Evaluation of the ambulatory arterial stiffness index in lead-exposed workers

Abstract

Objective:Lead exposure has been associated with various cardiovascular disorders. It may also cause increased inflammation and fibrosis in the arterial system resulting in an increase in arterial stiffness. In this study, the ambulatory arterial stiffness index (AASI), which is a technique that measures arterial stiffness, was evaluated in occupationally lead-exposed workers.Methods:In this cross-sectional study, 68 lead-exposed workers without known cardiovascular risk factors and 68 healthy subjects were evaluated according to the 24-hour ambulatory blood pressure monitorization (ABPM) profiles and blood and 24-hour urine lead levels. A regression slope of diastolic over systolic blood pressure (BP) was computed in each participant. AASI was defined as 1 minus the regression slope.Results:There were no significant differences in terms of baseline demographic, clinical, echocardiographic characteristics, and ABPM profiles between the groups. In lead-exposed workers, the mean age was 34.7±8.1 years, and the median blood and urine lead levels were 40.5 µg/dL and 34.9 µg/L, respectively. AASI was 0.42±0.10 in lead-exposed workers and 0.37±0.10 in control subjects (p=0.007). In correlation analysis, AASI was correlated with both blood (r=0.417, p<0.001) and urine lead (r=0.242, p=0.047) levels. In regression analysis, blood lead level was found to be associated with AASI (b=0.086, p<0.001).Conclusion:AASI, which is an indicator of arterial stiffness, was found to be higher in lead-exposed workers than in healthy individuals. Increased AASI may be considered an early sign of arterial involvement in case of lead exposure.

Central hemodynamics in relation to low-level environmental lead exposure

“…Few previous studies addressed the potential association of arterial stiffness with lead exposure [9][10][11][12][13][14][15][16][17][18][19]. Interpretation of these studies is difficult, because most focused on the occupational exposure to lead [15][16][17][18][19], applied a suboptimal method to assess central hemodynamics [15,16], had a small sample size [19], or case-control design [15,17,18]. Four studies, all in an occupational setting, focused on central hemodynamics [16][17][18][19].…”

“…In comparison with the literature on the possible association of arterial stiffness and exposure to lead [9][10][11][12][13][14][15][16][17][18][19], our current study moves the field forward; because it is population based, thereby excluding the healthy-worker effect [35]; because a large panel of central hemodynamic variables was assessed, including aPWV, the gold standard in measuring arterial stiffness [7], as well as the forward and backward pulse pressure waves; and because we evaluated coexposure to cadmium. Moreover, our study is representative for current day environmental exposure levels, which are substantially lower than in the cited worker studies [15][16][17][18][19]. Nevertheless, our current findings must also be interpreted within the context of their limitations.…”

“…Whereas there is an abundant, albeit contradictory, literature on the association of blood pressure with lead exposure, a PubMed search using as keywords "pulse pressure" OR "augmentation index" OR "pulse wave velocity" OR "arterial stiffness" combined with "exposure" or "lead exposure" revealed only ten articles of potential relevance to the research issue addressed in this article. These studies described the association of peripheral pulse pressure [9][10][11][12][13][14], the ambulatory arterial stiffness index [15], or central hemodynamic measurements [16][17][18][19] with the lead concentration in blood [9][10][11][12][13][14][15][16][17][18], urine [15], toenails [19], or bone [10,11,13]. Our objective was to address this knowledge gap.…”

Central hemodynamics in relation to blood lead in young men prior to chronic occupational exposure

“…The interpretation of the scant literature on the possible association of central hemodynamics with lead exposure is difficult [18][19][20][21]39], because most studies applied a suboptimal method to assess central hemodynamics [18,39], had a small sample size [21], or had a case-control design [18][19][20]. Among 420 men working as bus drivers in Bangkok [39], Thailand, age averaged 41.6 years and the blood lead concentration ranged from 2.5 to 16.2 lg/dL (mean, 6.3 lg/dL).…”

“…Advancing age and higher blood pressure are the main drivers of arterial stiffening and increased aortic pulse wave velocity [5,11]. Whereas there is an abundant, but contradictory, literature on the association of blood pressure with lead exposure, a PubMed search using as keywords "pulse wave velocity" OR "augmentation index" OR "arterial stiffness" OR "pulse pressure" combined with "exposure" or "lead exposure" revealed only ten articles of potential relevance, describing the association of peripheral pulse pressure [12][13][14][15][16][17], the ambulatory arterial stiffness index [18], or central hemodynamic measurements [19][20][21] with the lead concentration in blood [12][13][14][15][16][17][18][19][20], urine [18], toenails [21] or bone [13,14,16]. We therefore assessed the association of central hemodynamic measurements, including central blood pressure, systolic augmentation, aortic pulse wave velocity and pulse wave reflection, with blood lead, using the first in-study assessment (2015)(2016)(2017) collected in the ongoing Study for Promotion of Health in Recycling Lead (SPHERL; NCT02243904).…”