| Characteristic | Tenwek, N = 1,6541 | UW African American, N = 1,6521 | UW white American, N = 16,5401 | MGB African American, N = 1,6541 | MGB white American, N = 16,5401 | p-value2 |
|---|---|---|---|---|---|---|
| Patient Age | 54 (18) | 54 (18) | 54 (18) | 54 (18) | 54 (18) | >0.9 |
| Patient Sex | 0.2 | |||||
| F | 768 (46%) | 816 (49%) | 7,680 (46%) | 757 (46%) | 7,750 (47%) | |
| M | 886 (54%) | 836 (51%) | 8,860 (54%) | 897 (54%) | 8,790 (53%) | |
| IVContrast_IVContrastPresent | 1,439 (87%) | 1,068 (65%) | 10,343 (63%) | 1,234 (75%) | 12,848 (78%) | <0.001 |
| ContrastCorrected_FatValues_L3VATArea | 64 (69) | 137 (114) | 175 (134) | 127 (103) | 159 (128) | <0.001 |
| ContrastCorrected_FatValues_L3SATArea | 97 (107) | 241 (164) | 221 (132) | 227 (151) | 216 (129) | <0.001 |
| ContrastCorrected_FatValues_L3TATArea | 162 (165) | 382 (241) | 399 (227) | 357 (219) | 378 (218) | <0.001 |
| ContrastCorrected_FatValues_L3VATSATRatio | 0.99 (1.16) | 0.65 (0.50) | 0.87 (0.70) | 0.65 (0.53) | 0.80 (0.93) | <0.001 |
| ContrastCorrected_FatValues_L3VATMedian | -99 (27) | -89 (15) | -90 (12) | -90 (14) | -91 (13) | <0.001 |
| ContrastCorrected_MuscleValues_L3MuscleArea | 117 (31) | 161 (44) | 157 (42) | 157 (41) | 153 (41) | <0.001 |
| ContrastCorrected_MuscleValues_L3MuscleMeanHU | 31 (14) | 34 (18) | 30 (18) | 29 (18) | 28 (18) | <0.001 |
| ContrastCorrected_BMDValues_BMDStandardHU | 173 (64) | 184 (52) | 164 (50) | 187 (54) | 165 (53) | <0.001 |
| ContrastCorrected_CalciumScoring_AbdominalAgatston | 330 (1,459) | 904 (2,574) | 1,335 (3,416) | 660 (2,331) | 1,156 (3,050) | <0.001 |
| ContrastCorrected_KidneyValues_KidneyVolume | 247 (74) | 391 (132) | 403 (135) | 389 (129) | 410 (125) | <0.001 |
| ContrastCorrected_SpleenValues_SpleenVolume | 185 (172) | 173 (139) | 404 (3,535) | 198 (1,181) | 411 (3,679) | <0.001 |
| ContrastCorrected_LiverValues_LiverHU | 48 (10) | 54 (19) | 53 (20) | 52 (10) | 51 (11) | <0.001 |
| ContrastCorrected_LiverValues_LiverVolume | 1,177 (561) | 1,498 (634) | 1,591 (711) | 1,516 (703) | 1,612 (723) | <0.001 |
| L1 trabecular bone attenuation (HU) | 173 (64) | 184 (52) | 163 (48) | 187 (54) | 165 (49) | <0.001 |
| Abdominal aortic Agatston score | 330 (1,459) | 904 (2,574) | 1,335 (3,416) | 660 (2,331) | 1,156 (3,050) | <0.001 |
| L3 skeletal muscle attenuation (HU) | 31 (14) | 33 (17) | 30 (17) | 29 (18) | 28 (18) | <0.001 |
| L3 skeletal muscle area (cm2) | 117 (31) | 161 (43) | 157 (42) | 157 (40) | 153 (40) | <0.001 |
| Liver attenuation (HU) | 48 (10) | 53 (9) | 51 (11) | 52 (10) | 51 (11) | <0.001 |
| Liver volume (ml) | 1,177 (549) | 1,538 (590) | 1,639 (658) | 1,489 (601) | 1,591 (628) | <0.001 |
| Spleen attenuation (HU) | 90 (27) | 85 (36) | 83 (34) | 88 (35) | 92 (34) | <0.001 |
| Spleen volume (ml) | 187 (172) | 175 (139) | 261 (184) | 170 (130) | 258 (186) | <0.001 |
| L3 TAT area (cm2) | 166 (165) | 380 (237) | 399 (226) | 357 (219) | 378 (218) | <0.001 |
| L3 VAT area (cm2) | 45 (91) | 137 (109) | 175 (134) | 127 (103) | 159 (128) | <0.001 |
| L3 SAT area (cm2) | 97 (107) | 241 (162) | 221 (132) | 227 (151) | 216 (129) | <0.001 |
| L3 VAT attenuation (HU) | -94 (13) | -88 (10) | -90 (10) | -88 (10) | -90 (10) | <0.001 |
| VAT to SAT Ratio | 1.02 (1.17) | 0.65 (0.50) | 0.86 (0.68) | 0.65 (0.53) | 0.79 (0.66) | <0.001 |
| Kidney attenuation (HU) | 109 (40) | 100 (57) | 95 (56) | 108 (54) | 108 (50) | <0.001 |
| Kidney volume (ml) | 249 (68) | 392 (113) | 401 (114) | 388 (115) | 406 (110) | <0.001 |
| 1 Mean (SD); n (%) | ||||||
| 2 Kruskal-Wallis rank sum test; Pearson’s Chi-squared test | ||||||
Abdominal CT Opportunistic Screening: Comparison of body composition measures between a Kenyan patient cohort and a matched UW cohort using artificial intelligence tools
Statistical analysis
Categorical variables were summarized using counts and percentages, while continuous variables were summarized using means and standard deviations. The differences between cohorts were assessed using the Cho-squared test for categorical variables and the Kruskal-Wallis rank sum test for continuous variables. All analyses were performed using R version 4.2.2 (R Core Team, 2022).
Results
Tables
Comparisons of demographics and body composition measures between the cohorts are shown in the tables below.
| Characteristic | Tenwek, N = 1,6541 | US African American, N = 3,3061 | US White American, N = 33,0801 | p-value2 |
|---|---|---|---|---|
| Patient Age | 54 (18) | 54 (18) | 54 (18) | 0.8 |
| Patient Sex | 0.6 | |||
| F | 768 (46%) | 1,573 (48%) | 15,430 (47%) | |
| M | 886 (54%) | 1,733 (52%) | 17,650 (53%) | |
| IVContrast_IVContrastPresent | 1,439 (87%) | 2,302 (70%) | 23,191 (70%) | <0.001 |
| ContrastCorrected_FatValues_L3VATArea | 64 (69) | 132 (109) | 167 (131) | <0.001 |
| ContrastCorrected_FatValues_L3SATArea | 97 (107) | 234 (158) | 219 (131) | <0.001 |
| ContrastCorrected_FatValues_L3TATArea | 162 (165) | 369 (231) | 388 (223) | <0.001 |
| ContrastCorrected_FatValues_L3VATSATRatio | 0.99 (1.16) | 0.65 (0.51) | 0.83 (0.83) | <0.001 |
| ContrastCorrected_FatValues_L3VATMedian | -99 (27) | -89 (14) | -90 (13) | <0.001 |
| ContrastCorrected_MuscleValues_L3MuscleArea | 117 (31) | 159 (42) | 155 (41) | <0.001 |
| ContrastCorrected_MuscleValues_L3MuscleMeanHU | 31 (14) | 31 (18) | 29 (18) | <0.001 |
| ContrastCorrected_BMDValues_BMDStandardHU | 173 (64) | 186 (53) | 164 (51) | <0.001 |
| ContrastCorrected_CalciumScoring_AbdominalAgatston | 330 (1,459) | 780 (2,456) | 1,243 (3,236) | <0.001 |
| ContrastCorrected_KidneyValues_KidneyVolume | 247 (74) | 390 (131) | 406 (130) | <0.001 |
| ContrastCorrected_SpleenValues_SpleenVolume | 185 (172) | 186 (844) | 407 (3,608) | <0.001 |
| ContrastCorrected_LiverValues_LiverHU | 48 (10) | 53 (15) | 52 (16) | <0.001 |
| ContrastCorrected_LiverValues_LiverVolume | 1,177 (561) | 1,507 (669) | 1,601 (717) | <0.001 |
| L1 trabecular bone attenuation (HU) | 173 (64) | 186 (53) | 164 (49) | <0.001 |
| Abdominal aortic Agatston score | 330 (1,459) | 780 (2,456) | 1,243 (3,236) | <0.001 |
| L3 skeletal muscle attenuation (HU) | 31 (14) | 31 (18) | 29 (18) | <0.001 |
| L3 skeletal muscle area (cm2) | 117 (31) | 159 (42) | 155 (41) | <0.001 |
| Liver attenuation (HU) | 48 (10) | 52 (10) | 51 (11) | <0.001 |
| Liver volume (ml) | 1,177 (549) | 1,513 (596) | 1,615 (644) | <0.001 |
| Spleen attenuation (HU) | 90 (27) | 86 (35) | 88 (34) | 0.070 |
| Spleen volume (ml) | 187 (172) | 172 (134) | 260 (185) | <0.001 |
| L3 TAT area (cm2) | 166 (165) | 369 (228) | 388 (222) | <0.001 |
| L3 VAT area (cm2) | 45 (91) | 132 (106) | 167 (131) | <0.001 |
| L3 SAT area (cm2) | 97 (107) | 234 (157) | 219 (131) | <0.001 |
| L3 VAT attenuation (HU) | -94 (13) | -88 (10) | -90 (10) | <0.001 |
| VAT to SAT Ratio | 1.02 (1.17) | 0.65 (0.51) | 0.83 (0.67) | <0.001 |
| Kidney attenuation (HU) | 109 (40) | 104 (55) | 102 (53) | 0.002 |
| Kidney volume (ml) | 249 (68) | 390 (114) | 403 (112) | <0.001 |
| 1 Mean (SD); n (%) | ||||
| 2 Kruskal-Wallis rank sum test; Pearson’s Chi-squared test | ||||
Figures
Boxplots for the variables of interest are shown below (outliers are suppressed).
