Division of Hematology, St. Luke's International Hospital, Japan.
Division of Gastroenterology, St. Luke's International Hospital, Japan; Center for Clinical Epidemiology, St. Luke's International University, Japan.
Prev Med Rep. 2016 Aug 9;4:417-22. doi: 10.1016/j.pmedr.2016.08.009. eCollection 2016 Dec.
While cigarette smoking is a well-recognized cause of elevated white blood cell (WBC) count, studies on longitudinal effect of smoking cessation on WBC count are limited. We attempted to determine causal relationships between smoking and elevated WBC count by retrospective cross-sectional study consisting of 37,972 healthy Japanese adults who had a health check-up between April 1, 2008 and March 31, 2009 and longitudinal study involving 1730 current smokers who had more than four consecutive annual health check-ups between April 1, 2007 and March 31, 2012. In the cross-sectional study, younger age, male gender, increased body mass index, no alcohol habit, current smoking, and elevated C-reactive protein level were associated with elevated WBC count. Among these factors, current smoking had the most significant association with elevated WBC count. In subgroup analyses by WBC differentials, smoking was significantly associated with elevated counts of neutrophils, lymphocytes, monocytes, eosinophils, and basophils. Ex-smoking was not associated with elevated WBC count. In the longitudinal study, both WBC and neutrophil counts decreased significantly in one year after smoking cessation and remained down-regulated for longer than next two years. There was no significant change in either WBC or neutrophil count in those who continued smoking. These findings clearly demonstrated that current smoking is strongly associated with elevated WBC count and smoking cessation leads to recovery of WBC count in one year, which is maintained for longer than subsequent two years. Thus, current smoking is a significant and reversible cause of elevated WBC count in healthy adults.
虽然吸烟是白细胞（WBC）计数升高的一个公认原因，但关于戒烟对 WBC 计数的纵向影响的研究有限。我们试图通过回顾性横断面研究和纵向研究来确定吸烟与白细胞计数升高之间的因果关系。横断面研究纳入了 37972 名 2008 年 4 月 1 日至 2009 年 3 月 31 日期间接受健康检查的日本健康成年人，该研究为回顾性横断面研究；纵向研究纳入了 1730 名连续 4 年以上（2007 年 4 月 1 日至 2012 年 3 月 31 日）接受年度健康检查且目前吸烟的人群。在横断面研究中，年龄较小、男性、体重指数增加、无饮酒习惯、当前吸烟和 C 反应蛋白水平升高与白细胞计数升高有关。在这些因素中，当前吸烟与白细胞计数升高的关联最显著。在白细胞分类计数的亚组分析中，吸烟与中性粒细胞、淋巴细胞、单核细胞、嗜酸性粒细胞和嗜碱性粒细胞计数升高显著相关。戒烟与白细胞计数升高无关。在纵向研究中，戒烟后一年白细胞和中性粒细胞计数显著下降，且在随后的两年中持续下调。继续吸烟的人群中，白细胞和中性粒细胞计数没有明显变化。这些发现清楚地表明，当前吸烟与白细胞计数升高密切相关，戒烟可在一年内恢复白细胞计数，且在随后的两年中持续恢复。因此，当前吸烟是健康成年人白细胞计数升高的一个重要且可逆转的原因。
