Table 1.
Participant Characteristics by Serum Bicarbonate Category
| Characteristic | Serum Bicarbonate (mEq/L) | P | |
|---|---|---|---|
| <23 | ≥23 | ||
| Number | 618 | 2057 | |
| Age (years) | 62.3 +/− 0.5 | 63.3 +/−0.3 | 0.08 |
| Women | 51.8 +/− 2.2 | 50.6 +/−0.9 | 0.7 |
| Race/Ethnicity | 0.2 | ||
| Non-Hispanic White | 80.0 +/− 3.6 | 81.3 +/−1.9 | |
| Mexican American | 5.0 +/− 1.6 | 3.0 +/−0.6 | |
| Non-Hispanic Black | 6.3 +/− 1.2 | 7.6 +/−1.2 | |
| Body-mass index (kg/m2) | 29.6 +/−0.4 | 28.2 +/−0.2 | <0.001 |
| Poverty* | 12.8 +/−1.9 | 8.8 +/−1.3 | 0.05 |
| Less than high-school diploma | 26.3 +/−1.9 | 22.4 +/−2.2 | 0.2 |
| Married or living with partner | 71.9 +/−2.9 | 70.8 +/−1.5 | 0.8 |
| Activity Level | 0.5 | ||
| 0 MET-min/wk | 22.7 +/−2.7 | 19.0 +/−2.0 | |
| < 500 MET-min/wk | 20.7 +/−2.1 | 19.5 +/−1.0 | |
| 500 – 2000 MET-min/wk | 29.6 +/−3.0 | 34.4 +/−1.2 | |
| > 2000 MET-min/wk | 27.0 +/−2.8 | 27.0 +/−1.8 | |
| Muscle strengthening activities | 16.3 +/−2.4 | 20.0 +/−2.1 | 0.2 |
| Smoking | 0.4 | ||
| Never | 43.2 +/− 3.8 | 47.2 +/−1.3 | |
| Former | 38.4 +/−3.0 | 38.0 +/−1.4 | |
| Current | 18.4 +/−2.5 | 14.8 +/−1.1 | |
| Alcohol intake | 0.1 | ||
| None | 46.1 +/−5.1 | 36.4 +/−2.5 | |
| < 2 drinks/day | 47.2 +/−4.5 | 56.2 +/−2.3 | |
| ≥ 2 drinks/day | 6.7 +/−0.9 | 7.4 +/−0.9 | |
| Dietary Protein (g/day) | 75.4 +/−1.6 | 75.0 +/−1.1 | 0.9 |
| Diuretic use | 14.7 +/−2.0 | 21.2 +/−1.5 | 0.007 |
| Hypertension | 63.9 +/−2.4 | 63.9 +/−1.3 | 0.9 |
| Diabetes Mellitus | 16.6 +/−2.0 | 10.7 +/−0.8 | 0.01 |
| Cardiovascular Disease | 18.7 +/−1.9 | 15.3 +/−1.0 | 0.08 |
| Thyroid Disease | 14.9 +/−1.7 | 11.5 +/−0.7 | 0.03 |
| Liver Disease | 5.7 +/−1.4 | 3.3 +/−0.6 | 0.05 |
| Arthritis | 43.8 +/−2.8 | 38.3 +/−1.6 | 0.1 |
| eGFR < 60 mL/min/1.73m2 | 18.1 +/−1.4 | 13.3 +/−1.0 | 0.002 |
| UACR ≥ 30 mg/g | 15.8 +/−1.5 | 13.1 +/−0.8 | 0.2 |
| Serum Albumin (g/dL) | 4.31 +/−0.02 | 4.27 +/−0.01 | 0.05 |
| Serum Calcium (mg/dL) | 9.4 +/−0.04 | 9.5 +/−0.02 | 0.2 |
| Hemoglobin (g/dL) | 14.5 +/−0.1 | 14.4 +/−0.04 | 0.7 |
| C-reactive protein ≥ 1.0 mg/dL | 13.2 +/−1.8 | 10.0 +/−0.9 | 0.07 |
Note: Conversion factors for units: albumin and hemoglobin in g/dL to g/L, ×10; calcium in mg/dL to mmol/L, ×0.25; C-reactive protein in mg/dL to mg/L, ×10; no conversion necessary for bicarbonate levels in mEq/L and mmol/L.
*
<100% poverty index
Abbreviations: MET, metabolic equivalent; eGFR, estimated glomerular filtration rate; UACR, urinary albumin-creatinine ratio.
Continuous data are expressed as mean +/− standard error and categorical data as percent +/− standard error.