Trial of Nonpharmacologic Intervention in the Elderly (TONE). Design and rationale of a blood pressure control trial

Abstract

National and international policy-making organizations advocate nonpharmacologic therapies to reduce blood pressure (BP). However, data to support such recommendations in older persons are virtually nonexistent. The Trials of Nonpharmacologic Intervention in the Elderly (TONE) is a randomized, controlled trial that will test whether weight loss or a reduced sodium (Na) intake or both can maintain satisfactory BP control, without unacceptable side effects, after withdrawal of antihypertensive drug therapy. Medication-treated hypertensives (aged 60 to 80 years) with a systolic BP less than 145 mm Hg and a diastolic BP less than 85 mm Hg who are taking one antihypertensive medication are randomly assigned to one of four groups: (1) weight loss alone, (2) reduced Na intake alone, (3) combined weight loss and reduced Na intake, or (4) usual life-style (control group). Overweight participants are randomized to one of these four groups, while nonoverweight individuals are assigned to either the reduced Na intake or the usual life-style group. The interventions, tailored to the needs of older persons, use behavioral approaches to accomplish intervention-specific goals (weight loss > or = 10 lb, daily Na intake < or = 80 mEqa). Three months after the start of intervention, antihypertensive drug therapy is withdrawn. The primary trial end point is a BP of 150/90 mm Hg or higher, resumption of antihypertensive drug therapy, or the occurrence of a BP-related clinical complication during 2 to 3 years of follow-up. It is anticipated that TONE findings may identify an effective and acceptable nonpharmacologic approach to control hypertension in the increasingly large number of older persons treated with antihypertensive drug therapy.