CRP levels are elevated in smokers but unrelated to the number of cigarettes and are decreased by long-term smoking cessation in male smokers.
BACKGROUND
It is not clear whether there is a dose-response relationship between the number of cigarettes smoked per day and CRP level and whether there is a relationship between the length of smoking cessation and CRP level.


METHODS
Geometric mean levels of CRP were compared in smoking status groups for 1926 men aged 40 to 69 years using analysis of covariance.


RESULTS
After adjusting for several confounding factors, geometric mean levels of CRP (mg/L) were significantly different among the three smoking status groups (0.41 in non-smokers, 0.57 in current smokers, 0.48 in past smokers, P < 0.05). A linear trend was not found in the relationship between CRP level and number of cigarettes smoked per day. The mean CRP level in the long cessation (> or =5 years) group was significantly lower than that in the short cessation (<5 years) group (0.45 vs. 0.58, P < 0.05) and similar to that in the non-smokers group (0.45 vs. 0.41, NS).


CONCLUSIONS
CRP levels in current smokers are elevated but unrelated to the number of cigarettes smoked per day. In past smokers, long-term smoking cessation may contribute to the reduction in risk of development of cardiovascular diseases through inflammatory mechanisms.
Ohsawa
Masaki
M
Department of Hygiene and Preventive Medicine, School of Medicine, Iwate Medical University, Morioka, Iwate 020-8505, Japan. masakio@iwate-med.ac.jp
Okayama
Akira
A
Nakamura
Motoyuki
M
Onoda
Toshiyuki
T
Kato
Karen
K
Itai
Kazuyoshi
K
Yoshida
Yuki
Y
Ogawa
Akira
A
Kawamura
Kazuko
K
Hiramori
Katsuhiko
K
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D002097:C-Reactive Protein / Q000378:metabolism*; D002318:Cardiovascular Diseases / Q000503:physiopathology / Q000517:prevention & control; D003430:Cross-Sectional Studies; D006801:Humans; D007564:Japan / Q000453:epidemiology; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012907:Smoking / Q000097:blood* / Q000453:epidemiology; D016540:Smoking Cessation; D013997:Time Factors
D002097:C-Reactive Protein