Dietary Fatty Acid Ups Hypertension Risk in Diabetic Patients

A cross-sectional study has found that the correlation between dietary fatty acid and hypertension varies significantly based on the presence of diabetes.

“The metabolic products of n-6 fatty acids include those that control blood pressure, such as prostaglandin and thromboxane, and that differ depending on the extent of glucose tolerance,” the researchers explained.

For the study, researchers reviewed results from a self-administered questionnaire from March 2014 through January 2016. Of 2,160 potential participants who received surveys, 1,987 returned them, of whom 790 completed both the questionnaire and a medical exam. Patients receiving treatment for diabetes, dyslipidemia, coronary artery disease, or cerebrovascular disease were not included. The final analysis included data on 633 Japanese patients aged 40 years or older. Patients on antihypertensive medication or with a blood pressure of 140/90 mmHg were considered hypertensive.

“There have been conflicting reports of the relationship between dietary intake of n-6 fatty acids and risk of hypertension,” said study author Hiroyuki Nakamura in a press release. “Metabolites of n-6 fatty acids can lower blood pressure in a manner influenced by blood glucose levels. Therefore, we suspected that the relationship between dietary intake of n-6 fatty acids and risk of hypertension might be affected by glucose tolerance, which is impaired in patients with diabetes.”

Different Outcomes for Diabetic Versus Healthy Patients

Among the 633 patients (mean age, 61 years), 47% were male, 21% were smokers, and 55% exercised; 55.3% of the cohort had hypertension. Researchers observed an inverse relationship between a diet high in n-6 fatty acids and hypertension in patients whose HbA1c values were less than 6.5% (odds ratio [OR], 0.857; 95% confidence interval [CI], 0.744 to 0.987). Meanwhile, for diabetic patients (HbA1c values greater than 6.5%), a greater intake of n-6 fatty acids sharply increased their hypertension risk (OR, 3.618; 95% CI, 1.019 to 12.84). Hypertension outcomes were similar when looking specifically at linoleic acid (nondiabetic patients, OR = 0.858; 95% CI = 0.744 to 0.991; diabetic patients, OR = 0.858; 95% CI = 0.744 to 0.991).

The study is the first to unearth a relationship between n-6 fatty acids intake and diabetes, according to lead study author Haruki Nakamura.

“A previous meta-analysis showed that higher intake of a diet rich in linoleic acid (the main fatty acid in the n-6 fatty acids class) was significantly associated with higher risks of death from all causes, cardiovascular disease, and coronary heart disease in subjects with cardiovascular disease,” Nakamura said. “Therefore, our results indicate that n-6 fatty acid intake may have no cardiovascular benefit in subjects who are at risk for cardiovascular disease or diabetes.”

Source: Nutrients