Table 1.
Baseline Characteristics of the 693 Patients in AASK, According to the Number of APOL1 Variants.*
| Characteristic | All Patients (N = 693) | No Copies of APOL1 Risk Variants (N = 234) | 1 Copy of APOL1 Risk Variants (N = 299) | 2 Copies of APOL1 Risk Variants (N = 160) | P Value for Trend† |
|---|---|---|---|---|---|
| Age — yr | 54.1±10.6 | 55.0±10.0 | 54.6±10.2 | 51.7±11.8 | 0.005 |
| Male sex — % | 59.7 | 65.4 | 56.9 | 56.9 | 0.07 |
| Body-mass index‡ | 31.1±6.7 | 30.1±6.0 | 31.5±6.8 | 31.7±7.2 | 0.02 |
| Glomerular filtration rate — ml/min/1.73 m2 | 47.3±13.5 | 48.0±13.9 | 48.6±12.9 | 44.0±13.6 | 0.01 |
| Serum creatinine — mg/dl | 2.0±0.7 | 2.0±0.7 | 1.9±0.6 | 2.1±0.7 | 0.03 |
| Median urinary protein-to-creatinine ratio (IQR)§ | 74.2 (27.4–307.4) | 67.9 (27.1–223.5) | 56.5 (25.1–220.1) | 203.0 (43.2–723.4) | 0.01 |
| Patients with proteinuria — %¶ | 30.4 | 25.2 | 25.1 | 48.1 | <0.001 |
| Patients with history of heart disease — % | 50.5 | 51.7 | 53.5 | 43.1 | 0.14 |
| Mean arterial pressure — mm Hg | 114.1±16.4 | 113.3±16.6 | 116.2±16.8 | 111.2±15.0 | 0.41 |
| Blood pressure — mm Hg | |||||
| Systolic | 150.4±24.3 | 149.4±25.1 | 153.5±24.4 | 146.2±22.0 | 0.37 |
| Diastolic | 95.9±14.6 | 95.2±14.3 | 97.6±15.2 | 93.7±13.7 | 0.53 |
| European ancestry — % of genetic makeup | 16.7±13.3 | 17.9±14.1 | 16.3±13.5 | 15.6±11.6 | 0.08 |
Plus–minus values are means ±SD. To convert the values for creatinine to micromoles per liter, multiply by 88.4. AASK denotes African American Study of Kidney Disease and Hypertension, and IQR interquartile range.
P values for trend were calculated by means of logistic regression, with the number of APOL1 risk-variant copies as the independent variable.
The body-mass index is the weight in kilograms divided by the square of the height in meters.
Urinary protein was measured in milligrams, and creatinine in grams.
Proteinuria was defined as a ratio of urinary protein to creatinine of at least 220, with urinary protein was measured in milligrams and creatinine in grams, or 0.22, with both levels measured in grams.