Salt restriction and increased insulin production in hypertensive patients.
The present study was performed to evaluate glucose metabolism, serum lipids and sympathetic activity during 12 weeks of a moderate salt restricted diet in hypertensive patients. The study was designed as a pre-test-post-test study. All patients from a controlled trial evaluating self-monitoring of urine chloride concentration as a remedy for enhancing diet compliance and blood pressure effect were included. Twenty male patients and 14 female patients with essential hypertension (mean age 53 years) were randomized to a self monitoring diet group and a diet only group. They were exposed to a moderately salt restricted diet during 12 weeks. Fasting serum insulin C-peptide, glucose, HbA1c, total cholesterol, LDL-cholesterol, HDL-cholesterol and triglycerides were measured along with 24 h urine excretion of adrenaline, noradrenaline and vanillylmandelic acid (VMA). As a result, insulin C-peptide increased by 40% (p = 0.0001) whereas glucose rose by 6% (p = 0.02). Total cholesterol, LDL-cholesterol and HDL-cholesterol concentration were reduced by 6% (p = 0.001), 12% (p = 0.008) and 11% (p = 0.004) respectively. HbA1c, serum triglycerides, total/HDL-cholesterol ratio, urine catecholamines and VMA were unchanged during the trial. It is concluded that salt restriction may increase insulin resistance in hypertensive patients.
Meland
E
E
Department of Public Health and Primary Health Care, Division for General Practice, Bergen, Norway.
Laerum
E
E
Aakvaag
A
A
Ulvik
R J
RJ
D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000378:metabolism*; D004039:Diet, Sodium-Restricted; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D006973:Hypertension / Q000178:diet therapy* / Q000378:metabolism; D007328:Insulin / Q000096:biosynthesis*; D008055:Lipids / Q000097:blood*; D008297:Male; D008875:Middle Aged; D012648:Self Care; D013564:Sympathetic Nervous System / Q000503:physiopathology*
D001786:Blood Glucose; D007328:Insulin; D008055:Lipids