Table I.
Baseline socio–demographic, behavioural and biological characteristics of women, overall and by HIV status, Durban, South Africa, 2004/2007
| Variable | Total (n = 242) | HIV Positive (n = 25) | HIV Negative (n = 217) | Test statistic = valuea | p-value |
|---|---|---|---|---|---|
| Demographic data | |||||
| Age in years (Mean, ±SD) | 34.3 (10.47) | 30.0 (10.37) | 34.8 (10.39) | t=2.20 | 0.029 |
| Age group (in years) % (n) | |||||
| 18–24 | 26.54% (64) | 44.0% (11) | 24.4% (53) | Fprob=0.023 | 0.053 |
| ≥ 25 | 73.6% (178) | 56.0% (14) | 75.6% (164) | ||
| Number of dependents % (n) | |||||
| 0 | 23.2% (56) | 16.0% (4) | 24.1% (52) | Fprob=0.143 | 0.460 |
| ≥ 1 | 76.8% (185) | 84% (21) | 75.9% (164) | ||
| Educational level % (n) | |||||
| ≤Grade 8 | 35.5% (86) | 20.0% (5) | 37.3% (81) | Fprob=0.042 | 0.121 |
| > Grade 8 | 64.5% (156) | 80.0% (20) | 62.7% (136) | ||
| Risk behaviour | |||||
| Age in years at sexual debut (Mean, ±SD) | 17.0 (2.38) | 16.5 (1.76) | 17.1 (2.44) | t=1.18 | 0.239 |
| Relationship status % (n) | |||||
| No partner or Stable/Married partner | 43.2% (104) | 24.0% (6) | 45.4% (98) | Fprob=0.021 | 0.054 |
| Many partners | 56.6% (137) | 76.0% (19) | 54.4% (118) | ||
| Mean sex acts per month (±SD) | 10.3 (6.78) | 10.3 (5.03) | 10.3 (6.97) | t=−0.01 | 0.994 |
| Type of sex act % (n) | |||||
| Ever had vaginal sex | 100% (242) | 100% (25) | 100% (217) | – | – |
| Ever had anal sex | 34.6% (83) | 44.0% (11) | 33.5% (72) | Fprob=0.100 | 0.374 |
| Ever had oral sex | 25.3% (61) | 24.0% (6) | 25.5% (55) | Fprob=0.192 | 1.000 |
| Condom use at last sex act % (n) | |||||
| Yes | 58.7% (142) | 64.0% (16) | 58.1% (126) | Fprob=0.147 | 0.670 |
| No | 41.3% (100) | 36.0% (9) | 41.9% (91) | ||
| Any contraception % (n) | 79.7% (192) | 68.0% (17) | 81.0% (175) | Fprob=0.064 | 0.185 |
| Contraception type % (n) | |||||
| Condom only | 41.5% (100) | 36.0% (9) | 42.1% (91) | Fprob=0.030 | 0.808 |
| Hormonal | 30.7% (74) | 32.0% (8) | 30.5 (66) | ||
| None/Otherb | 27.8% (67) | 32.0% (8) | 27.2% (59) | ||
| Douching after sex % (n) | 9.5% (23) | 4.0% (1) | 10.2% (22) | Fprob=0.210 | 0.483 |
| Sex after alcohol or substance use % (n) | |||||
| Yes | 26.9% (65) | 20.0% (5) | 27.7% (60) | Fprob=0.144 | 0.484 |
| No | 73.1% (177) | 80.0% (20) | 72.4% (157) | ||
| Sex for compensation | |||||
| Self-reported sex workers % (n) | 78.9% (191) | 72.0% (18) | 79.7% (173) | Fprob=0.129 | 0.436 |
| Years in sex work (Median, IQR) | 3.0 (1.3 – 8.3) | 2.5 (1.0 – 7.0) | 3.0 (1.3 – 9.0) | Z=−1.36 | 0.179 |
| Age at start of sex work (Mean, ±SD) | 28.2 (9.02) | 27.2 (10.16) | 28.3 (8.92) | t=0.49 | 0.625 |
| Days per week perform sex work (Mean, ±SD) | 2.9 (1.40) | 2.9 (1.55) | 2.9 (1.39) | t=−0.21 | 0.835 |
| Sites worked per year (Mean, ±SD) | 2.6 (1.30) | 2.8 (0.86) | 2.6 (1.33) | t=−1.08 | 0.291 |
| Clients per day (Mean, ±SD) | 2.5 (1.19) | 2.6 (1.24) | 2.5 (1.19) | t=−0.36 | 0.722 |
| Clients in the past week (Mean, ±SD) | 3.1 (3.83) | 2.4 (2.53) | 3.1 (3.94) | t=1.01 | 0.323 |
| Short sessions per week (Mean, ±SD) | 4.2 (4.05) | 3.6 (4.68) | 4.3 (3.99) | t=0.63 | 0.527 |
| Overnight stays per week (Mean, ±SD) | 1.1 (1.20) | 1.4 (1.34) | 1.0 (1.19) | t=−1.46 | 0.147 |
| Condom use in the last month % (n) | |||||
| Always | 38.2% (73) | 27.8% (5) | 39.3% (68) | Fprob=0.033 | 0.650 |
| Sometimes | 42.9% (82) | 50.0% (9) | 42.2% (73) | ||
| Never | 18.9% (36) | 22.2% (4) | 18.5% (32) | ||
| HIV knowledge | |||||
| How safe is anal sex compared to peno–vaginal sex? % (n) | |||||
| Same or more risk | 62.8% (152) | 56.0% (14) | 63.6% (138) | Fprob=0.002 | 0.278 |
| Less risk or don't know | 37.2% (90) | 44.0% (11) | 36.4% (79) | ||
| How safe is oral sex compared to peno–vaginal sex? % (n) | |||||
| Same or more risk | 71.8% (173) | 68.0% (17) | 72.2% (156) | Fprob=0.163 | 0.644 |
| Less risk or don't know | 28.2% (68) | 32% (8) | 27.8 (60) | ||
| If you have an STI are you more likely to get HIV? % (n) | |||||
| Yes | 71.1% (172) | 80.0% (20) | 70.1% (152) | Fprob=0.085 | 0.665 |
| No | 1.7% (4) | 0.0% (0) | 1.8% (4) | ||
| Only sometimes/unsure | 27.3% (66) | 20.0% (5) | 28.1% (61) | ||
| Do you think HIV can be treated? % (n) | |||||
| Yes | 95.0% (230) | 96.0% (24) | 94.9% (206) | Fprob=0.159 | 0.516 |
| No | 2.1% (5) | 4.0% (1) | 1.8% (4) | ||
| Unsure | 2.9% (7) | 0.0% (0) | 3.2% (7) | ||
| Clinical evaluation | |||||
| Ever pregnant prior to HIV % (n) | |||||
| Yes | 10.3% (25) | 12.0% (3) | 10.1% (22) | Fprob=0.244 | 0.730 |
| No | 89.7% (217) | 88.0% (22) | 89.9% (195) | ||
| Laboratory parameters | |||||
| Haemoglobin g/dL (Mean, ±SD) | 12.7 (1.29) | 12.8 (1.43) | 12.7 (1.27) | t=−0.51 | 0.613 |
| Eosinophils 1 × 109/L (Mean, ±SD) | 0.2 (0.24) | 0.3 (0.25) | 0.2 (0.24) | t=−0.81 | 0.420 |
| Albumin g/L(Mean, ±SD) | 44.7 (3.57) | 44.8 (3.32) | 44.7 (3.60) | t=−0.02 | 0.981 |
| Vitamin B12 pg/mL (Mean, ± SD) | 291.0 (93.14) | 327.6 (112.19) | 287.0 (90.25) | t=−2.00 | 0.047 |
| Folate ng/mL (Mean, ±SD) | 22.4 (8.45) | 20.8 (8.54) | 22.6 (8.45) | t=0.94 | 0.346 |
| Serum iron μmol/L (Mean, ±SD) | 12.3 (6.41) | 12.1 (5.36) | 12.3 (6.53) | t=0.16 | 0.877 |
| Random glucose mmol/L (Mean, ±SD) | 5.2 (2.02) | 4.7 (0.85) | 5.3 (2.11) | t=2.72 | 0.008 |
| Sodium mmol/L (Mean, ±SD) | 137.1 (2.22) | 138.2 (2.08) | 137.0 (2.21) | t=−2.66 | 0.008 |
| Potassium mmol/L (Mean, ± SD) | 4.0 (0.32) | 4.1 (0.41) | 4.0 (0.32) | t=−0.35 | 0.730 |
| Chloride mmol/L (Mean, ±SD) | 103.0 (2.55) | 103.9 (1.98) | 102.9 (2.59) | t=−1.93 | 0.054 |
| Calcium mmol/L (Mean, ±SD) | 2.4 (0.12) | 2.4 (0.09) | 2.4 (0.12) | t=−0.67 | 0.501 |
| Phosphate mmol/L (Mean, ±SD) | 1.1 (0.18) | 1.1 (0.17) | 1.0 (0.18) | t=−1.43 | 0.155 |
| HIV negative CD4+ count cells/μl (Median, IQR) | 888 (742 – 1132) | 969 (855 – 1068) | 878 (738 – 1132) | Z=0.76 | 0.446 |
| HIV negative CD3+ count cells/μl (Median, IQR) | 1493 (1202 – 1839) | 1522 (1324–1857) | 1486 (1197 – 1822) | Z=0.58 | 0.564 |
| HIV negative CD8+ count cells/μl (Median, IQR) | 517 (402 – 688) | 500 (420–760) | 520 (402–680) | Z=−0.04 | 0.966 |
| Bacterial vaginosis % (n) | 52.7% (127/241) | 68.0% (17) | 50.9% (110/216) | Fprob=0.047 | 0.139 |
| Sexually transmitted infectionc % (n) | 31.3% (75/240) | 44.0% (11) | 29.8% (64/217) | Fprob=0.063 | 0.172 |
a
Test statistic are: t=t-tests or Z=Wilcoxon Rank Sums (Normal Approximation), for continuous variables; Fprob=Fisher's exact test hypergeometric probability, for categorical data
b
Female sterilisation or rhythm/calendar method
c
Any STI present if participant tested positive for syphilis antibodies or Trichomonasvaginalis, Neisseria gonorrhoeae, Mycoplasma genitalium, Chlamydia trachomatis or herpes simplex virus (HSV) type II (PCR)