Table 1.
Baseline characteristics by physical activity categories
| Mean (±SD) or n (%) | Physical Activity in MET-minutes/week |
||||
|---|---|---|---|---|---|
| 0 (n=489) |
1–499 (n=1458) |
500–999 (n=1086) |
≥1000 (n=2470) |
P value for linear trend |
|
| Age, years | 75 (±6) | 74 (±6) | 73 (±5) | 73 (±5) | <0.001 |
| Female | 316 (65%) | 877 (60%) | 612 (56%) | 1375 (56%) | <0.001 |
| African American | 103 (21%) | 358 (25%) | 154 (14%) | 225 (9%) | <0.001 |
| Education higher than high school | 186 (38%) | 577 (40%) | 475 (44%) | 1130 (46%) | <0.001 |
| Income >25K | 157 (32%) | 477 (33%) | 401 (37%) | 1012 (41%) | <0.001 |
| Alcohol, drinks per week | 2.0 (±6.5) | 2.3 (±6.6) | 2.6 (±6.6) | 2.6 (±6.2) | 0.134 |
| Smoke, pack-years | 19 (±31) | 18 (±26) | 18 (±27) | 17 (±26) | 0.277 |
| Never eat chicken skin | 325 (67%) | 942 (65%) | 733 (68%) | 1799 (73%) | <0.001 |
| Body mass index, kg/m2 | 27 (±4) | 28 (±4) | 27 (±4) | 26 (±4) | <0.001 |
| Systolic blood pressure, mmHg | 140 (±23) | 138 (±22) | 136 (±21) | 135 (±21) | <0.001 |
| Diastolic blood pressure, mmHg | 72 (±12) | 72 (±11) | 71 (±11) | 70 (±11) | <0.001 |
| Medical problems | |||||
| Coronary heart diseases | 111 (23%) | 272 (19%) | 183 (17%) | 393 (16%) | <0.001 |
| Acute myocardial infarction | 52 (11%) | 122 (8%) | 84 (8%) | 184 (7%) | 0.032 |
| Angina pectoris | 96 (20%) | 231 (16%) | 147 (14%) | 321 (13%) | <0.001 |
| Hypertension | 326 (67%) | 923 (63%) | 636 (59%) | 1330 (54%) | <0.001 |
| Diabetes mellitus | 106 (22%) | 272 (19%) | 165 (15%) | 315 (13%) | <0.001 |
| Stroke | 42 (9%) | 65 (4%) | 35 (3%) | 71 (3%) | <0.001 |
| Atrial fibrillation | 16 (3%) | 36 (2%) | 17 (2%) | 46 (2%) | 0.038 |
| Left ventricular hypertrophy by electrocardiogram | 37 (8%) | 69 (5%) | 42 (4%) | 91 (4%) | 0.001 |
| Left ventricular systolic dysfunction by echocardiogram | 44 (9%) | 111 (8%) | 90 (8%) | 165 (7%) | 0.070 |
| Arthritis | 306 (63%) | 773 (53%) | 548 (51%) | 1228 (50%) | <0.001 |
| Chronic obstructive pulmonary disease | 81 (17%) | 200 (14%) | 140 (13%) | 265 (11%) | <0.001 |
| Cancer | 67 (14%) | 230 (16%) | 161 (15%) | 335 (14%) | 0.208 |
| Geriatric problems | |||||
| Activity of daily living | 0.39 (±0.9) | 0.15 (±0.5) | 0.08 (±0.4) | 0.06 (±0.3) | <0.001 |
| Instrumental activity of daily living | 0.86 (±1.2) | 0.43 (±0.8) | 0.30 (±0.6) | 0.18 (±0.5) | <0.001 |
| Blocks walked last week | 13 (±30) | 20 (±32) | 38 (±46) | 56 (±66) | <0.001 |
| Time to walk 15 ft | 6.9 (±3.1) | 6.1 (±2.4) | 5.7 (±1.8) | 5.4 (±2.0) | <0.001 |
| Mini mental state examination score | 26.8 (±3.4) | 27.3 (±3.0) | 27.8 (±2.4) | 27.8 (±2.4) | <0.001 |
| Depression score | 6.0 (±5.3) | 5.2 (±4.7) | 4.5 (±4.3) | 4.1 (±4.2) | <0.001 |
| Loss of balance | 150 (31%) | 377 (26%) | 237 (22%) | 502 (20%) | <0.001 |
| Frequent fall | 35 (7%) | 54 (4%) | 34 (3%) | 57 (2%) | <0.001 |
| Orthostatic dizziness | 149 (31%) | 317 (22%) | 235 (22%) | 425 (17%) | <0.001 |
| Laboratory measures | |||||
| Serum cholesterol, mg/dL | 219 (±42) | 211 (±40) | 211 (±38) | 212 (±38) | 0.001 |
| Serum triglyceride, mg/dL | 152.7 (±96.4) | 141.3 (±70.8) | 142.0 (±82.5) | 134.7 (±72.8) | <0.001 |
| Serum creatinine, mg/dL | 1.01 (±0.46) | 0.98 (±0.45) | 0.95 (±0.39) | 0.93 (±0.31) | <0.001 |
| Serum potassium, mEq/L | 4.1 (±0.40) | 4.1 (±0.39) | 4.2 (±0.37) | 4.2 (±0.37) | 0.001 |
| Serum glucose, mg/dL | 116 (±42) | 115 (±40) | 111 (±38) | 107 (±32) | <0.001 |
| Serum albumin, g/dL | 4.0 (±0.3) | 4.0 (±0.3) | 4.0 (±0.3) | 4.0 (±0.3) | 0.176 |
| Serum uric acid, mg/dL | 6.0 (±1.7) | 5.8 (±1.5) | 5.7 (±1.5) | 5.5 (±1.4) | <0.001 |
| Serum C-reactive protein, mg/dL | 5.7 (±7.8) | 5.6 (±9.3) | 4.4 (±8.0) | 4.0 (±7.3) | <0.001 |
| Serum interleukin-6, pg/mL | 2.6 (±1.7) | 2.4 (±1.9) | 2.1 (±1.6) | 2.0 (±1.8) | <0.001 |
| Serum insulin, µIU/mL | 18.8 (±25.3) | 18.9 (±29.6) | 16.1 (±20.7) | 15.2 (±21.6) | <0.001 |
| Fibrinogen, mg/dL | 337 (±74) | 331 (±69) | 320 (±65) | 316 (±62) | <0.001 |
| Serum coagulation factor-VII, % | 129 (±33) | 124 (±29) | 124 (±28) | 122 (±29) | <0.001 |
| Hemoglobin, g/dL | 13.9 (±1.38) | 13.9 (±1.43) | 14.1 (±1.29) | 14.1 (±1.31) | <0.001 |
| Platelet count, 103/µL | 260 (±89) | 250 (±72) | 245 (±69) | 252 (±76) | 0.001 |
Abbreviation: MET, metabolic equivalent task; SD, standard deviation