Inverted U-shaped curve relationship between red blood cell distribution width and hypertension in a large health checkup population in China

Association between red cell distribution width and hypertension: Results from NHANES 1999-2018

The relationship between red cell distribution width (RDW) and hypertension remains a contentious topic, with a lack of large-scale studies focusing on the adults in the United States. This study aimed to investigate the association between RDW and hypertension among US adults from 1999 to 2018.

METHODS

Data were derived from the National Health and Nutrition Examination Survey (NHANES) 1999-2018. RDW values were obtained from the Laboratory Data's Complete Blood Count with 5-part Differential-Whole Blood module. Hypertension data were obtained through hypertension questionnaires and blood pressure measurements. Multivariable weighted logistic regression analyses were conducted to assess the association between RDW and hypertension, followed by subgroup and smooth curve analyses.

RESULTS

Compared to the non-hypertensive group, the hypertensive group exhibited higher RDW values (13.33±1.38 vs. 12.95±1.27, P <0.001). After adjusting for covariates, weighted multivariable logistic regression analysis revealed a positive correlation between RDW and hypertension prevalence (OR: 1.17, 95% CI 1.13, 1.21, P <0.001). When RDW was included as a categorical variable, participants in the fourth quartile had the highest risk of hypertension (OR: 1.86, 95% CI 1.70, 2.03, P <0.001). Subgroup analysis showed that, except for age, BMI and weak/failing kidneys, gender, race, education level, smoking, alcohol use, congestive heart failure, and stroke did not significantly influence this correlation (all P-values for interaction >0.05).Smooth curve fitting analysis revealed a reverse J-shaped relationship between RDW and hypertension prevalence, with an inflection point at 12.93%.

CONCLUSION

We first explored the relationship between RDW and hypertension among US adults and discovered a reverse J-shaped association, providing further insights into the relationship between blood cell counts and hypertension and offering a new foundation for hypertension prevention and control.

The V-shaped curve relationship between fasting plasma glucose and human serum albumin in a large health checkup population in China

BACKGROUND

This study aimed to investigate the relationship between fasting plasma glucose (FPG) and human serum albumin (HSA) in a large health checkup population in China.

METHODS

In this cross-sectional health checkup study, we enrolled a population of 284,635 subjects from Wuhu between 2011 and 2016. All participants completed the physical examination, blood biochemical examination, and blood routine examination.

RESULTS

The prevalence of diabetes in men and women was 6.11% and 2.98%, respectively. The average level of HSA and FPG was significantly higher in men than in women (48.44 ± 3.25 vs. 47.14 ± 3.22, P < 0.0001; 5.50 ± 1.26 vs. 5.26 ± 0.94, P < 0.0001). There were significant differences in blood biochemistry and blood routine values by gender. After adjusting for confounding factors, the results showed that FPG and HSA were a V-shaped curve, and the threshold value of HSA was 40.7 mmol/L. FPG and HSA still showed a V-shaped curve after stratification by gender and age. In the male group, FPG decreased with HSA when HSA<42.3 mmol/L, and increased when HSA ≥ 42.3 mmol/L. In the female group, FPG decreased with HSA when HSA<35.7 mmol/L, and increased when HSA ≥ 35.7 mmol/L. In the age<65 group, FPG decreased with HSA when HSA<37.5 mmol/L, and increased when HSA ≥ 37.5 mmol/L. In the age ≥ 65 group, FPG decreased with HSA when HSA<43.2 mmol/L, and increased when HSA ≥ 43.2 mmol/L.

CONCLUSIONS

A V-shape relationship exists between fasting plasma glucose and human serum albumin among the Chinese health checkup population studied.

Implications of gender-based variabilities in bone mineral density and hemoglobin levels

BACKGROUND

Studies reported that there is a relationship between volumetric bone mineral density (vBMD) and hemoglobin (HGB) in sickle cell anemia, chronic obstructive pulmonary disease, inflammatory bowel disease, and chronic kidney disease, it is not clear whether this association exists in normal populations or different genders. In order to further clarify the relationship between vBMD and HGB, and provide the basis for the diagnosis of related diseases, this study was conducted in the physical examination population.

METHODS

A cross-sectional study was conducted on a health check-up population from Wannan area of China from January to December 2018. The study involved 1238 individuals aged 23 to 85 years. Linear regression analysis and smooth curve were applied to determine the relationship of HGB and vBMD.

RESULTS

The average level of vBMD in the population was 130.11 ± 79.51 mg/cm³, after adjusting for age, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol (TC), triglycerides (TG), glucose (GLU), high-density lipoprotein (HDL) and low-density lipoprotein (LDL). A U-shape relationship was established between vBMD and HGB, the cut off value of HGB was 130 g/L. After gender stratification, the results showed a U-shaped curve relationship between vBMD and HGB in male group, and a linear relationship between vBMD and HGB in female group. The vBMD decreased with HGB when HGB < 120 g/L, and increased when HGB ≥ 120 g/L in male group.

CONCLUSION

The relationship between vBMD and HGB in the male physical examination population presents a U-shaped curve.

Metabolic syndrome in systemic lupus erythematosus was closely related to body mass index, blood pressure, blood sugar, blood lipids, and arthritis

Background and Objective:

Prevention and control of metabolic syndrome is the key to improving the development of systemic lupus erythematosus. The aim of this study was to analyze the relevant factors regarding metabolic syndrome (MS) in systemic lupus erythematosus (SLE).

Methods:

A total number of 1238 SLE patients in Yijishan Hospital of Wannan Medical College, Anhui province, from February 2012 to July 2017, were analyzed retrospectively. SLE patients with MS were grouped to group SLE-MS, the others without MS was grouped to group SLE-nMS. The two groups were compared with respect to general characteristics, clinical signs, and laboratory parameters. Random forest approach and multivariate logistic regression were conducted to analyze the related factors regarding MS in SLE.

Results:

The constituent ratio of metabolic syndrome was 27.14% (336/1238). More SLE patients with MS presented with more farmers, more married people, lower education level, and more lupus nephritis, proteinuria, oral ulcers, tubular urine, hematuria than SLE patients without MS (P<0.05). Moreover, eighteen important variables, whose average importance scores were highest and whose error rates were lowest, were selected by random forest method. Data from multivariate logistic regression showed that MS in SLE was related with BMI, diastolic blood pressure, systolic blood pressure, fasting blood glucose, arthritis, urea, triglycerides, high-density lipoprotein, and white blood cells.

Conclusion:

MS in SLE was closely related to BMI, blood pressure, blood sugar, blood lipids, arthritis, white blood cells, and urea. Targeted prevention and conclusion measures for the risk factors should be taken as early as possible.

The role of red blood cell distribution width (RDW) in cardiovascular risk assessment: useful or hype?

Red blood cell distribution width (RDW) reflects erythrocyte size distribution, thus representing a reliable index of anisocytosis, widely used for the differential diagnosis of micro- and normocytic anaemias. Along with the large use in diagnostic hematology, RDW has been associated with presence and complications of a vast array of human pathologies during the last decades, including cardiovascular (CV) diseases. This article is hence aimed to provide an overview of important studies and systematic reviews with meta-analysis, in which RDW has been associated with CV events and mortality, in the attempt of establishing whether enough evidence exists for supporting its routine use in clinical practice. According to available data it seems reasonable to conclude that although the diagnostic specificity is low, and this measure is still plagued by important lack of standardization, RDW can be regarded as an index of enhanced patient fragility and higher vulnerability to adverse outcomes. Abnormal RDW values shall hence persuade physicians to broaden the diagnostic reasoning over anaemias, especially those due to malnutrition or malabsorption, encompassing a comprehensive assessment of traditional and non-traditional CV risk factors.

The association between red cell distribution width and incident hypertension in Korean adults

Red cell distribution width (RDW), a measure of variation in red blood cell size, is routinely reported in the results of a complete blood count. Recent studies have found that RDW is a predictor of high cardiovascular morbidity and mortality. Furthermore, previous cross-sectional studies have shown a possible association between high RDW and hypertension. However, the longitudinal relationship between high RDW and incident hypertension is uncertain. The aim of this study was to investigate the association between RDW and the development of hypertension. In this retrospective cohort study, we analyzed 124,261 participants without hypertension at baseline who underwent two health checkups at 4-year intervals from 2005 to 2016. The subjects were divided into quartiles (Q1-Q4) according to their baseline RDW levels. Multivariate logistic regression was used to estimate the OR and 95% CI for the development of hypertension after 4 years. After 4 years, 6827 cases (5.5%) of incident hypertension were observed. The incidence rates of hypertension were 4.66%, 5.66%, 5.99%, and 5.46% for Q1, Q2, Q3 and Q4 of RDW, respectively. The ORs (95% CIs) for incident hypertension compared with Q1 were 1.19 (1.10-1.29), 1.28 (1.18-1.39), and 1.32 (1.22-1.44) for Q2, Q3, and Q4 of RDW, respectively. High RDW was significantly and independently associated with the development of hypertension in Korean adults. Further research is warranted to verify the mechanism underlying this relationship.