Occupational risk and chronic kidney disease: a population-based study in the United States adult population

Figures & data

Table 1 Description of risk factors for chronic kidney disease outcome among employed Americans aged 18 to 70 years (N = 91,340)*, from the National Health Interview Survey, 2004 to 2008

Variable	^Table Footnote‡ N (%)	^Table Footnote† N (%) of CKD	OR	CI
Female	48,485 (53.1)	659 (1.4)
Age
18–30	22,062 (25.8)	144 (0.7)	1.00
31–40	18,321 (21.4)	160 (0.9)	1.34	1.07, 1.68
41–50	18,724 (21.9)	236 (1.3)	1.94	1.58, 2.39
51–60	15,546 (18.2)	275 (1.8)	2.74	2.24, 3.36
61–70	10,816 (12.7)	291 (2.7)	4.21	3.44, 5.15
Occupation
Life, Physical, and Social Science Occupations	786 (0.9)	2 (0.3)	1.00
Management Occupations	7311 (8)	66 (0.9)	3.57	0.87, 14.6
Healthcare Practitioners and Technical Occupations	4131 (4.5)	40 (1.0)	3.83	0.92, 15.9
Healthcare Support Occupations	2592 (2.8)	58 (2.2)	8.97	2.19, 36.8
Protective Service Occupations	1794 (2)	22 (1.2)	4.86	1.14, 20.7
Food Preparation and Serving Related Occupations	5063 (5.5)	91 (1.8)	7.17	1.76, 29.2
Building and Grounds Cleaning and Maintenance Occupations	4476 (4.9)	98 (2.2)	8.77	2.16, 35.6
Personal Care and Service Occupations	3084 (3.4)	51 (1.7)	6.59	1.6, 27.1
Sales and Related Occupations	9640 (10.6)	118 (1.2)	4.86	1.2, 19.7
Office and Administrative Support Occupations	13,297 (14.6)	141 (1.1)	4.20	1.04, 17
Farming, Fishing, and Forestry Occupations	836 (0.9)	16 (1.9)	7.64	1.75, 33.3
Construction and Extraction Occupations	5649 (6.2)	59 (1.0)	4.14	1.01, 17
Business and Financial Operations Occupations	3511 (3.8)	35 (1.0)	3.95	0.95, 16.4
Installation, Maintenance, and Repair Occupations	3036 (3.3)	35 (1.2)	4.57	1.1, 19
Production Occupations	7423 (8.1)	142 (1.9)	7.64	1.89, 30.9
Transportation and Material Moving Occupations	5690 (6.2)	114 (2.0)	8.01	1.98, 32.5
Military Specific Occupations	222 (0.2)	1 (0.5)	1.77	0.16, 19.6
Computer and Mathematical Occupations	1773 (1.9)	16 (0.9)	3.57	0.82, 15.5
Architecture and Engineering Occupations	1404 (1.5)	12 (0.9)	3.38	0.75, 15.1
Community and Social Services Occupations	14,80 (1.6)	11 (0.7)	2.93	0.65, 13.3
Legal Occupations	897 (1)	8 (0.9)	3.53	0.75, 16.6
Education, Training, and Library Occupations	5576 (6.1)	51 (0.9)	3.62	0.88, 14.9
Arts, Design, Entertainment, Sports and Media Occupations	1669 (1.8)	10 (0.6)	2.36	0.52, 10.8
Hypertension	18370 (20.1)	705 (3.8)	5.94	5.29, 6.68
Race
White	75,778 (83)	891 (1.2)	0.59	0.52, 0.68
Black/African American	15,562 (17)	306 (2.0)	1.00
Education
Did not finish high school	16,635 (18.3)	406 (2.4)	1.00
Completed high school	22,635 (24.9)	302 (1.3)	0.54	0.46, 0.63
Some college or technical school	28,212 (31)	322 (1.1)	0.46	0.4, 0.53
Completed college	15,685 (17.3)	111 (0.7)	0.28	0.23, 0.35
Some graduate training after college	7737 (8.5)	48 (0.6)	0.25	0.18, 0.34
Total earnings last year
$01–$4,999	4406 (7.5)	61 (1.4)	1.00
$5,000–$9,999	4229 (7.2)	49 (1.2)	0.83	0.57, 1.22
$10,000–$14,999	5350 (9.1)	64 (1.2)	0.86	0.61, 1.23
$15,000–$19,999	5068 (8.6)	56 (1.1)	0.80	0.55, 1.15
$20,000–$24,999	5728 (9.7)	42 (0.7)	0.53	0.35, 0.78
$25,000–$34,999	9671 (16.5)	62 (0.6)	0.46	0.32, 0.66
$35,000–$44,999	7730 (13.2)	50 (0.7)	0.46	0.32, 0.68
$45,000–$54,999	5489 (9.3)	33 (0.6)	0.43	0.28, 0.66
$55,000–$64,999	3340 (5.7)	14 (0.4)	0.30	0.17, 0.54
$65,000–$74,999	2238 (3.8)	10 (0.5)	0.32	0.16, 0.63
$75,000 and over	5512 (9.4)	25 (0.5)	0.32	0.2, 0.52
Ever been told you had coronary heart disease	2534 (2.8)	200 (7.9)	7.63	6.52, 8.93
Ever been told you had a stroke	1512 (1.7)	134 (8.9)	8.14	6.75 9.82
Ever told you have diabetes
No	84,462 (92.5)	770 (0.9)	1.00
Borderline	820 (0.9)	33 (4.0)	4.56	3.19, 6.5
Yes	6024 (6.6)	392 (6.5)	7.57	6.68, 8.57
Smoking status
Never smoker	51,846 (57.2)	558 (1.1)	1.00
Current every day smoker	16,717 (18.4)	265 (1.6)	1.48	1.28, 1.72
Current someday smoker	4556 (5)	70 (1.5)	1.43	1.12, 1.84
Former smoker	17,508 (19.3)	293 (1.7)	1.56	1.36, 1.8
BMI
BMI < 30	63,545 (72.3)	714 (1.1)	1.00
40 > BMI ≥ 30	20,733 (23.6)	346 (1.7)	1.49	1.31, 1.7
BMI ≥ 40	3659 (4.2)	93 (2.5)	2.30	1.85, 2.86
Chronic kidney disease	1197 (1.3)	1197 (100)

Notes:

* Cases were defined as subjects with physician-diagnosed weak/failing kidneys in the past 12 months, whereas control subjects had no weak/failing kidneys in the past 12 months. All variables except sex and chronic kidney disease were statistically significant different between two ethnicity groups, P-value < 0.05.

^‡Number of subjects (percent of total).

^†Number of subjects with weak/failing kidneys in past 12 months (percent of number of subjects). Numbers might not add up due to missing values. Percentages are reported among nonmissing observations.

Abbreviations: CKD, chronic kidney disease; OR, odds ratio; CI, confidence ratio.

Table 2 The association between occupation and weak/failing kidneys in the past 12 months, with weight given to underrepresented populations^*,§,‖

Occupation	OR	^‡ CI	^†Pr > Chi-Square
Military Specific Occupations	0.93	0.09, 10.2	0.9539
Installation, Maintenance, and Repair Occupations	2.54	0.6, 10.7	0.2047
Community and Social Services Occupations	2.85	0.62, 13	0.1770
Architecture and Engineering Occupations	2.92	0.64, 13.3	0.1661
Arts, Design, Entertainment, Sports and Media Occupations	3.26	0.71, 15	0.1292
Office and Administrative Support Occupations	3.28	0.8, 13.5	0.1002
Protective Service Occupations	3.34	0.9, 12.4	0.0711
Construction and Extraction Occupations	3.39	0.85, 13.6	0.0849
Business and Financial Operations Occupations	3.47	0.83, 14.4	0.0877
Management Occupations	3.51	0.86, 14.2	0.0792
Farming, Fishing, and Forestry Occupations	3.59	0.78, 16.5	0.1003
Sales and Related Occupations	3.88	0.99, 15.2	0.0522
Education, Training, and Library Occupations	3.96	0.97, 16.1	0.0550
Personal Care and Service Occupations	3.98	0.99, 16	0.0519
Building and Grounds Cleaning and Maintenance Occupations	4.32	1.06, 17.7	0.0415
Healthcare Practitioners and Technical Occupations	4.38	1.05, 18.2	0.0420
Transportation and Material Moving Occupations	4.72	1.17, 19.0	0.0290
Computer and Mathematical Occupations	4.74	1.08, 20.7	0.0389
Production Occupations	4.79	1.17, 19.7	0.0297
Food Preparation and Serving Related Occupations	5.29	1.34, 20.8	0.0172
Healthcare Support Occupations	6.08	1.46, 25.3	0.0131
Legal Occupations	6.14	1.24, 30.3	0.0258

Notes:

* Models were adjusted for age, sex, ethnicity, hypertension status, and education. Cases were defined as subjects with physician-diagnosed weak/failing kidneys in the past 12 months, whereas control subjects had no weak/failing kidneys in the past 12 months.

§ The table is ordered by odds ratio. There were 5660 observations with cancer that were removed from the total 97,000 observations.

‖ The rates were weighted to reflect the percentage in the US population, despite being taken from a sample. Consideration was taken and weight given to underrepresented populations. The calculation followed an algorithm that was developed based on the comparison of the study population with US census 2000 data.

‡ 95% Wald confidence interval. Reference group: Life, Physical, and Social Science occupations (because it had the lowest rate of weak/failing kidneys in the past 12 months).

† Chi-square probability was calculated from maximum likelihood estimation.

Abbreviations: OR, odds ratio; CI, confidence interval.