Table 2. Adjusted Odds ratios for individual KIR genes and KIR gene combinations in HIV-1 negative and HIV-1 positive women, outcome placental malaria (PM) status.
| HIV-1 negative women | HIV-1 positive women | |||||||
| Frequencies | Frequencies | |||||||
| PM+ (N = 116) | PM− (N = 93) | Adjusted OR | P | PM+ (N = 105) | PM− (N = 374) | Adjusted OR | P | |
| n (%) | n (%) | (95% CI) | n (%) | n (%) | (95%CI) | |||
| Individual KIR Genes | ||||||||
| KIR2DL1 | 116 (100) | 87 (93.6) | 15.45(>2.05)a | 0.006** | 101 (96.2) | 364 (97.3) | 0.69 (0.21–2.30) | 0.55 |
| KIR2DL2 | 57 (49.1) | 53 (57.0) | 0.81 (0.44–1.49) | 0.50 | 61 (58.1) | 192 (51.3) | 1.23 (0.78–1.92) | 0.37 |
| KIR2DL3 | 111 (95.7) | 78 (83.9) | 5.03 (1.63–15.54) | 0.005** | 79 (75.2) | 328 (87.7) | 0.41 (0.24–0.72) | 0.002** |
| KIR2DL4 | 116 (100) | 92 (98.9) | 0.49 (>0.01)a | 1.00 | 104 (99.1) | 372 (99.5) | 0.43 (0.04–5.14) | 0.51 |
| KIR2DL5 | 60 (51.7) | 57 (61.3) | 0.72 (0.39–1.32) | 0.29 | 66 (62.9) | 205 (54.8) | 1.38 (0.87–2.18) | 0.17 |
| KIR2DS1 | 25 (21.6) | 19 (20.4) | 1.27 (0.61–2.64) | 0.52 | 15 (14.3) | 84 (22.5) | 0.59 (0.32–1.08) | 0.086 |
| KIR2DS2 | 46 (39.7) | 46 (49.5) | 0.75 (0.41–1.36) | 0.34 | 52 (49.5) | 161 (43.1) | 1.24 (0.80–1.93) | 0.34 |
| KIR2DS3 | 25 (21.6) | 23 (24.7) | 0.78 (0.39–1.58) | 0.49 | 24 (22.9) | 66 (17.7) | 1.45 (0.85–2.48) | 0.18 |
| KIR2DS4 | 112 (96.6) | 85 (91.4) | 2.71 (0.73–10.11) | 0.14 | 100 (95.2) | 364 (97.3) | 0.52 (0.17–1.60) | 0.25 |
| KIR2DS5 | 43 (37.1) | 37 (39.8) | 0.99 (0.54–1.83) | 0.98 | 49 (46.7) | 167 (44.7) | 1.06 (0.68–1.66) | 0.79 |
| KIR3DL1 | 113 (97.4) | 89 (95.7) | 1.45 (0.29–7.30) | 0.65 | 104 (99.1) | 369 (98.7) | 1.42 (0.16–12.61) | 0.75 |
| KIR3DS1 | 19 (16.4) | 10 (10.8) | 1.77 (0.73–4.33) | 0.21 | 9 (8.6) | 50 (13.4) | 0.63 (0.30–1.35) | 0.23 |
| KIR Gene Combinations | ||||||||
| KIR2DL2/KIR2DL3c | ||||||||
| 2DL2/2DL3 | 52 (44.8) | 38 (40.9) | 1.10 (0.58–2.11) | 0.77 | 35 (33.3) | 147 (39.4) | 0.88 (0.53–1.46) | 0.61 |
| 2DL2/2DL2 | 5 (4.3) | 15 (16.1) | 0.21 (0.07–0.67) | 0.008** | 26 (24.8) | 45 (12.1) | 2.37 (1.30–4.30) | 0.005** |
| 2DL3/2DL3 | 59 (50.9) | 40 (43.0) | 1 | ……b | 44 (41.9) | 181 (48.5) | 1 | ……b |
| KIR2DS2/KIR2DL2 | ||||||||
| −/− | 58 (50.0) | 38 (40.9) | 1 | ……b | 43 (41.0) | 176 (47.1) | 1 | ……b |
| +/+ | 45 (38.8) | 44 (47.3) | 0.75 (0.40,–1.43) | 0.86 | 51 (28.6) | 155 (32.4) | 0.95 (0.57–1.61) | 0.86 |
| +/− | 1 (0.9) | 2 (2.2) | 0.91 (0.08–11.04) | 0.94 | 1 (1.0) | 6 (1.6) | 0.64 (0.07–5.63) | 0.69 |
| −/+ | 12 (10.3) | 9 (9.7) | 1.09(0.39–3.04) | 0.87 | 10 (9.5) | 37 (9.9) | 1.00 (0.45–2.22) | 1.00 |
Note: PM+ = Placental malaria present, PM− = Placental malaria absent. OR = Odds ratio, CI = Confidence interval. P-values are derived from multivariable logistic regression, controlling for gravidity, anti-malarial use during third trimester, and malaria transmission season. Due to missing covariates in models, 115 PM+ and 93 PM− used for HIV-1 negative; 104 PM+ and 372 PM− used for HIV-1 positive. False Discovery Rate (FDR) was used to correct P-values.
‘*’ signifies uncorrected P-value that is <0.05 but is non-significant after correction.
signifies uncorrected P-value that is significant after correction.
Derived using exact logistic regression, median unbiased estimate reported.
Reference group was selected based on the group with highest frequency.
For HIV-1+ women, 373 women were PM−.