Higher Mean Corpuscular Volume Levels Research Articles

The cross-sectional association between mean corpuscular volume level and cognitive function in Chinese over 45 years old: Evidence from the China Health and Retirement Longitudinal Study

Fewer studies have focused on the independent association between mean corpuscular volume (MCV) and cognitive performance. This study was designed to characterize the cross-sectional association between MCV and cognitive performance in a large sample of Chinese residents (age≥45 years) from the China Health and Retirement Longitudinal Study (CHARLS). A total of 4023 male and 4173 female adults with MCV ≥ 80 fl were included for analysis. By multivariable linear regression analysis, for the total subjects, MCV level was significantly negatively associated with global cognitive function and episodic memory. When adjusted by sex, only in male subjects, higher MCV level was associated with reduced scores for global cognitive function, episodic memory and mental status. Via binary logistic regression analysis, the higher MCV level (MCV>100 fl) was associated with poor global cognitive function (OR = 1.601; 95% CI = 1.198-2.139; p = 0.001), episodic memory (OR = 1.679; 95% CI = 1.281-2.201; p<0.001), and mental status (OR = 1.422; 95% CI = 1.032-1.959; p = 0.031) for the whole participants. When testing this association by sex, the significant relationship between higher MCV level with worse episodic memory was observed both in male (OR = 1.690; 95% CI = 1.211-2.358; p = 0.002) and female (OR = 1.729; 95% CI = 1.079-2.770; p = 0.023) subjects; while the association between higher MCV level and poor global cognitive function (OR = 1.885; 95% CI = 1.329, 2.675; p<0.001) and mental status (OR = 1.544; 95% CI = 1.034, 2.306; p = 0.034) only existed in male subjects. Further studies are warranted to clarify the association between MCV level and cognitive performance by considering sex into consideration both cross-sectionally and longitudinally.

Mean Corpuscular Volume and Mortality in Incident Hemodialysis Patients

Background/Aims: Anemia is common in patients with advanced chronic kidney disease (CKD). A proportion of patients present with macrocytic anemia, manifested by elevated mean corpuscular volume (MCV), which has been associated with worse outcomes in CKD patients. However, it is unknown whether elevated MCV is associated with higher mortality risk in incident hemodialysis (HD) patients. Methods: This retrospective observational cohort study examined all-cause, cardiovascular, and infectious mortality associations with both baseline and time-varying MCV in 109,501 incident HD patients using Cox proportional hazards models with 3 levels of hierarchical multivariable adjustment. Odds ratios of high versus low baseline MCV were evaluated using logistic regression. Results: The mean age of patients was 65 ± 15 (standard deviation) years and the cohort was 44% female, 58% diabetic, and 31% African American. Higher MCV was associated with older age, female sex, non-Hispanic White race-ethnicity, alcohol consumption, and having a decreased albumin or protein intake. Patients with higher MCV levels (> 98 fL) had a higher all-cause, cardiovascular, and infectious mortality risk in both baseline and time varying models, and across all levels of adjustment. In the fully adjusted models, compared to a reference of MCV 92–< 94 fL, patients with a baseline MCV > 100+ fL had a 28% higher risk of all-cause mortality (hazard ratio [HR] 1.28, 95% CI 1.22–1.34), 27% higher risk of cardiovascular mortality (HR 1.27, 95% CI 1.18–1.36), and 18% higher risk of infectious mortality (HR 1.18, 95% CI 1.02–1.38). Associations of higher MCV with these adverse outcomes persisted across all examined subgroups of clinical characteristics. Conclusions: Higher MCV was associated with higher all-cause, cardiovascular, and infectious mortality in HD patients. Further investigation is necessary to understand the underlying nature of the observed association.

Mean Corpuscular Volume (MCV) Values Reflect Therapeutic Effectiveness in Zidovudine‐Receiving HIV Patients

An increase of the mean corpuscular volume (MCV) of erythrocytes and alterations in the lipid profiles have been described in HIV-infected patients under combination of anti-retroviral treatment (cART), particularly zidovudine (AZT). In 687 sera from 179 HIV-positive patients, MCV levels were correlated with the clinical outcome or therapeutic effectiveness. The sera were classified into three groups according to AZT treatment; cART with AZT (n = 317), cART without AZT (n = 262), and no anti-retroviral therapy (n = 108). The MCV and lipid profile values were increased after cART. The AZT-based cART group had higher MCV levels (111.6 ± 7.0 vs. 97.8 ± 7.0 fl, P < 0.001) and a higher incidence of macrocytosis (>99 fl; 95.3% vs. 38.2%, P < 0.001) than the non-AZT-based cART group. The receiver operating characteristic curve analysis showed that the area under the curve was 0.835 and the cut-off of MCV (>102 fl) had a sensitivity of 96.1% and specificity of 66.7% for detecting HIV-RNA (-) sera in AZT-based cART group. In the multivariate regression analysis, HIV-viral load and HDL-cholesterol were the only significant correlates to the MCV values in the AZT-base cART group (P < 0.05). The MCV values could be used as a surrogate marker to monitor the clinical outcome of HIV-infected patients receiving AZT-based cART.

Association between erythrocyte mean corpuscular volume and peripheral arterial disease in male subjects: a case control study.

Elevated serum total homocysteine, an established risk factor for peripheral arterial disease, is influenced by the vitamin B12 and folate status. Since these vitamins are inversely correlated with erythrocyte mean corpuscular volume, an investigation of whether mean corpuscular volume is higher in patients with symptomatic peripheral arterial disease than in healthy subjects was performed. Furthermore, a determination of predictors of increased mean corpuscular volume levels in this population free of symptomatic coronary artery disease, cerebrovascular disease, and diabetes mellitus was carried out. From 469 consecutive patients with symptomatic peripheral arterial disease, 100 fulfilled study inclusion criteria. Peripheral arterial disease was confirmed by angiography. One hundred age-matched subjects without peripheral arterial disease as verified by ankle-brachial index measurements >0.9 served as control subjects. Patients with PAD displayed a significantly higher mean corpuscular volume level (94.5 fl) than control subjects (90.9 fl, p<0.001). Logistic regression analysis showed that current smoking status (p<0.001) and mean corpuscular volume (p=0.009), but not total homocysteine or lipid parameters discriminated case control status. In addition, logistic regression analysis revealed a relationship of mean corpuscular volume with smoking (p=0.001), gamma-glutamyltransferase (p<0.001), and total homocysteine (p=0.012). This model predicted mean corpuscular volume values with an accuracy of 83%. Elevated mean corpuscular volume is a predictor of symptomatic peripheral arterial disease in the sample studied. A deficiency of folate and/or vitamin B12 may be responsible for this observation, as indicated by the correlation of mean corpuscular volume with total homocysteine. Due to the additional association of mean corpuscular volume with smoking and gamma-glutamyltransferase, an unhealthy lifestyle with low vitamin intake may cause elevated mean corpuscular volume values in patients with PAD.

Relation of serum ascorbic acid to serum vitamin B12, serum ferritin, and kidney stones in US adults.

Concern has been raised that high levels of ascorbic acid consumption may lead to potential adverse effects, such as vitamin B12 deficiency, iron overload, and kidney stones. To examine the relation of serum ascorbic acid level, which reflects intake, to serum vitamin B12 level, serum ferritin level, and kidney stones. We analyzed data collected on a random sample of the US population enrolled in the Second National Health and Nutrition Examination Survey, 1976-1980. We analyzed data using linear and logistic regression models. Serum ascorbic acid, serum vitamin B12, hemoglobin, red blood cell mean corpuscular volume (MCV), and serum ferritin levels were measured using standardized protocols. History of kidney stones was determined by self-report. After multivariate adjustment, serum ascorbic acid level was associated with higher serum vitamin B12 levels among women in regression models that assumed a linear relationship; each 57-pmol/L (1.0-mg/dL) increase in serum ascorbic acid level (range, 6-153 micromol/L [0.1 to 2.7 mg/dL]) was independently associated with a serum vitamin B12 level increase of 60 pmol/L (81 pg/ mL) (P<.001). Among men, serum ascorbic acid level was marginally associated with higher serum vitamin B12 levels: each 57-micromol/L (1.0-mg/dL) increase in serum ascorbic acid level was associated with a serum vitamin B12 level increase of 27 pmol/L (36 pg/mL) (P = .10). In addition, serum ascorbic acid level was not associated with correlates of vitamin B12 deficiency, such as higher MCV levels, macrocytosis (MCV >100), or lower hemoglobin concentrations. Serum ascorbic acid level was not independently associated with serum ferritin levels. However, among women only, serum ascorbic acid levels were associated in a nonlinear fashion with prevalence of elevated serum ferritin levels (P = .02). We found no association between serum ascorbic acid level and prevalence of kidney stones in women or men (both P>.05). Serum ascorbic acid levels were not associated with decreased serum vitamin B12 levels (or indicators of vitamin B12 deficiency), prevalence of kidney stones, serum ferritin levels, or-among men-prevalence of elevated serum ferritin levels. Serum ascorbic acid levels were associated with prevalence of elevated serum ferritin levels among women. Although the clinical relevance of these findings is uncertain, it seems prudent to suggest that women with a genetic susceptibility to iron overload should consider moderating their intake of ascorbic acid.