Red Blood Cell Distribution Width: A Novel Predictive Indicator for Cardiovascular and Cerebrovascular Diseases
Table 6
Studies exploring association between red blood cell distribution width (RDW) and primary hypertension.
First author, journal, year
Study design
Study population
Mean follow-up
Major outcomes
Major limitations
(i) Tanindi et al. [59]
(ii) Blood Pressure
(iii) 2012
Cross-sectional and observational study
128 patients with hypertension, 74 patients with prehypertension and 36 healthy controls, age >18 years
—
(i) Mean RDW values were 15.26 ± 0.82, 16.54 ± 0.91 and 13.87 ± 0.94 in prehypertensive, hypertensive and control groups, respectively ().
(ii) Systolic and diastolic blood pressures were strongly correlated with RDW ( and , resp., )
(i) The sample size was relatively small
(ii) Control group included the patients who are not completely normal
(iii) Not rule out the possibility of residual confounding
(iv) It does not explain the exact mechanism
(i) Sen-Yu et al. [134]
(ii) Journal of Obstetrics and Gynaecology Research
(iii) 2016
Retrospective study
149 pregnancies with pregnancy hypertension disease and 70 health pregnant women as controls, age>18 years
10 months
RDW in different gestational time (20th week, 24th week, 28th week) of different pregnant women groups had differences (), but pregnant women in the same group had no difference from 20th week to 28th week ()
(i) The sample size was relatively small
(ii) Not rule out the possibility of residual confounding
(i) Reddy et al. [135]
(ii) International Journal of Advances in Medicine
(iii) 2016
Cross-sectional and observational study
200 patients and 100 controls, age >50 years
—
Hs-CRP levels and RDW levels are both equally effective as a predictive marker for hypertension
(i) No further statistical analysis
(ii) The sample size was relatively small
(iii) RDW value was measured only once
708 patients with essential hypertension, age 18–90 years
—
There was significantly increased RDW in reverse dippers (13.52 ± 1.05) than dippers (13.25 ± 0.85) of hypertension ()
(i) There was no a longer period of prospective observation providing more prognostic information
(ii) The participants in our study are exclusively limited to northern Chinese patients from a single center
(iii) They excluded 10 extreme dippers from the analysis in this study for their small sample size
(i) Özcan et al. [137]
(ii) Blood Pressure
(iii) 2013
Cross-sectional study
(i) 127 dipper patients, mean age, 52 ± 12 years
(ii) 120 non-dipper patients, mean age, 54 ± 13 years
—
Nondippers had significantly higher RDW levels than dippers (14.6 versus 13.0, , resp.)
(i) It just represented a single-center experience
(ii) Nondipper hypertensive patients were not followed-up in terms of future adverse cardiovascular events
(iii) It does not explain the exact mechanism