Association Between Peripheral Blood Cell Count Abnormalities and Health-Related Quality of Life in the General Population

Abstract

Complete blood cell counts, including differentials, are widely available and change on aging. Peripheral blood cell counts outside the normal range have previously been associated with increased mortality rates and a number of comorbid conditions. However, data about the association between blood cell count abnormalities, other than anemia, and health-related quality of life (HRQoL) are scarce. We investigated the association between abnormalities in (differential) blood cell counts and HRQoL in 143 191 community-dwelling individuals from the prospective population-based Lifelines cohort. HRQoL was measured using the RAND 36-Item Health Survey. Logistic regression analyses were used to determine the effect of blood cell count abnormalities on the odds of having a lower score than an age- and sex-specific reference value for each domain. Leukocytosis, neutrophilia, and a high neutrophil to lymphocyte ratio were associated with impaired HRQoL across multiple domains, both for younger and older (≥60 years) individuals. Using multivariable models, we confirmed that these associations were independent of the potential confounding factors obesity, smoking, alcohol use, number of medications (as a measure of comorbidity), anemia, and mean corpuscular volume. The impact on HRQoL was most pronounced for high neutrophil levels. Further, high white blood cell counts proved to be a better marker for inferior HRQoL as compared to elevated high-sensitivity C-reactive protein levels. Decreased HRQoL in several domains was also observed for individuals with monocytosis, lymphocytosis, and thrombocytosis. Taken together, the present study demonstrates an association between inflammatory and myeloid-skewed blood cell counts and inferior HRQoL in community-dwelling individuals.

Figure 1.

Prevalence of blood cell count abnormalities among evaluable individuals. The definitions of blood cell count abnormalities were based on local laboratory reference intervals, as indicated in the methods section.

Figure 2.

Percentage of individuals, stratified according to age group and blood cell count abnormality, with a score below the age- and sex-specific cut-off values for the different domains of the RAND-36 health survey. ^A significant difference in the proportion having a score below the age- and sex-specific cut-off value in individuals with leukopenia or thrombocytopenia as compared to individuals with a normal blood cell count. *A significant difference in the proportion having a score below the age- and sex-specific cut-off value in individuals with leukocytosis or thrombocytosis as compared to individuals with a normal blood cell count. WBC = white blood cell.

Figure 3.

Forest plots demonstrating the odds ratios for having a lower score than the (age- and sex-specific) 25th percentile cut-off per HRQoL subscale, according to blood cell count abnormality. Logistic regression analyses included body mass index, smoking status, alcohol use, number of medications, presence of anemia and mean corpuscular volume as covariates. A blood cell count in the normal range was used as the reference group. For the NLR, the 2nd to 4th quintile was used as a reference. Circles indicate odds ratios for each cohort, with horizontal lines corresponding to 95% CI. CI = confidence interval; HRQoL = health-related quality of life; NLR = neutrophil to lymphocyte ratio.

Figure 4.

Percentage of individuals with a score below the age- and sex-specific cut-off value for the different domains of the RAND-36 health survey, according to differential blood cell count abnormality. ^A significant difference in the proportion having a score below the age- and sex-specific cut-off value in individuals with neutropenia, lymphopenia, monocytopenia, or lowest NLR quintile, as compared to individuals with a normal blood cell count. *A significant difference in the proportion having a score below the age- and sex-specific cut-off value in individuals with neutrophilia, lymphocytosis, monocytosis, basophilia, eosinophilia, or highest NLR quintile, as compared to individuals with a normal blood cell count. BP = bodily pain; GH = general health; MH = mental health; NLR = neutrophil to lymphocyte ratio; PF = physical functioning; RE = emotional role functioning; RF = physical role functioning; SF = social functioning; VT = vitality.