Table 2.

Baseline characteristics presented as mean (SD) or number (percentage) unless otherwise specified

Characteristics and MeasurementsTotal Population, n=1044Daily UAG Tertiles
−80 to <29 mEq/d n=348 29 to <50 mEq/d n=34850–228 mEq/d n=348
Demographics
 Age, yr54 (11)54 (10)55 (11)53 (11)
 Men, no. (%)645 (62)178 (51)202 (58)265 (76)
Clinical characteristics
 Body mass index, kg/m230.6 (6.6)28.8 (6.4)30.8 (6.6)32.2 (6.5)
 Cardiovascular disease, no. (%)538 (52)186 (53)177 (51)175 (50)
 Current smoker, no. (%)305 (29)134 (39)85 (24)86 (24)
 Past smoker, no. (%)298 (29)83 (24)102 (29)113 (32)
 Never smoker, no. (%)441 (42)131 (38)161 (46)149 (43)
 Systolic BP, mmHg150 (24)150 (25)150 (24)151 (22)
 Protein intake, g/d69 (25)51 (16)68 (18)88 (25)
 Net endogenous acid production, mEq/d83 (37)96 (42)83 (34)69 (27)
 ACE-i/ARB use, no. (%)397 (39)125 (37)135 (40)137 (40)
 Diuretic use, no. (%)649 (64)206 (61)212 (62)231 (68)
 Measured GFR, ml/min per 1.73 m247 (14)46 (14)46 (14)48 (13)
 Measured GFR <30 ml/min per 1.73 m2, no. (%)163 (16)60 (17)62 (18)41 (12)
Serum measurements
 Bicarbonate, mEq/L25 (3)25 (3)25 (3)25 (3)
 Bicarbonate <22 mEq/L, no. (%)128 (12)55 (16)35 (10)38 (11)
 Potassium, mEq/L4.2 (0.6)4.2 (0.7)4.2 (0.6)4.2 (0.6)
 Anion gap, mEq/L10 (2)10 (3)10 (2)10 (2)
Urine measurements
 Protein-to-creatinine ratio, mg/ga80 (29–342)77 (31–298)68 (27–332)100 (34–373)
 Urea nitrogen, g/d8.0 (3.7)5.4 (2.2)8.0 (2.6)10.8 (3.7)
 Sodium, mEq/d152 (81)111 (69)147 (67)197 (82)
 Potassium, mEq/d43 (24)27 (16)40 (13)63 (25)
 Chloride, mEq/d153 (82)120 (79)148 (70)191 (82)
 Ammonium, mEq/d21 (12)19 (11)22 (11)24 (13)
 Sulfate, mEq/d29 (16)18 (10)29 (12)40 (17)
 Phosphate, mEq/d21 (10)14 (6)21 (7)29 (10)
  • UAG, urine anion gap; ACE-i, angiotensin-converting enzyme inhibitor; ARB, angiotensin receptor blocker.

  • a Presented as median (interquartile range).