Weight loss and risk of hypertension

Message

For moderately overweight people, losing weight and keeping lost weight off can substantially reduce the risk of becoming hypertensive in the future.

Reference

LL Moore et al. Weight loss in overweight adults and the long-term risk of hypertension. Archives of Internal Medicine 2005 165: 1298-1303.


Study

This was an observational study of 5000 surviving members of the Framingham study. It looked at people aged 40-59 years and 50-65 years who had initially overweight with a BMI of over 25, and who either had stable weight, or had lost weight over the next four years. The analysis was according to amount of weight lost and by whether the weight loss was sustained. Incidence of hypertension over four years was from the number of incident cases of high blood pressure.

Results

There were 623 overweight middle aged adults and 605 overweight older adults. Mean baseline BMI was about 27-29. Just over half were men, and about half the adults smoked.

In both younger and older adults, the four-year incidence of hypertension was substantially reduced by weight loss. The more weight was lost, the lower the risk of hypertension (Figure 1). This was statistically significant for older adults who lost more than 6.8 kg.

Figure 1: Effect of amount of weight lost on four year hypertension risk

Sustaining weight loss was also important. Figure 2 shows the results according to any weight loss, and according to whether the weight was sustained or not over the four years. Sustained weight loss, particularly in older adults, resulted in a substantial and statistically significant reduction of four year risk of hypertension.

Figure 2: Effect of sustained weight loss on four year risk of hypertension

Comment

Losing weight is hard. Taking antihypertensive medicines might just be harder. Weight loss can reduce the chance of becoming hypertensive, and in this group of mildly overweight people it was important. Getting their weight down to about a BMI of 25 to one of between 25 and over 30 made a difference. These were not grossly overweight people. Keeping it off helped.

Only about 1 person in 10 could achieve a weight loss of more than 6.8 kg (about 12 lbs). Only about One person in four could lose at least 1.8 kg and keep it off. Not many could have lost a lot of weight and kept that loss of weight off, but in those the reduction in risk of hypertension was probably quite large.