Table 2.
Crude and multivariate analysis of HIV incidence associated factors and comparison of incidence rates between the cohorts
| Fisher folk cohort | General population cohort | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| HIV incident | Crude analysis | Multivariate analysis | HIV incident | Crude analysis | Multivariate analysis | Comparison of incidence rates between the cohorts | |||||||||
| Characteristic | Category | Cases | PYAR | RR (95% CI)/100 | RR (95% CI) | RR (95% CI) | p Value | Cases | PYAR | RR (95% CI)/100 | RR (95% CI) | RR (95% CI) | p Value | RR (95% CI)/100 | p Value |
| All participants | 36 | 596.1 | 6.04 (4.36 to 8.37) | 20 | 3589.6 | 0.56 (0.36 to 0.86) | 10.83 (6.11 to 19.76) | < 0.001 | |||||||
| Sex | Male | 17 | 391.5 | 4.34 (2.70 to 6.98) | Ref | Ref | 0.73 | 14 | 2823.8 | 0.50 (0.29 to 0.84) | Ref | Ref | 0.88 | 8.76 (4.06 to 19.19) | <0.001 |
| Female | 19 | 204.5 | 9.29 (5.93 to 14.56) | 1.97 (1.03 to 3.76) | 1.20 (0.39 to 3.63) | 6 | 765.8 | 0.78 (0.35 to 1.74) | 1.58 (0.61 to 4.10) | 0.92 (0.32 to 2.69) | 11.86 (4.55 to 36.28) | <0.001 | |||
| Age at enrolment | 30+ years | 14 | 236.0 | 5.93 (3.51 to 10.02) | Ref | Ref | 0.51 | 10 | 1821.7 | 0.55 (0.30 to 1.02) | Ref | Ref | 0.42 | 10.81 (4.46 to 27.19) | <0.001 |
| 25–29 years | 9 | 156.5 | 5.75 (2.99 to 11.05) | 0.96 (0.42 to 2.22) | 0.69 (0.30 to 1.59) | 5 | 559.5 | 0.89 (0.37 to 2.15) | 1.63 (0.56 to 4.73) | 1.84 (0.70 to 4.84) | 6.43 (1.94 to 24.44) | 0.001 | |||
| 18–24 years | 13 | 203.5 | 6.39 (3.71 to 11.00) | 1.03 (0.48 to 2.21) | 0.60 (0.22 to 1.63) | 5 | 1208.4 | 0.41 (0.17 to 0.99) | 0.75 (0.26 to 2.18) | 2.08 (0.39 to 10.98) | 15.44 (5.16 to 55.31) | <0.001 | |||
| Ethnicity | Muganda | 16 | 257.3 | 6.22 (3.81 to 10.15) | Ref | 10 | 2481.4 | 0.40 (0.22 to 0.75) | Ref | Ref | 0.05 | 15.43 (6.58 to 38.04) | <0.001 | ||
| Munyarwanda | 6 | 132.1 | 4.54 (2.04 to 10.11) | 0.73 (0.29 to 1.87) | 9 | 713.0 | 1.26 (0.66 to 2.43) | 3.14 (1.28 to 7.73) | 2.84 (1.18 to 6.83) | 3.60 (1.05 to 11.32) | 0.025 | ||||
| Other | 14 | 206.7 | 6.77 (4.01 to 11.44) | 1.09 (0.54 to 2.23) | 1 | 395.1 | 0.25 (0.04 to 1.80) | 0.63 (0.08 to 4.91) | 0.59 (0.07 to 4.76) | 26.76 (4.07 to 1131) | <0.001 | ||||
| Marital status | Married | 15 | 296.1 | 5.07 (3.05 to 8.40) | Ref | Ref | 0.2 | 18 | 2235.2 | 0.81 (0.51 to 1.28) | Ref | Ref | 0.003 | 6.29 (2.95 to 13.22) | <0.001 |
| Divorced/widowed | 15 | 127.5 | 11.76 (7.09 to 19.51) | 2.23 (1.09 to 4.57) | 1.17 (0.49 to 2.75) | 0 | 33.0 | 0 | – | – | – | ||||
| Single | 6 | 172.4 | 3.48 (1.56 to 7.75) | 0.68 (0.27 to 1.75) | 0.49 (0.17 to 1.42) | 2 | 1321.4 | 0.15 (0.04 to 0.61) | 0.19 (0.04 to 0.81) | 0.10 (0.01 to 0.76) | 22.99 (4.11 to 233) | <0.001 | |||
| Occupation | Fish-related | 19 | 394.8 | 4.81 (3.07 to 7.55) | Ref | Ref | 0.45 | 0 | 8.2 | 0 | – | – | |||
| Bar/restaurant/hotel worker | 11 | 54.4 | 20.24 (11.21 to 36.54) | 3.80 (1.82 to 7.96) | 1.83 (0.63 to 5.29) | 0 | 6.5 | 0 | – | – | |||||
| Farming | 0 | 7.8 | 0 | – | – | 14 | 2533.3 | 0.55 (0.33 to 0.93) | Ref | – | |||||
| Business/trade | 3 | 59.2 | 5.07 (1.63 to 15.71) | 0.99 (0.30 to 3.31) | 1.01 (0.26 to 3.88) | 2 | 293.2 | 0.68 (0.17 to 2.73) | 1.21 (0.28 to 5.29) | 7.43 (0.85 to 88.96) | 0.04 | ||||
| Formal/other | 2 | 45.2 | 4.42 (1.11 to 17.67) | 0.85 (0.20 to 3.63) | 0.64 (0.13 to 3.07) | 3 | 449.8 | 0.67 (0.21 to 2.07) | 1.18 (0.34 to 4.07) | 6.63 (0.55 to 57.91) | 0.076 | ||||
| Un employed | 1 | 34.7 | 2.88 (0.41 to 20.44) | 0.57 (0.07 to 4.33) | 0.42 (0.04 to 4.05) | 1 | 298.6 | 0.33 (0.05 to 2.38) | 0.60 (0.08 to 4.52) | 8.60 (0.11 to 675) | 0.208 | ||||
| Duration in community | ≥5 years | 5 | 245.2 | 2.04 (0.85 to 4.90) | Ref | Ref | <0.001 | 11 | 2484.2 | 0.44 (0.25 to 0.80) | Ref | Ref | 0.04 | 4.61 (1.25 to 14.38) | 0.013 |
| 1–4 years | 13 | 234.3 | 5.55 (3.22 to 9.56) | 2.59 (0.92 to 7.31) | 2.88 (0.95 to 8.78) | 5 | 945.2 | 0.53 (0.22 to 1.27) | 1.18 (0.41 to 3.38) | 1.60 (0.53 to 4.89) | 10.49 (3.51 to 37.58) | <0.001 | |||
| ≤1 year | 18 | 116.6 | 15.43 (9.72 to 24.5) | 6.87 (2.54 to 18.58) | 7.64 (2.36 to 24.67) | 4 | 160.2 | 2.50 (0.94 to 6.65) | 5.43 (1.72 to 17.10) | 5.98 (2.02 to 17.72) | 6.18 (2.04 to 25.11) | <0.001 | |||
| HIV risk profile factors | |||||||||||||||
| Number of sexual partners in the past year | Two or less | 1 | 47.4 | 2.11 (0.30 to 14.98) | Ref | 18 | 2984.9 | 0.60 (0.38 to 0.96) | Ref | 3.50 (0.08 to 22.16) | 0.294 | ||||
| More than two | 35 | 548.7 | 6.38 (4.58 to 8.88) | 3.09 (0.42 to 22.67) | 2 | 604.7 | 0.33 (0.08 to 1.32) | 0.54 (0.13 to 2.33) | 19.29 (4.95 to 165) | <0.001 | |||||
| Had unprotected sex in past 3 months/year | No | 8 | 219 | 3.65 (1.83 to 7.31) | Ref | Ref | 0.006 | 7 | 928.8 | 0.75 (0.36 to 1.58) | Ref | 4.85 (1.53 to 15.7) | 0.004 | ||
| Yes | 28 | 377.1 | 7.43 (5.13 to 10.75) | 2.13 (0.97 to 4.66) | 3.11 (1.27 to 7.66) | 13 | 2472.5 | 0.53 (0.31 to 0.91) | 0.70 (0.28 to 1.73) | 14.12 (7.08 to 29.7) | <0.001 | ||||
| Information missing | – | – | – | – | – | 0 | 188.3 | 0 | – | ||||||
| Alcohol use in past month | No | 8 | 151.9 | 5.27 (2.63 to 10.53) | Ref | 12 | 2499.6 | 0.48 (0.27 to 0.85) | Ref | 10.97 (3.89 to 29.18) | <0.001 | ||||
| Yes | 28 | 444.2 | 6.30 (4.35 to 9.13) | 1.26 (0.57 to 2.77) | 8 | 1090 | 0.73 (0.37 to 1.47) | 1.50 (0.61 to 3.67) | 8.59 (3.81 to 21.81) | <0.001 | |||||
| Current STI or STI in past 3 months | No | 11 | 272.2 | 4.04 (2.24 to 7.30) | Ref | Ref | 0.08 | – | – | – | – | – | – | ||
| Yes | 25 | 323.9 | 7.72 (5.22 to 11.42) | 1.85 (0.91 to 3.76) | 1.89 (0.90 to 4.00) | – | – | – | – | – | – | ||||
PYAR, person years at risk; RR, rate ratio; STI, sexually transmitted infection.