Skip to main content

Table 1 Characteristics of study population and between-group comparison; USRDS 2006–2008

From: Association of restless legs syndrome and mortality in end-stage renal disease: an analysis of the United States Renal Data System (USRDS)

Variable

Total n = 279,956

RLS n = 372

NSD n = 279,584

P

Incidence age, years

62.05 ± 15.39

64.22 ± 15.64

62.04 ± 15.39

0.007

Gender

   

0.2

 Female

43.72 (122,400)

47.3 (176)

43.7 (122,224)

 

 Male

56.28 (157,556)

52.7 (196)

56.3 (157,360)

 

Race

   

<.0001

 White

64.38 (180,239)

86.29 (321)

64.35 (179,918)

 

 Black

29.93 (83,782)

11.56 (43)

29.95 (83,739)

 

 Asian

3.32 (9282)

1.34 (5)

3.32 (9277)

 

 Native American

1.08 (3026)

0.27 (1)

1.08 (3025)

 

 Other/Unknown

1.3 (3627)

0.54 (2)

1.3 (3625)

 

Ethnicity

   

0.002

 Non-Hispanic/Latino

85.68 (239,880)

91.4 (340)

85.68 (239,540)

 

 Hispanic/Latino

14.32 (40,076)

8.6 (32)

14.32 (40,044)

 

Vascular access type

   

0.0002

 AV Fistula

14.61 (40,902)

23.12 (86)

14.6 (40,816)

 

 Graft

3.95 (11,058)

4.3 (16)

3.95 (11,042)

 

 Catheter

80.28 (224,739)

71.77 (267)

80.29 (224,472)

 

 Other/Unknown

1.16 (3257)

0.81 (3)

1.16 (3254)

 

Body mass index (kg/m2)f

28.74 ± 7.71

28.98 ± 7.57

28.74 ± 7.71

0.5

Serum creatinine (mg/dl)f

6.58 ± 3.46

6.64 ± 3.74

6.58 ± 3.46

0.8

Serum albumin (g/dl)f

3.11 ± 0.71

3.32 ± 0.64

3.11 ± 0.71

<.0001

Anemiaa

8.37 (23,432)

11.83 (44)

8.37 (23,388)

0.02

Cardiovascular

 Coronary artery diseaseb

21.09 (59,054)

17.2 (64)

21.1 (58,990)

0.07

 Congestive heart failure

32.18 (90,088)

26.34 (98)

32.19 (89,990)

0.02

 Cerebrovascular disease

9.4 (26,329)

8.06 (30)

9.41 (26,299)

0.4

 Peripheral vascular disease

14.04 (39,301)

10.22 (38)

14.04 (39,263)

0.03

 Hypertension

84.92 (237,737)

83.6 (311)

84.92 (237,426)

0.5

Other

 Diabetes

52.78 (147,771)

38.98 (145)

52.8 (147,626)

<.0001

 Cancer

6.81 (19,065)

5.91 (22)

6.81 (19,043)

0.5

Sleep disorders

 Any sleep disorder

0.13 (372)

100.0 (372)

0 (0)

<.0001

 Restless legs syndrome

0.13 (372)

100.0 (372)

0 (0)

<.0001

 Obstructive sleep apnea

0.01 (17)

4.57 (17)

0 (0)

<.0001

Psychological disorders

 Major depressive disorder

0.37 (1030)

1.61 (6)

0.37 (1024)

<.0001

 Dysthymic disorder

0.26 (727)

2.15 (8)

0.26 (719)

<.0001

 Anxiety

0.6 (1691)

4.03 (15)

0.6 (1676)

<.0001

 Adjustment disorder

0.03 (81)

0.27 (1)

0.03 (80)

0.1

 Depressionc

0.65 (1829)

4.03 (15)

0.65 (1814)

<.0001

 Minor depressive disorderd

0.29 (808)

2.42 (9)

0.29 (799)

<.0001

 Psychological disordere

1.24 (3459)

8.06 (30)

1.23 (3429)

<.0001

Tobacco dependence

6.39 (17,887)

8.87 (33)

6.39 (17,854)

0.05

Alcohol dependence

1.57 (4384)

0.81 (3)

1.57 (4381)

0.2

Drug dependence

1.55 (4339)

1.08 (4)

1.55 (4335)

0.5

  1. Age and clinical measures are mean ± SD. Categorical data are percentages (counts). No sleep disorder diagnosed (NSD)
  2. aDetermined by ICD-9-CM codes 280.0–280.9, 285.0, 285.2, 285.8, 285.9
  3. bAtherosclerosis, myocardial infarction (MI), ischemic heart disease (IHD)
  4. cmajor depressive disorder, dysthymic disorder, adjustment disorder
  5. dDysthymic disorder, adjustment disorder
  6. eDepression, anxiety
  7. fMissing data points
Back to article page

BMC Nephrology

ISSN: 1471-2369

Contact us