[Red blood cell deformability in relation to gender, age, blood pressure, obesity, serum lipids, alcohol consumption and smoking].
OBJECTIVE
To determine the effects of environmental factors on abnormalities in red blood cell deformability (RBCD), which may play an important role in the development of cardiovascular diseases, a cross-sectional epidemiological study was conducted in healthy subjects.


METHODS
The subjects were 350 males (mean age 52.7 +/- 10.3 SD) and 364 females (52.6 +/- 10.4) who participated in a health check program in the town of Akabane, Japan, in 1995-1998. Blood and serum were obtained to determine the values of RBCD and TP, TG, TCHOL, and HDLC. The inverse of RBCD (RBCDI, ms-1) was used as an indicator of RBCD. The subjects were also investigated for drinking and smoking habits, BMI, and SBP. Males and females were stratified into tertiles for each variable except drinking and smoking. For those exceptions, male subjects were stratified into three groups according to alcohol consumption (non-drinkers, moderate drinkers (up to 27 ml pure ethanol per day), and habitual drinkers (28 ml or more per day)) and according to tobacco use (non-smokers, mild smokers (equal or fewer than 20 cigarettes per day), and heavy smokers, (more than 20)). Each stratum was further divided into two groups according to age (younger, < 50 years; older, > or = 50 years).


RESULTS
The mean value of RBCDI was significantly higher in males (1.041 +/- 0.135 SD) than in females (1.013 +/- 0.113). RBCDI declined with age in both genders. In analyses of variance, the averages of RBCDI decreased as TP increased in all ages and in both genders and as TCHOL increased in older males. With regard to alcohol consumption, the averages of RBCDI were the highest in moderate drinkers in younger males. Multiple linear regression analyses showed negative correlations between RBCDI values and age, TP or TCHOL values, and showed positive correlations between RBCDI values and BMI in males as well as negative correlations between RBCDI values and age and TP in females. When alcohol drinking was entered into the model, the statistical significance between TCHOL and RBCDI disappeared in males. No apparent relations between smoking habit and levels of SBP and TG to RBCDI were found.


CONCLUSIONS
RBCDI was higher in males than in females and higher in the younger group than in the older group. This study suggested that TCHOL may lower RBCDI and moderate drinking may improve it. Further epidemiological study is required to clarify these relationships.
Nasu
Keiko
K
Department of Nutrition, Shizuoka College, University of Shizuoka, Shizuoka Kenritsu Daigaku Tanki Daigakubu, 2-2-1 Osika, Shizuoka City, Shizuoka 422-8021, Japan.
Nakamura
Mieko
M
Aoki
Nobuo
N
Iitoi
Yoji
Y
Kondo
Imako
I
Kikuchi
Yuji
Y
D000328:Adult; D000367:Age Factors; D000368:Aged; D000428:Alcohol Drinking / Q000097:blood*; D001794:Blood Pressure / Q000502:physiology*; D004907:Erythrocyte Deformability / Q000502:physiology*; D005260:Female; D006801:Humans; D008055:Lipids / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood*; D012737:Sex Factors; D012907:Smoking / Q000097:blood*
D008055:Lipids