Blood eosinophil reference values and determinants in a representative adult population

Background

The use of blood eosinophil count (BEC) as a prognostic biomarker in the management of conditions such as asthma and chronic obstructive pulmonary disease (COPD) may be complicated by factors such as atopy, age, sex, smoking, and comorbidities.

Objective

We sought to produce reference values for BEC, considering age, asthma, COPD, and clinical allergy for the general adult population.

Methods

The West Sweden Asthma Study constitutes a population-representative clinical epidemiological cohort of randomly selected adults in Western Sweden. From this cohort, 1145 individuals took part in clinical examinations, including skin prick testing, specific IgE, and BEC.

Results

The upper limit (95th percentile) of BEC varied by age. It ranged from 400 to 500 cells/μL in the full sample and from 300 to 400 cells/μL in subjects without asthma, COPD, and clinical allergy (n = 710). Sex, smoking, atopy, clinical allergy, obesity, asthma, COPD, diabetes, and hypertension were statistically significantly associated with higher BEC levels. However, only asthma and clinical allergy in the full sample, and obesity and diabetes in those without asthma, COPD, or clinical allergy, remained statistically significant with higher BEC levels in multivariable regression analyses.

Conclusions

In a population-representative sample, the upper limit of BEC in healthy adults ranged between 300 and 400 cells/μL, varying by age. Age, smoking, obesity, asthma, COPD, and clinical allergy influence BEC levels and should be considered in clinical interpretation.

National Couples' Health and Time Study: Sample, Design, and Weighting

The National Couples' Health and Time Study (NCHAT) is the first fully powered, population-representative study of couples in America containing large samples of sexual, gender, and racial and ethnic diverse individuals. Drawn from the Gallup Panel and the Gallup Recontact Sample, when weighted, the data are population representative of individuals in the United States who (1) are married or cohabiting, (2) are between 20 and 60, (3) speak English or Spanish, and (4) have internet access. The data were collected between September 2020 and April 2021 in the midst of a global pandemic as well as racial and political upheaval. NCHAT includes surveys of 3,642 main respondents and 1,515 partners along with time diaries. We describe the sampling process, challenges weighting a diverse population-representative samples, and sociodemographic characteristics of the NCHAT study. These data will provide opportunities for new research on the health and well-being of American families.