Current issues of ACP Journal Club are published in Annals of Internal Medicine


Therapeutics

Weight reduction, dietary sodium restriction, and an increase in exercise reduced mildly raised blood pressure in older patients

ACP J Club. 1992 Nov-Dec;117:79. doi:10.7326/ACPJC-1992-117-3-079


Source Citation

Applegate WB, Miller ST, Elam JT, et al. Nonpharmacologic intervention to reduce blood pressure in older patients with mild hypertension. Arch Intern Med. 1992 Jun;152:1162-6.


Abstract

Objective

To evaluate a combination of weight reduction, sodium restriction, and physical activity for reducing blood pressure (BP) in elderly persons with mild hypertension.

Design

6-month randomized controlled trial.

Setting

Volunteers were recruited to a university preventive medicine clinic through community advertising and BP screening programs.

Participants

Men and women aged 60 to 85 years, with diastolic (D) BP, 85 to 100 mm Hg; body weight ≥ 115% of ideal; adequate mental and physical health and vision (20/60 or better); and willingness to participate in lifestyle change programs were eligible. Persons with a history of recent myocardial infarction or stroke; serious cardiovascular or chronic illness; diabetes; elevated serum creatinine, glucose, or cholesterol levels; and those taking medications that might affect BP were excluded. 56 of 300 persons screened (mean age, 65 y; women, 55%, white, 62%) were randomized; 47 (84%) completed the trial.

Interventions

28 persons were assigned to nonpharmacologic interventions and 28 to no treatment. Mean DBP was measured and all BP-lowering medications were stopped during a 3- to 8-week baseline period. Participants attended weekly, then monthly, counseling sessions aimed at a weight loss of 4.5 kg, reduction of sodium intake to 1400 mg/d, and increased activity (120 min/wk of mostly slow walking). Patients who took antihypertensive medication or had systolic (S) BP > 199 or DBP > 105 mm Hg on 2 visits left the trial.

Main outcome measures

Change in BP, weight, and urine sodium excretion were measured with participants' assignment masked.

Main results

Mean baseline DBP fell by 6.8 mm Hg after 6 months from 86.5 mm Hg in the intervention group compared with a reduction of 1.9 mm Hg from 88.4 mm Hg for the control group (P = 0.003). SBP also fell more for the intervention group (8.7 fall from 142.6 mm Hg and 4.5 fall from 144.5 mm Hg, for the groups, respectively; P = 0.02). The greatest change occurred during the first 2 months and was maintained. The intervention group lost weight (mean 2.1 kg loss vs 0.3 kg gain; P < 0.001), but urine sodium excretion was similar for the groups. 1 person in the intervention group developed DBP over the trial limit.

Conclusion

Elderly men and women reduced mildly raised blood pressure without antihypertensive medication through weight reduction, dietary sodium restriction, and an increase in exercise.

Source of funding: Not stated.

For article reprint: Dr. W.B. Applegate, 66 North Pauline, Suite 232, Memphis, TN 38105, USA.


Commentary

Using a multifaceted, nonpharmacologic approach to treat mildly increased blood pressure, Applegate and colleagues have shown that this strategy may have potential as first-line treatment for an older population aged 60 to 85 years with very mildly elevated blood pressure. Nonpharmacologic treatment has many intrinsic advantages, such as lower cost and fewer adverse effects, when compared with antihypertensive medication. Because of the limited sample size and restrictive inclusion criteria, generalization of these results is limited to a relatively healthy, older, mildly overweight population, with no evidence of major cardiovascular risk factors such as increased serum cholesterol or glucose. Of the 300 age-eligible persons screened, only 18.7% met all criteria and agreed to participate.

It is important to note that this study used a combined intervention of which only 1 component, body weight, changed significantly during the study when the intervention and control groups were compared. Dietary sodium intake decreased in both groups, and similar levels were achieved at the end of the study. Hours of physical exercise increased in the intervention group but were not measured in the control group. As a result, it is impossible to determine if 1, 2, or all 3 interventions are required to lower blood pressure. Because simple lifestyle changes are the easiest to accomplish and the best maintained, particularly in older populations, studying the independent effects of a broad range of nonpharmacologic interventions would be important in future studies. Although weight loss, sodium restriction, and exercise may lower blood pressure, relaxation therapy and dietary supplementation with potassium, calcium, and fish oil should be considered.

Cynthia D. Morris, PhD
Oregon Health Sciences UniversityPortland, Oregon, USA

Cynthia D. Morris, PhD
Oregon Health Sciences University
Portland, Oregon, USA