UCLA

Importance

Elevated blood lead levels in children are associated with neurologic effects such as behavioral and learning problems, lower IQ, hyperactivity, hearing problems, and impaired growth. In pregnant women, lead exposure can impair organ systems such as the hematopoietic, hepatic, renal, and nervous systems, and increase the risk of preeclampsia and adverse perinatal outcomes. Many of the adverse health effects of lead exposure are irreversible.

Objective

To update the 2006 US Preventive Services Task Force (USPSTF) recommendation on screening for elevated blood lead levels in children and pregnant women.

Evidence review

The USPSTF reviewed the evidence on the benefits and harms of screening for and treatment of elevated blood lead levels. In this update, an elevated blood lead level was defined according to the Centers for Disease Control and Prevention reference level of 5 μg/dL.

Findings

The USPSTF found adequate evidence that questionnaires and other clinical prediction tools to identify asymptomatic children with elevated blood lead levels are inaccurate. The USPSTF found adequate evidence that capillary blood testing accurately identifies children with elevated blood lead levels. The USPSTF found inadequate evidence on the effectiveness of treatment of elevated blood lead levels in asymptomatic children 5 years and younger and in pregnant women. The USPSTF found inadequate evidence regarding the accuracy of questionnaires and other clinical prediction tools to identify asymptomatic pregnant women with elevated blood lead levels. The USPSTF found inadequate evidence on the harms of screening for or treatment of elevated blood lead levels in asymptomatic children and pregnant women. The USPSTF concluded that the current evidence is insufficient, and that the balance of benefits and harms of screening for elevated blood lead levels in asymptomatic children 5 years and younger and in pregnant women cannot be determined.

Conclusions and recommendation

The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for elevated blood lead levels in asymptomatic children. (I statement) The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for elevated blood lead levels in asymptomatic pregnant persons. (I statement).