Table 1. Characteristics of patients treated with calcium acetate or with sevelamer.
| Characteristic | Main Cohort (n = 35,251) | Propensity Score-Matched Cohort (n = 31,776) | |||||
|---|---|---|---|---|---|---|---|
| Sevelamer | Calcium | P | Standardized Difference (%)a | Sevelamer | Calcium | Standardized Difference (%)a | |
| No. of participants | 16,916 | 18,335 | 15,888 | 15,888 | |||
| Age (y) | 75.6 ±6.6 | 75.4 ±6.5 | <0.001 | 4.1 | 75.6 ±6.6 | 75.5 ±6.6 | 1.7 |
| Female sex | 55.3 | 50.7 | <0.001 | 9.1 | 53.9 | 53.5 | 0.8 |
| Race | <0.001 | 4.1 | 1.5 | ||||
| Black | 26.4 | 24.6 | 25.9 | 25.2 | |||
| White | 67.2 | 69.3 | 67.7 | 68.6 | |||
| Asian | 5.7 | 5.2 | 5.8 | 5.3 | |||
| Other | 0.7 | 1.0 | 0.7 | 1.0 | |||
| Hispanic ethnicity | 13.1 | 16.1 | <0.001 | 8.4 | 13.7 | 13.5 | 0.7 |
| Diabetes as primary cause of ESRD | 45.9 | 47.7 | 0.001 | 3.8 | 46.5 | 46.5 | 0.0 |
| Dialysis vintage (d) | 59 [4-176] | 43 [3-156] | <0.001 | 20.1 | 55 [4-156] | 52 [4-159] | 1.5 |
| Vascular access via catheterb | 68.5 | 72.7 | <0.001 | 9.2 | 69.9 | 70.4 | 1.1 |
| Hematocrit (%)b | 32.1 [24.0-40.5] | 31.5 [23.7-39.9] | <0.001 | 3.7 | 32.1 [24.0-40.2] | 31.8 [24.0-39.9] | 2.3 |
| Medication usec | |||||||
| Vitamin D | 37.8 | 30.8 | <0.001 | 14.8 | 35.5 | 34.8 | 1.6 |
| β blockers | 64.3 | 65.5 | 0.01 | 2.7 | 64.6 | 65.3 | 1.4 |
| ACEi/ARBs/renin inhibitors | 41.1 | 42.1 | 0.05 | 2.1 | 41.3 | 41.7 | 0.7 |
| Dihydropyridine CCB | 48.7 | 50.1 | 0.01 | 2.8 | 48.9 | 49.4 | 0.9 |
| Non-dihydropyridine CCB | 9.8 | 9.6 | 0.5 | 0.7 | 9.8 | 9.7 | 0.5 |
| Statin | 48.3 | 46.1 | <0.001 | 4.5 | 47.8 | 47.8 | 0.1 |
| Cinacalcet | 3.2 | 2.0 | <0.001 | 7.8 | 2.4 | 2.3 | 1.0 |
| ESAd | 51.9 | 44.9 | <0.001 | 6.2 | 49.9 | 49.2 | 1.3 |
| Hospitalizede | 70.7 | 71.0 | 0.6 | 0.6 | 70.7 | 70.5 | 0.4 |
| Comorbid conditionsf | |||||||
| Atherosclerotic heart disease | 37.7 | 36.6 | 0.02 | 2.4 | 37.6 | 37.5 | 0.1 |
| Congestive heart failure | 45.0 | 43.0 | <0.001 | 4.1 | 44.7 | 43.7 | 1.9 |
| CVA/TIA | 13.2 | 12.3 | 0.01 | 2.6 | 12.9 | 12.7 | 0.6 |
| PVD | 24.1 | 22.3 | <0.001 | 4.3 | 23.7 | 23.1 | 1.4 |
| Other cardiac disease | 28.6 | 27.0 | 0.001 | 3.7 | 28.1 | 28.1 | 0.0 |
| COPD | 20.5 | 19.8 | 0.1 | 1.7 | 20.3 | 20.5 | 0.3 |
| GI disease | 8.4 | 7.8 | 0.05 | 2.1 | 8.4 | 8.0 | 1.4 |
| Liver disease | 3.8 | 3.5 | 0.1 | 1.6 | 3.7 | 3.7 | 0.0 |
| Dysrhythmia | 29.4 | 27.4 | <0.001 | 4.5 | 28.7 | 28.8 | 0.0 |
| Cancer | 8.5 | 8.0 | 0.1 | 1.6 | 8.5 | 8.0 | 1.8 |
| Diabetes | 48.5 | 46.8 | 0.001 | 3.4 | 48.1 | 47.4 | 1.5 |
Note: Values for categorical variables are given as percentages; values for continuous variables are given as mean ± standard deviation or median [5th-95th percentile].
ACEi, angiotensin-converting enzyme inhibitor; ARB, angiotensin receptor blocker; CCB, calcium channel blocker; COPD, chronic obstructive pulmonary disease; CVA, cerebrovascular accident; TIA, transient ischemic attack; ESA, erythropoiesis-stimulating agent; ESRD, end-stage renal disease; GI, gastrointestinal; PVD, peripheral vascular disease.
For each variable, standardized difference was obtained by dividing absolute difference between mean of sevelamer group and mean of calcium group by an estimate of pooled standard deviation of variable. A standardized difference <10% signifies little or no imbalance between sevelamer and calcium patients for that variable.
Most recent value before first phosphate binder use.
At least one record of medication prescription in medication class required in 90 days before first phosphate binder prescription.
Record of ESA in 180 days preceding first phosphate binder prescription.
Any hospitalization in 180 days preceding first phosphate binder prescription.
Comorbidity determined in 180 days preceding first phosphate binder prescription.