Transcript Knowledge and Attitudes Toward Genetic Testing in

Knowledge and Attitudes Toward
Genetic Testing in Parkinson’s
Disease
Dana Lundberg
2006
Parkinson’s Disease
• Is a degenerative neurological disorder
• Affects the substantia nigra, the part of
the brain that controls movement
• Includes three symptoms:
a resting tremor
rigidity
bradykinesia (slowness)
Substantia Nigra
www.nlm.nih.gov/medlineplus/enc
y/imagepages/19515.htm
Onset Categories
• Parkinson’s disease is divided into two
onset categories:
Young-onset (less than 50 years at onset)
Old-onset (50 years or older at onset)
Objectives
• To identify attitudes Parkinson’s disease patients
have toward diagnostic, predictive, and prenatal
genetic testing
• To identify the resources most used by patients for
information on Parkinson’s disease
• To assess the level of knowledge patients have about
the genetics of Parkinson’s disease
Genetics of Parkinson’s
• Studies by Healy et al. (2004), Toft et al. (2005), and
Hattori et al. (2004) revealed several gene mutations
• Genes that mutations have been identified in:
- parkin
- PINK1
- DJ-1
- α-Synuclein
- LRKK2
• Clinical genetic testing for the parkin and PINK1 genes is
available
Rationale
• Prior to wide spread use of genetic testing for Parkinson’s
disease researchers need to be aware of:
 The interest level in genetic testing
 The level of knowledge patients have of genetic testing
Where to target educational programs for genetic testing
Background
• Jacobs et al. showed attitudes toward genetic testing in a
young-onset Parkinson’s population:
72% of subjects indicated that they would take a
presymptomatic genetic test
57% were interested in the availability of a prenatal
genetic test for Parkinson’s
• My study differs:
It included both young and old-onset patients
It included questions regarding sources of information and
knowledge about the genetics of Parkinson’s
Hypothesis
Patients with Parkinson’s disease will respond with a
positive attitude toward diagnostic, predictive, and prenatal
genetic testing for the disease.
Survey Sites
• Struthers Parkinson’s Center (n = 58)
• National Parkinson Foundation’s Young-Onset Conference
in Phoenix, AZ (n = 39)
Struthers Parkinson’s
Center (Golden Valley, MN)
Young-Onset Parkinson’s
Conference (Phoenix, AZ)
Survey
• Demographics
• General knowledge about:
 Parkinson’s disease
 genetics
 genetics of Parkinson’s disease
• Sources of information on Parkinson’s disease
• Attitudes toward:
 diagnostic genetic testing
 predictive genetic testing
prenatal genetic testing
 genetic testing at 100%, 90%, and 60% genetic risk
Data Analysis
• Data were tabulated in an Excel spreadsheet
• Data were analyzed using descriptive and nonlinear
(chi-squared) statistics
• P-values were considered significant when p ≤ 0.050
Distribution of Age of Onset
onset < 50 years
53%
47%
onset ≥ 50 years
Distribution of Gender
42%
58%
Male
Female
Education Levels of Subject
Population
19%
High school
65%
16%
Technical training or
some college
College graduate or
higher
Distribution of Subjects with Relatives
Diagnosed with Parkinson’s
21%
none
≥1
79%
Sources
Primary Care Doctor
40
Radio/TV
Friends/Family
Physical/
Occupational/Speech
Nurse
Internet
Support/ Conference/
Edu. programs
45
Lay organizations
Books/ magazines
Neurologist
Number of subjects
Sources of Information
50
P<0.001
< 50 years at onset
≥ 50 years at onset
35
30
25
20
15
10
5
0
Sources
Primary Care Doctor
40
Radio/TV
Friends/Family
Physical/
Occupational/Speech
Nurse
Internet
45
Support/ Conference/
Edu. programs
Lay organizations
Books/ magazines
Neurologist
Number of subjects
Sources of Information
50
P<0.001
< 50 years at onset
≥ 50 years at onset
35
30
25
20
15
10
5
0
Sources
Primary Care Doctor
40
Radio/TV
Friends/Family
Physical/
Occupational/Speech
Nurse
45
Internet
Support/ Conference/
Edu. programs
Lay organizations
Books/ magazines
Neurologist
Number of subjects
Sources of Information
50
P<0.001
< 50 years at onset
≥ 50 years at onset
35
30
25
20
15
10
5
0
Sources
40
30
Primary Care Doctor
45
Radio/TV
Friends/Family
Physical/
Occupational/Speech
Nurse
Internet
Support/ Conference/
Edu. programs
Lay organizations
Books/ magazines
Neurologist
Number of subjects
Sources of Information
50
< 50 years at onset
≥ 50 years at onset
35
25
P=0.040
20
15
10
5
0
Knowledge about Parkinson's and genetics: Number answering correctly (%)
< 50
years at
onset
n (%)
≥ 50 years
at onset
n (%)
Total
(%)
p-value
Parkinson’s disease is less common in people who smoke.
16 (35%)
10 (20%)
27%
p = 0.090
Parkinson’s disease always begins after age 50.
45 (98%)
46 (90%)
94%
p = 0.120
Parkinson’s disease is caused by a problem in brain cells that use dopamine.
44 (96%)
44 (86%)
91%
p = 0.110
There is a gene therapy treatment that can cure Parkinson’s disease.
45 (98%)
47 (92%)
95%
p = 0.210
There is an over-the counter, “natural” treatment that can cure Parkinson’s
disease.
46 (100%)
48 (94%)
97%
p = 0.090
A gene is composed of a group of proteins.
9 (20%)
4 (8%)
13%
p = 0.090
Genetic diseases always begin in childhood.
39 (85%)
40 (78%)
81%
p = 0.440
43 (93%)
39 (76%)
85%
p = 0.020
Parkinson’s disease can be caused by a mutation in a gene called parkin.
16 (35%)
4 (8%)
21%
p < 0.001
Scientists have identified genes that are associated with a higher risk of
Parkinson’s disease.
30 (65%)
19 (37%)
51%
p = 0.005
Knowledge Questions:
Parkinson's Disease Knowledge Questions:
Specific Genetic Questions:
It is possible to have an abnormal gene without having symptoms of a
disease.
The Genetics of Parkinson's Disease Questions:
Knowledge about Parkinson's and genetics: Number answering correctly (%)
< 50
years at
onset
n (%)
≥ 50 years
at onset
n (%)
Total
(%)
p-value
Parkinson’s disease is less common in people who smoke.
16 (35%)
10 (20%)
27%
p = 0.090
Parkinson’s disease always begins after age 50.
45 (98%)
46 (90%)
94%
p = 0.120
Parkinson’s disease is caused by a problem in brain cells that use dopamine.
44 (96%)
44 (86%)
91%
p = 0.110
There is a gene therapy treatment that can cure Parkinson’s disease.
45 (98%)
47 (92%)
95%
p = 0.210
There is an over-the counter, “natural” treatment that can cure Parkinson’s disease.
46 (100%)
48 (94%)
97%
p = 0.090
A gene is composed of a group of proteins.
9 (20%)
4 (8%)
13%
p = 0.090
Genetic diseases always begin in childhood.
39 (85%)
40 (78%)
81%
p = 0.440
43 (93%)
39 (76%)
85%
p = 0.020
Parkinson’s disease can be caused by a mutation in a gene called parkin.
16 (35%)
4 (8%)
21%
p < 0.001
Scientists have identified genes that are associated with a higher risk of
Parkinson’s disease.
30 (65%)
19 (37%)
51%
p = 0.005
9 (20%)
16 (31%)
26%
p = 0.180
Knowledge Questions:
Parkinson's Disease Knowledge Questions:
Specific Genetic Questions:
It is possible to have an abnormal gene without having symptoms of a
disease.
The Genetics of Parkinson's Disease Questions:
There is a gene test that can identify who will get Parkinson’s disease.
Knowledge about Parkinson's and genetics: Number answering correctly (%)
< 50
years at
onset
n (%)
≥ 50 years
at onset
n (%)
Total
(%)
p-value
Parkinson’s disease is less common in people who smoke.
16 (35%)
10 (20%)
27%
p = 0.090
Parkinson’s disease always begins after age 50.
45 (98%)
46 (90%)
94%
p = 0.120
Parkinson’s disease is caused by a problem in brain cells that use dopamine.
44 (96%)
44 (86%)
91%
p = 0.110
There is a gene therapy treatment that can cure Parkinson’s disease.
45 (98%)
47 (92%)
95%
p = 0.210
There is an over-the counter, “natural” treatment that can cure Parkinson’s disease.
46 (100%)
48 (94%)
97%
p = 0.090
A gene is composed of a group of proteins.
9 (20%)
4 (8%)
13%
p = 0.090
Genetic diseases always begin in childhood.
39 (85%)
40 (78%)
81%
p = 0.440
43 (93%)
39 (76%)
85%
p = 0.020
Parkinson’s disease can be caused by a mutation in a gene called parkin.
16 (35%)
4 (8%)
21%
p < 0.001
Scientists have identified genes that are associated with a higher risk of
Parkinson’s disease.
30 (65%)
19 (37%)
51%
p = 0.005
9 (20%)
16 (31%)
26%
p = 0.180
Knowledge Questions:
Parkinson's Disease Knowledge Questions:
Specific Genetic Questions:
It is possible to have an abnormal gene without having symptoms of a
disease.
The Genetics of Parkinson's Disease Questions:
There is a gene test that can identify who will get Parkinson’s disease.
Attitudes toward Genetic Testing: Number answering "yes" (%)
< 50 years
at onset
n (%)
≥ 50 years
at onset
n (%)
Total
(%)
p-value
100% genetic risk
33 (72%)
44 (86%)
79%
p = 0.250
90% genetic risk
33 (72%)
41 (80%)
76%
p = 0.250
60% genetic risk
23 (50%)
34 (67%)
59%
p = 0.100
100% genetic risk
36 (78%)
34 (67%)
72%
p = 0.250
90% genetic risk
32 (70%)
25 (49%)
59%
p = 0.050
60% genetic risk
26 (57%)
25 (49%)
53%
p = 0.500
100% genetic risk
23 (50%)
17 (33%)
41%
p = 0.100
90% genetic risk
23 (50%)
15 (29%)
39%
p = 0.050
60% genetic risk
21 (46%)
13 (25%)
35%
p = 0.050
Questions
Diagnostic Genetic Testing: Would you take this test?
Predictive Genetic Testing: Do you think this genetic test
should be offered to people without symptoms of
Parkinson’s disease?
Prenatal Genetic Testing: Do you think a prenatal
genetic test should be offered to pregnant mothers?
Attitudes toward Genetic Testing: Number answering "yes" (%)
< 50 years
at onset
n (%)
≥ 50 years
at onset
n (%)
Total
(%)
p-value
100% genetic risk
33 (72%)
44 (86%)
79%
p = 0.250
90% genetic risk
33 (72%)
41 (80%)
76%
p = 0.250
60% genetic risk
23 (50%)
34 (67%)
59%
p = 0.100
100% genetic risk
36 (78%)
34 (67%)
72%
p = 0.250
90% genetic risk
32 (70%)
25 (49%)
59%
p = 0.050
60% genetic risk
26 (57%)
25 (49%)
53%
p = 0.500
100% genetic risk
23 (50%)
17 (33%)
41%
p = 0.100
90% genetic risk
23 (50%)
15 (29%)
39%
p = 0.050
60% genetic risk
21 (46%)
13 (25%)
35%
p = 0.050
Questions
Diagnostic Genetic Testing: Would you take this test?
Predictive Genetic Testing: Do you think this genetic test
should be offered to people without symptoms of
Parkinson’s disease?
Prenatal Genetic Testing: Do you think a prenatal
genetic test should be offered to pregnant mothers?
Attitudes toward Genetic Testing: Number answering "yes" (%)
< 50 years
at onset
n (%)
≥ 50 years
at onset
n (%)
Total
(%)
p-value
100% genetic risk
33 (72%)
44 (86%)
79%
p = 0.250
90% genetic risk
33 (72%)
41 (80%)
76%
p = 0.250
60% genetic risk
23 (50%)
34 (67%)
59%
p = 0.100
100% genetic risk
36 (78%)
34 (67%)
72%
p = 0.250
90% genetic risk
32 (70%)
25 (49%)
59%
p = 0.050
60% genetic risk
26 (57%)
25 (49%)
53%
p = 0.500
100% genetic risk
23 (50%)
17 (33%)
41%
p = 0.100
90% genetic risk
23 (50%)
15 (29%)
39%
p = 0.050
60% genetic risk
21 (46%)
13 (25%)
35%
p = 0.050
Questions
Diagnostic Genetic Testing: Would you take this test?
Predictive Genetic Testing: Do you think this genetic test
should be offered to people without symptoms of
Parkinson’s disease?
Prenatal Genetic Testing: Do you think a prenatal
genetic test should be offered to pregnant mothers?
Discussion
 Overall the attitudes expressed towards diagnostic,
predictive, and prenatal genetic testing were positive
1. A majority (≥ 50%) of patients expressed positive attitudes
toward diagnostic genetic testing at all three levels of genetic
risk
2. Young-onset patients expressed positive attitudes toward
predictive genetic testing slightly more, but not significantly
more, than old-onset patients at all three levels of genetic risk
3. Young-onset patients expressed positive attitudes toward
prenatal genetic testing significantly more than old-onset at
the 90% and 60% levels of genetic risk (p = 0.050 for both
tests)
Discussion
 Most commonly used source of information was a neurologist
 Young-onset subjects used the internet significantly more than
old-onset (p < 0.001)
 Young-onset subjects used lay organizations and support
groups/conferences significantly more than the old-onset
subjects (p < 0.001 for both resources)
 a majority of the young-onset subjects were interviewed at a
National Parkinson Foundation conference
 Young-onset subjects were significantly more knowledgeable
about the genetics of Parkinson’s (p < 0.001 and p = 0.005)
 Number of patients that correctly answered questions in both
the young-onset and, especially, the old-onset groups was low
Applications
• Educational programmers:
 What aspects of Parkinson’s and genetics to focus
programs
 Where to publish information to best educate the
Parkinson’s community about genetic testing
• Pharmaceutical companies:
 What populations to target for genetic testing
 At what levels of genetic risk patients may be interested in
taking genetic tests
Future Work
• Larger subject population through a mailed survey
• Redesign survey to include reasons for accepting or
rejecting genetic testing
• Conduct at a conference oriented toward old-onset or both
onset groups
Acknowledgements
•
•
•
•
Dr. Martha Nance
Catherine Wielinski
Ms. Fruen
2005-06 Research Team
Knowledge and Attitudes
Toward Genetic Testing in
Parkinson’s Disease
Dana Lundberg
2006