Cancer and Amyotrophic Lateral Sclerosis in Livingston County, Illinois
A Report Commissioned by the Livingston County Environmental Association
Peter P. Moschovis and Leslie Stayner, PhD
University of Illinois at Chicago
School of Public Health
May 11, 2006
Background
In 2004, UIC’s Department of Epidemiology was approached by the LCEA, a citizens’ group
concerned about a possible cluster of disease, concerned that local environmental exposures may
be causing an excess of cancer and amyotrophic lateral sclerosis (ALS). As a first step toward
addressing these concerns, we were asked to determine whether there is in fact an elevated rate
of these diseases in Livingston County. In particular, the study was designed to answer the
following questions:
 What is the absolute risk of death by cancer type in Livingston County?
 What is the relative risk of death by cancer type, comparing Livingston County to the
state of Illinois?
 What are the most common cancers in Livingston County?
 What is known about the risk factors for those cancers?
 What is the risk of dying of ALS in Livingston County?
 Does the risk of ALS differ significantly from the rate for Illinois or the U.S. as a whole?
Methods
Using the public data files of the Illinois State Cancer Registry for the years 1988 – 2002, we
calculated age, sex, and race-specific rates and relative risks for 24 categories of cancer. In
addition, we calculated age-adjusted death rates and relative risks for ALS using the Compressed
Mortality File provided by the National Center for Health Statistics. Population estimates for
each county were provided by the IDPH and based on US Census Intercensal Population
Estimates.
Results
Cancer
During the period 1988 – 2002, 825,196 cases of cancer were reported in Illinois, of which 3,045
cases of cancer were reported in Livingston County. For all cancer sites during this period,
comparing Livingston County to Illinois, the crude relative risk for cancer is 1.12 [95% CI =
1.076, 1.156], p < 0.001. After adjusting for age, sex, and race, the adjusted relative risk is 0.963
[0.930, 0.998], p = 0.0391.
Twenty four cancer types were examined in the ISCR dataset. Of those, the majority were
equally common in Livingston County and the state of Illinois (lung, NHL, HL, endometrial,
melanoma, kidney, oral cavity, pancreas, ovarian, stomach, CNS, cervical, esophageal, and
testicular cancer), four were less common in Livingston County (invasive and in situ breast,
liver, prostate, and colorectal cancer), and four were more common in Livingston County
(bladder, leukemia, myeloma, and bone cancer). Figure 1 summarizes the adjusted relative risks
for each of the cancer types, and Table 3 summarizes the absolute, crude, and adjusted relative
risks of each cancer type studied for Livingston County and Illinois.
1
ALS
During the period 1979 – 2002, there were 18 ALS deaths in Livingston County, yielding a crude
death rate of 1.874 per 100,000 persons and an age-adjusted death rate of 1.607 per 100,000
persons (see Table 1). All ALS deaths observed were in individuals age 45 or older.
Number of Deaths
Livingston County
Illinois
USA
18
3,969
90,934
Total Population
Crude
Death Rate
960,390
282,587,493
6,095,041,280
Age-adjusted
Death Rate*
1.874
1.405
1.492
1.607
1.420
1.491
Table 1: Total ALS Deaths in Livingston County, Illinois, and USA from 1979 – 2002.
* Age-Adjusted to the 1990 US population
While the rate of ALS appears marginally greater in Livingston County, when formally
compared with the state and the country, no significant difference was observed (see Table 2).
Comparison Groups
Livingston County vs.
Illinois
Livingston County vs.
USA
Age-adjusted Relative
Risk*
95% Confidence Interval
P
1.1316
(0.6550, 1.9551)
0.6574
1.0778
(0.6243, 1.8605)
0.7880
Table 2: Age-adjusted relative risks for ALS Deaths in Livingston County vs. Illinois and USA from 1979 – 2002
* Age-Adjusted to the 1990 US population
Discussion
The cancer study revealed that as a whole, cancer appears to be equally likely in Livingston
County and in Illinois. The majority of cancer cases were caused by the four most common
cancers (lung, breast, prostate, and colon). Undoubtedly, prevention and early detection of these
cancers is the most effective method of reducing the burden of cancer in Livingston County.
Most of the cancers studied were equally common in Livingston County and the rest of the state;
a few were less and a few were more common in Livingston County. In particular, the risk of
bone cancer is almost two-fold greater in Livingston County than in the rest of the state. While
this only represents 10 cases over the 15-year period studied, the excess of this rare cancer may
merit further investigation.
With respect to ALS, there is no evidence of an excess risk of ALS death in Livingston County
compared to either Illinois or the nation.
This study has several major limitations. First, the limited number of cancer categories in the
ISCR does not allow the detection of differences in rare cancers. Second, the lack of geographic
information for either ALS or cancer makes assessment of spatial association with any
environmental exposure impossible. Finally, the small population of Livingston County gives
relatively low statistical power to detect subtle differences over time or among rare diseases.
2
0.00
0.50
1.00
1.50
2.00
Lung
breast-invasive
prostate
colorectal
all other sites
bladder
NHL
leukemias
endometrial
melanoma
kidney
oral cavity
pancreas
ovary
breast - in situ
myelomas
stomach
nervous system
cervix - invasive
esophagus
Hodgkin’s lymphomas
testis
liver
bone
Figure 1
Adjusted Relative Risk (adjusted for age, sex, and race) of cancer incidence for Livingston County vs. Illinois
Livingston County
Cases per
Cases
100,000
Lung
breast-invasive
prostate
colorectal
all other sites
bladder
NHL
leukemias
endometrial
melanoma
kidney
oral cavity
457
424
378
368
281
181
114
112
96
81
67
66
76.87
71.31
63.58
61.90
47.26
30.44
19.17
18.84
16.15
13.62
11.27
11.10
Illinois
Cases per
Cases
100,000 Crude RR
121758
123143
110890
102729
75342
36489
30662
20701
23688
17067
20323
18310
67.75
68.52
61.71
57.16
41.92
20.30
17.06
11.52
13.18
9.50
11.31
10.19
1.13
1.04
1.03
1.08
1.13
1.50
1.12
1.64
1.22
1.43
1.00
1.09
Adjusted
RR (MH)*
0.98
0.91
0.89
0.90
0.99
1.17
0.93
1.37
1.04
1.19
0.86
1.00
3
95
(0
(0
(0
(0
(0
(1
(0
(1
(0
(0
(0
(0
pancreas
ovary
breast - in situ
myelomas
stomach
nervous system
cervix - invasive
esophagus
Hodgkin’s lymphomas
testis
liver
bone
58
58
49
46
43
41
35
29
21
19
11
10
9.76
9.76
8.24
7.74
7.23
6.90
5.89
4.88
3.53
3.20
1.85
1.68
19005
13962
19618
9464
14353
11134
10532
9036
5059
4374
6076
1481
10.58
7.77
10.92
5.27
7.99
6.20
5.86
5.03
2.82
2.43
3.38
0.82
0.92
1.26
0.75
1.47
0.91
1.11
1.00
0.97
1.25
1.31
0.55
2.04
0.79
1.08
0.68
1.38
0.83
0.97
1.09
0.92
1.21
1.25
0.52
1.91
Table 3: Absolute, Crude, and Adjusted Relative Risks of cancer in Livingston County and Illinois
between 1988 and 2002
* RR adjusted for age, sex, and race
4
(0
(0
(0
(1
(0
(0
(0
(0
(0
(0
(0
(1