The objective of the Trial of Antihypertensive Intervention Management (TAIM) was to determine the efficacy of dietary management and/or drug therapy, namely thiazide-like diuretics or a beta-blocker, in the control of mild hypertension. Additionally, the Continuation of the Trial of Antihypertensive Intervention Management (COTAIM) tested the effects of long-term weight reduction, and sodium/potassium changes added to weight reduction, as well as the original drug treatment, on the failure rate of blood pressure control.

BACKGROUND:

The Trial of Antihypertensive Intervention Management was an extension of the NHLBI-supported Dietary Intervention Study of Hypertension (DISH) which concluded in March 1984 and showed that either weight reduction or sodium restriction diets reduced relapse rates of hypertensives who had received long-term drug treatment and then been withdrawn from drugs. TAIM was initiated in April 1984 and continued for four years at three centers and added to DISH the art of evaluating combined drug and dietary treatments. COTAIM was continued at three clinical sites in July 1988. Analysis of COTAIM results continued through November 1994 under grant R01HL40072.

DESIGN NARRATIVE:

TAIM patients were randomly assigned to one of three diets and to one of three drug regimens. The dietary interventions consisted of a weight loss program, sodium reduction with increased potassium intake, or no change in diet. The drug regimen consisted of a beta-blocker (atenolol), a thiazide-like diuretic (chlorthalidone), or placebo. The major endpoint was change in diastolic blood pressure after six months of intervention. Individuals who did not reach goal blood pressure after six months received additional drugs. Other endpoints included total risk factor score change, psychological function, and lifestyle change.

COTAIM consisted of two studies with a total of 600 subjects. COTAIM I compared the TAIM weight loss group to a randomly selected half of the usual diet group. The primary endpoint of COTAIM I was the degree of control of blood pressure on initial TAIM therapy between TAIM baseline and the end of COTAIM, a five year period.

COTAIM II added a weight loss regimen both to the sodium restriction/potassium supplementation groups and to the other half of the usual diet group. The primary outcome was control of blood pressure on initial TAIM therapy between COTAIM baseline and the end of COTAIM, a two-year period.

• Cardiovascular Diseases
• Heart Diseases
• Hypertension
• Vascular Diseases

• Behavioral: diet, reducing
• Behavioral: diet, sodium-restricted
• Drug: chlorthalidone
• Drug: atenolol

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• Langford HG, Rockhold RW, Wassertheil-Smoller S, Oberman A, Davis BR, Blaufox MD. Effect of weight loss on thiazide produced erectile problems in men. Trans Am Clin Climatol Assoc. 1989;101:190-4.
• Oberman A, Wassertheil-Smoller S, Langford HG, Blaufox MD, Davis BR, Blaszkowski T, Zimbaldi N, Hawkins CM. Pharmacologic and nutritional treatment of mild hypertension: changes in cardiovascular risk status. Ann Intern Med. 1990 Jan 15;112(2):89-95.
• Langford HG, Davis BR, Blaufox D, Oberman A, Wassertheil-Smoller S, Hawkins M, Zimbaldi N. Effect of drug and diet treatment of mild hypertension on diastolic blood pressure. The TAIM Research Group. Hypertension. 1991 Feb;17(2):210-7.
• Wassertheil-Smoller S, Blaufox MD, Oberman A, Davis BR, Swencionis C, Knerr MO, Hawkins CM, Langford HG. Effect of antihypertensives on sexual function and quality of life: the TAIM Study. Ann Intern Med. 1991 Apr 15;114(8):613-20.
• Langford HG. Sodium-potassium interaction in hypertension and hypertensive cardiovascular disease. Hypertension. 1991 Jan;17(1 Suppl):I155-7.
• Wassertheil-Smoller S, Blaufox MD, Oberman AS, Langford HG, Davis BR, Wylie-Rosett J. The Trial of Antihypertensive Interventions and Management (TAIM) study. Adequate weight loss, alone and combined with drug therapy in the treatment of mild hypertension. Arch Intern Med. 1992 Jan;152(1):131-6.
• Davis BR, Oberman A, Blaufox MD, Wassertheil-Smoller S, Hawkins CM, Cutler JA, Zimbaldi N, Langford HG. Effect of antihypertensive therapy on weight loss. The Trial of Antihypertensive Interventions and Management Research Group. Hypertension. 1992 Apr;19(4):393-9.
• Wassertheil-Smoller S, Oberman A, Blaufox MD, Davis B, Langford H. The Trial of Antihypertensive Interventions and Management (TAIM) Study. Final results with regard to blood pressure, cardiovascular risk, and quality of life. Am J Hypertens. 1992 Jan;5(1):37-44.
• Blaufox MD, Lee HB, Davis B, Oberman A, Wassertheil-Smoller S, Langford H. Renin predicts diastolic blood pressure response to nonpharmacologic and pharmacologic therapy. JAMA. 1992 Mar 4;267(9):1221-5.
• Davis BR, Blaufox MD, Oberman A, Wassertheil-Smoller S, Zimbaldi N, Cutler JA, Kirchner K, Langford HG. Reduction in long-term antihypertensive medication requirements. Effects of weight reduction by dietary intervention in overweight persons with mild hypertension. Arch Intern Med. 1993 Aug 9;153(15):1773-82.
• Wylie-Rosett J, Wassertheil-Smoller S, Blaufox MD, Davis BR, Langford HG, Oberman A, Jennings S, Hataway H, Stern J, Zimbaldi N. Trial of antihypertensive intervention and management: greater efficacy with weight reduction than with a sodium-potassium intervention. J Am Diet Assoc. 1993 Apr;93(4):408-15.
• Davis BR, Oberman A, Blaufox MD, Wassertheil-Smoller S, Zimbaldi N, Kirchner K, Wylie-Rosett J, Langford HG. Lack of effectiveness of a low-sodium/high-potassium diet in reducing antihypertensive medication requirements in overweight persons with mild hypertension. TAIM Research Group. Trial of Antihypertensive Interventions and Management. Am J Hypertens. 1994 Oct;7(10 Pt 1):926-32.
• Wassertheil-Smoller S, Davis BR, Breuer B, Chang CJ, Oberman A, Blaufox MD. Differences in precision of dietary estimates among different population subgroups. Ann Epidemiol. 1993 Nov;3(6):619-28.

Men and women, ages 21 to 65, with mild hypertension in the range of 90 to 100 mm Hg diastolic blood pressure.

Subjects were obese (110-150 percent of ideal weight).