1.a.(1). Lifestyle
Trials in Hypertensive Patients
Evidence Statement: Weight loss produced by lifestyle
modifications reduces blood pressure in overweight hypertensive patients.
Evidence Category A. |
Rationale: A1987
meta-analysis (381) covering five of the
acceptable studies (351, 352, 356-358) in
hypertensive patients concluded that weight loss accomplished by dietary
interventions significantly lowered blood pressure. In hypertensive patients,
10 kg (22 lb) of weight loss was associated with an average reduction of 7 mm
Hg systolic and 3 mm Hg diastolic blood pressure compared with controls (381).
Since publication of this
meta-analysis in 1987, almost all relevant studies have reported that weight
loss reduces blood pressure or the need for medication in hypertensive patients
(346-348, 350, 352-361):
- The Trial of
Antihypertensive Interventions and Management (TAIM), conducted in hypertensive
individuals not taking medication for 6 months, reported that, compared with
controls, a mean net weight reduction of 4.7 kg (10.4 lb) reduced systolic and
diastolic blood pressure by 2.8 mm Hg and 2.5 mm Hg, respectively (355); the effects on blood pressure were
equivalent to drug therapy among those participants who lost 4.5 kg (9.9 lb) or
more (360).
- One study in older (age 60
to 80 years) hypertensive adults whose blood pressure medication was withdrawn
(Trial of Nonpharmacologic Interventions in the Elderly, TONE) showed that
after 2 years, mean net weight loss of nearly 4 kg (9 lb) resulted in more
participants free of trial endpoints (occurrence of high blood pressure,
resumption of blood pressure medication, or occurrence of a
cardiovascular-clinical complication [39.2 percent versus 26.2 percent]) (382). Furthermore, blood pressure control was
similar for men and women and for African Americans and whites (353).
- In other studies of
primarily middle-aged hypertensive adults, compared with controls, weight loss
significantly reduced a return to hypertension medication at 1 year (354) and at 4 to 5 years (348, 359).
- The Multiple Risk Factor
Intervention Trial, which recruited 12,866 high risk men, 30 percent of whom
had hypertension, delivered an integrated intervention addressing several
lifestyle behaviors and included weight loss as an important component.
Significant reductions in systolic and diastolic blood pressure were found over
6 years compared with the usual care group and were directly related to weight
loss: 1 kg (2.2 lb) of weight loss was associated with a reduction of 0.4 mm Hg
systolic and 0.3 mm Hg diastolic blood pressure in men not taking
antihypertensive medications. The effect was slightly lower for men taking
antihypertensive medications.
- Only one RCT conducted in
hypertensive patients reported no significant change in blood pressure despite
weight loss of 3.3 kg (7.3 lb) (351).
- Another study conducted in
hypertensive individuals suggested that weight loss reduced blood pressure only
when sodium intake was also reduced (349).This finding was not consistent with a
prior study of hypertensive patients (358)
and has not been corroborated in subsequent larger trials conducted in
nonhypertensive individuals (378,
379).
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