Introduction:
The aim of the study was to find out if the extreme number of cigarettes smoked per day by the patients with tobacco dependence corresponds with their clinico-genetic characteristics. Clinical and genetic study was conducted in 50 patients with high level of tobacco dependence (K. Fagerstroem). They were divided into 2 groups: the main group (n=24) with an extreme number of cigarettes - ≥ 40 cigarettes/day (47±5,1), age 48.5±2.5 years, and the control group (n=26) – up to 20 cigarettes/day(25.2±2.6, P <0.01), age 45.3±2.4 years. All the patients of the main group had pharmacological resistance to Varenicline, Nicorette, Citizine and never stopped smoking. In the control group the patients had several affective quit attempts. The genetic study included identification of polymorphism (variations) of the gene nicotinic receptor rs578776 and COMT gene rs4680 in all the patients.

Results:
Clinical evaluation of Craving for Smoking syndrome: 3.75±0.96 (of 4 balls maximum) in the main group; 1.670,083 balls – in the control. Emotional-personality features, examined by Toronto Alexithymics test: the average index value of alexithymia in the main group significantly surpassed the similar indicator of the control group (77.0±2, 1 compared to 66.1±1.5 p<0.01). Homozygotes for valine (COMT) in the main group - 22 (9.6%), in the control - 2 (7.7% - Χ2=5.78, p=0,0109). Rs578776 polymorphism: the main group - 21 (87.5%), the control-3 (11.5%).

Conclusions:
The patients with the extreme number of cigarettes smoked have the great difference in genetics background, clinical features and emotional-personal properties compared to the persons with “normally hard” tobacco addiction, and need individualized therapy approach.

Funding Statement:
Supported by the grant from the Russian humanitarian scientific Fund № 15-06-10839