Chlamydia reinfection rates among 16–24-year-old women per 100 person-years by setting of recruitment and population characteristics, England, March 2002–August 2003
| Characteristic | Recruited from general practice | Recruited from family planning | Recruited from GUM | |||
|---|---|---|---|---|---|---|
| n (no.positive) | Reinfection rate per 100 py (95% CI) | n (no.positive) | Reinfection rate per 100 py (95% CI) | n (no.positive) | Reinfection rate per 100 py (95% CI) | |
| GUM, genitourinary medicine; py, person-years; ref, reference group for significance test. | ||||||
| *The rate of new sexual partner change for the time period immediately preceding reinfection. | ||||||
| †Result of significance test suggests reinfection rate is different from the reference group at p<0.05 level. | ||||||
| ‡Rate uses known partners as the denominator. | ||||||
| §Rate uses reported partners as the denominator. | ||||||
| Total recruited | 125 | 198 | 224 | |||
| Total retained for follow-up | 101 (22) | 29.9 (19.7 to 45.4) | 159 (30) | 22.3 (15.6 to 31.8) | 157 (26) | 21.1 (14.3 to 30.9) |
| Retention rate | 81% | 80% | 70% | |||
| Reason for attendance (baseline) | ||||||
| Attended for symptoms | 8 (1) | 15.3 (2.2 to 108.9) | 17 (3) | 17.9 (5.8 to 55.5) | 30 (7) | 33.5 (15.9 to 70.2) |
| Other reason, but reported symptoms | 36 (11) | 50.2 (27.8 to 90.6) | 54 (9) | 19.8 (10.3 to 38.1) | 51 (8) | 23.3 (11.6 to 46.5) |
| Asymptomatic | 57 (10) | 22.1 (11.9 to 41.2) | 88 (18) | 24.8 (15.6 to 39.3) | 76 (11) | 16.2 (8.9 to 29.2) |
| Age group (years) | ||||||
| 16–17 | 12 (5) | 86.2 (35.9 to 207.2)† | 60 (13) | 29.4 (17.0 to 50.6) | 25 (6) | 32.3 (14.5 to 71.9) |
| 18–20 | 41 (7) | 22.8 (10.9 to 47.9) | 65 (12) | 19.9 (11.3 to 35.0) | 84 (15) | 22.8 (13.7 to 37.8) |
| 21–24 | 48 (10) | 26.9 (14.5 to 50.1) ref | 34 (5) | 16.6 (6.9 to 39.9) | 48 (5) | 12.8 (5.3 to 30.8) |
| Ethnic group | ||||||
| White | 73 (17) | 33.8 (21.0 to 54.3) | 148 (29) | 22.8 (15.8 to 32.8) | 118 (23) | 24.2 (16.1 to 36.5) |
| Non-white | 0 | No events | 1 (0) | No events | 4 (0) | No events |
| Unknown | 28 (5) | 21.5 (8.9 to 51.6) | 10 (1) | 15.4 (2.2 to 109.3) | 35 (3) | 11.5 (3.7 to 35.6) |
| Ever had chlamydia (baseline) | ||||||
| Yes | 8 (1) | 17.8 (2.5 to 126.5) | 10 (0) | No events | 19 (5) | 33.8 (14.0 to 81.1) |
| No | 78 (18) | 31.7 (19.9 to 50.2) | 126 (24) | 21.9 (14.7 to 32.7) | 123 (19) | 19.5 (12.5 to 30.6) |
| Condom use at last sexual intercourse | ||||||
| Yes | 12 (2) | 21.7 (5.4 to 86.8) | 29 (7) | 27.6 (13.2 to 57.9) | 22 (3) | 21.2 (6.8 to 65.8) |
| No | 73 (16) | 28.6 (17.5 to 46.7) | 88 (15) | 19.0 (11.5 to 31.6) | 98 (20) | 25.1 (16.2 to 38.9) |
| Symptoms (yes, past 6 months) | No is ref | No is ref | No is ref | |||
| Cystitis (urinary tract infection) | 15 (6) | 68.2 (30.6 to 151.8)† | 20 (4) | 26.2 (9.8 to 69.7) | 13 (2) | 15.7 (3.9 to 62.9) |
| Frequent urination | 8 (3) | 48.8 (15.7 to 151.3) | 13 (4) | 44.8 (16.8 to 119.5) | 17 (4) | 23.3 (8.7 to 62.1) |
| Abdominal pain | 13 (4) | 46.7 (17.5 to 124.5) | 19 (4) | 22.7 (8.5 to 60.4) | 22 (9) | 69.6 (36.2 to 133.7)† |
| Bleeding between periods | 9 (3) | 40.5 (13.1 to 125.6) | 8 (4) | 52.4 (19.7 to 139.6) | 12 (4) | 42.5 (15.9 to 113.2) |
| Bleeding after sexual intercourse | 6 (2) | 90.7 (22.7 to 362.8) | 2 (1) | 38.8 (5.5 to 275.6) | 7 (4) | 86.2 (32.4 to 229.8)† |
| Pain during sexual intercourse | 7 (1) | 23.9 (3.4 to 169.6) | 11 (2) | 17.5 (4.4 to 69.9) | 18 (7) | 60.1 (28.6 to 126.0)† |
| Discharge | 12 (4) | 44.7 (16.8 to 119.0) | 20 (5) | 31.9 (13.3 to 76.7) | 25 (9) | 39.0 (20.3 to 75.0) |
| None | 35 (7) | 26.3 (12.5 to 55.1) | 53 (8) | 17.7 (8.9 to 35.5) | 45 (4) | 11.8 (4.4 to 31.6) |
| Recent rate of partner change per 6 months* | ||||||
| No male sexual partner change | 54 (10) | 23.7 (12.8 to 44.1) ref | 58 (4) | 7.0 (2.6 to 18.6) ref. | 73 (11) | 18.3 (10.1 to 33.0) ref |
| 1 new male sexual partner | 11 (0) | No events | 24 (6) | 33.8 (15.2 to 75.2)† | 16 (1) | 8.4 (1.2 to 59.6) |
| 2 new male sexual partners | 14 (7) | 92.5 (44.1 to 194.0)† | 18 (7) | 35.5 (16.9 to 74.6)† | 20 (9) | 64.3 (33.5 to 123.6)† |
| 3 new male sexual partners | 1 (1) | 126.8 (17.9 to 900.3) | 8 (3) | 83.6 (27.0 to 259.3)† | 5 (1) | 34.8 (4.9 to 246.9) |
| ⩾4 new male sexual partners | 6 (1) | 28.3 (4.0 to 201.2) | 11 (3) | 43.4 (14.0 to 134.7)† | 4 (1) | 22.1 (3.1 to 157.0) |
| Patient management for initial positive test | ||||||
| Patient treatment of initial positive test | ||||||
| Azithromycin | 84 (21) | 35.3 (23.0 to 54.2) | 136 (26) | 22.4 (15.3 to 32.9) | 104 (17) | 21.8 (13.6 to 35.1) |
| Other regimen | 15 (1) | 8.8 (1.2 to 62.8) | 22 (4) | 21.3 (8.0 to 56.9) | 47 (9) | 21.2 (11.1 to 40.8) |
| Partner management details for initial positive test | ||||||
| Partner treatment rate‡ | ||||||
| 100% of known partners treated | 62 (11) | 23.4 (13.0 to 42.3) | 65 (7) | 11.5 (5.5 to 24.1) ref | 75 (11) | 16.7 (9.3 to 30.2) |
| <100% of known partners treated | 38 (11) | 41.9 (23.2 to 75.7) | 91 (22) | 30.2 (19.9 to 45.9)† | 77 (15) | 27.3 (16.5 to 45.4) |
| Effective partner treatment rate§ | ||||||
| 100% of reported partners treated | 65 (11) | 22.2 (12.3 to 40.1) ref | 77 (10) | 14.3 (7.7 to 26.5) ref | 84 (12) | 16.6 (9.4 to 29.2) |
| <100% of reported partners treated | 28 (10) | 53.2 (28.6 to 98.8)† | 71 (18) | 32.6 (20.6 to 51.8)† | 61 (14) | 31.7 (18.8 to 53.5) |
| Effective partner treatment rate controlling for condom use at last sexual intercourse | ||||||
| Used condoms at last sexual intercourse | ||||||
| 100% of reported partners treated | 8 (2) | 34.4 (8.6 to 137.5) | 15 (5) | 40.3 (16.8 to 96.8) ref | 15 (3) | 38.1 (12.3 to 118.3) |
| <100% of reported partners treated | 3 (0) | No events | 13 (2) | 16.3 (4.1 to 65.2) | 6 (0) | No events |
| Did not use condoms at last sexual intercourse | ||||||
| 100% of reported partners treated | 50 (8) | 20.8 (10.4 to 41.6) | 42 (4) | 9.5 (3.6 to 25.4)† | 51 (6) | 12.7 (5.7 to 28.3) |
| <100% of reported partners treated | 19 (7) | 49.6 (23.7 to 104.1) | 40 (11) | 36.1 (20.0 to 65.2) | 38 (14) | 50.4 (29.8 to 85.1) |