Physiological and psychological symptoms and predictors in early nicotine withdrawal Holly E.R. Morrell a , Lee M. Cohen b, ⁎ , Mustafa al'Absi c a University of California, San Francisco, United States b Texas Tech University, United States c University of Minnesota School of Medicine, United States Received 26 April 2007; received in revised form 18 December 2007; accepted 18 December 2007 Available online 21 February 2008 Abstract The present study assessed the structure and intensity of the nicotine withdrawal syndrome in 30 (22 male, 8 female) heavy smokers across three experimental conditions: smoking, brief abstinence (3.5 h), and extended abstinence (18 h). Physiological variables (heart rate and blood pressure) and psychological variables (anxious and depressed mood) were examined in terms of symptom validity and as predictors of nicotine withdrawal intensity. As length of abstinence increased, heart rate and blood pressure decreased, and anxious and depressed mood increased. Only anxious and depressed mood were significant individual predictors of withdrawal intensity. The symptom structure of withdrawal did not change over time as abstinence levels increased; each symptom's contribution to nicotine withdrawal intensity remained stable throughout the first 18 h of abstinence. © 2007 Elsevier Inc. All rights reserved. Keywords: Smoking; Nicotine withdrawal; Anxiety; Depression; Heart rate; Blood pressure Smoking cessation or a marked reduction in cigarette consumption produces the nicotine withdrawal syndrome, which is composed of symptoms including irritability, sleep disturbance, impatience, hunger, difficulty concentrating, depression, and anxiety (American Psychiatric Association (APA), 2000). With- drawal is also typically accompanied by physiological changes, such as a decrease in heart rate (al'Absi et al., 2002; Hughes et al., 1994). Many studies suggest that the withdrawal syndrome begins within 1 to 2 days of cessation, peaks within 1 week, and gradually decreases to pre-cessation levels within approximately 4 weeks (Gilbert et al., 2002; Piasecki et al., 1998; Hughes et al., 1994; Hughes, 2007a). Research indicates that the onset of nicotine withdrawal may occur much earlier than originally thought, perhaps within the first 2 to 24 h of abstinence (Hendricks et al., 2006; Hughes et al., 1994; Parrott et al., 1996; Shiffman et al., 2002). However, surprisingly few studies have examined the temporal progression of the withdrawal syndrome within these first 24 h, thus leaving a significant gap in our understanding of nicotine withdrawal (Hendricks et al., 2006). Evidence shows that the time course of the withdrawal syndrome may be an important predictor of relapse following a smoking cessation attempt (al'Absi et al., 2004; Piasecki et al., 1998; Piasecki et al., 2000; Piasecki et al., 2003a, 2003b, 2003c). For example, Piasecki and colleagues found that quitters who experienced an escalation in withdrawal severity over time were more likely to relapse than quitters whose symptoms decreased over time (Piasecki et al., 2003a, 2003b, 2003c). These findings suggest that a greater understanding of the time course of withdrawal is warranted, as it may help researchers and clinicians to develop more effective smoking cessation programs by highlighting which symptoms should be targeted most aggres- sively, and at what point in the cessation process. Such goals necessitate a more complete knowledge of early nicotine withdrawal (i.e., within the first 24 h of smoking cessation), including order of symptom onset and potential symptom stages (Hughes, 2007b). Available online at www.sciencedirect.com Pharmacology, Biochemistry and Behavior 89 (2008) 272 – 278 www.elsevier.com/locate/pharmbiochembeh ⁎ Corresponding author. Texas Tech University, Psychology Department, P.O. Box 42051, Lubbock, TX 79409-2051, United States. Tel.: +1 806 742 3711x236. E-mail address: lee.cohen@ttu.edu (L.M. Cohen). 0091-3057/$ - see front matter © 2007 Elsevier Inc. All rights reserved. doi:10.1016/j.pbb.2007.12.020