Fatty-acid consumption linked with hypertension in older women

9 September 2010

MedWire News: Eating large quantities of saturated, monounsaturated, or trans-unsaturated (trans) fatty acids is associated with hypertension in middle-aged and older women, study findings indicate.

But only the link between trans fatty acids and hypertension remained statistically significant after adjusting for obesity-related factors, the researchers report in the journal Hypertension.

Lu Wang (Brigham and Women’s Hospital, Boston, Massachusetts, USA) and colleagues say their findings “suggest that an adverse diet profile, along with other unhealthy lifestyle [factors], may increase the risk of hypertension through promoting obesity”.

The findings come from 28,100 US women who took part in the Women’s Health Study and were aged at least 39 years, with neither cardiovascular disease nor cancer nor, for the current analysis, hypertension.

During a mean follow-up of 12.9 years, 13,633 women developed incident hypertension based on annual questionnaires that recorded self-reported physician diagnosis, medication use, and blood pressure.

Consumption of saturated fatty acids, monounsaturated fatty acids, and trans fatty acids were each positively associated with the risk for hypertension, after adjusting for demographic, lifestyle, and other dietary factors.

The multivariable relative risks for hypertension were 1.12, 1.11, and 1.15 among women in the highest quintile of intake of saturated fatty acids, monounsaturated fatty acids, and trans fatty acids, respectively, relative to those in the lowest quintile.

All associations decreased after further adjusting for body mass index, a history of diabetes, and hypercholesterolemia, and only that for trans fatty acids remained significant, with a relative risk for hypertension of 1.08 among women the highest versus lowest quintile.

Intake of polyunsaturated fatty acids, including omega-3 and -6, was not significantly associated with the risk for hypertension.

US guidelines recommend adults consume between 20% and 35% of calories as fat, with less than 10% of calories as saturated fatty acids and as little trans fatty acid as possible, but there is limited evidence on the relevance of this for preventing hypertension, Wang et al say.

They advise: “With total fat intake as a percentage of calories falling over recent decades, more specific recommendations on the optimal amount and type of fatty-acid intake for hypertension and cardiovascular disease prevention are needed.”

Hypertension 2010; Advance online publication