Natural Killer Activity and Its Changes among Participants in a Smoking Cessation Intervention Program. A Prospective Pilot Study of 6 Months' Duration.

Abstract

We examined the effect of smoking cessation on natural killer (NK) activity of peripheral blood lymphocytes in terms of a prospective study of 27 Japanese subjects who participated in a smoking cessation intervention program. This program was delivered by means of group-counseling offering 7 sessions of about 2 hours over 6 months to help smokers to discontinue the habit. Thirteen subjects ceased smoking (quitters), while 14 continued to smoke (cigarette smokers). NK activity before the intervention was correlated positively with age (correlation coefficient=0.46, P<0.05). NK activity remained almost constant among quitters, comparing the activity before and after the intervention, while it decreased among cigarette smokers although it was not statistically significant. In the subgroup analysis, NK activity increased among those aged less than 65 years, or urine cotinine levels over 800 ng/ml before the intervention, especially among quitters, but there were no statistical significances. Multiple regression analysis showed changes in NK activity were correlated significantly only with age (standard regression coefficient=-0.44, P<0.05). These findings suggest that smoking cessation intervention programs might have been more effective for younger than elder subjects in consideration of NK activity.

Nasal lavage natural killer cell function is suppressed in smokers after live attenuated influenza virus

“…Because NK cells can control and regulate viral infections via killing of infected respiratory epithelial cells, altered NK cell functions in smokers could contribute to enhanced influenza infections. Although smoking has been shown to suppress peripheral NK cell activity ex vivo [22-26], the effects of smoking on respiratory NK cell functions are unknown [24]. …”

Changes in peripheral blood lymphocyte phenotypes distribution in patients with oral cancer/oral leukoplakia in Taiwan

“…This is because chemical carcinogens in the BQ, tobacco and alcohol may attack the protein, lipid and DNA of mucosal cells, leading to gene mutation, chromosomal aberrations and clinical oral cancer 30,34 . Most damaged DNA can be repaired and the transformed cells can be destroyed by the immune defense system, but some transformed cells may overcome the immune surveillance resulting in cancer development and progression 3,15,22,23,44 .…”

Nurses, Smoking, and Immunity: A Review

“…A study of young cigarette smokers (age 21–35) who quit smoking showed that NKCA recovery was detectable 31 days after cessation (Meliska et al). In contrast, a prospective study of 6‐month smoking cessation on immunity found a small NKCA increase after cessation among quitters younger than age 65, but not among quitters who were at least 65 years old (Ioka et al, 2001). Immune function recovery through smoking cessation may be influenced by cumulative pack years of smoking before cessation and levels of SHS exposure after cessation (Nakata et al, 2004, 2007), as well as changes in other behavioral factors.…”