Table 1.

Characteristics of 23,718 incident dialysis patients according to modality status at day 90, modality switches over the first 2 years, and transplant status (Trp) in DaVita dialysis clinics from July 1, 2001 to June 30, 2006

Modality at Day 90
Incident HD Patients (n=22,360)Incident PD Patients (n=1,358)
Always HDSwitched HD to PDP ValueAlways PDSwitched PD to HDP Value
Not TrpTrpNot TrpTrpNot TrpTrpNot TrpTrp
N19,884129210919341916769577
Age (yr)64±1548±1455±1544±15<0.00162±1547±1357±1548±15<0.001
Sex (women)46%38%43%40%<0.00148%47%47%43%0.87
Diabetes mellitus64%43%52%39%<0.00159%36%57%48%<0.001
Race
Non-Hispanic white43%51%51%52%<0.00156%64%47%56%0.04
 Black30%19%25%20%<0.00116%16%23%22%0.03
 Hispanic18%18%13%14%0.00313%8.4%18%17%0.009
 Asian3%5%5%11%<0.0017%6%5%5%0.68
Employment status
 Retired56%25%43%24%<0.00156%13%43%29%<0.001
 Employed14%49%30%43%<0.00126%72%36%47%<0.001
 Unemployed29%26%28%33%0.0218%14%20%25%0.21
Primary insurance
 Medicare63%34%53%45%<0.00146%22%51%39%<0.001
 Medicaid8%4%5%7%<0.0013%1%5%1%0.06
 Other30%62%42%49%<0.00152%77%44%61%<0.001
Marital status
 Married47%60%53%59%<0.00166%72%61%59%0.16
 Divorced8%7%7%6%0.947%6%7%4%0.86
 Single27%30%28%29%0.2115%20%22%27%0.09
 Widowed18%3%11%4%<0.00111%2%10%9%0.05
Comorbidities
 AIDS0.6%0.1%0.5%0.1%0.430.8%0.1%0.8%0.1%0.75
 Atherosclerotic heart24%9%21%16%<0.00123%4%17%5%0.40
 Cancer4%2%4.5%3%<0.0014%2%4%1%0.07
 Heart failure31%11.6%23%7.5%<0.00121%4.8%17%12%<0.001
 COPD7%2%5%1%<0.0014%0.6%4%1%0.12
 Cerebral-vascular disease8%2%5%2%<0.0017%3%6%7%0.34
 HIV0.9%0.1%1.8%0.1%0.012%0.1%0.3%0.1%0.12
 Hypertension79%79%79%76%0.6280%75%84%79%0.06
 Nonambulatory4%0.4%2%0.1%<0.0012%0.1%0.4%1%0.08
 Other heart diseases5%2%4%0.1%<0.0016%2%3%1%0.06
 Peripheral vascular disease13%4.5%9.3%3%<0.00112%4%10.%3%0.006
 Smoker5%4%5%2%0.244%3%6%7%0.31
 BMI (kg/m2)a25.4 (22.0–29.9)25.4 (22.5–29.5)26.3 (22.7–30.9)25.1 (21.5–28.3)0.0125.5 (23.3–27.8)27.8 (21.7–28.3)26.0 (22.3–30.2)26.1 (21.4–34.1)0.87
Laboratory data
 nPCR (g/kg per day)0.93±0.250.98±0.20.91±0.30.93±0.2<0.0010.80±0.30.88±0.20.91±0.30.74±0.30.14
 Albumin (g/dl)3.6±0.53.8±0.43.7±0.53.9±0.4<0.0013.4±0.53.8±0.43.5±0.63.7±0.5<0.001
 Creatinine (mg/dl)6.8±2.79.1±3.07.4±3.29.1±3.7<0.0016.5±2.67.7±2.77.1±3.08.0±2.9<0.001
 Ferritin (ng/ml)a246 (126–458)195 (93–354)230 (114–453)196 (86–374)<0.001229 (132–381)249 (141–464)291 (157–473)278 (126–436)0.008
 TIBC (mg/dl)213±46227±43224±48236±40<0.001243±52257±47247±49250±490.02
 Calcium (mg/dl)9.1±0.79.3±0.79.2±0.79.3±0.6<0.0019.1±0.79.3±0.79.1±0.79.5±0.8<0.001
 Phosphorous (mg/dl)5.4±1.45.9±1.35.5±1.55.6±1.2<0.0014.9±1.25.1±1.25.0±1.35.3±1.20.04
 Intact PTH (pg/ml)a224 (128–377)238 (134–405)231 (121–399)280 (119–445)0.02182 (86–414)128 (45–278)257 (75–386)134 (62–255)0.01
 Hemoglobin (g/dl)12.1±1.412.4±1.412.2±1.512.3±1.2<0.00112.3±1.512.6±1.412.3±1.412.6±1.40.04
 White blood count (×103/μl)7.7±2.57.3±2.17.7±2.57.1±2.0<0.0017.9±3.57.2±2.17.4±2.37.6±2.30.03
 Lymphocytes (% white blood count)20±7.622±7.620±7.521±7.0<0.00119±7.320±7.420±7.323±7.70.003
  • COPD, chronic obstructive pulmonary disease; BMI, body mass index; nPCR, normalized protein catabolic rate; TIBC, total iron-binding capacity; PTH, parathyroid hormone.

  • a Median and 25th and 75th percentiles presented instead of mean, because the predictor was not normally distributed.