Table 1.
Baseline Characteristics of Patients with Limited Insurance and Patients Dually Eligible for Medicare and Medicaid at Dialysis Initiation.
| Covariates | Limited Insurance* (n=8,286; age 60-64 y) | Medicare and Medicaid (n=10,060; age 66-70 y) | Absolute Std Diff |
|---|---|---|---|
| Patient Demographic and Socioeconomic Characteristics | |||
| Received nephrology care prior to dialysis | 56.6% | 69.9% | 0.28 |
| Age (years) | 61.9 (1.4) | 68.0 (1.4) | 4.3 |
| Female sex | 52.4% | 59.4% | 0.14 |
| Race | |||
| Asian | 4.7% | 6.6% | 0.08 |
| Black | 30.8% | 34.9% | 0.09 |
| Native American | 1.3% | 1.4% | 0.01 |
| Other | *** | *** | *** |
| White | 62.9% | 56.9% | 0.12 |
| Hispanic ethnicity | 26.2% | 22.7% | 0.08 |
| Median income (in 1,000 $) in patient zip code | 46.0 (17.1) | 45.4 (17.3) | 0.04 |
| Patient Health Characteristics | |||
| Diabetes | 66.2% | 70.0% | 0.08 |
| Coronary heart disease | 17.6% | 23.9% | 0.16 |
| Cancer | 4.3% | 5.5% | 0.06 |
| Heart failure | 32.4% | 38.5% | 0.13 |
| Lung disease | 8.2% | 12.8% | 0.15 |
| Cerebrovascular disease | 8.5% | 14.7% | 0.19 |
| Peripheral vascular disease | 11.4% | 16.6% | 0.15 |
| Smokes | 8.7% | 6.6% | 0.08 |
| Drug or alcohol abuse | 2.5% | 1.7% | 0.05 |
| Immobility | 4.7% | 10.7% | 0.22 |
| BMI (kg/m2) | 29.7 (8.0) | 29.9 (8.2) | 0.02 |
| Hemoglobin (g/dL) | 9.6 (1.8) | 9.9 (1.8) | 0.12 |
| Serum albumin (g/dL) | 3.1 (0.7) | 3.2 (0.7) | 0.06 |
| Dialysis Facility and Geographic Characteristics | |||
| Facility size | |||
| <50 patients | 21.3% | 19.9% | 0.04 |
| 50 - <75 patients | 19.6% | 19.8% | 0.00 |
| 75-<100 patients | 19.7% | 18.7% | 0.03 |
| ≥100 patients | 39.4% | 41.6% | 0.05 |
| For-profit | 81.7% | 83.2% | 0.04 |
| Hospital-based | 11.7% | 10.0% | 0.05 |
| Population density | |||
| Metropolitan area | 76.9% | 75.6% | 0.03 |
| Micropolitan area** | 11.5% | 12.3% | 0.02 |
| Rural area | 4.4% | 4.7% | 0.01 |
| Small town | 7.3% | 7.4% | 0.01 |
Note: Values for categorical variables are given as percentage; values for continuous variables, as mean ± standard deviation.
“Received nephrology care prior to dialysis” has 13.1% missing; “BMI” has 0.9% missing; “Hemoglobin” has 7.9% missing; “Serum albumin” has 23.0% missing. Hemoglobin and albumin documented as zero were considered missing. Maximum hemoglobin and albumin levels were 20 g/dL and 6 g/dL, respectively; minimum hemoglobin was 2 g/dL.
BMI, body mass index; Std Diff, standardized difference
Limited insurance defined as uninsured or with Medicaid and in 90-day waiting period.
Micropolitan refers to an urban area with approximately 10,000-<50,000 population.