Preventing Weight Gain and Controlling Blood Pressure During Smoking Cessation in Hypertensive Smokers

BACKGROUND:

High blood pressure (BP), or hypertension, is a major risk factor for cardiovascular morbidity and mortality. Hypertension is associated with an elevated risk for several cardiovascular complications, including coronary heart disease, peripheral vascular disease, congestive heart failure, and stroke, as well as an increased risk for renal disease. Although there have been significant advances in the detection and treatment of high BP, approximately one in four adults in the United States is hypertensive. Cigarette smoking accounts for more than 400,000 premature deaths each year in this country alone, making it the leading cause of morbidity and mortality. Evidence from several epidemiological studies has demonstrated that, at any level of BP, smoking substantially increases the risk for all cardiovascular complications associated with hypertension. While cigarette smoking and hypertension both increase the risk of cardiovascular disease, these two risk factors act synergistically to produce a greater risk than their combined independent effects. Despite the considerable health risks, smoking among people with hypertension is very common, with a prevalence approaching that observed among those with normal BP. Unfortunately, although quitting smoking is especially important for patients with high BP, smoking cessation produces a nontrivial weight gain, averaging 5 kg, which may exacerbate hypertension in many patients with the disorder. Several studies have documented significant elevations in BP following smoking cessation, as well as increases in the prevalence of hypertension after quitting smoking. As such, it is important to develop effective interventions that assist in quitting smoking and preventing weight gain.

DESIGN NARRATIVE:

The objective of the trial is to recruit 750 smokers with Stage 1 hypertension or prehypertension (based on JNC VII criteria). The trial will provide all participants with a brief, validated, combined behavioral and pharmacologic smoking cessation intervention. Additionally, the study will randomly assign participants who are abstinent from smoking upon completing the cessation intervention to either a 12-week weight management and BP control program or self-help materials targeting lifestyle modification. The primary endpoint is change in BP among quit smokers at a one-year follow-up. Secondary endpoints include changes in body weight, dietary intake, urinary sodium excretion, physical activity, and relapse to smoking. Exploratory endpoints include changes in hypertensive status (e.g., movement from prehypertensive to hypertensive by JNC VII criteria) and changes in BP medication status. This is a multi-site clinical trial, with study locations in Rochester, Minnesota, and Iowa City, IA. The Rochester, MN site is currently closed for recruitment.

Inclusion criteria

• Smoke at least 5 cigarettes/day (or have quit within the last 6 weeks to enter the study for the weight gain prevention and BP control interventions)
• Pre-hypertensive or Stage I hypertension (systolic BP from 120 to 159 and/or diastolic BP from 80 to 99 mm Hg). Antihypertensive medications are not criteria for exclusion provided that BP is not over 160/100 mm Hg)
• Access to a telephone

Exclusion criteria

• History of unstable cardiovascular disease, including myocardial infarction, stroke, and unstable angina within three months of study start
• Coronary artery bypass grafting or angioplasty/stent within three months of study start
• Cardiac dysrhythmia treated with anti-arrhythmia medication, except stable atrial fibrillation
• Untreated hyperthyroidism or pheochromocytoma
• History of congestive heart failure (NYHA Class III or IV)
• ECG evidence of 2nd or 3rd degree atrioventricular block
• Uncontrolled or Stage II Hypertension as defined as BP consistently above 160/100 mm Hg
• History of severe liver or kidney failure
• Current substance abuse (includes alcohol use in excess of 21 drinks a week)
• Presence of an unstable psychiatric condition
• Severe chronic obstructive pulmonary disease
• Symptomatic peripheral vascular disease
• Pulmonary hypertension with shortness of breath
• Congenital or valvular heart disease with shortness of breath
• Current use of a medication that may interfere with primary study endpoints or that may increase the risk of side effects from study medication that cannot be discontinued
• Pregnant or plans to become pregnant within the next year
• Planning to move out of the area or travel extensively during the intervention
• Any medical condition that would preclude any additional changes in diet
• Unable to further modify physical activity routine
• Cannot engage in moderate intensity exercise (e.g., walking)