Table 1.
Characteristics of MrOS Lead Study Participants, across Blood Lead Quartiles
| Characteristics Mean ± sd, or n (%) | N=445 | Overall | Blood Lead Concentration (μg/dl) Quartiles |
P-value | |||
|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | ||||
| (≤1) N=126 | (>1,≤2) N=175 | (>2,≤3) N=84 | (>3) N=60 | ||||
| Age (years) | 445 | 79.5±4.9 | 78.9 | 79.1 | 79.5 | 81.5 | .004 |
| Education College or greater vs. high school | 445 | 214 (48) | 66 (52) | 86 (49) | 39 (46) | 23 (38) | .336 |
| Body mass index (kg/m2) | 445 | 28.2±4.2 | 28.8 | 28.0 | 28.5 | 27.9 | .657 |
| Current smoking (yes/no) | 445 | 11 (2.5) | 0 (0) | 7 (4) | 3 (3.6) | 1 (1.7) | .140 |
| Alcohol (average no of dr /wk)* | 444 | 0.23 (4.3) | 0 (2) | 0.69(5.0) | 0.23(7) | 0.23(7) | .015† |
| BMD (g/cm2)‡ | |||||||
| Femoral neck | 438 | 0.78±0.13 | 0.78 | 0.80 | 0.76 | 0.73 | .001 |
| Total hip | 438 | 0.95±0.15 | 0.96 | 0.98 | 0.92 | 0.91 | .004 |
| Lumbar Spine | 434 | 1.31±0.32 | 1.27 | 1.35 | 1.28 | 1.31 | .183 |
| Physical Function | |||||||
| Grip strength (kg) | 432 | 34.8±8.2 | 35.4 | 35.9 | 33.9 | 31.8 | .006 |
| Leg extension power (watts) | 329 | 164.9±53 | 166.4 | 169.7 | 159.7 | 154.0 | .313 |
| Walk speed (m/s) | 435 | 1.02±0.23 | 1.05 | 1.04 | 0.99 | 0.98 | .087 |
| Narrow walk (m/s) | 302 | 1.09±0.24 | 1.08 | 1.12 | 1.07 | 1.04 | .258 |
| Use arms to stand up (yes/no) | 445 | 59 (13) | 19 (15) | 17 (10) | 13 (15) | 10 (17) | .350 |
| Cognitive function | |||||||
| Trails B test score (0-300 sec)§ | 414 | 123.2±57 | 120.7 | 120.8 | 122.8 | 130.0 | .330 |
| Teng score 3MS (0 to 100) | 442 | 92.3±0.0 | 92.5 | 92.7 | 92.3 | 90.7 | .247 |
*
Median (interquartile range)
†
Wilcoxon non-parametric test
‡
Bone Mineral Density
§
An increase in this performance measure indicates a decline in cognitive function