Parkinson's DiseaseNCT00044590
Parkinson's Diseases Susceptibility Genes and Pesticides
An observational study of Parkinson's Disease, run by National Institute of Environmental Health Sciences (NIEHS) at 1 site in United States.
Trial summary
Parkinson's disease (PD) occurrence is higher in rural than in urban populations of industrialized countries. Epidemiologic and human tissue studies suggest that pesticides may be responsible for causing dopaminergic cell death at increased rates. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Parkinson's Disease
- How many people
- 1,870 participants
- Where
- 1 siteUnited States
- Study dates
- 1 Sep 2000to 30 Nov 2016
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Study population: Our case population consists of patients with newly diagnosed idiopathic Parkinson's disease living in central California; they will be patients who have elicited care from health care providers. Controls will be randomly selected from Medicare records and matched to cases according to age, race, and sex.
Case population inclusion criteria:
- first Parkinson's disease (PD) diagnosis after January 1998
- currently living in one of the three target counties (Kern, Tulare, Fresno)
- have lived in California for at least 5 years
Case population exclusion criteria:
- have not been diagnosed with idiopathic PD
- first PD diagnosis before January 1998
- currently living outside of Kern, Tulare, or Fresno counties
- have lived in California for fewer than 5 years
Control population inclusion criteria:
- have never been diagnosed with PD
- currently living in one of the three target counties (Kern, Tulare, Fresno)
- have lived in California for at least 5 years
Control population exclusion criteria:
- have been diagnosed with PD
- currently living outside of Kern, Tulare, or Fresno counties
- have lived in California for fewer than 5 years
For each patient, one or more unaffected sibling controls and one population control will be recruited. The population control are being selected randomly from Medicare records (95% of all controls) and residential parcel listings (for those patients younger than 65 years of age only). The controls are being marginally matched to cases according to 5-year age categories (e.g. 50-54, 55-59, 60-64, etc.), race (white, African-American, Asian, Hispanic, other), and sex. All study cases by definition will be patients who elicited care from health care providers. We are aiming to enroll every newly diagnosed PD patient into our study and expect patient population participating in our study that is as diverse as the rural population.
Trial locations and contacts
1 site in 1 country.
United States1 site
Beate Ritz, UCLA Department of Epidemiology
Los Angeles, California, 90095-1772
About this study
Parkinson's disease (PD) occurrence is higher in rural than in urban populations of industrialized countries. Epidemiologic and human tissue studies suggest that pesticides may be responsible for causing dopaminergic cell death at increased rates. While many pathophysiologic pathways may be involved in the neurodegeneration responsible for PD, genetic factors are likely to determine a general susceptibility to neurodegeneration.
Read the detailed description
While many pathophysiologic pathways may be involved in the neurodegeneration responsible for PD, genetic factors are likely to determine a general susceptibility to neurodegeneration. There are a number of genetic polymorphisms of genes such as those coding for the cytochrome p450 super-family of genes referred to as 'susceptibility genes'. However, they are generally not sufficient to cause disease unless a person encounters exposure to an environmental toxin: the disease is caused by a gene-environment interaction. Thus, it is imperative to assess genetic susceptibility in individuals exposed to a toxin. We will test the gene-environment interaction hypothesis by conducting an epidemiologic population-based case-control study of newly diagnosed PD patients from three rural California counties: Kern, Fresno, and Tulare. Over a four year period, we expect to collect 400 cases referred to us by local neurologists, farm worker clinics, and Parkinson's foundations. For each case, one population control will be selected at random from residential parcel maps and Medicare databases and, in addition, one unaffected sibling control and - when possible - affected siblings to avoid potential biases and inefficiencies inherent in the use of each type of control. For each study subject, an environmental and occupational pesticide exposure estimate will be derived using California pesticide-use reporting (PUR) data and information about pesticide application on crops in combination with crop patterns shown in satellite images and aerial photographs; in addition, extensive exposure interviews will be conducted with all study subjects. In a three-tiered approach to examine the effects of gene-environment interactions we will: 1) test for association (and linkage) of PD to selected loci associated with PD in earlier studies using multiallelic repeat markers and genotyping; 2) test for association using intragenic single nucleotide polymorphisms (SNPs) of 50 candidate genes arrayed to create "the PD array"; and 3) use future technical possibilities to screen for genome wide associations using array technology to scan 5,000-10,000 SNPs throughout the genome. Data analysis will employ hierarchical modeling procedures to take into account multiple comparison issues and to incorporate prior knowledge such as increased neurotoxicity due to the interaction of gene products and chemicals.
- Conditions
- Parkinson's Disease
- Keywords
- Parkinson's disease, Pesticides, Genetic susceptibility, Polymorphisms
- Medical subject headings
- Parkinson Disease, Genetic Predisposition to Disease
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Cases | Patients with Parkinson's Disease | |
| Controls | Controls, subjects without Parkinson's Disease |
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 Sep 2002 (estimated)
- Study start1 Sep 2000
- Primary completion30 Nov 2016
- Study completion30 Nov 2016
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Parkinson's DiseaseStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case-control
- Time perspective
- Other
- Enrolment
- 1,870 participants (actual)
Sponsor and investigators
- Lead sponsor
- National Institute of Environmental Health Sciences (NIEHS)
- Sponsor type
- US National Institutes of Health
- Collaborators
- University of California, Los Angeles
- Responsible party
- Principal investigator, Beate Ritz, University of California, Los Angeles
- Investigators
- Beate Ritz, MD, PhD, Principal investigator, UCLA Department of Epidemiology
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00044590
- Sponsor's protocol ID
- 10544-CP-001
- Status last verified
- May 2017
- First submitted
- 3 Sep 2002
- Last updated
- 16 May 2017
- Results posted
- No
- Data monitoring committee
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 16 May 2017. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Parkinson's Diseases Susceptibility Genes and Pesticides
- ClinicalTrials.gov ID
- NCT00044590
- Acronym / sponsor ID
- 10544-CP-001
- Conditions
- Parkinson's Disease
- Keywords
- Parkinson's disease, Pesticides, Genetic susceptibility, Polymorphisms
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 1,870 participants (actual)
- Lead sponsor
- National Institute of Environmental Health Sciences (NIEHS)US National Institutes of Health
- Collaborators
- University of California, Los Angeles
- Study start
- 1 Sep 2000 (actual)
- Primary completion
- 30 Nov 2016 (actual)
- Study completion
- 30 Nov 2016 (actual)
- First posted
- 5 Sep 2002 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Parkinson's disease (PD) occurrence is higher in rural than in urban populations of industrialized countries. Epidemiologic and human tissue studies suggest that pesticides may be responsible for causing dopaminergic cell death at increased rates. While many pathophysiologic pathways may be involved in the neurodegeneration responsible for PD, genetic factors are likely to determine a general susceptibility to neurodegeneration.
Detailed description
While many pathophysiologic pathways may be involved in the neurodegeneration responsible for PD, genetic factors are likely to determine a general susceptibility to neurodegeneration. There are a number of genetic polymorphisms of genes such as those coding for the cytochrome p450 super-family of genes referred to as 'susceptibility genes'. However, they are generally not sufficient to cause disease unless a person encounters exposure to an environmental toxin: the disease is caused by a gene-environment interaction. Thus, it is imperative to assess genetic susceptibility in individuals exposed to a toxin. We will test the gene-environment interaction hypothesis by conducting an epidemiologic population-based case-control study of newly diagnosed PD patients from three rural California counties: Kern, Fresno, and Tulare. Over a four year period, we expect to collect 400 cases referred to us by local neurologists, farm worker clinics, and Parkinson's foundations. For each case, one population control will be selected at random from residential parcel maps and Medicare databases and, in addition, one unaffected sibling control and - when possible - affected siblings to avoid potential biases and inefficiencies inherent in the use of each type of control. For each study subject, an environmental and occupational pesticide exposure estimate will be derived using California pesticide-use reporting (PUR) data and information about pesticide application on crops in combination with crop patterns shown in satellite images and aerial photographs; in addition, extensive exposure interviews will be conducted with all study subjects. In a three-tiered approach to examine the effects of gene-environment interactions we will: 1) test for association (and linkage) of PD to selected loci associated with PD in earlier studies using multiallelic repeat markers and genotyping; 2) test for association using intragenic single nucleotide polymorphisms (SNPs) of 50 candidate genes arrayed to create "the PD array"; and 3) use future technical possibilities to screen for genome wide associations using array technology to scan 5,000-10,000 SNPs throughout the genome. Data analysis will employ hierarchical modeling procedures to take into account multiple comparison issues and to incorporate prior knowledge such as increased neurotoxicity due to the interaction of gene products and chemicals.
Study design
- Observational model
- Case-control
- Time perspective
- Other
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Cases | – | –Patients with Parkinson's Disease |
| Controls | – | –Controls, subjects without Parkinson's Disease |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
- Study population
- Our case population consists of patients with newly diagnosed idiopathic Parkinson's disease living in central California; they will be patients who have elicited care from health care providers. Controls will be randomly selected from Medicare records and matched to cases according to age, race, and sex.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Not reported in the source record.
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 16 May 2017.
- Individual participant dataSharing planned: Undecided
Related trials for Parkinson's Disease
Enrolling by invitationObservational study
Early Molecular Biomarkers for Differentiating Parkinsonian Syndromes
PARKINSON DISEASE (Disorder), Atypical Parkinsonism
Active, not recruitingPhase 1/2
Clinical Safety and Efficacy of Umbilical Cord Mesenchymal Stromal Cells-derived Exosomes in Patients With Parkinson's Disease
Parkinson Disease (PD)
Active, not recruitingObservational study
Adaptive DBS to Offset STN Dysregulation During Exercise in PD
Parkinson Disease
Not yet recruiting
Compulsive Eating and Brain's Reward System in Different Pathologies
PARKINSON DISEASE (Disorder), Bipolar 1 Disorder
Not yet recruiting
Evaluating the Effect of the Zeen Mobility Device on Clinical Practicality, Safety, and Impact (Via Assessments of Walking, Standing Tolerance, Balance, Endurance, Effort, and Participation in Daily Tasks) in an Outpatient Rehabilitation Setting for Individuals With Mobility Impairments.
Stroke, Parkinson's Disease (PD)
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Beate Ritz, MD, PhD principal investigator
UCLA Department of Epidemiology
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Parkinson's Disease, run by National Institute of Environmental Health Sciences (NIEHS) at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 16 May 2017. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 16 May 2017.