Background
Methods
Study site and population
Study sample and definition of terms
Characteristic | Exposed (N = 58) | Unexposed (N = 56) | Comparison |
---|---|---|---|
Median age in years (IQR) | 6.0 (6.0-7.0) | 6.0 (6.0-8.0) | Z = -1.72, P = 0.085 |
Male sex (%) | 27 (46.6) | 27 (48.2) | X2 = 0.03, P = 0.859 |
Home delivery (%) | 43 (81.1) | 48/54 (88.9) | X2 = 1.27, P = 0.261 |
Perinatal problems (%) | 15 (25.8) | 11 (19.1) | X = 0.63, P = 0.429 |
Incomplete immunization (%) | 40/41 (97.6) | 35/36 (97.2) | P = 1.00a |
Median maternal age in years (IQR) | 34.0 (29.0-44.0) | 32.0 (27.5-37.5) | Z = -0.86, P = 0.390 |
Mother did not attend school (%) | 29/52 (54.7) | 28/53 (53.9) | X2 = 0.01, P = 0.929 |
Unschooled dad (%) | 14/51 (27.5) | 11/49 (22.5) | X2 = 0.33, P = 0.564 |
Lack of maternal economic activity (%) | 19/51 (37.3) | 24/51 (47.1) | X2 = 1.01, P = 0.316 |
Lack of paternal economic activity (%) | 12/48 (25.0) | 12/46 (26.1) | X2 = 0.02, P = 0.904 |
Child attends school (%) | 39 (67.2) | 40 (71.4) | X2 = 0.33, P = 0.564 |
Median number of previous hospitalization, IQR (%) | 2 (1–3) | 2 (1–3) | Z = 1.70, P = 0.088 |
History of seizures (%) | 6/54 (11.1) | 7/53 (13.2) | X2 = 0.11, P = 0.740 |
Assessment of neurocognition
Assessment procedure
Self-ordered pointing test (SOPT)
Contingency naming test (CNT)
Score/ test for everyday attention test for children (TEA-Ch)
Computerized visual search task (Vigilance)
Statistical analysis
Results
Comparison between combined exposed group and controls
Description | Cases | Controls | Comparisona | Comparisonb | |||
---|---|---|---|---|---|---|---|
Cerebral malaria | Malarial seizures | Malarial prostration | Malarial seizures with fever | Unexposed | |||
Vigilance test
| |||||||
Omissionc | 0.63 (0.45-0.71) | 0.46 (0.32-0.66) | 0.66 (0.64-0.86) | 0.71 (0.47-0.87 | 0.64 (0.50-0.75 | X2 = 6.08, P = 0.108 | Z = 1.13, P = 0.259 |
Commissionc | 0.40 (0.28-0.50) | 0.60 (0.37-0.78) | 0.37 (0.32-0.46) | 0.53 (0.30-0.63) | 0.35 (0.18-0.49) | X2 = 7.10, P = 0.069 | Z = -1.22, P = 0.222 |
Average time | 11.5 (10.9- 12.5) | 9.6 (7.7-11.9) | 11.6 (10.7-11.9) | 11.2 (9.9-11.7) | 11.6 (10.6-12.4) | X2 = 8.351, P = 0.039 | Z = 0.50, P = 0.616 |
Efficiency | 5.6 (5.1-6.1) | 4.9 (2.3-5.7) | 5.9 (5.5-6.3) | 4.7 (4.3-5.5) | 5.9 (4.8-6.8) | X2 = 6.265, P = 0.099 | Z = 0.93, P = 0.351 |
Test of everyday attention for children (TEA-Ch) test
| |||||||
Median test total (IQR) | 5.0 (4.0-9.0) | 3.5 (3.0-7.0) | 7.0 (5.0-9.0) | 4.0 (2.5-5.0) | 7.0 (4.0-10.0) | X2 = 4.62, P = 0.198 | Z = 0.46, P = 0.644 |
Contingency Naming Test (CNT)
| |||||||
Median total error1 (IQR) | 0 (0–2.0) | 0 (0–2.0) | 0 (0–1.0) | 0 (0–0.5) | 0 (0–2.0) | X2 = 1.57, P = 0.667 | Z = 1.03, P = 0.303 |
Median efficiency1 (IQR) | 1.5 (0.8-1.9) | 1.0 (0.7-1.4) | 1.3 (1.2-1.9) | 1.4 (1.2-1.7) | 1.3 (0.8-1.8) | X2 = 3.70, P = 0.295 | Z = -1.08, P = 0.279 |
Median total error2 (IQR) | 1.0 (0–4.0) | 2.0 (0–6.0) | 1.0 (0–3.0) | 0 (0.9.5) | 1.0 (0–3.5) | X2 = 1.27, P = 0.735 | Z = 0.20, P = 844 |
Median efficiency2 (IQR) | 0.5 (0.2-0.7) | 0.3 (0.1-0.6) | 0.5 (0.4-0.7) | 0.7 (0.4-0.8) | 0.5 (0.2-0.8) | X2 = 2.86, P = 0.413 | Z = -0.61, P = 0.539 |
Median total error3 (IQR) | 12.0 (9.0-15) | 13 (9.0-16.0) | 11.0 (10.0-16.0) | 13.5 (10.0-17.0) | 12.0 (9.0-15.0) | X2 = 0.35, P = 0.950 | Z = -0.09, P = 0.927 |
Median efficiency3 (IQR) | 0.09 (0.07-0.14) | 0.10 (0.06-0.12) | 0.11 (0.09-0.12) | 0.09 (0.07-0.15) | 0.10 (0.07-0.13) | X2 = 1.33, P = 0.721 | Z = -0.68, P = 0.499 |
Median total error4 (IQR) | 14.0 (12.0-15.0) | 14.0 (12.0-16.0) | 14.0 (12.0-15.0) | 15.5 (13.5-17.0) | 13.0 (12.0-15.0) | X2 = 1.45, P = 0.694 | Z = -0.62, P = 0.534 |
Median efficiency4 (IQR) | 0.05 (0.04-0.07) | 0.04 (0.03-0.06) | 0.05 (0.04-0.06) | 0.05 (0.04-0.06) | 0.05 (0.04-0.06) | X2 = 1.05, P = 0.790 | Z = -0.75, P = 0.456 |
Self-ordered pointing test (SOPT)
| |||||||
Total errors | 23.0 (19.0-31.0) | 32.0 (22.0-35.0) | 26.0 (25.0-29.0) | 28.0 (24.0-36.0) | 24.0 (18.0-29.0) | X2 = 3.86, P = 0.277 | t = -1.44, P = 0.152 |
Comparison between specific neurological phenotypes of severe malaria and controls
Phenotypes of severe malaria | Vigilance efficiency scores, β (95% CI) | TEA-Ch test total scores, β (95% CI) | Contingency naming test average total error scores, β (95% CI) | Contingency naming test average efficiency scores, β (95% CI) | Self-ordered pointing test, β (95% CI) |
---|---|---|---|---|---|
Impaired consciousness: unadjusted model | 0.02 (-0.12-0.18); P = 0.734 | 0.09 (-0.33-0.51); P = 0.667 | -0.07 (-0.28-0.14); P = 0.494 | 0.07 (-0.02-0.16); P = 0.110 | 0.47 (-2.73-3.67); P = 0.771 |
Impaired consciousness: adjusted model | 0.03 (-0.14-0.20); P = 0.756 | -0.40 (-0.81-0.01); P = 0.058 | 0.08 (-0.35-0.19); P = 0.542 | 0.06 (-0.06-0.18); P = 0.329 | 0.99 (-3.12-5.11); P = 0.628 |
Complex seizures: unadjusted model | -0.35 (-0.59--0.10); P = 0.006 | -0.27 (-0.81-0.27); P = 0.318 | -0.04 (-0.36-0.28); P = 0.808 | -0.01 (-0.12-0.12); P = 0.919 | 4.70 (0.50-8.90); P = 0.029 |
Complex seizures: adjusted model | -0.47 (-0.67--0.13); P = 0.006 | -0.57 (-1.04--0.10); P = 0.019 | -0.59 (-0.20-0.08); P = 0.411 | 0.10 (-0.32-0.52); P = 0.629 | 4.57 (-0.73-9.89); P = 0.089 |
Seizures with fever: unadjusted model | -0.16 (-0.53-0.21);P = 0.377 | -0.44 (-1.40-0.52); P = 0.361 | 0.07 (-0.46-0.60); P = 0.802 | 0.09 (-0.10-0.27); P = 0.342 | 5.20 (-1.64-12.05); P = 0.133 |
Seizures with fever: adjusted model | -0.06 (-0.50-0.37); P = 0.763 | -0.42 (-1.34-0.50); P = 0.352 | 0.18 (-0.62-0.98); P = 0.647 | 0.04 (-0.21-0.29); P = 0.746 | 2.72 (-6.07-2.59); P = 0.529 |
Prostration: unadjusted model | -0.00 (-0.25-0.25); P = 0.994 | 0.33 (-0.35-1.01); P = 0.339 | -0.05 (-0.42-0.33); P = 0.800 | 0.10 (-0.03-0.22); P = 0.142 | 1.31 (-3.19-5.82); P = 0.562 |
Prostration: adjusted model | -0.01 (-0.26-0.25); P = 0.963 | 0.21 (-0.38-0.81); P = 0.474 | -0.11 (-0.62-0.39); P = 0.653 | 0.10 (-0.06-0.25); P = 0.205 | 1.59 (-3.86-7.05); P = 0.555 |
All phenotypes: unadjusted model | -0.08 (-0.23-0.05); P = 0.219 | 0.01 (-0.34-0.34); P = 0.989 | -0.05 (-0.23-0.12); P = 0.575 | 0.06 (-0.01-0.13); P = 0.090 | 1.98 (-0.74-4.69); P = 0.152 |
All phenotypes: adjusted model | -0.13 (-0.13-0.04); P = 0.137 | -0.29 (-0.66-0.07); P = 0.109 | -0.03 (-0.26-0.20); P = 0.800 | 0.04 (-0.05-0.13); P = 0.408 | 2.00 (-1.28-5.29); P = 0.229 |