Table 1.
Baseline characteristics according to quintiles of plasma total branched-chain amino acid metabolite levels
| Participants, N | Total plasma branched-chain amino acid quintiles | p-trend* | ||||
|---|---|---|---|---|---|---|
| Q1 (bottom) | Q2 | Q3 | Q4 | Q5 (top) | ||
| 5,443 | 5,409 | 5,648 | 5,429 | 5,472 | ||
| Values are means (standard deviations) or %, unless otherwise specified | ||||||
| Age, years | 54.4 (7.2) | 54.8 (7.3) | 54.9 (7.1) | 54.9 (7.1) | 54.6 (6.9) | 0.12 |
| Body mass index, kg/m2 | 24.0 (3.9) | 24.7 (4.1) | 25.6 (4.6) | 26.7 (5.0) | 28.3 (5.7) | <0.0001 |
| Normal weight (<25) | 69.8 | 62.7 | 53.5 | 43.4 | 31.3 | <0.0001 |
| Overweight/obese (≥25) | 30.2 | 37.3 | 46.5 | 56.6 | 68.8 | |
| Menopausal status | ||||||
| Premenopausal | 31.7 | 27.8 | 26.2 | 26.4 | 26.2 | <0.0001 |
| Postmenopausal | 51.5 | 54.6 | 56.3 | 56.0 | 53.1 | 0.04 |
| Uncertain | 12.7 | 13.8 | 13.5 | 14.0 | 16.3 | <0.0001 |
| Postmenopausal hormone use | 43.4 | 44.8 | 45.5 | 43.7 | 40.7 | 0.001 |
| Family history of premature MI | 11.1 | 10.9 | 10.9 | 11.8 | 12.7 | 0.003 |
| Caucasian race/ethnicity | 95.2 | 95.4 | 94.9 | 94.1 | 93.0 | <0.0001 |
| Smoking status | ||||||
| Never | 48.6 | 51.6 | 52.1 | 53.3 | 52.8 | <0.0001 |
| Past | 38.3 | 37.2 | 37.0 | 35.6 | 35.7 | 0.0009 |
| Current, <15 cig/day | 4.7 | 4.5 | 4.1 | 3.8 | 4.4 | 0.1 |
| Current, ≥15 cig/day | 8.3 | 6.5 | 6.6 | 7.2 | 7.0 | 0.07 |
| Alcohol | ||||||
| Rarely/never | 38.6 | 40.7 | 42.7 | 45.5 | 51.9 | <0.0001 |
| 1–3 drinks/month | 12.5 | 14.0 | 13.3 | 13.1 | 13.4 | 0.6 |
| 1–6 drinks/week | 35.2 | 33.2 | 33.6 | 32.4 | 27.7 | <0.0001 |
| ≥1 drink/day | 13.7 | 12.0 | 10.4 | 9.1 | 7.1 | <0.0001 |
| AHEI diet quality score (10-100) | 54.5 (10.3) | 53.9 (10.2) | 53.7 (10.1) | 53.1 (10.1) | 52.4 (10.1) | <0.0001 |
| Total physical activity, MET-hrs/wk (median, interquartile range) | 10.3 (19.5) | 10.0 (18.2) | 9.2 (17.5) | 8.0 (17.4) | 7.0 (15.1) | <0.0001 |
| History of high cholesterol | 23.5 | 26.9 | 29.8 | 32.3 | 34.1 | <0.0001 |
| History of hypertension | 18.2 | 21.0 | 22.9 | 27.6 | 34.2 | <0.0001 |
| History of type 2 diabetes | 0.6 | 0.9 | 1.2 | 2.1 | 7.9 | <0.0001 |
| Randomized treatment assignment | ||||||
| Aspirin | 49.7 | 50.0 | 49.8 | 49.6 | 51.2 | 0.2 |
| Beta carotene | 49.6 | 50.6 | 49.7 | 49.7 | 49.4 | 0.6 |
| Vitamin E | 50.3 | 49.8 | 49.8 | 50.8 | 49.8 | 0.9 |
| Fasting at blood draw | 72.9 | 76.1 | 75.4 | 74.0 | 62.1 | <0.0001 |
| Plasma metabolite levels, umol/L (median, interquartile range) | ||||||
| Total BCAAs | 308 (41) | 360 (22) | 104 (20) | 447 (27) | 528 (78) | <0.0001 |
| Isoleucine | 35 (15) | 43 (16) | 50 (17) | 58 (18) | 76 (26) | <0.0001 |
| Leucine | 96 (25) | 117 (22) | 132 (22) | 148 (23) | 177 (34) | <0.0001 |
| Valine | 172 (27) | 199 (21) | 219 (23) | 242 (24) | 284 (43) | <0.0001 |
| Other biomarkers | ||||||
| Hba1c, % | 5.0 (0.3) | 5.0 (0.4) | 5.0 (0.4) | 5.1 (0.5) | 5.3 (1.0) | <0.0001 |
| LPIR score | 30.8 (20.5) | 35.4 (21.7) | 39.7 (22.8) | 46.2 (23.2) | 55.5 (23.5) | <0.0001 |
| Triglycerides, mg/dL | 115.6 (69.2) | 123.5 (69.5) | 133.1 (71.5) | 145.9 (77.7) | 172.9 (89.5) | <0.0001 |
| LDL-C, mg/dL | 117.5 (32.7) | 122.3 (33.1) | 125.1 (34.1) | 127.6 (33.9) | 128.7 (34.9) | <0.0001 |
| GlycA, umol/L | 357.8 (63.4) | 374.7 (64.0) | 385.4 (64.6) | 399.4 (66.1) | 416.2 (69.3) | <0.0001 |
Q=quintile, MI=myocardial infarction, AHEI=Alternative Healthy Eating Index, MET=metabolic equivalent of tasks, Hba1c=glycated haemoglobin, LPIR score=lipoprotein insulin resistance score that reflects lipoprotein derangements of insulin resistance, LDL-C=low density lipoprotein cholesterol, GlycA=glycoprotein N-acetyl methyl groups
*
We performed tests for trend across BCAA quintiles.