Blood lead levels in the United States “Oldest-Old” population

Abstract

Context. Previous studies have suggested significant endogenous lead release from bony stores in the elderly raising the concern for elevated blood lead levels in that population. Objective. We undertook to determine the range of blood lead levels in the “oldest-old” population, a demographic category that includes persons aged 80 years and older. Materials and methods. We analyzed blood lead level data from the National Health and Nutrition Examination Survey (NHANES) for the years 1999–2010 for persons aged 80 years and older. We also screened an inner-city population of patients aged 80 years of age and older presenting to an emergency department. Results. Among persons aged 80 years and older sampled in the NHANES surveys, the geometric mean blood lead level each year varied from 1.98 to 2.66 mcg/dL. Of the 2,168 measured blood lead levels, only 15 samples (0.69%) exceeded our a priori definition of an elevated blood lead level (greater than 10 mcg/dL). Of those 15 samples, the highest blood lead level was 15.3 mcg/dL. For our screening of an inner-city oldest-old population, we enrolled 76 subjects and found a geometric mean blood lead level of 1.72 mcg/dL. Discussion. Several considerations place elderly persons at a theoretically increased risk of elevated blood lead level, including previously documented birth cohort effect for blood lead levels with older cohorts having higher mean blood lead levels and concern for endogenous lead exposure due to release of lead from bony stores. However, our statistical analysis of NHANES data and screening of an inner-city oldest-old population suggests that elevated blood lead levels in this population are rare. Conclusion. Routine blood lead level screening in the elderly is not indicated.

Keywords:

• Lead poisoning
• Epidemiology
• Nutrition surveys
• Aged
• Urban health