Nicotine dependence is a maladaptive pattern of tobacco smoking with withdrawal symptoms like other drug addictive disorders. Many life behaviors may change cigarettes daily consumption or smoke state (4). People with healthy behaviors has lower nicotine dependence ,such as exercising, sleep enough time(8, 16). Previous studies demonstrate that unhealthy lifestyles ,including sleep duration (10, 16), caffeine drink consumption(5, 17), alcohol dependence(6, 7), mental activities (gambling(18, 19), play video games(20), overtime working(21)) increase cigarettes consumption and turn ex-smokers or non-smokers into smokers. However, smokers with several different lifestyles is common in their daily life and there are few studies investigate the influence of combined lifestyles on high nicotine dependence. To our knowledge, our research is the first to study revealing the relationship between healthy or unhealthy combined lifestyles and the risk of high ND. Importantly, we revealed that interaction of mental activities after dinner, caffeine drink and sleep time less than 8 hours greatly increased the risk of high ND.
During night without smoking, decrease of nicotine level can recover nicotinic-acetylcholine receptors. It may contribute to development of withdrawal symptoms in the morning when caving for cigarettes(22). Sleep duration further decreases positive mood and increases negative mood(10).Dopamine caused by the calming effect of nicotine relieve this bad mood(23).Therefore, smokers with high nicotine dependence will considered the first few cigarettes as the most pleasurable of the day. We can also understand sleep duration may increase the risk of high nicotine dependence.
Mental activities after dinner(13) (including gambling, overtime work, play video games, studying or other mental thinking activities) and smoking may be related to environment factor, such as colleagues, classmates, gamblers and video game patters. Moreover, tobacco was used to make dopamine to get rid of anxious and cope with stress to focus attention in these situations(24–26).Furthermore, coffee or caffeine drink is also the choice for dealing with tiredness in that some low-cost addictive substance are available anywhere and anytime. The prevalence of drinking caffeine beverage and smoking together will happen during mental activities after dinner or morning without enough sleep time. Caffeine withdrawal symptoms increased difficulties in smoking cessation(17).So,synergistict effects of mental activities after dinner, caffeine drink, sleep duration increase the risk of high nicotine dependence.
Our data proved that healthy lifestyles can’t help decrease the risk of high ND. This result is different than previous studies that smokers with exercises have lower nicotine dependence and lower tobacco consumption (8, 9).The main reason of differences is that we chose all range of age smokers with exercise more than 3 times a week and each time more than 30 minutes. This inclusion criteria can be wildly used in all high nicotine dependent smokers. And we also proved that afternoon snap didn’t decrease the risk of high nicotine dependence. Short breaks, such as a nap, relieve stress and reduce brain fatigue during workdays. Some smokers who need nicotine for getting rid of tiredness will decrease cigarettes consumption in that enough rest help brains to focus attention. There are few studies showed the relationship between nap with nicotine dependence. Therefore, we draw a suggestion that smokers who come to clinic for cessation help with high nicotine dependence should fully consider individualized treatment no matter with healthy or unhealthy lifestyles instead of avoiding unhealthy life behaviors or developing healthy lifestyles only.
In the future, standards of unhealthy life behaviors, such and cups of caffeine drink and the sort of mental activities can obviously increase nicotine dependence in smokers. Healthy life behaviors, such as nap, should be more investigated the mechanism underlying nicotine dependence.