Table 3.
Characteristics of patients with CKD and hyperkalemia (potassium > 5.0 mEq/l) by metabolic acidosis status (bicarbonate < 22 mEq/l) in 2017
| CKD patients with hyperkalemia and metabolic acidosis1 | CKD patients with hyperkalemia and without metabolic acidosis1 | p Value | |
|---|---|---|---|
| n = 1104 | n = 3402 | ||
| Demographics | |||
| Age (years), mean ± SD | 68.7 ± 14.9 | 74.0 ± 13.0 | < 0.001 |
| Female, n (%) | 519 (47.0%) | 1638 (48.1%) | 0.511 |
| Race, n (%) | |||
| White | 623 (56.4%) | 2486 (73.1%) | < 0.001 |
| Black | 463 (41.9%) | 864 (25.4%) | < 0.001 |
| Other or missing | 18 (1.6%) | 52 (1.5%) | 0.812 |
| Comorbidities | |||
| CKD stage, n (%)2 | |||
| Stage 3 | 353 (32.0%) | 2,083 (61.2%) | < 0.001 |
| Stage 4 | 340 (30.8%) | 666 (19.6%) | < 0.001 |
| Stage 5 without dialysis | 101 (9.1%) | 84 (2.5%) | < 0.001 |
| ESKD | 283 (25.6%) | 371 (10.9%) | < 0.001 |
| Missing or not stage 3–5 | 27 (2.4%) | 198 (5.8%) | < 0.001 |
| Acute kidney injury, n (%) | 498 (45.1%) | 797 (23.4%) | < 0.001 |
| Type II diabetes, n (%) | 691 (62.6%) | 1917 (56.3%) | < 0.001 |
| Heart failure, n (%) | 386 (35.0%) | 1061 (31.2%) | 0.020 |
| Hypertension, n (%) | 1060 (96.0%) | 3184 (93.6%) | 0.003 |
| CCI, mean ± SD | 3.8 ± 2.3 | 3.2 ± 2.1 | < 0.001 |
| RAASi utilization, n (%) | |||
| Any RAASi | 600 (54.3%) | 2,036 (59.8%) | 0.001 |
| Hyperkalemia treatments, n (%) | |||
| Any potassium-binding treatment3 | 343 (31.1%) | 358 (10.5%) | < 0.001 |
| Any diuretics | 676 (61.2%) | 1,769 (52.0%) | < 0.001 |
| Temporizing agents | |||
| Albuterol | 235 (21.3%) | 547 (16.1%) | < 0.001 |
| Calcium | 197 (17.8%) | 203 (6.0%) | < 0.001 |
| Insulin with glucose | 212 (19.2%) | 234 (6.9%) | < 0.001 |
| Treatments for hyperkalemia and metabolic acidosis, n (%) | |||
| Sodium bicarbonate | 309 (28.0%) | 276 (8.1%) | < 0.001 |
| IV | 109 (9.9%) | 160 (4.7%) | < 0.001 |
| Oral | 231 (20.9%) | 135 (4.0%) | < 0.001 |
| Unknown | 18 (1.6%) | 9 (0.3%) | < 0.001 |
| Sodium citrate | 8 (0.7%) | 8 (0.2%) | 0.035 |
| Laboratory values closest to the first bicarbonate and potassium laboratory values > 5.0 mEq/l available,4 mean ± SD | |||
| Potassium (mEq/l) | 5.4 ± 0.4 | 5.3 ± 0.3 | < 0.001 |
| Serum bicarbonate (mEq/l) | 20.4 ± 3.0 | 26.1 ± 2.6 | < 0.001 |
| E GFR (ml/min/1.73m2)5 | 29.4 ± 15.9 | 39.6 ± 15.7 | < 0.001 |
CCI Charlson Comorbidity Index, CKD chronic kidney disease, eGFR estimated glomerular filtration rate, ESKD end-stage kidney disease, IV intravenous, N number, RAASi renin-angiotensin-aldosterone system inhibitor, SD standard deviation
1Patient characteristics in 2017 are included in the table
2CKD stage in 2017 is reported in the table. The most severe CKD stage observed in 2017 was included as the stage of CKD (≥ 1 eGFR or ≥ 1 diagnosis code). Missing CKD stage indicates that no data on stage were available in 2017 or that CKD was stages 1 or 2. CKD stage 3 was defined as a diagnosis code for CKD stage 3 or eGFR 30–59 ml/min/1.73 m2. CKD stage 4 was defined as a diagnosis code for CKD stage 4 or eGFR 15–29 ml/min/1.73 m2. CKD stage 5 was defined as a diagnosis code for CKD stage 5 or eGFR < 15 ml/min/1.73 m2 and no dialysis. ESKD was defined as a diagnosis code for CKD stage 5 or eGFR < 15 ml/min/1.73 m2 and dialysis
3Potassium-binding treatments include sodium polystyrene sulfonate and patiromer
4The potassium and bicarbonate laboratory values were characterized using the first pair of potassium and bicarbonate laboratory values on the same day in 2017 where the potassium laboratory value indicated hyperkalemia (> 5.0 mEq/l)
5eGFR was available for 1102 patients with metabolic acidosis and 3398 patients without metabolic acidosis. The eGFR value closest to the first pair of bicarbonate and potassium laboratory results available in 2017 is included