All the measures were taken at baseline assessment. Participants completed a self-administered questionnaire covering their smoking habits, duration of diabetes mellitus, diet, alcohol intake,
physical activity level, and depressive symptoms. Based on smoking status, patients were classified as never smokers, past smokers, or current smokers. Never smokers were defined as those who had never smoked. Past smokers were defined as those who smoked before but did not smoke at the time of study registration. Current smokers were further subdivided by number
of cigarettes per day (