | − | − |
High | 538 | 8.2 | (5.8–11.4) | Ref | Ref | − | − |
Income | |||||||
Low | 656 | 6.1 | (4.3–8.6) | Ref | Ref | − | − |
Medium | 1414 | 7.2 | (5.7–9.2) | 1.2 (0.8–1.8) | 0.374 | − | − |
High | 358 | 9.5 | (6.1–14.4) | 1.6 (0.9-2.8) | 0.127 | − | − |
Employment situation | |||||||
Worker | 844 | 7.9 | (5.8–10.7) | 1.0 (0.6–1.5) | 0.890 | − | − |
Employee | 773 | 8.1 | (6.0–10.9) | Ref | Ref | − | − |
Civil servant | 183 | 7.0 | (3.7–12.8) | 0.9 (0.4–1.7) | 0.659 | − | − |
Free-lance/self-reliant | 293 | 8.5 | (5.6–12.5) | 1.0 (0.6–1.8) | 0.880 | − | − |
Family worker | 4 | − | − | − | − | − | − |
Other | 64 | 0.9 | (0.1–6.5) |
0.1 (0.1–0.1)
|
0.031
| − | − |
Smoking, currently | |||||||
Daily | 524 | 6.3 | (4.3–9.2) | 0.9 (0.6–1.5) | 0.761 | − | − |
Occasionally | 151 | 3.8 | (1.7–8.2) | 0.6 (0.2-1.3) | 0.182 | − | − |
No, not anymore | 899 | 9.0 | (6.8–11.7) | 1.3 (1.0-1.8) | 0.089 | − | − |
Never smoked | 843 | 6.8 | (5.1–9.0) | Ref | Ref | − | − |
Number of other children in household during childhood | |||||||
0 | 257 | 5.5 | (3.2–9.3) | Ref | Ref | − | − |
1–2 | 999 | 5.8 | (4.3–7.9) | 1.1 (0.6–1.9) | 0.839 | − | − |
> 2 | 1172 | 8.9 | (7.2–11.1) | 1.6 (0.9-2.8) | 0.087 | − | − |
Visit of nursery during childhoodd
| |||||||
No | 561 | 10.8 | (7.9–14.5) |
2.4 (1.7–3.5)
|
0.000
|
1.5 (1.0–2.2)
|
0.036
|
Yes | 1153 | 4.4 | (3.4–5.8) | Ref | Ref | Ref | Ref |
HSV1 serostatus | |||||||
HSV1 seronegative | 548 | 6.5 | (4.6–9.0) | Ref | Ref | − | − |
HSV1 seropositive | 1880 | 7.4 | (6.0–9.1) | 1.1 (0.8–1.7) | 0.494 | − | − |
Degree of urbanization | |||||||
Rural | 435 | 6.5 | (3.2–12.6) | Ref | Ref | − | − |
Provincial | 620 | 6.1 | (3.9–9.4) | 0.9 (0.4–2.1) | 0.875 | − | − |
Urban | 712 | 7.7 | (5.7–10.3) | 1.2 (0.6–2.5) | 0.660 | − | − |
Metropolitan | 661 | 7.9 | (6.2–10.2) | 1.2 (0.6–2.5) | 0.582 | − | − |
Region of residence | |||||||
West Germany | 1675 | 6.6 | (5.2–8.4) | Ref | Ref | − | − |
East Germany (including Berlin) | 753 | 9.2 | (7.0–11.9) | 1.4 (1.0-2.0) | 0.070 | − | − |
German mother tongue | |||||||
Yes | 151 | 7.4 | (6.1–8.9) | Ref | Ref | − | − |
No | 2256 | 5.7 | (3.2–9.9) | 0.8 (0.4–1.4) | 0.394 | − | − |
Number of sexual partners in last 12 months | |||||||
None | 486 | 8.3 | (5.5–12.3) | 1.1 (0.7–1.8) | 0.594 | − | − |
1 | 1613 | 7.3 | (5.8–9.1) | Ref | Ref | − | − |
2–3 | 155 | 5.3 | (2.6–10.7) | 0.7 (0.3–1.5) | 0.395 | − | − |
> 3 | 73 | 6.9 | (2.8–16.2) | 0.9 (0.4–2.4) | 0.905 | − | − |
Use of condoms | |||||||
Generally | 289 | 2.7 | (1.5–4.9) | Ref | Ref | Ref | Ref |
Occasionally | 314 | 6.8 | (4.2–10.8) |
2.5 (1.1–5.7)
|
0.024
|
2.3 (1.0–5.1)
|
0.050
|
No | 1454 | 8.0 | (6.4–9.9) |
3.0 (1.6–5.5)
|
0.001
| 1.7 (0.9–3.2) | 0.105 |
N/a | 275 | 9.9 | (5.7–16.5) |
3.7 (1.6–8.6)
|
0.003
| 1.6 (0.6–4.7) | 0.345 |