Attention deficit hyperactivity disorder (ADHD) is characterized by inattention, impulsivity, and hyperactivity that are frequently treated with stimulant medications such as Ritalin. Many people with ADHD smoke. The smoking prevalence rates are estimated to be 40% in adults with ADHD compared to 20% in the general population. People with ADHD have also more difficulty to quit smoking. Only 29% of smokers with ADHD quit smoking compared to 48.5% of smokers in the general population. Nicotine is a stimulant, which may have properties similar to stimulant medications (e.g., Ritalin) used to treat ADHD. Nicotine may increase attention and reduce hyperactivity and impulsivity and, thus, may regulate behavior in individuals with ADHD. Alleviating the symptoms of ADHD and increasing cardiovascular activity through smoking may mimic the effects of stimulant medications and can be a form of self-medication.

The major objective of the study was to examine the effects of nicotine on ADHD symptoms, moods, and cardiovascular activity. The study investigated the effects of nicotine patches on behavioral regulation in adult smokers and nonsmokers with ADHD. Smokers and nonsmokers with ADHD participated in two conditions: (1) nicotine patch and (2) placebo patch. During each condition, symptoms, moods, and side effects were assessed for 2 days during waking hours. An electronic handheld diary, programmed to prompt the participant twice per hour, recorded ADHD symptoms (e.g., difficulty concentrating, impulsivity, etc.), negative moods (e.g., anger, stress), and nicotine side effects (nausea, dizziness). Heart rate and blood pressure were recorded with lightweight ambulatory monitors to indicate cardiovascular activity. Results provided information about the effects of nicotine patches on behavioral regulation in adult smokers and nonsmokers with ADHD.

The inclusion of nonsmokers was important to clarify whether the effects of nicotine on smokers was due to smoking withdrawal. The findings help explain the increased smoking prevalence rates and reduced quit rates associated with ADHD. Knowledge about nicotine's effects on behavioral regulation can help to develop successful smoking cessation programs for individuals with ADHD. The findings on cardiovascular activity may help determine the potential risk for cardiovascular disease in smokers and nonsmokers with ADHD. The study contributed to understanding nicotine's effects on behavioral regulation in a highly vulnerable population such as people with ADHD.

Inclusion Criteria:

• An age of 18 to 45 years
• A history of ADHD
• Current diagnosis of ADHD according to clinical criteria
• Being a smoker who smokes at least 10 cigarettes per day with 0.5 mg of nicotine per cigarette; OR
• Being a nonsmoker who has been abstaining from smoking and other nicotine products for the last 2 years

Exclusion Criteria:

• Treatment for any chronic illness such as heart disease, irregular heartbeat, high blood pressure, diabetes, skin allergies or skin diseases, including psoriasis or eczema, even if currently controlled by medication
• Current pregnancy, as measured by a pregnancy test (Clear Blue Easy, Unipath, Bedford, UK), or planning to become pregnant within the next 6 months. These individuals will not be included as the nicotine patch may cause harm to the unborn fetus
• Nursing mothers, or women who have breastfed within the last 12 months
• Non-English speaking people, because the majority of measurements used in the study have not been validated in languages other than English
• Current major depressive episode according to clinical criteria
• Concurrent psychiatric psychoactive medication within the past 12 months
• Active substance abuse within the past 12 months