According to the World Health Organization, "Greater nicotine dependence has been shown to be associated with lower motivation to quit, difficulty in trying to quit, and failure to quit, as well as with smoking the first cigarette earlier in the day and smoking more cigarettes per day." The WHO estimates that there are 1.1 billion smokers globally.WHO global report on trends in prevalence of tobacco smoking 2000–2025, second edition. Geneva: World Health Organization. http://apps.who.int/iris/bitstream/handle/10665/272694/9789241514170-eng.pdf Of the 34 million smokers in the US in 2018, 74.6% smoked every day, indicating the potential for some level of nicotine dependence. There is an increased frequency of nicotine dependence in people with anxiety disorders.
