Table 1. Demographic and Clinical Characteristics Prior to Surgery.
| Full Analysis Sample (N = 1406) |
Weight Regain Subsample (n = 1286)a |
|
|---|---|---|
| Age, median (25th-75th percentile), y | 47 (38-55) | 46 (38-55) |
| Female, No. (%) | 1129 (80.3) | 1030 (80.1) |
| Race, No./total No. (%) | ||
| White | 1193/1394 (85.6) | 1092/1276 (85.6) |
| Black | 150/1394 (10.8) | 137/1276 (10.7) |
| Asian | 3/1394 (0.2) | 3/1276 (0.2) |
| American Indian/Alaskan Native | 14/1394 (1.0) | 13/1276 (1.0) |
| Native Hawaiian/other Pacific Islander | 3/1394 (0.2) | 3/1276 (0.2) |
| Mixed (≥2 races) | 31/1394 (2.2) | 28/1276 (2.2) |
| Hispanic or Latino ethnicity, No. (%) | 61 (4.3) | 58 (4.5) |
| Married or living as married, No. (%) | 818 (58.2) | 751 (58.4) |
| Education, No./total No. (%) | ||
| ≤High school degree | 305/1307 (23.3) | 277/1196 (23.2) |
| Some college | 559/1307 (42.8) | 517/1196 (43.2) |
| College degree | 443/1307 (33.9) | 402/1196 (33.6) |
| Unemployed, No. (%) | 50 (3.6) | 46 (3.6) |
| Household income, No./total No. (%) | ||
| <$25 000 | 243/1271 (19.1) | 212/1166 (18.2) |
| $25 000-$49 999 | 358/1271 (28.2) | 333/1166 (28.6) |
| $50 000-$74 999 | 300/1271 (23.6) | 277/1166 (23.8) |
| $75 000-$99 999 | 194/1271 (15.3) | 181/1166 (15.5) |
| ≥$100 000 | 176/1271 (13.8) | 163/1166 (14.0) |
| Current or recent smoker, No./total No. (%) | 183/1404 (13.0) | 156/1284 (12.1) |
| Weight, median (25th-75th percentile), kg | 129.7 (116.1-148.8) | 129.3 (116.1-147.4) |
| Body mass index, median (25th-75th percentile)b | 46.3 (42.3-51.8) | 46.2 (42.2-51.7) |
| Diabetes, No./total No. (%) | 502/1383 (36.3) | 438/1221 (35.9) |
| Hyperlipidemia, No./total No. (%) | 525/1219 (43.1) | 399/1035 (38.6) |
| Hypertension, No./total No. (%) | 972/1383 (70.3) | 869/1244 (69.9) |
| SF-36 score, median (25th-75th percentile)c | ||
| Physical Component Summary | 35.1 (26.7-43.9) | 35.3 (27.0-44.2) |
| Mental Component Summary | 51.6 (42.8-57.2) | 52.0 (43.4-57.4) |
Abbreviation: SF-36, 36-item Short-Form Health Survey.
a
The subsample size is 1286 because 120 patients were excluded from the evaluation of weight regain (119 reached nadir weight during the final year of data collection; 1 was pregnant at the only assessment after reaching nadir weight).
b
Calculated as weight in kilograms divided by height in meters squared.
c
Lower scores imply more disability or worse function. There were missing data for 119 patients in the full analysis sample and 103 patients in the subsample for this variable. Norm-based methods transform the score to a mean (SD) of 50 (10) in the general US population (range, 0-100).