Improving diet-quality scores can reduce risk for CVD

Improving diet-quality scores reduce risk for CVD in both the short and long term, according to study results published in Circulation.

To investigate short-term and long-term impact of changes in diet-quality scores, researchers used two large, prospective cohorts — the Health Professionals Follow-up Study and the Nurses’ Health Study — to collect data on diet, lifestyle and medical conditions every 2 to 4 years from 1986 to 2010.

Mercedes Sotos-Prieto, PhD, of Harvard T.H. Chan School of Public Health, and colleagues examined changes during a 4-year period in three diet-quality scores: the Alternative Healthy Eating Index-2010 (AHEI-2010), the Alternate Mediterranean Diet (AMED) and the Dietary Approaches to Stop Hypertension (DASH).

Researchers followed 29,343 men in the Health Professionals Follow-up Study and 51,195 women in the Nurses’ Health Study from 1986 to 2010. Every 4 years, participants were sent a 131-item semiquantitative food-frequency questionnaire that queried how often and how much of certain foods were consumed.

The AHEI-2010 score focuses on the consumption of vegetables, fruit, whole grains, nuts and legumes. The AMED score emphasizes the components of the Mediterranean diet, but also looks at alcohol intake. The DASH diet aims to lower BP, and stresses low sodium and red and processed meat consumption.

During the study period, there were 11,793 cases of CVD, which included fatal and nonfatal MI and CABG surgery. Participants with the largest increase in diet-quality score had a reduction in CVD risk of 7% to 8%. The researchers calculated a pooled HR of 0.92 (95% CI, 0.87-0.99) for the AHEI-2010; 0.93 (95% CI, 0.85-1.02) for the AMED; and 0.93 (95% CI, 0.87-0.99) for the DASH diets (P for trend < .05 for all).

An increase in diet-quality score during the first 4 years of follow-up also contributed to lower CVD risk for the next 20 years (7% [95% CI, 1-12] for AEHI-2010 and 9% [95% CI, 3-14] for AMED). The same association was not observed with the DASH score, but a 16% decrease in DASH score was linked to an 8% (95% CI, 2-15) higher CVD risk over 20 years.

The researchers concluded that “the increase in CVD with a reduction in diet quality is more pronounced in longer-term than short-term follow-up. Our results provide further evidence that modest improvement in diet quality over time confers benefits for CVD prevention.” – by Tracey Romero

Disclosure: One researcher reports receiving research support from California Walnut Commission and Metagenics. The other researchers report no relevant financial disclosures.