Table 2.
Radial and Tibial Bone Variables at the Trabecular and Cortical Sites
| Ad36+a | Ad36−a | ||||
|---|---|---|---|---|---|
|
|
|
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| Bone variable | Normal-fat | High-fat | Normal-fat | High-fat | Virus × adiposity (p)b |
| Radius | |||||
| Trabecular (4%) site | |||||
| Total area (mm2) | 280 ± 6.02 | 246 ± 11.4c | 267 ± 6.25 | 296 ± 14.9 | 0.003 |
| Total BMC (mg/mm) | 95.9 ± 1.85 | 86.8 ± 3.48 | 92.6 ± 1.91 | 97.3 ± 4.56 | 0.032 |
| Total vBMD (mg/cm3) | 348 ± 8.00 | 358 ± 15.1 | 350 ± 8.29 | 332 ± 19.7 | 0.306 |
| Trabecular vBMD (mg/cm3) | 214 ± 4.46 | 207 ± 8.41 | 214 ± 4.62 | 206 ± 11.0 | 0.987 |
| BSI (mg2/mm4) | 3397 ± 120 | 3125 ± 226 | 3267 ± 124 | 3291 ± 296 | 0.475 |
| Cortical (20%) site | |||||
| Total area (mm2) | 97.4 ± 1.65 | 83.7 ± 3.11c | 93.2 ± 1.71 | 99.4 ± 4.07 | 0.001 |
| Cortical BMC (mg/mm) | 83.4 ± 1.07 | 76.1 ± 2.01c | 81.8 ± 1.11 | 84.7 ± 2.64 | 0.006 |
| Cortical vBMD (mg/cm3) | 1191 ± 2.99 | 1196 ± 5.63 | 1196 ± 3.09 | 1185 ± 7.37 | 0.107 |
| Cortical area (mm2) | 70.1 ± .880 | 63.6 ± 1.66c | 68.4 ± .913 | 71.3 ± 2.17 | 0.003 |
| Cortical thickness (mm) | 2.64 ± .031 | 2.67 ± .059 | 2.66 ± .032 | 2.64 ± .077 | 0.707 |
| SSI (mm3) | 225 ± 4.97 | 186 ± 9.37c | 217 ± 5.15 | 235 ± 12.3 | 0.001 |
| Tibia | |||||
| Trabecular (4%) site | |||||
| Total area (mm2) | 938 ± 13.6 | 922 ± 25.4 | 912 ± 14.0 | 939 ± 33.6 | 0.343 |
| Total BMC (mg/mm) | 291 ± 5.26 | 283 ± 9.85 | 290 ± 5.42 | 277 ± 13.0 | 0.743 |
| Total vBMD (mg/cm3) | 311 ± 5.49 | 312 ± 10.3 | 320 ± 5.66 | 293 ± 13.6 | 0.138 |
| Trabecular vBMD (mg/cm3) | 252 ± 3.70 | 250 ± 6.93 | 260 ± 3.82 | 245 ± 9.16 | 0.309 |
| BSI (mg2/mm4) | 9165 ± 303 | 8973 ± 567 | 9358 ± 312 | 8174 ± 749 | 0.334 |
| Cortical (20%) site | |||||
| Total area (mm2) | 342 ± 5.69 | 314 ± 10.7 | 330 ± 5.86 | 326 ± 14.1 | 0.218 |
| Cortical BMC (mg/mm) | 228 ± 3.28 | 213 ± 6.15 | 224 ± 3.38 | 216 ± 8.12 | 0.589 |
| Cortical vBMD (mg/cm3) | 1173 ± 2.34 | 1177 ± 4.41 | 1172 ± 2.43 | 1179 ± 5.83 | 0.699 |
| Cortical area (mm2) | 194 ± 2.72 | 181 ± 5.09 | 191 ± 2.80 | 183 ± 6.72 | 0.615 |
| Cortical thickness (mm) | 3.61 ± .065 | 3.54 ± .121 | 3.61 ± .067 | 3.46 ± .160 | 0.750 |
| SSI (mm3) | 1315 ± 28.4 | 1166 ± 53.2 | 1257 ± 29.3 | 1227 ± 70.3 | 0.221 |
Values are adjusted means ± SEM for muscle cross sectional area (mm2) and limb (radial or tibial) length (mm).
Ad36 = adenovirus 36; Area = cross-sectional area of bone; BMC = bone mineral content; vBMD = volumetric bone mineral density; BSI = bone strength index; BMC = cortical bone mineral content; SSI = strength strain index; OD = optical density.
Cut points used to denote normal-fat and high-fat were determined using cardiovascular risk factors.(14,15) Cut points used to denote Ad36+ and Ad36− were determined by ELISA and were based on control OD values; normal-fat (n=93): Ad36+ (n=48), Ad36− (n=45); high-fat (n=22): Ad36+ (n=14), Ad36− (n=8).
Two × two (virus presence × adiposity) analysis of covariance results for radial and tibial bone variables, adjusting for muscle cross-sectional area and limb length.
Post hoc comparisons show significantly lower bone strength values in Ad36+ versus Ad36− subjects in the high-fat group, but not the normal-fat group.