Table 2a.
Mean and standard deviation (SD) for pQCT-derived outcomes at 60-64 years by age at menarche, women
| Age at menarche |
|||||||||
|---|---|---|---|---|---|---|---|---|---|
| 9-10 | 11 | 12 | 13 | 14 | 15-19 | Totalsample | P-value * | ||
| No. | Mean (SD) | Mean (SD) | Mean (SD) | Mean (SD) | Mean (SD) | Mean (SD) | Mean (SD) | ||
| pQCT | |||||||||
| Distal CSA mm2 (4%) | 566 | 132 (23) | 132 (24) | 130 (24) | 134 (25) | 136 (24) | 129 (24) | 133 (24) | 0.3 |
| Diaphysis CSA mm2 (50%) | 571 | 111 (12) | 113 (17) | 115 (17) | 111 (16) | 112 (14) | 112 (18) | 113 (16) | 0.3 |
| Medullary CSA mm2 (50%) | 570 | 31 (9) | 34 (13) | 37 (13) | 36 (12) | 35 (12) | 35 (13) | 35 (12) | 0.7 |
| Polar SSI mm3 (50%) | 572 | 212 (34) | 217 (45) | 214 (45) | 207 (42) | 208 (39) | 211 (39) | 211 (43) | 0.1 |
| Total vBMD mg/cm3 (4%) | 566 | 351 (82) | 339 (69) | 340 (74) | 322 (70) | 318 (64) | 337 (69) | 332 (71) | 0.01 |
| Trabecular vBMD mg/cm3 (4%) | 565 | 178 (40) | 177 (41) | 179 (46) | 169 (41) | 168 (35) | 158 (40) | 173 (42) | 0.004 |
| Cortical vBMD mg/cm3 (50%) | 572 | 1157 (33) | 1146 (44) | 1146 (40) | 1149 (40) | 1152 (33) | 1151 (40) | 1148 (39) | 0.5 |
| DXA | |||||||||
| Lumbar spine aBMD g/cm2 | 699 | 0.98 (0.14) | 0.98 (0.18) | 0.95 (0.16) | 0.95 (0.16) | 0.92 (0.15) | 0.91 (0.16) | 0.95 (0.16) | 0.006 |
| Total hip aBMD g/cm2 | 695 | 0.90 (0.14) | 0.90 (0.13) | 0.87 (0.12) | 0.86 (0.13) | 0.85 (0.12) | 0.84 (0.12) | 0.87 (0.13) | 0.001 |
*P-values from regression models with logged bone outcomes and including age at menarche in months since birth as a continuous variable.