Prospective associations of poor diet quality with long-term incidence of protein-energy malnutrition in community-dwelling older adults: the Health, Aging, and Body Composition (Health ABC) Study.

Background: Protein-energy malnutrition (PEM) is a major problem in older adults. Whether poor diet quality is an indicator for the long-term development of PEM is unknown.

Objective: The aim was to determine whether poor diet quality is associated with the incidence of PEM in community-dwelling older adults.

Design: We used data on 2234 US community-dwelling older adults aged 70-79 y of the Health, Aging, and Body Composition (Health ABC) Study. In 1998-1999, dietary intake over the preceding year was measured by using a Block food-frequency questionnaire. Indicators of diet quality include the Healthy Eating Index (HEI), energy intake, and protein intake. Outcomes were determined annually by using measured weight and height and included the following: 1) incident PEM [body mass index (in kg/m2) <20, involuntary weight loss of ≥5% in the preceding year at any follow-up examination, or both] and 2) incident persistent PEM (having PEM at 2 consecutive follow-up examinations). Associations of indicators of diet quality with 4-y and 3-y incidence of PEM and persistent PEM, respectively, were examined by multivariable Cox regression analyses.

Results: The quality of the diet, as assessed with the HEI, was rated as "poor" for 6.4% and as "needs improvement" for 73.0% of the participants. During follow-up, 24.9% of the participants developed PEM and 8.5% developed persistent PEM. A poor HEI score was not associated with incident PEM or persistent PEM. Lower baseline energy intake was associated with a lower incidence of PEM (HR per 100-kcal/d lower intake: 0.98; 95% CI: 0.97, 0.99) and persistent PEM (HR: 0.97; 95% CI: 0.95, 0.99), although lower baseline protein intake was observed to be associated with a higher incidence of persistent PEM (HR per 10-g/d lower intake: 1.15; 95% CI: 1.03, 1.29).

Conclusions: These findings do not indicate that a poor diet quality is a risk factor for the long-term development of PEM in community-dwelling older adults, although there is an indication that lower protein intake is associated with higher PEM risk.