Environmental lead exposure is associated with visit-to-visit systolic blood pressure variability in the US adults

A review of the evidence to support interim reference level for dietary lead exposure in adults

FDA developed the interim reference level (IRL) for lead of 3 μg/day in children and 12.5 μg/day in women of childbearing age (WOCBA) to better protect the fetus from lead toxicity. These IRLs correspond to a blood lead level (BLL) of 0.5 μg/dL in both populations. The current investigation was performed to determine if the IRL for WOCBA should apply to the general population of adults. A literature review of epidemiological studies was conducted to determine whether a BLL of 0.5 μg/dL is associated with adverse effects in adults. Some studies reported adverse effects over a wide range of BLLs that included 0.5 μg/dL adding uncertainty to conclusions about effects at 0.5 μg/dL; however, no studies clearly identified this BLL as an adverse effect level. Results also showed that the previously developed PTTDI for adults of 75 μg/day lead may not be health protective, supporting use of a lower reference value for lead toxicity in this population group. Use of the 12.5 μg/day IRL as a benchmark for dietary lead intake is one way FDA will ensure that dietary lead intake in adults is reduced.

Low-level lead exposure and cardiovascular disease: the roles of telomere shortening and lipid disturbance

Lead exposure contributing to cardiovascular diseases is known and recognized widely. As the deleterious effects of low lead exposure attained increasing attention over the last decades, there have been numerous studies exploring the association of low levels of lead exposure and cardiovascular diseases. Moreover, it has been observed that lead exposure could cause telomere shortening and lipid disturbance, and that telomere shortening and lipid disturbance are closely related with cardiovascular diseases. Hence, telomere shortening and lipid disturbance might play an important role in the pathophysiological process of chronic low levels of lead exposure contributing to cardiovascular diseases. This review is intended to explore views of the rarely mentioned mechanism, telomere shortening and lipid disturbance, and the cardiovascular effects of low levels of lead exposure.

Association between blood lead level and blood pressure: An occupational population-based study in Jiangsu province, China

Studies about the association between lead exposure and the elevation of blood pressure and risk of hypertension are varied, while available data on blood lead levels (BLL) in workers with lead-exposure are scarce. This research aimed to evaluate associations between BLL and blood pressure in an occupational population-based study in Jiangsu province, China. We enrolled 21,688 workers in this study. Information on socioeconomic and occupational background was obtained with face-to-face interviews. BLL, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured, and hypertension status was confirmed. We found that workers in mini-factories had the highest average BLL (20.3 μg/dL; 95% CI, 19.0-21.6 μg/dL) for overall participants. The employees in private factories had higher BLL (9.6 μg/dL; 95% CI, 9.5-9.8 μg/dL). However, BLL was much lower (4.0 μg/dL; 95%CI, 3.7-4.2 μg/dL) in state-owned factories. Participants working in the electrical machinery and equipment manufacturing industry had higher BLL (9.1 μg/dL; 95% CI, 9.0-9.3μg/dL). Compared to those workers with ≤ 4.6 μg/dL BLL, workers with > 17.5 μg/dL BLL presented 1.34 mmHg and 0.70 mmHg average difference in SBP and DBP, respectively. The adjusted OR for hypertension was 1.11 (95%CI, 1.08-1.15) compared to the workers with > 17.5 μg/dL BLL and to those with ≤ 4.6 μg/dL BLL. In summary, we found that BLL was positively associated with SBP and DBP and with the morbidity of hypertension in occupational populations with a high concentration of lead exposure. It is important to formulate new standards of blood lead levels to screen for elevated lead exposure. In addition, a series of new systems of risk assessment should be established to further reduce and prevent lead exposure.

Obesity is associated with visit-to-visit systolic blood pressure variability in the US adults

BACKGROUND

Evidence has accumulated showing that blood pressure variability is associated with cardiovascular disease. A substantial increase in the prevalence of obesity has been documented globally. Our objective was to examine the relation of total and central obesity on visit-to-visit blood pressure variability.

METHODS

We used data collected from the cross-sectional Third National Health and Nutrition Examination Survey, to examine the association of visit-to-visit blood pressure variability with body mass index and waist circumference.

RESULTS

The analysis included 14,988 participants. The participants' mean age was 43.45 years. Visit-to-visit systolic blood pressure variability was associated with a body mass index ≥30 and a large waist circumference (beta coefficients were 0.25 and 0.31, respectively, P-values < 0.01). Neither the bivariate nor the multivariable analyses showed significant relationships between the obesity indicators and diastolic blood pressure variability.

CONCLUSIONS

Obesity is associated with visit-to-visit systolic blood pressure variability. Additional research is required to replicate the reported results in prospective studies and evaluate approaches to reduce blood pressure variability observed in clinical settings among obese persons to reduce its subsequent complications.