Effect on smoking cessation of silver acetate, nicotine and ordinary chewing gum. Influence of smoking history.

In a randomized smoking cessation study 211, 203 and 82 persons were supported with nicotine, silver acetate and ordinary chewing gum, respectively. After 26 weeks there was no overall difference in number of abstainers between treatments. Participants were divided into subsets with low and high weighted packyears consumption (WPY) which modifies tobacco consumption by nicotine content. Abstainer rates in the total population controlled for treatment decreased with increasing WPY (P less than 0.005). In participants with low WPY abstainer rate was higher in the silver acetate group compared to the nicotine (P less than 0.0005) and ordinary (P less than 0.05) chewing gum groups. Nicotine chewing gum was more effective than silver acetate (P less than 0.05) and ordinary (P less than 0.05) chewing gum in smokers with high WPY. Ratings on some inconveniences experienced during earlier attempts to quit smoking influenced the ability to break the habit but had no influence on chewing gum effects. This study indicated that through consideration of smoking history it should be possible to individualize pharmacological support to smokers wanting to quit, with silver acetate chewing gum most effective for smokers with a low WPY and nicotine chewing gum most effective for smokers with a high WPY.