Background
Materials
Study population
Data collection
Outcome measures
Statistical analysis
Results
Patient characteristics
Age (years) | 56.0 ± 16.6 |
Female – n (%) | 74 (40.9) |
Race/ethnicity – n (%) | |
Black | 79 (43.7) |
Hispanic | 71 (39.2) |
Caucasian | 22 (12.1) |
Other | 9 (5.0) |
Hypertension – n (%) | 176 (97.2) |
Diabetes Mellitus – n (%) | 108 (59.7) |
Cardiovascular Disease – n (%) | 116 (64.1) |
Chronic Obstructive Pulmonary Disease– n (%) | 15 (8.3) |
Smoking – n (%) | |
Current | 24 (13.3) |
Former | 33 (18.2) |
Never | 53 (29.3) |
Unknown | 71 (39.2) |
Body Mass Index - kg/m2 – n (%) | |
Underweight (≤18.49) | 4 (2.2) |
Normal (18.5 – 24.9) | 62 (34.3) |
Overweight (25 – 29.9) | 64 (35.4) |
Obese (≥30) | 51 (28.2) |
ESRD Etiology – n (%) | |
Diabetes | 87 (48.1) |
Hypertension | 45 (24.9) |
Glomerulonephritis | 12 (6.6) |
Polycystic Kidney Disease | 3 (1.7) |
Lupus | 8 (4.4) |
HIV | 7 (3.9) |
Other/Unknown | 19 (10.5) |
Initial Access Type – n (%) | |
Catheter | 75 (41.4) |
AVF | 66 (36.5) |
AVG | 40 (22.1) |
Medication use – n (%) | |
Diuretic | 25 (13.8) |
ACE inhibitor or ARB | 63 (34.8) |
Beta blocker | 133 (73.5) |
Calcium Channel Blocker | 109 (60.2) |
Statin | 93 (51.4) |
Proton Pump Inhibitor | 51 (28.2) |
H2 Blocker | 10 (5.5) |
Phosphate binder– n (%)a
| |
Sevelamer Hydrochloride | 76 (42.0) |
Calcium Acetate | 38 (21.0) |
Sevelamer Carbonate | 21 (11.6) |
Lanthanum Carbonate | 6 (3.3) |
Calcium Carbonate | 6 (3.3) |
None | 34 (18.8) |
Epoetin alpha dose (Units) | |
≤5000 | 57 (31.5) |
>5000 – ≤10,000 | 96 (53.0) |
≥10,000 | 28 (15.5) |
Interdialytic weight gain (kg) | 2.77 ± 0.93 |
Dialysis treatment time (min) | 228.4 ± 18.0 |
Blood flow rate (mL/min) | 382 ± 31 |
Dialysate flow rate (mL/min) | 603 ± 33 |
Serum bicarbonate (mEq/L)b
| 23.0 ± 2.2 |
Serum potassium (mEq/L)b
| 4.6 ± 0.6 |
Serum albumin (mg/dL)b
| 3.7 ± 0.5 |
Serum calcium (mg/dL)b
| 8.9 ± 0.6 |
Serum phosphate (mg/dL)b
| 5.1 ± 1.2 |
Serum hemoglobin (g/dL)b
| 10.8 ± 1.2 |
Serum creatinine (mg/dL)b
| 8.0 ± 2.9 |
WBC (103/mm3)b
| 7.5 ± 2.1 |
nPCR (g/kg/day)b
| 0.82 ± 0.18 |
spKt/Vb
| 1.6 ± 0.28 |
Associations of patient characteristics with serum bicarbonate levels
Unadjusted | Multivariable-adjusted | |||
---|---|---|---|---|
Coefficient (95 % CI) |
p
| Coefficient (95 % CI) |
p
| |
Age (per 10 years) |
0.45 (0.29 to 0.61)
| <0.001 | 0.07 (−0.10 to 0.25) | 0.41 |
Male | −0.54 (−1.12 to 0.05) | 0.07 | 0.09 (−0.45 to 0.63) | 0.75 |
Race/ethnicity | ||||
White | −0.18 (−1.12 to 0.75) | 0.70 | −0.61 (−1.45 to 0.23) | 0.16 |
Hispanic/Other | −0.44 (−1.06 to 0.17) | 0.16 | −0.28 (−0.83 to 0.26) | 0.31 |
BMI | ||||
Overweight | 0.06 (−0.63 to 0.74) | 0.87 | −0.14 (−0.74 to 0.46) | 0.66 |
Obese | −0.01 (−0.74 to 0.72) | 0.97 | 0.16 (−0.48 to 0.80) | 0.62 |
Dialysis access | ||||
AVG | 0.22 (−0.20 to 0.64) | 0.31 | −0.18 (−0.60 to 0.24) | 0.40 |
Tunneled catheter |
0.33 (0.01 to 0.64)
| 0.04 | 0.11 (−0.21 to 0.43) | 0.50 |
Etiology of ESRD | ||||
Diabetes | 0.50 (−0.20 to 1.21) | 0.16 | 0.38 (−0.26 to 1.02) | 0.24 |
Other/Unknown | −0.21 (−1.00 to 0.58) | 0.60 | 0.31 (−0.46 to 1.08) | 0.43 |
Cardiovascular Disease |
0.90 (0.31 to 1.48)
| 0.003 | 0.41 (−0.18 to 1.01) | 0.17 |
Phosphate binder | ||||
>6 pills/day acid precursor |
−1.00 (−1.45 to−0.55)
| <0.001 |
−0.49 (−0.95 to−0.03)
| 0.04 |
>3−6 pills/day acid precursor | −0.39 (−0.81 to 0.03) | 0.07 | 0.02 (−0.41 to 0.44) | 0.9 |
≤3 pills/day acid precursor | 0.002 (−0.38 to 0.39) | 0.9 | 0.27 (−0.13 to 0.66) | 0.19 |
≤3 pills/day base precursor | 0.004 (−0.37 to 0.37) | 0.9 | 0.29 (−0.08 to 0.66) | 0.12 |
>3–6 pills/day base precursor | 0.04 (−0.35 to 0.43) | 0.84 | 0.36 (−0.04 to 0.75) | 0.08 |
>6 pills/day base precursor | −0.23 (−0.61 to 0.15) | 0.24 | 0.08 (−0.33 to 0.49) | 0.70 |
IDW gain (kg) | ||||
>1–3 |
−0.28 (−0.60 to 0.05)
| 0.10 | 0.26 (−0.04 to 0.56) | 0.08 |
>3–7 |
−0.65 (−1.01 to−0.30)
| <0.001 | 0.15 (−0.18 to 0.47) | 0.38 |
Epoetin alpha dose (Units) | ||||
≤5000 | 0.11 (−0.11 to 0.32) | 0.33 | −0.01 (−0.20 to 0.19) | 0.9 |
>5000 – ≤10,000 | 0.16 (−0.09 to 0.40) | 0.16 | 0.05 (−0.18 to 0.28) | 0.69 |
≥10,000 | 0.04 (−0.30 to 0.38) | 0.83 | −0.11 (−0.43 to 0.20) | 0.47 |
spKt/V | ||||
1.52–1.70 | 0.12 (−0.8 to 0.32) | 0.25 |
0.25 (0.06 to 0.44)
| 0.009 |
≥1.71 |
0.31 (0.07 to 0.55)
| 0.01 |
0.39 (0.16 to 0.62)
| 0.001 |
nPCR (g/kg/day) |
−3.14 (−3.54 to−2.75)
| <0.001 |
−1.08 (−1.52 to −0.64)
| <0.001 |
Serum albumin (g/dL) |
−1.06 (−1.32 to−0.80)
| <0.001 |
−0.84 (−1.15 to −0.52)
| <0.001 |
Hemoglobin (g/dL) |
−0.25 (−0.30 to −0.19)
| <0.001 |
−0.14 (−0.19 to −0.08)
| <0.001 |
K+ (mEq/L) |
−1.13 (−1.25 to −1.00)
| <0.001 |
−0.70 (−0.83 to −0.57)
| <0.001 |
Calcium (mg/dL) |
0.74 (0.62 to 0.87)
| <0.001 |
0.95 (0.82 to 1.08)
| <0.001 |
Phosphorus (mg/dL) |
−0.63 (−0.68 to −0.57)
| <0.001 |
−0.39 (−0.45 to −0.32)
| <0.001 |
WBC (103/mm3) | ||||
6.26–8.25 | −0.14 (−0.36 to 0.09) | 0.23 | 0.26 (−0.04 to 0.56) | 0.08 |
≥8.26 |
−0.35 (−0.64 to −0.08)
| 0.01 |
−0.35 (−0.61 to −0.10)
| 0.007 |
Serum creatinine (mg/dL) |
−0.33 (−0.37 to −0.29)
| <0.001 |
−0.14 (−0.19 to −0.08)
| <0.001 |
Time (months) | 0.003 (−0.004 to 0.01) | 0.40 |
0.02 (0.01 to 0.03)
| <0.001 |
Monthly serum bicarbonate variability
Number of patients | Number of observations (bicarbonate/albumin) | Serum bicarbonate | Serum albumin | |
---|---|---|---|---|
Overall | 181 | 4104/4099 | 0.38 | 0.68 |
0–6 months | 181 | 1160/1156 | 0.34 | 0.68 |
>6–12 months | 156 | 849/849 | 0.47 | 0.74 |
>12–18 months | 117 | 609/609 | 0.51 | 0.78 |
>18–24 months | 93 | 526/525 | 0.53 | 0.80 |
>24–30 months | 70 | 373/373 | 0.57 | 0.73 |
>30–36 months | 53 | 277/277 | 0.41 | 0.64 |
>36 months | 36 | 310/310 | 0.54 | 0.61 |
Associations of patient characteristics with monthly bicarbonate variability
Overall | ≤12 months | >12 months | ||||
---|---|---|---|---|---|---|
Coefficient (95 % CI) |
p
| Coefficient (95 % CI) |
p
| Coefficient (95 % CI) |
p
| |
Age (per 10 years) |
−0.03 (−0.04 to −0.01)
| 0.009 |
−0.03 (−0.05 to 0.00)
| 0.03 | 0.00 (−0.03 to 0.03) | 0.9 |
Male | −0.04 (−0.09 to 0.02) | 0.19 |
−0.09 (−0.16 to −0.01)
| 0.02 | 0.02 (−0.05 to 0.09) | 0.65 |
Race/ethnicity | ||||||
White | −0.03 (−0.11 to 0.06) | 0.53 | −0.03 (−0.13 to 0.08) | 0.64 | −0.07 (−0.17 to 0.04) | 0.22 |
Hispanic/Other | −0.03 (−0.09 to 0.03) | 0.31 | −0.04 (−0.11 to 0.03) | 0.24 | 0.00 (−0.07 to 0.08) | 0.9 |
BMI | ||||||
Overweight | 0.01 (−0.05 to 0.07) | 0.78 | 0.02 (−0.06 to 0.09) | 0.65 | 0.02 (−0.05 to 0.10) | 0.56 |
Obese | −0.02 (−0.09 to 0.04) | 0.52 | −0.01 (−0.09 to 0.07) | 0.83 | −0.01 (−0.10 to 0.07) | 0.77 |
Dialysis access | ||||||
AVG |
0.06 (0.00 to 0.11)
| 0.04 | 0.01 (−0.06 to 0.09) | 0.75 |
0.07 (0.00 to 0.14)
| 0.04 |
Tunneled catheter | 0.04 (−0.01 to 0.09) | 0.15 | 0.00 (−0.07 to 0.07) | 0.9 |
0.19 (0.09 to 0.28)
| <0.001 |
Etiology of ESRD | ||||||
Diabetes | −0.03 (−0.09 to 0.04) | 0.41 | −0.04 (−0.12 to 0.04) | 0.33 | 0.03 (−0.06 to 0.11) | 0.54 |
Other/Unknown | −0.06 (−0.14 to 0.01) | 0.11 | −0.08 (−0.18 to 0.01) | 0.09 | 0.00 (−0.09 to 0.10) | 0.9 |
Cardiovascular Disease | 0.05 (−0.01 to 0.11) | 0.13 | 0.06 (−0.02 to 0.13) | 0.13 | 0.04 (−0.04 to 0.11) | 0.32 |
Phosphate binder | ||||||
>6 pills/day acid precursor | −0.03 (−0.11 to 0.05) | 0.50 | 0.05 (−0.07 to 0.17) | 0.39 | −0.09 (−0.21 to 0.04) | 0.19 |
>3–6 pills/day acid precursor | −0.05 (−0.12 to 0.03) | 0.21 | 0.04 (−0.07 to 0.14) | 0.50 | −0.12 (−0.25 to 0.01) | 0.06 |
≤3 pills/day acid precursor |
−0.09 (−0.16 to −0.02)
| 0.01 | −0.06 (−0.15 to 0.02) | 0.16 | −0.12 (−0.24 to 0.01) | 0.07 |
≤3 pills/day base precursor | −0.04 (−0.11 to 0.02) | 0.21 | −0.02 (−0.10 to 0.06) | 0.60 | −0.06 (−0.18 to 0.06) | 0.31 |
>3–6 pills/day base precursor | −0.07 (−0.14 to 0.00) | 0.07 | 0.00 (−0.10 to 0.09) | 0.95 |
−0.14 (−0.26 to −0.01)
| 0.03 |
>6 pills/day base precursor |
−0.08 (−0.15 to 0.00)
| 0.04 | −0.06 (−0.16 to 0.05) | 0.30 | −0.11 (−0.23 to 0.01) | 0.07 |
Epoetin alpha dose (Units) | ||||||
≤5000 |
0.05 (0.02 to 0.09)
| 0.005 | −0.02 (−0.07 to 0.04) | 0.57 |
0.10 (0.05 to 0.15)
| <0.001 |
>5000 – ≤10,000 | 0.03 (−0.02 to 0.07) | 0.23 | 0.01 (−0.05 to 0.07) | 0.81 | 0.03 (−0.04 to 0.09) | 0.44 |
≥10,000 |
0.06 (0.00 to 0.12)
| 0.04 | −0.02 (−0.10 to 0.06) | 0.65 |
0.16 (0.07 to 0.25)
| <0.001 |
Serum bicarbonate (mEq/L) | ||||||
<22 |
0.12 (0.09 to 0.15)
| <0.001 |
0.17 (0.13 to 0.22)
| <0.001 |
0.08 (0.03 to 0.12)
| 0.001 |
>26 |
0.24 (0.18 to 0.29)
| <0.001 |
0.23 (0.16 to 0.31)
| <0.001 |
0.25 (0.18 to 0.32)
| <0.001 |
Serum albumin (g/dL) | 0.03 (−0.02 to 0.09) | 0.25 |
0.07 (0.00 to 0.15)
| 0.04 | −0.04 (−0.13 to 0.04) | 0.32 |
nPCR (g/kg/day) |
−0.42 (−0.73 to −0.10)
| 0.009 | −0.23 (−0.80 to 0.33) | 0.42 |
−0.46 (−0.84 to −0.07)
| 0.02 |
nPCR2 ((g/kg/day)2) |
0.19 (0.04 to 0.34)
| 0.01 | 0.09 (−0.20 to 0.37) | 0.55 |
0.21 (0.04 to 0.38)
| 0.02 |
spKt/V | 0.04 (−0.02 to 0.10) | 0.18 | 0.04 (−0.04 to 0.11) | 0.35 | 0.04 (−0.04 to 0.12) | 0.34 |
K+ (mEq/L) | −0.18 (−0.36 to 0.00) | 0.05 | −0.10 (−0.36 to 0.16) | 0.47 | −0.23 (−0.48 to 0.02) | 0.07 |
K+2 ((mEq/L)2) |
0.02 (0.00 to 0.04)
| 0.05 | 0.01 (−0.02 to 0.03) | 0.49 | 0.02 (0.00 to 0.05) | 0.05 |
Hemoglobin (g/dL) |
−0.02 (−0.03 to −0.01)
| 0.002 |
−0.04 (−0.05 to −0.02)
| <0.001 | 0.00 (−0.02 to 0.02) | 0.9 |
Calcium (mg/dL) |
−0.34 (−0.57 to −0.12)
| 0.003 |
−0.48 (−0.74 to −0.22)
| <0.001 | −0.09 (−0.55 to 0.38) | 0.71 |
Calcium2 ((mg/dL)2) |
0.02 (0.01 to 0.03)
| 0.002 |
0.03 (0.01 to 0.04)
| <0.001 | 0.01 (−0.02 to 0.03) | 0.65 |
Phosphorus (mg/dL) | 0.01 (0.00 to 0.02) | 0.09 | 0.00 (−0.02 to 0.01) | 0.64 |
0.03 (0.01 to 0.04)
| <0.001 |
Serum creatinine (mg/dL) |
0.01 (0.00 to 0.02)
| 0.03 | 0.01 (0.00 to 0.02) | 0.19 | 0.01 (0.00 to 0.02) | 0.11 |
WBC (103/mm3) | 0.01 (0.00 to 0.01) | 0.17 | 0.01 (0.00 to 0.02) | 0.13 | 0.00 (−0.01 to 0.01) | 0.79 |
IDW gain (kg) | ||||||
>1–3 | 0.01 (−0.05 to 0.07) | 0.8 | −0.03 (−0.12 to 0.05) | 0.41 | 0.04 (−0.05 to 0.12) | 0.38 |
>3–7 | 0.02 (−0.04 to 0.09) | 0.48 | −0.03 (−0.12 to 0.06) | 0.55 | 0.07 (−0.02 to 0.15) | 0.15 |
Time (months) | ||||||
>3–6 |
−0.05 (−0.11 to 0.00)
| 0.04 | −0.05 (−0.11 to 0.00) | 0.06 | …. | |
>6–12 |
−0.09 (−0.14 to −0.04)
| <0.001 |
−0.10 (−0.15 to −0.04)
| 0.001 | …. | |
>12–24 |
−0.12 (−0.18 to −0.07)
| <0.001 | …. | ref | ||
>24 |
−0.14 (−0.20 to −0.07)
| <0.001 | …. | 0.00 (−0.04 to 0.04) | 0.88 |