Study for Promotion of Health in Recycling Lead

Occupational Exposure Clinical Trial

— SPHERL  

Official title:

Study for Promotion of Health in Recycling Lead

Clinical Trial Details — Status: Active, not recruiting

Administrative data

• NCT number: NCT02243904
• Other study ID #: SPHERL
• Status: Active, not recruiting
• Start date: August 2015
• Est. completion date: December 31, 2024

Study information

• Verified date: March 2020
• Source: KU Leuven
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

Study for Promotion of Health in Recycling Lead (SPHERL) is a prospective 2-year follow-up study of lead workers with exposure levels varying between and within individuals. SPHERL addresses to what extent between-subject differences or within-subject changes in lead exposure may have a measurable impact on blood pressure, the cardiovascular system, renal function, the autonomic nervous system, peripheral nervous conduction velocity, and neurocognitive function.

At the beginning of December 2015, 70 participants were included in the study.

Description:

Background

• Whether low-level lead exposure impacts on blood pressure, regulation of the cardiovascular system, glomerular or tubular renal function, sympathetic nervous modulation, peripheral nervous conduction velocity, and neurocognitive function remains uncertain.

Study Population

• SPHERL will enroll 500 lead recycling workers with changing lead exposure, who will be examined at baseline (2014-2015) and followed up at annual intervals for 2 years (2016-2017).

Methods

• Volunteers eligible for the study are (i) new and existing hires without previous occupational lead exposure who will be performing tasks with or without occupational lead exposure and (ii) existing hires with occupational lead exposure who will be transitioning to job tasks without occupational lead exposure within the next 2 years.

• Blood lead concentration will be the main biomarker of exposure.

• The main outcome variables are (i) blood pressure measured conventionally and by ambulatory monitoring, and analyzed as continuous or categorical variable, both cross-sectionally and longitudinally; (ii) indexes of glomerular and tubular renal function, (iii) heart rate variability analyzed in the frequency domain as measure of autonomous sympathetic modulation, (iv) peripheral nerve conductivity, (v) neurocognitive performance, (vi) and quality of life [the EuroQOL five dimensions (EQ-5D) questionnaire].

Expected Outcomes

• Assuming a 4-fold or higher surge in the blood lead concentration, the study is powered to demonstrate over 2 years an acceleration in the age-related rise of systolic blood pressure by 1 to 4 mm Hg or an increase of the coefficient of multiple determination (R2) from 0.22 to 0.24 by adding the change in the blood lead concentration to models relating changes in blood pressure to three other covariables. The longitudinal design of our study complies with the temporality principle of the Bradford-Hill criteria for assessing possible causality between outcomes and exposure.

Recruitment information / eligibility

• Status: Active, not recruiting
• Enrollment: 270
• Est. completion date: December 31, 2024
• Est. primary completion date: July 1, 2024
• Accepts healthy volunteers: No
• Gender: All
• Age group: N/A and older

Eligibility

Inclusion Criteria:

• Women and men are eligible.

• New hires without previous occupational lead exposure who will be performing tasks with lead exposure or current employees without previous occupational lead exposure moving to tasks with exposure.

• Informed written consent.

Exclusion Criteria:

• Pregnancy.

• Any serious health condition.

Related Conditions & MeSH terms

• Occupational Exposure

Locations

Country	Name	City	State
Belgium	University of Leuven	Leuven

Sponsors (1)

Lead Sponsor	Collaborator
KU Leuven

Country where clinical trial is conducted

Belgium, 

References & Publications (1)

Hara A, Gu YM, Petit T, Liu YP, Jacobs L, Zhang ZY, Yang WY, Jin Y, Thijs L, Wei FF, Nawrot TS, Staessen JA. Study for Promotion of Health in Recycling Lead - Rationale and design. Blood Press. 2015 Jun;24(3):147-57. doi: 10.3109/08037051.2014.996409. Epu — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Annual change in systolic blood pressure as measured by 24-h ambulatory monitoring		Baseline, 1 year and 2 years
Secondary	Annual change in central hemodynamics	Annual changes in the central hemodynamics, including aortic blood pressure, the central systolic augmentation index, and aortic pulse wave velocity	Baseline, 1 year and 2 years
Secondary	Annual change in heart function	Annual changes in ECG-derived indexes	Baseline, 1 year and 2 years
Secondary	Annual change in renal function	Annual changes in glomerular and tubular renal function measured on a continuous scale and the incidence of renal dysfunction	Baseline, 1 year and 2 years
Secondary	Annual change in autonomic nervous function	Annual changes in alterations in the autonomic nervous cardiovascular modulation, as assessed by heart rate variability	Baseline, 1 year and 2 years
Secondary	Annual change in peripheral nervous conduction velocity	Annual changes in nerve conduction velocity	Baseline, 1 year and 2 years
Secondary	Annual change in neurocognitive performance	Annual changes in neurocognitive testing	Baseline, 1 year and 2 years
Secondary	Annual change in quality of life	Annual changes in self-assessed quality of life	Baseline, 1 year and 2 years