Jung W, Irwin M
Department of Psychiatry, University of California, San Diego VA Medical Center, 92161, USA.
Psychosom Med. 1999 May-Jun;61(3):263-70. doi: 10.1097/00006842-199905000-00002.
Epidemiological data suggest that the presence of a depressed mood combined with cigarette smoking increases the risk of cancer at sites associated with smoking and at sites not associated with smoking. This study tested the hypothesis that major depression and smoking together contribute to a decline of natural killer cell (NK) activity, an immune parameter thought to be important in immune surveillance.
A sample of 245 men were stratified into four groups: control subjects who were not smokers, control subjects who were smokers, subjects with major depression who were not smokers, and subjects with major depression who were smokers. Blood samples were obtained for measurement of total white blood cell (WBC) counts, differential cell counts, and assay of NK activity.
Major depression and cigarette smoking interact and were together associated with changes in WBC counts and NK activity. Depressed subjects who were smokers had higher WBC counts (p < .001) and lower NK activity (p < .01) than depressed nonsmoking subjects. However, WBC counts and NK activity were similar in control smokers and nonsmokers. Backward elimination regression analyses showed that the interaction of depression and smoking significantly (p < .001) predicted WBC counts and NK activity.
This study extends previous findings of immune alterations in patients with major depression. Major depression and smoking interact and together contribute to an elevation of total WBC count and a decline of NK activity.
流行病学数据表明，情绪低落与吸烟同时存在会增加与吸烟相关部位以及与吸烟无关部位患癌的风险。本研究检验了以下假设：重度抑郁症与吸烟共同导致自然杀伤细胞（NK）活性下降，NK活性是一种在免疫监视中被认为很重要的免疫参数。
将245名男性样本分为四组：不吸烟的对照组、吸烟的对照组、不吸烟的重度抑郁症患者组以及吸烟的重度抑郁症患者组。采集血样以测量白细胞（WBC）总数、细胞分类计数以及检测NK活性。
重度抑郁症与吸烟相互作用，共同与白细胞计数和NK活性的变化相关。吸烟的抑郁症患者比不吸烟的抑郁症患者白细胞计数更高（p <.001），NK活性更低（p <.01）。然而，吸烟对照组和不吸烟对照组的白细胞计数和NK活性相似。向后逐步回归分析表明，抑郁症与吸烟的相互作用显著（p <.001）预测了白细胞计数和NK活性。
本研究扩展了先前关于重度抑郁症患者免疫改变的研究结果。重度抑郁症与吸烟相互作用，共同导致白细胞总数升高和NK活性下降。
