Table 1.
Baseline characteristics
| Characteristic | Total Cohort, n=488 | SQ Yes, n=317 | SQ No, n=171 | P Value |
|---|---|---|---|---|
| Age, yr | 71 (65–77) | 69 (65–75) | 74 (68–80) | <0.001 |
| Women | 249 (51) | 164 (52) | 85 (50) | 0.70 |
| Race | 0.80 | |||
| White | 404 (83) | 261 (83) | 143 (84) | |
| Black | 82 (17) | 54 (17) | 28 (16) | |
| Marital status | 0.07 | |||
| Married | 301 (63) | 197 (63) | 104 (62) | |
| Divorced/separated | 53 (11) | 42 (13) | 11 (7) | |
| Widow/widower | 105 (22) | 61 (19) | 44 (26) | |
| Single | 21 (4) | 13 (4) | 8 (5) | |
| Insurance | 0.06 | |||
| Medicare | 397 (81) | 248 (78) | 149 (87) | |
| Private | 87 (18) | 66 (21) | 21 (12) | |
| Medicaid/self-pay | 4 (1) | 3 (1) | 1 (1) | |
| Time since first visit with provider, mo | 22(7–57) | 27 (9–62) | 14 (5–45) | 0.002 |
| Length of follow-up, yr | 1.9 (1.5–2.1) | 2.0 (1.6–2.2) | 1.9 (1.2–2.1) | <0.001 |
| CCI | 5 (4–7) | 5 (4–6) | 6 (5–8) | <0.001 |
| Comorbidities | ||||
| Diabetes | 268 (55) | 167 (53) | 101 (59) | 0.20 |
| Hypertension | 480 (98) | 312 (98) | 168 (98) | 0.90 |
| Coronary artery disease | 197 (40) | 109 (34) | 88 (51) | <0.001 |
| Congestive heart failure | 154 (32) | 80 (25) | 74 (43) | <0.001 |
| Peripheral vascular disease | 104 (21) | 59 (19) | 45 (26) | 0.05 |
| Active cancer | 81 (17) | 45 (14) | 36 (21) | 0.05 |
| CKD etiology | ||||
| Diabetes | 234 (48) | 144 (45) | 90 (53) | 0.10 |
| Hypertension | 366 (75) | 231 (73) | 135 (79) | 0.10 |
| Analgesic nephropathy | 41 (8) | 30 (9) | 11 (6) | 0.30 |
| Cardiorenal | 44 (9) | 14 (4) | 30 (18) | <0.001 |
| Renal artery stenosis | 39 (8) | 22 (7) | 17 (10) | 0.20 |
| AKI | 85 (17) | 47 (15) | 38 (22) | 0.04 |
| Glomerular disease | 34 (7) | 26 (8) | 8 (5) | 0.10 |
| BMI | 29 (25–34) | 30 (26–35) | 28(24–32) | 0.001 |
| Laboratory tests | ||||
| eGFR, ml/min per 1.73 m2 | 22 (16–26) | 23 (17–27) | 20 (15–25) | 0.001 |
| Serum creatinine, mg/dl | 2.5 (2.1–3.2) | 2.5 (2.1–3.1) | 2.7 (2.2–3.6) | 0.01 |
| Serum albumin, g/dl | 4.0 (3.7–4.2) | 4.0 (3.8–4.2) | 3.9 (3.6–4.1) | <0.001 |
| Hemoglobin, g/dl | 11.5 (10.4–12.7) | 11.8 (10.9–12.8) | 11.0 (9.8–12.3) | <0.001 |
| Urine protein-to-creatinine ratio, mg/g | 41 (12–1560) | 29 (10–96) | 65 (15–2300) | <0.001 |
Continuous variables are presented as medians (interquartile ranges), and categorical variables are presented as N (%). SQ, surprise question; CCI, Charlson Comorbidity Index; BMI, body mass index.