Table 2.

Association of serum bicarbonate level and low pH with incident lower extremity functional limitation

OutcomeHazard Ratio (95% Confidence Interval)
UnadjustedAdjusted for Age, Race, and SexPlus CKDPlus DM, Smoking, BMI, and Diuretic UsePlus Gait Speed
Any persistent functional limitation
 Continuous (per 1 mEq/L lower)1.07 (1.02 to 1.12)1.08 (1.04 to 1.14)1.07 (1.02 to 1.12)1.08 (1.03 to 1.14)1.07 (1.02 to 1.12)
 ≥26 mEq/L1.0 (reference)1.0 (reference)1.0 (reference)1.0 (reference)1.0 (reference)
 23–25.9 mEq/L1.19 (0.96 to 1.47)1.26 (1.02 to 1.56)1.23 (1.00 to 1.53)1.32 (1.05 to 1.65)1.35 (1.08 to 1.68)
 <23 mEq/L1.61 (1.17 to 2.21)1.69 (1.23 to 2.34)1.58 (1.14 to 2.18)1.68 (1.20 to 2.24)1.58 (1.12 to 2.22)
 pH<7.401.23 (1.00 to 1.52)1.08 (0.87 to 1.34)1.03 (0.83 to 1.28)1.15 (0.92 to 1.44)1.10 (0.88 to 1.38)
Severe persistent functional limitation
 ≥26 mEq/L1.0 (reference)1.0 (reference)1.0 (reference)1.0 (reference)1.0 (reference)
 23–25.9 mEq/L1.05 (0.71 to 1.56)1.09 (0.74 to 1.62)1.07 (0.72 to 1.59)1.12 (0.74 to 1.69)1.14 (0.75 to 1.71)
 <23 mEq/L2.02 (1.19 to 3.45)2.10 (1.23 to 3.59)1.87 (1.09 to 3.23)1.85 (1.04 to 3.27)1.73 (0.98 to 3.08)
 pH<7.401.46 (1.20 to 1.78)1.23(1.05 to 1.58)1.37 (1.00 to 1.51)1.32 (1.08 to 1.63)1.31 (1.06 to 1.61)
  • DM, diabetes; BMI, body mass index.