Ignite Creation Date:
2024-05-05 @ 11:08 AM
Last Modification Date:
2024-10-26 @ 9:05 AM
Study NCT ID:
NCT00005362
Status:
COMPLETED
Last Update Posted:
2016-05-13
First Post:
2000-05-25
Brief Title:
Dose Estimation for Studies of Acute Respiratory Effects
Sponsor:
National Heart Lung and Blood Institute NHLBI
Organization:
National Heart Lung and Blood Institute NHLBI
Study Overview
Official Title:
None
Status:
COMPLETED
Status Verified Date:
2000-05
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
To modify and expand an existing pharmacokinetic model for nasal dose as well as to develop a new model to estimate tracheobronchial dose of an active agent for each subject in a study of acute respiratory health effects
Detailed Description:
BACKGROUND
Epidemiologic analysis of acute reversible respiratory health effects is uncommonly performed yet these are important health outcomes because acute responses by the respiratory defense system appear to represent one end of the continuum toward progressive chronic and potentially disabling physiologic changes Repeatable epidemiologic studies of dose-response relationships necessitate accurate measures of dose However in occupational and environmental settings exposure to a toxin is seldom found at identical concentrations andor particle sizes among persons with the same activity patterns In addition air concentration does not account for factors such as clearance or metabolism which may alter the biologically effective tissue dose These factors cause the target tissue dose of the toxin to vary greatly despite exposure to similar air concentrations
DESIGN NARRATIVE
The results of these toxicokinetic models were individual measures of tissue dose used in a 2-stage epidemiologic analysis which placed special emphasis on the definition of individual dose-response curves for exposure to an irritant dust sodium borate and the reversible effects of peak expiratory flow and irritant symptoms A primary advantage of the two stage epidemiologic approach was that it permitted particular attention to be focused on the factors which determined the sensitivity threshold and reactivity slope for an individual The use of tissue dose estimates were also compared to simple exposure measurements in the epidemiologic analysis to evaluate the efficacy of using dosimetric methods in epidemiologic studies
The study completion date listed in this record was obtained from the End Date entered in the Protocol Registration and Results System PRS record
Epidemiologic analysis of acute reversible respiratory health effects is uncommonly performed yet these are important health outcomes because acute responses by the respiratory defense system appear to represent one end of the continuum toward progressive chronic and potentially disabling physiologic changes Repeatable epidemiologic studies of dose-response relationships necessitate accurate measures of dose However in occupational and environmental settings exposure to a toxin is seldom found at identical concentrations andor particle sizes among persons with the same activity patterns In addition air concentration does not account for factors such as clearance or metabolism which may alter the biologically effective tissue dose These factors cause the target tissue dose of the toxin to vary greatly despite exposure to similar air concentrations
DESIGN NARRATIVE
The results of these toxicokinetic models were individual measures of tissue dose used in a 2-stage epidemiologic analysis which placed special emphasis on the definition of individual dose-response curves for exposure to an irritant dust sodium borate and the reversible effects of peak expiratory flow and irritant symptoms A primary advantage of the two stage epidemiologic approach was that it permitted particular attention to be focused on the factors which determined the sensitivity threshold and reactivity slope for an individual The use of tissue dose estimates were also compared to simple exposure measurements in the epidemiologic analysis to evaluate the efficacy of using dosimetric methods in epidemiologic studies
The study completion date listed in this record was obtained from the End Date entered in the Protocol Registration and Results System PRS record
Study Oversight
Has Oversight DMC:
Is a FDA Regulated Drug?:
Is a FDA Regulated Device?:
Is an Unapproved Device?:
Is a PPSD?:
Is a US Export?:
Is an FDA AA801 Violation?:
Secondary IDs
| Secondary ID | Type | Domain | Link |
|---|---|---|---|
| R01HL048853 | NIH | None | httpsreporternihgovquickSearchR01HL048853 |