February 1, 2000Open Access
View Full PaperLong-Term Effects of Weight Loss and Dietary Sodium Reduction on Incidence of Hypertension
Key Result
An 18-month weight loss intervention significantly reduced the 7-year incidence of hypertension compared to usual care (OR 0.23; 95% CI 0.07-0.76; P=0.02), whereas sodium reduction did not (P=0.37).
Study Design
Type
RCT (n=181)
Blinding
Single-blind
Randomization
Randomized
Multicenter
No
Structured PICO
Does an 18-month lifestyle modification intervention (weight loss or dietary sodium reduction) prevent incident hypertension in adults with high-normal diastolic blood pressure?
P
Population
181 men and women, aged 30 to 54 years, with baseline diastolic blood pressure of 80 to 89 mm Hg and systolic blood pressure <160 mm Hg, who participated in the Trials of Hypertension Prevention, phase 1, in Baltimore, Md.
I
Intervention
18-month lifestyle modification interventions aimed at either weight loss or dietary sodium reduction
C
Comparator
Usual care control group
O
Outcome
Incident hypertension (defined as systolic BP ≥160 mm Hg and/or diastolic BP ≥90 mm Hg and/or treatment with antihypertensive medication) at 7 years follow-upcomposite
An 18-month weight loss intervention significantly reduces the long-term (7-year) incidence of hypertension in adults with high-normal diastolic blood pressure.
Main Result
Effect estimate: OR 0.23 (95% CI 0.07 to 0.76)
Absolute Event Rate: 18.9% vs 40.5%
p-value: p=0.02
Abstract
To examine the long-term effects of weight loss and dietary sodium reduction on the incidence of hypertension, we studied 181 men and women who participated in the Trials of Hypertension Prevention, phase 1, in Baltimore, Md. At baseline (1987 to 1988), subjects were 30 to 54 years old and had a diastolic blood pressure (BP) of 80 to 89 mm Hg and systolic BP or =160 mm Hg and/or diastolic BP > or =90 mm Hg and/or treatment with antihypertensive medication during follow-up. Body weight and urinary sodium were not significantly different among the groups at the posttrial follow-up. After 7 years of follow-up, the incidence of hypertension was 18.9% in the weight loss group and 40.5% in its control group and 22.4% in the sodium reduction group and 32.9% in its control group. In logistic regression analysis adjusted for baseline age, gender, race, physical activity, alcohol consumption, education, body weight, systolic BP, and urinary sodium excretion, the odds of hypertension was reduced by 77% (odds ratio 0.23; 95% confidence interval 0.07 to 0.76; P=0.02) in the weight loss group and by 35% (odds ratio 0.65; 95% confidence interval 0.25 to 1.69; P=0.37) in the sodium reduction group compared with their control groups. These results indicate that lifestyle modification such as weight loss may be effective in long-term primary prevention of hypertension.