Background
Setting
Methods
Data collection and analysis
Ethical issues
Results
Characteristics of cohort participants
Males (N = 3,291) | Females (N = 4,052) | |
---|---|---|
SOCIO-DEMOGRAPHIC/ECONOMIC FACTORS
| ||
Age (years)
1
| ||
< 20 | 1278 (38.8%) | 1222 (30.2%) |
20-29 | 598 (18.2%) | 830 (20.5%) |
30-39 | 489 (14.9%) | 721 (17.8%) |
40-49 | 375 (11.4%) | 526 (13.0%) |
50-59 | 243 (7.4%) | 343 (8.5%) |
≥ 60 | 308 (9.4%) | 410 (10.1%) |
Marital status
| ||
Never married | 1678 (51.0%) | 1366 (33.7%) |
Married with 1 wife | 1163 (35.3%) | 1361 (33.6%) |
Married with > 1 wife | 148 (4.5%) | 464 (11.5%) |
Separated/divorced/widowed | 302 (9.2%) | 861 (21.2%) |
Age at first marriage (if ever married)
1
| ||
< 16 years | 9 (0.6%) | 403 (15.0%) |
16-19 years | 292 (18.1%) | 1534 (57.2%) |
20-24 years | 703 (43.6%) | 539 (20.1%) |
25+ years | 552 (34.2%) | 125 (4.7%) |
Doesn't remember | 56 (3.5%) | 81 (3.0%) |
Median (IQR) age at first marriage (years) | 22 (20-25) | 18 (16-20) |
Education level
1
| ||
Less than primary | 193 (5.9%) | 463 (11.4%) |
Incomplete primary | 1565 (47.6%) | 1677 (41.4%) |
Primary | 658 (20.0%) | 823 (20.3%) |
Junior/secondary | 720 (21.9%) | 935 (23.1%) |
Above secondary | 153 (4.6%) | 153 (3.8%) |
SES score tertile
1
| ||
Low | 852 (27.8%) | 953 (25.4%) |
Middle | 1085 (35.5%) | 1396 (37.2%) |
High | 1123 (36.7%) | 1407 (37.5%) |
SEXUAL BEHAVIOUR, AMONG THOSE WHO HAVE EVER HAD SEX
| ||
(N = 2100)
|
(N = 3024)
| |
Age at first sex (years)
2
| ||
< 15 | 163 (7.8%) | 360 (11.9%) |
15-16 | 395 (18.9%) | 1028 (34.0%) |
17-18 | 659 (31.4%) | 1044 (34.5%) |
19-20 | 405 (19.3%) | 332 (11.0%) |
21+ | 205 (9.8%) | 67 (2.2%) |
Doesn't remember | 269 (12.8%) | 192 (6.4%) |
Median (IQR) age at first sex (years) | 18 (16-20) | 17 (15-18) |
Partners in past year
2
| ||
None | 431 (20.5%) | 949 (31.4%) |
1 | 1241 (59.1%) | 2038 (67.4%) |
2 | 300 (14.3%) | 33 (1.1%) |
3+ | 128 (6.1%) | 3 (0.1%) |
Lifetime partners
2
| ||
1 | 245 (11.7%) | 985 (32.7%) |
2 | 264 (12.7%) | 940 (31.2%) |
3-4 | 476 (22.8%) | 842 (28.0%) |
5+ | 928 (44.5%) | 214 (7.1%) |
Doesn't remember | 174 (8.3%) | 30 (1.0%) |
Median (IQR) lifetime partners | 4 (2-8) | 2 (1-3) |
Last time had sex with any partner
2
| ||
In last month | 1388 (66.1%) | 1642 (54.3%) |
2-6 months | 227 (10.8%) | 342 (11.3%) |
7-12 months | 53 (2.5%) | 90 (3.0%) |
> 12 months | 431 (20.5%) | 949 (31.4%) |
Sex with an extramarital partner in past year
3
| ||
Yes | 201 (15.3%) | 17 (0.9%) |
CONCURRENCY INDICATORS, AMONG THOSE HAVING SEX IN PAST YEAR
| ||
(N = 1668)
|
(N = 2074)
| |
Concurrency at 6m before interview
| ||
Yes | 280 (16.8%) | 11 (0.5%) |
Any concurrency in last 12 m
| ||
Yes | 340 (20.4%) | 19 (0.9%) |
Any concurrency in last 12 m among those with > 1 partner
4
| ||
Yes | 340 (79.6%) | 19 (52.8%) |
Any concurrency in last 12 m, excluding polygynous partnerships
| ||
Yes | 230 (13.8%) | 19 (0.9%) |
CONCURRENCY INDICATORS, AMONG ALL AGED 15-49
| ||
(N = 2273)
|
(N = 2855)
| |
Concurrency at 6 m before interview
| ||
Yes | 223 (9.8%) | 11 (0.4%) |
Any concurrency in last 12 m
| ||
Yes | 281 (12.4%) | 19 (0.7%) |
Any concurrency in last 12 m, excluding polygynous partnerships
| ||
Yes | 211 (9.3%) | 19 (0.7%) |
HIV STATUS, AMONG ALL PARTICIPANTS
5
| ||
Negative | 3124 (95.5%) | 3731 (92.6%) |
Positive | 148 (4.5%) | 298 (7.4%) |
Prevalence and characteristics of concurrency
Overall concurrency
Males (N = 340) | Females (N = 19) | |
---|---|---|
Number of overlapping partnerships
| ||
Two | 283 (83.2%) | 19 (100%) |
Three | 57 (16.8%) | 0 |
Type of relationships
1
| ||
All are spouses (polygynous) | 110 (32.4%) | - |
Spouse and/or regular partners only | 171 (50.3%) | 14 (73.7%) |
Spouse/regular with casual partner | 53 (15.6%) | 4 (21.1%) |
All are casual partners | 6 (1.8%) | 0 |
Concurrent partnership still ongoing
| ||
Yes | 247 (72.7%) | 8 (42.1%) |
Condom use at last sex with concurrent partners
| ||
Did not use with any | 206 (60.6%) | 11 (57.9%) |
Used with some | 108 (31.8%) | 5 (26.3%) |
Used with all | 26 (7.6%) | 3 (15.8%) |
Condom use at last sex by type of relationship
| ||
Among those with spousal concurrent partners only
| ||
Did not use with any | 100 (90.9%) | - |
Used with some | 9 (8.2%) | - |
Used with all | 1 (0.9%) | - |
Among those with regular non-spousal concurrent partners
2
| ||
Did not use with any | 92 (53.8%) | 7 (50.0%) |
Used with some | 64 (37.4%) | 4 (28.6%) |
Used with all | 15 (8.8%) | 3 (21.4%) |
Among those with a casual concurrent partner
3
| ||
Did not use with any | 14 (23.7%) | 3 (75.0%) |
Used with some | 35 (59.3%) | 1 (25.0%) |
Used with all | 10 (16.9%) | 0 |
HIV seropositive
4
| ||
Overall | 28 (8.2%) | 7 (36.8%) |
Among those with 2 concurrent partnerships | 23 (8.2%) | 7 (36.8%) |
Among those with 3 concurrent partnerships | 5 (8.8%) | - |
Among those with spousal concurrent partners only | 4 (3.7%) | - |
Among those with regular non-spousal concurrent partners | 16 (9.4%) | 5 (35.7%) |
Among those with a casual concurrent partner | 8 (13.8%) | 2 (50.0%) |
HIV seroprevalence in spouse
5
| ||
Overall | 25 (8.3%) | 4 (66.7%) |
Among those with 2 concurrent partnerships | 21 (8.5%) | 4 (66.7%) |
Among those with 3 concurrent partnerships | 4 (7.4%) | - |
Among those with spousal concurrent partners only | 15 (9.0%) | - |
Among those with regular non-spousal concurrent partners | 8 (7.4%) | 3 (60.0%) |
Among those with a casual concurrent partner | 2 (7.7%) | 1 (100%) |
Polygynous concurrency
Concurrency excluding polygyny
Factors associated with concurrency
Overall concurrency
Any concurrency | Concurrency excluding polygyny | |||
---|---|---|---|---|
n reporting/ N (%) | Unadjusted OR (95% CI) | n reporting/ N (%) | Unadjusted OR (95% CI) | |
SOCIO-DEMOGRAPHIC/ECONOMIC FACTORS
| ||||
Age (years)
| P < 0.001 | P < 0.001 | ||
< 30 | 92/537 (17.1%) | 1 | 84/537 (15.6%) | 1 |
30-39 | 100/440 (22.7%) | 1.42 [1.04, 1.95] | 81/440 (18.4%) | 1.22 [0.87, 1.70] |
40-49 | 89/326 (27.3%) | 1.82 [1.30, 2.53] | 46/326 (14.1%) | 0.89 [0.60, 1.31] |
50+ | 59/365 (16.2%) | 0.93 [0.65, 1.33] | 19/365 (5.2%) | 0.30 [0.18, 0.50] |
Marital status
| P < 0.001 | P = 0.08 | ||
Never married | 47/295 (15.9%) | 1.17 [0.82, 1.66] | 47/295 (15.9%) | 1.17 [0.82, 1.66] |
Married with 1 wife | 155/1108 (14.0%) | 1 | 155/1108 (14.0%) | 1 |
Married with > 1 wife | 120/143 (83.9%) | 32.1 [19.9, 51.7] | 10/143 (7.0%) | 0.46 [0.24, 0.90] |
Separated/divorced/widowed | 18/122 (14.8%) | 1.06 [0.63, 1.80] | 18/122 (14.8%) | 1.06 [0.63, 1.80] |
Age at first marriage
1
| P < 0.01 | P = 0.11 | ||
22+ years | 146/774 (18.9%) | 1 | 94/774 (12.1%) | 1 |
< 22 years | 141/559 (25.2%) | 1.45 [1.12, 1.89] | 85/559 (15.2%) | 1.30 [0.95, 1.78] |
Education level
| P = 0.04 | P = 0.20 | ||
Incomplete primary or less | 125/709 (17.6%) | 1 | 87/709 (12.3%) | 1 |
Primary | 103/436 (23.6%) | 1.45 [1.08, 1.94] | 70/436 (16.1%) | 1.37 [0.97, 1.92] |
Junior or above | 112/522 (21.5%) | 1.28 [0.96, 1.70] | 73/522 (14.0%) | 1.16 [0.83, 1.62] |
SES score tertile
| P < 0.001 | P = 0.002 | ||
Low | 51/384 (13.3%) | 1 | 32/384 (8.3%) | 1 |
Middle | 121/571 (21.2%) | 1.76 [1.23, 2.51] | 86/571 (15.1%) | 1.95 [1.27, 2.99] |
High | 129/553 (23.3%) | 1.99 [1.39, 2.83] | 83/553 (15.0%) | 1.94 [1.26, 2.99] |
SEXUAL BEHAVIOUR
| ||||
Age at first sex (years)
1
| P < 0.001 | P < 0.001 | ||
18+ years | 134/802 (16.7%) | 1 | 89/802 (11.1%) | 1 |
< 18 years | 160/645 (24.8%) | 1.64 [1.27, 2.13] | 117/645 (18.1%) | 1.78 [1.32, 2.39] |
Lifetime partners
1
| P < 0.001 | P < 0.001 | ||
< 5 males | 64/721 (8.9%) | 1 | 43/721 (6.0%) | 1 |
5+ males | 235/793 (29.6%) | 4.32 [3.21, 5.83] | 163/793 (20.6%) | 4.08 [2.87, 5.81] |
Can't remember | 40/147 (27.2%) | 3.84 [2.46, 5.99] | 23/147 (15.6%) | 2.92 [1.70, 5.03] |
Condom use with last partner
| P = 0.82 | P = 0.01 | ||
No | 296/1444 (20.5%) | 1 | 187/1444 (12.9%) | 1 |
Yes | 43/217 (19.8%) | 0.96 [0.67, 1.37] | 42/217 (19.0%) | 1.61 [1.11, 2.34] |
Casual partner in past 12 m
| P < 0.001 | P < 0.001 | ||
No | 272/1480 (18.4%) | 1 | 162/1480 (10.9%) | 1 |
Yes | 68/188 (36.2%) | 2.52 [1.82, 3.48] | 68/188 (36.2%) | 4.61 [3.28, 6.47] |
Problem drinking
| P < 0.01 | P = 0.001 | ||
No | 312/1590 (19.6%) | 1 | 208/1590 (13.1%) | 1 |
Yes | 26/74 (35.1%) | 2.22 [1.36, 3.63] | 21/74 (28.4%) | 2.63 [1.56, 4.45] |
HIV serostatus
| P = 0.22 | P = 0.02 | ||
Negative | 310/1543 (20.1%) | 1 | 205/1543 (13.3%) | 1 |
Positive | 28/112 (25.0%) | 1.33 [0.85, 2.07] | 24/112 (21.4%) | 1.78 [1.11, 2.86] |
Spouse's HIV serostatus
2
| P = 0.54 | P = 0.98 | ||
Negative | 276/1049 (26.3%) | 1 | 124/1049 (11.8%) | 1 |
Positive | 25/85 (29.4%) | 1.17 [0.72, 1.92] | 10/85 (11.8%) | 0.99 [0.50, 1.96] |
Any concurrency | Concurrency excluding polygyny | |
---|---|---|
Adjusted OR1
(95% CI) | Adjusted OR1
(95% CI) | |
SOCIO-DEMOGRAPHIC/ECONOMIC FACTORS
| ||
Age (years)
|
P < 0.001
|
P < 0.001
|
< 30 |
1
|
1
|
30-39 |
1.29 [0.81, 2.05]
|
1.21 [0.77, 1.93]
|
40-49 |
0.97 [0.57, 1.62]
|
0.85 [0.50, 1.43]
|
50+ |
0.39 [0.22, 0.70]
|
0.27 [0.14, 0.51]
|
Marital status
|
P < 0.001
|
P = 0.07
|
Never married |
0.88 [0.51, 1.51]
|
0.79 [0.46, 1.36]
|
Married with 1 wife |
1
|
1
|
Married with > 1 wife |
43.5 [25.2, 74.8]
|
0.41 [0.19, 0.88]
|
Separated/divorced/widowed |
0.76 [0.41, 1.40]
|
0.75 [0.40, 1.40]
|
Age at first marriage
1
| P = 0.27 | P = 0.29 |
22+ years | 1 | 1 |
< 22 years | 1.22 [0.86, 1.73] | 1.22 [0.85, 1.77] |
Education level
| P = 0.61 | P = 0.82 |
Incomplete primary or less | 1 | 1 |
Primary | 1.19 [0.81, 1.75] | 1.07 [0.72, 1.60] |
Junior or above | 1.16 [0.79, 1.71] | 1.14 [0.76, 1.69] |
SES score tertile
|
P = 0.01
|
P = 0.01
|
Low |
1
|
1
|
Middle |
1.72 [1.11, 2.65]
|
1.85 [1.17, 2.94]
|
High |
1.85 [1.20, 2.87]
|
1.92 [1.21, 3.05]
|
SEXUAL BEHAVIOUR
| ||
Age at first sex
2
| P = 0.41 | P = 0.41 |
18 years or older | 1 | 1 |
< 18 years | 1.16 [0.82, 1.63] | 1.16 [0.81, 1.66] |
Lifetime partners
2
|
P < 0.001
|
P < 0.001
|
Less than 5 |
1
|
1
|
5 or more |
4.30 [2.95, 6.27]
|
4.55 [3.03, 6.82]
|
Can't remember |
3.35 [1.82, 6.17]
|
4.05 [2.13, 7.69]
|
Condom use with last partner
| P = 0.14 | P = 0.11 |
No | 1 | 1 |
Yes | 1.45 [0.89, 2.36] | 1.51 [0.92, 2.47] |
Casual partner in past 12 months
|
P < 0.001
|
P < 0.001
|
No |
1
|
1
|
Yes |
3.73 [2.40, 5.82]
|
3.90 [2.13, 7.69]
|
Problem drinking
| P = 0.15 | P = 0.14 |
No | 1 | 1 |
Yes | 1.61 [0.86, 3.00] | 1.64 [0.87, 3.12] |
Polygynous concurrency
Concurrency excluding polygyny
Association of concurrency and HIV prevalence
Overall concurrency
Odds ratio (95% CI) | p-value | |
---|---|---|
OUTCOME = HIV SEROPREVALENCE
EXPOSURE = ANY CONCURRENCY IN PAST 12 MONTHS
| ||
Among men reporting sex in past 12 months (N = 1655)
| ||
Model 1
| ||
Any concurrency in the past 12 months | 1.33 (0.85-2.08) | P = 0.22 |
Model 2
| ||
Any concurrency in the past 12 months | 1.13 (0.67-1.89) | P = 0.64 |
Adjusted for: age group, marital status and lifetime partners2
| ||
Model 3
| ||
Any concurrency in the past 12 months | 1.04 (0.62-1.77) | P = 0.88 |
Adjusted for: age group, marital status, lifetime partners2 and casual partner in past 12 months | ||
OUTCOME = HIV SEROPREVALENCE
EXPOSURE = CONCURRENCY WITH POLYGYNOUS PARTNERS ONLY
| ||
Among men reporting sex in past 12 months (N = 1655)
| ||
Model 1
| ||
Concurrency with polygynous partner in past 12 months | 0.50 (0.18-1.39) | P = 0.14 |
Model 2
| ||
Concurrency with polygynous partner in past 12 months | 0.40 (0.14-1.11) | P = 0.07 |
Adjusted for lifetime partners2 in past 12 months | ||
OUTCOME = HIV SEROPREVALENCE
EXPOSURE = CONCURRENCY EXCLUDING POLYGYNY
| ||
Among men reporting sex in past 12 months (N = 1655)
| ||
Model 1
| ||
Concurrency with non-spousal partner in past 12 months | 1.78 (1.11-2.86) | P = 0.02 |
Model 2
| ||
Concurrency with non-spousal partner in past 12 months | 1.36 (0.82-2.25) | P = 0.25 |
Adjusted for lifetime partners2 and casual partner in past 12 months | ||
OUTCOME = HIV SEROPREVALENCE IN SPOUSE
EXPOSURE = ANY CONCURRENCY IN PAST 12 MONTHS
| ||
Among wives of men reporting sex in past 12 months (N = 1134)
| ||
Model 1
| ||
Any concurrency by husband in the past 12 months | 1.17 (0.71-1.92) | 0.54 |
Model 2
3
| ||
Any concurrency by husband in the past 12 months | 0.97 (0.59-1.59) | 0.90 |
Adjusted for husband's lifetime partners2
|