Low daily salt intake tied to improved BP control
Reducing daily salt intake is associated with improved blood pressure (BP) levels in patients with hypertension, according to a study presented at APCH 2017.
The researchers analysed 10,547 patients with hypertension (mean age 64.5 years, 70.8 percent male, mean BP 130.9/78.2 mm Hg) who were taking antihypertensive medications and visited the hospital for a physical check-up over a 6-year period. Participants were divided into three groups according to the number of prescribed antihypertensive drugs: group 1 (n=5,469; one drug), group 2 (n=3,861; two drugs), and group 3 (n=1,217; ≥3 drugs). Spot urine method was used to estimate salt intake, and patients were assessed for up to 6 years. [APCH 2017, abstract 4665]
Overall, BP levels reduced from 132.9/80.1 to 129.9/77.1 mm Hg and achievement of target BP (<140/90 mm Hg) increased from 65.4 to 76.4 percent over the study duration in all groups.
Individuals with a BP level below target value (<140/90 mm Hg) were more likely to achieve a higher rate of salt restriction (<6 grams daily) compared with those who had a BP level above the target value (3.9 percent vs 2.5 percent, 2.9 percent vs 2.3 percent, and 2.6 percent vs 1.4 percent in groups 1, 2, and 3, respectively).
Individuals who achieved salt restriction were more likely to reach the target BP than those who did not achieve salt restriction (overall, 82.0 percent vs 72.5 percent; 78.4 percent vs 74.1 percent, and 84.8 percent vs 74.7 percent in groups 1, 2, and 3, respectively).
However, achievement rate of salt restriction reduced with the number of antihypertensive drugs prescribed (3.5, 2.9, and 2.4 percent in groups 1, 2, and 3, respectively).
“The control of BP in individuals with antihypertensive medications was improved in the last 6 years,” said lead author Dr Hiroyuki Takase from the Department of Internal Medicine at Enshu Hospital in Hamamatsu, Japan. “However, salt restriction has not been successfully achieved especially in hypertensive patients with multiple antihypertensive medications.”“Excess salt intake may induce resistance to antihypertensive treatment and, thus, increases the number of antihypertensive drugs for BP control,” Takase added.