Table 4.
Association, Discrimination and Reclassification for FNIH Alternative Sarcopenia Definitions with Falls, Functional Limitation, Hip Fractures and Mortality in Older Men
| Recurrent falls | FNIH Alternative Sarcopenia Classification | |
|---|---|---|
| Definition #1 | Definition #2 | |
| Association and discrimination | ||
| OR (95% CI) in model with age alone | 2.33 (1.32, 4.10) | 2.37 (0.79, 7.07) |
| Change in AUC (95% CI) compared to model with age alone | 0.003 (−0.001, 0.007) | 0.000 (−0.001, 0.001) |
| Reclassification | ||
| Among those with event (N=694)a | ||
| Appropriately reclassified | 18 (3%) | 5 (1%) |
| Inappropriately reclassified | 105 (15%) | 40 (6%) |
| No change | 571 (82%) | 649 (94%) |
| NRI c (95%CI), events | −0.13 (−0.16, −0.10) | −0.05 (−0.07, −0.03) |
| Among those without event (N=5134)b | ||
| Appropriately reclassified | 433 (8%) | 159 (3%) |
| Inappropriately reclassified | 45 (1%) | 11 (0%) |
| No change | 4656 (91%) | 4964 (97%) |
| NRI (95%CI), non-events | 0.08 (0.07, 0.08) | 0.03 (0.02, 0.03) |
| Overall NRI (95% CI) | −0.05 (−0.08, −0.02) | −0.02 (−0.04, 0.00) |
|
| ||
| Hip Fractures | ||
| Association and discrimination | ||
| HR (95% CI) in model with age + BMD | 1.68 (0.74, 3.81) | 5.46 (1.71, 17.46) |
| Change in C-statistic (95% CI) compared to model with age + BMD | −0.001 (−0.001, 0.000) | 0.000 (−0.001, 0.000) |
| Reclassification | ||
| Among those with event (N=207)a | ||
| Appropriately reclassified | 6 (3%) | 3 (1%) |
| Inappropriately reclassified | 11 (5%) | 17 (8%) |
| No change | 190 (92%) | 187 (90%) |
| NRI c (95%CI), events | −0.02 (−0.06, 0.01) | −0.07 (−0.11, −0.03) |
| Among those without event (N=5727)b | ||
| Appropriately reclassified | 185 (3%) | 213 (4%) |
| Inappropriately reclassified | 60 (1%) | 53 (1%) |
| No change | 5482 (96%) | 5461 (95%) |
| NRI (95%CI), non-events | 0.02 (0.02, 0.03) | 0.03 (0.02,0.03) |
| Overall NRI (95% CI) | 0.00 (−0.04, 0.04) | −0.04 (−0.08, 0.00) |
|
| ||
| Functional Limitations | ||
| Association and discrimination | ||
| OR (95% CI) in model with age alone | 1.01 (0.81, 1.23) | 1.30 (1.04, 1.65) |
| Change in AUC (95% CI) compared to model with age alone | 0.000 (−0.001, 0.001) | 0.001 (−0.005, 0.007) |
| Reclassification | ||
| Among those with event (N=590)a | ||
| Appropriately reclassified | 38 (6%) | 133 (23%) |
| Inappropriately reclassified | 0 (0%) | 236 (40%) |
| No change | 552 (94%) | 221 (37%) |
| NRI c (95%CI), events | 0.06 (0.04, 0.08) | −0.17 (−0.24, −0.11) |
| Among those without event (N=3136)b | ||
| Appropriately reclassified | 1 (0%) | 982 (31%) |
| Inappropriately reclassified | 147 (5%) | 495 (16%) |
| No change | 2988 (95%) | 1659 (53%) |
| NRI (95%CI), non-events | −0.05 (−0.05, −0.04) | 0.16 (0.13, 0.18) |
| Overall NRI (95% CI) | 0.02 (0.00, 0.04) | −0.02 (−0.09, 0.05) |
|
| ||
| Mortality | ||
| Association and discrimination | ||
| HR (95% CI) in model with age alone | 2.03 (1.51, 2.73) | 3.49 (2.01, 6.05) |
| Change in C-statistic (95% CI) compared to model with age and BMD | 0.002 (0.001, 0.003) | 0.001 (0.000, 0.002) |
| Reclassification | ||
| Among those with event (N=2003)a | ||
| Appropriately reclassified | 52 (3%) | 22 (1%) |
| Inappropriately reclassified | 551 (28%) | 306 (15%) |
| No change | 1400 (70%) | 1675 (84%) |
| NRI c (95%CI), events | −0.25 (−0.27, −0.23) | −0.14 (−0.16, −0.13) |
| Among those without event (N=3866)b | ||
| Appropriately reclassified | 641 (17%) | 222 (6%) |
| Inappropriately reclassified | 123 (3%) | 130 (3%) |
| No change | 3102 (80%) | 3514 (91%) |
| NRI (95%CI), non-events | 0.13 (0.12, 0.15) | 0.02 (0.01, 0.03) |
| Overall NRI (95% CI) | −0.12 (−0.14, −0.09) | −0.12 (−0.14, −0.10) |
Bold text indicates p<0.05.
For recurrent falls, AUC for model with age alone was 0.577.
For hip fractures, C-statistic for model with age and BMD was 806.
For functional limitations, AUC for model with age alone was 0.632
For mortality, C-statistic for model with age alone was 0.684.
FNIH alternative definition #1: Presence of both weakness (grip<26 kg) and low lean mass (ALM<19.75 kg)
FNIH alternative definition #2: Presence of slowness (gait≤0.8 m/s), weakness (grip<26 kg) and low lean mass (ALM<19.75 kg)
FNIH = Foundation for NIH Sarcopenia Project, ALM=appendicular lean mass, AUC=area under the curve, BMD=bone mineral density, NRI = net reclassification improvement
For events, appropriate reclassification occurs when estimated risk increases when the additional factor is added to the model; inappropriate reclassification occurs when estimated risk decreases when the additional factor is added to the model.
For non-events, appropriate reclassification occurs when estimated risk decreases when the additional factor is added to the model; inappropriate reclassification occurs when estimated risk increases when the additional factor is added to the model.