Dietary patterns and diet quality among diverse older adults: the University of Alabama at Birmingham Study of Aging

OBJECTIVES

To characterize dietary patterns among a diverse sample of older adults (≥ 65 years).

DESIGN

Cross-sectional.

SETTING

Five counties in west central Alabama.

PARTICIPANTS

Community-dwelling Medicare beneficiaries (N=416; 76.8 ± 5.2 years, 56% female, 39% African American) in the University of Alabama at Birmingham (UAB) Study of Aging.

MEASUREMENTS

Dietary data collected via three, unannounced 24-hour dietary recalls was used to identify dietary patterns. Foods were aggregated into 13 groups. Finite mixture modeling (FMM) was used to classify individuals into three dietary patterns. Differences across dietary patterns for nutrient intakes, sociodemographic, and anthropometric measurements were examined using chi-square and general linear models.

RESULTS

Three dietary patterns were derived. A "more healthful" dietary pattern, with relatively higher intakes of fruit, vegetables, whole grains, eggs, nuts, legumes and dairy, was associated with lower energy density, higher quality diets as determined by healthy eating index (HEI)-2005 scores and higher intakes of fiber, folate, vitamins C and B6, calcium, iron, magnesium, and zinc. The "western-like" pattern was defined by an intake of starchy vegetables, refined grains, meats, fried poultry and fish, oils and fats and was associated with lower HEI-2005 scores. The "low produce, high sweets" pattern was characterized by high saturated fat, and low dietary fiber and vitamin C intakes. The strongest predictors of better diet quality were female gender and non-Hispanic white race.

CONCLUSION

The dietary patterns identified may provide a useful basis on which to base dietary interventions targeted at older adults. Examination of nutrient intakes regardless of the dietary pattern suggests that older adults are not meeting nutrient recommendations and should continue to be encouraged to choose high quality diets.

Dietary patterns and relationship to obesity-related health outcomes and mortality in adults 75 years of age or greater

BACKGROUND

The prevalence of obesity-related adverse health outcomes is increasing among older adults. Because it is thought that nutrition plays an important role in successful aging, there has been considerable interest in the association between dietary patterns of older adults and obesity-related health outcomes.

OBJECTIVE

This study examined the association between dietary patterns and mortality and prevalence of obesity-related health outcomes, namely cardiovascular disease (CVD), type 2 diabetes mellitus, hypertension, and metabolic syndrome (MetSyn), over a 5-year follow-up period in adults aged 75 years or greater.

DESIGN

A longitudinal observational study with cross-sectional dietary assessment.

SETTING

Rural Central Pennsylvania.

PARTICIPANTS

Community-dwelling older adults (N = 449; 76.5 years old; 57% female).

MEASUREMENTS

Multiple, unannounced, 24-hour dietary recalls were used to collect dietary intake. Cluster analysis was used to derive dietary patterns. Prevalence of CVD, diabetes mellitus, hypertension, and MetSyn was extracted from outpatient electronic medical records. Logistic regression was used to examine the associations between dietary patterns and health outcomes and mortality.

RESULTS

'Sweets and Dairy', 'Health-Conscious' and 'Western' dietary patterns were identified. Compared to the 'Health-Conscious' pattern, those in the 'Sweets and Dairy' pattern had increased odds of hypertension over the follow-up period; adjusted odds ratio (95% CI) was 2.18 (1.11-4.30). No significant associations were found for CVD, diabetes mellitus, MetSyn or mortality with dietary patterns.

CONCLUSIONS

These findings support the potential value of healthy dietary patterns in the management of hypertension in older adults. We did not observe any other strong associations between dietary patterns and health outcomes or mortality in persons ≥ 75 years of age; thus failing to support the use of overly restrictive diet prescriptions for older persons, especially where food intake may be inadequate.

Is the optimal level of protein intake for older adults greater than the recommended dietary allowance?

BACKGROUND

Protein is a macronutrient essential for growth, muscle function, immunity and overall tissue homeostasis. Suboptimal protein intake can significantly impact physical function and overall health in older adults.

METHODS

This article reviews the literature on the recommendations for protein intake in older adults in light of the new evidence linking protein intake with sarcopenia and physical function. Challenges and opportunities for optimal protein nutrition in older persons are discussed.

RESULTS

Recent metabolic and epidemiological studies suggest that the current recommendations of protein intake may not be adequate for maintenance of physical function and optimal health in older adults. Methodological limitations and novel concepts in protein nutrition are also discussed.

CONCLUSION

We conclude that new research and novel research methodologies are necessary to establish the protein needs and optimal patterns of protein intake for older persons.

Relative validity of the Geisinger Rural Aging Study food frequency questionnaire

OBJECTIVE

To determine the relative validity of a population specific food frequency questionnaire (FFQ) and evaluate the effectiveness of the instrument for assessing nutritional risk in older adults.

DESIGN

A cross-over design with participants completing two different dietary assessment instruments in random order.

SETTING

The Geisinger Rural Aging Study (GRAS), a longitudinal study of over 20,000 adults living in the central, northern and eastern counties of Pennsylvania.

PARTICIPANTS

A subset of GRAS consisting of 245 older adults (60% women) ranging in age from 70 to 95 years.

MEASUREMENTS

Energy and nutrient intakes were assessed from two instruments: a population specific food frequency questionnaire (FFQ) and four 24-hour dietary recalls conducted over a two week period.

RESULTS

Pearson correlation coefficients between the FFQ and dietary recalls for most nutrients were 0.5 or higher which suggests that the FFQ provided relatively valid estimates of macro and micronutrient intakes examined. Bland-Altman plots were generated to examine the agreement between instruments. Data are shown for energy, folate and zinc with close agreement at lower intakes indicative of risk for folate and zinc. Sensitivity results also showed that the FFQ was able to correctly classify individuals adequately at risk for most nutrients examined.

CONCLUSION

This population specific FFQ appears to be a valid instrument for use in in evaluating risk for many nutrients that are of particular concern in older adults residing throughout many predominately rural counties in Pennsylvania.

International consensus guidelines for nutrition therapy in pancreatitis

Guidelines for nutrition support in pancreatitis have been inconsistently adapted to clinical practice. The International Consensus Guideline Committee (ICGC) established a pancreatitis task force to review published guidelines for pancreatitis in nutrition support. A PubMed search using the terms pancreatitis, acute pancreatitis, chronic pancreatitis, nutrition support, parenteral nutrition, enteral nutrition, and guidelines was conducted for the period from January 1999 to May 2011. Eleven guidelines were identified for review. The ICGC used the following process to develop unified guideline statements: summarize the strength of evidence (grading) of the guidelines; establish level of evidence for ICGC statements as high, intermediate, and low; assign published guideline levels of evidence; and define an ICGC grading system. International Pancreatitis Guideline Grades were established as follows: platinum-high level of evidence and consistent agreement among the guidelines; gold-acceptable level of evidence and no conflicting statements in guidelines; and silver-single existing guideline statement with no conflict in other guidelines. Eighteen ICGC statements were derived from the 11 published pancreatitis guidelines. Uniform agreement from widely disparate groups (United States, Europe, Japan, and China) resulted in 4 platinum-level guideline statements for nutrition in pancreatitis: nutrition support therapy (NST) is generally not needed for mild to moderate disease, NST is needed for severe disease, enteral nutrition (EN) is preferred over parenteral nutrition (PN), and use PN when EN is contraindicated or not feasible. This methodology provides a template for future ICGC nutrition guideline development.

Interrelationships between tissue iron status and erythropoiesis during postweaning development following neonatal iron deficiency in rats

Dietary iron is particularly critical during periods of rapid growth such as in neonatal development. Human and rodent studies have indicated that iron deficiency or excess during this critical stage of development can have significant long- and short-term consequences. Since the requirement for iron changes during development, the availability of adequate iron is critical for the differentiation and maturation of individual organs participating in iron homeostasis. We have examined in rats the effects of dietary iron supplement following neonatal iron deficiency on tissue iron status in relation to erythropoietic ability during 16 wk of postweaning development. This physiological model indicates that postweaning iron-adequate diet following neonatal iron deficiency adversely affects erythroid differentiation in the bone marrow and promotes splenic erythropoiesis leading to splenomegaly and erythrocytosis. This altered physiology of iron homeostasis during postweaning development is also reflected in the inability to maintain liver and spleen iron concentrations and the altered expression of iron regulatory proteins in the liver. These studies provide critical insights into the consequences of neonatal iron deficiency and the dietary iron-induced cellular signals affecting iron homeostasis during early development.

A postweaning iron-adequate diet following neonatal iron deficiency affects iron homeostasis and growth in young rats

Iron deficiency is among the most prevalent of nutrient-related diseases worldwide, but the long-term consequences of maternal and neonatal iron deficiency on offspring are not well characterized. We investigated the effects of a postweaning iron-adequate diet following neonatal iron deficiency on the expression of genes involved in iron acquisition and homeostasis. Pregnant rats were fed an iron-adequate diet (0.08 g iron/kg diet) until gestational d 15, at which time they were divided into 2 groups: 1) a control group fed an iron-adequate diet, and 2) an iron-deficient group fed an iron-deficient diet (0.005 g iron/kg diet) through postnatal d (P) 23 (weaning). After weaning, pups from both dietary treatment groups were fed an iron-adequate diet until adulthood (P75). Rat pups that were iron deficient during the neonatal period (IDIA) had reduced weight gain and hemoglobin concentrations and decreased levels of serum, liver, and spleen iron on P75 compared with rats that were iron sufficient throughout early life (IA). IDIA rats developed erythrocytosis during postweaning development. Further, hepatic expression of hepcidin in IDIA rats was 1.4-fold greater than in IA rats, which paralleled an upregulation of IL-1 expression in the serum. Our data suggest that an iron-adequate diet following neonatal iron deficiency induced an inflammatory milieu that affected iron homeostasis and early growth and development.

Challenges and new opportunities for clinical nutrition interventions in the aged

Nutritional status plays a critical role in the prevention and management of many chronic health conditions that are common in the elderly and are likely to become more prevalent as the population ages. This paper highlights several aspects of nutrition that require additional basic science and clinical application research to improve the health and well-being of older adults. Topics addressed are selected demographic and health indices, the uncertain benefits of energy restriction in aged humans compared with other species, the impact of food insecurity on health, the relationship between dietary protein and sarcopenia, the prevention and management of obesity while maintaining muscle mass and functional status, and controversy regarding high intakes of folic acid. Research needs regarding the safety, efficacy, and application of clinical interventions related to these topics also are discussed.

Iron chelation down-regulates dopamine transporter expression by decreasing mRNA stability and increasing endocytosis in N2a cells

Cell surface expression of the dopamine transporter (DAT) is determined by the relative rates of its internalization and recycling. Changes in the cellular labile iron pool (LIP) affect many cellular mechanisms including those that regulate DAT trafficking. In this study, we analyzed DAT expression and posttranslational modifications in response to changes in cellular iron in transfected neuroblastoma cells (N2a). Iron chelation by desferrioxamine (DFO) altered DAT protein levels by decreasing the stability of DAT mRNA. Increased phosphorylation and ubiquitination of this transporter protein following DFO treatment were also observed. Cellular iron depletion elevated protein levels of the early endosomal marker Rab5. Moreover, confocal microscopy studies showed increased localization of DAT into the endosomal compartment in DFO-treated cells compared to control. Together, these findings suggest that cellular iron depletion regulates DAT expression through reducing mRNA stability as well as an increasing in endocytosis.

Food intake patterns and body mass index in older adults: a review of the epidemiological evidence

The relationship between food intake patterns and obesity remains unclear. The objective of the present review was to evaluate the current body of literature on food intake patterns of older adults and their associations with weight status, including obesity and waist circumference. Eleven observational studies were identified and reviewed. Diets characterized by more favorable dietary scores or indices were generally inversely related to body mass index. Results from data-driven approaches were inconsistent. Findings from this literature review suggest that there is no clear relationship between food intake patterns and body mass index or waist circumference in older adults. Limitations, including heterogeneity of food intake patterns and study populations, hinder the ability to make clear comparisons. Continued efforts to elucidate the relationship between food intake patterns and weight status indicators in older adults, including longitudinal analyses and use of novel statistical approaches for food intake pattern identification, are warranted.

Adult starvation and disease-related malnutrition: a proposal for etiology-based diagnosis in the clinical practice setting from the International Consensus Guideline Committee

BACKGROUND & AIMS

Multiple definitions for malnutrition syndromes are found in the literature resulting in confusion. Recent evidence suggests that varying degrees of acute or chronic inflammation are key contributing factors in the pathophysiology of malnutrition that is associated with disease or injury.

METHODS

An International Guideline Committee was constituted to develop a consensus approach to defining malnutrition syndromes for adults in the clinical setting. Consensus was achieved through a series of meetings held at the A.S.P.E.N. and ESPEN Congresses.

RESULTS

It was agreed that an etiology-based approach that incorporates a current understanding of inflammatory response would be most appropriate. The Committee proposes the following nomenclature for nutrition diagnosis in adults in the clinical practice setting. "Starvation-related malnutrition", when there is chronic starvation without inflammation, "chronic disease-related malnutrition", when inflammation is chronic and of mild to moderate degree, and "acute disease or injury-related malnutrition", when inflammation is acute and of severe degree.

CONCLUSIONS

This commentary is intended to present a simple etiology-based construct for the diagnosis of adult malnutrition in the clinical setting. Development of associated laboratory, functional, food intake, and body weight criteria and their application to routine clinical practice will require validation.

Lipid emulsions in parenteral nutrition of intensive care patients: current thinking and future directions

Background

Energy deficit is a common and serious problem in intensive care units and is associated with increased rates of complications, length of stay, and mortality. Parenteral nutrition (PN), either alone or in combination with enteral nutrition, can improve nutrient delivery to critically ill patients. Lipids provide a key source of calories within PN formulations, preventing or correcting energy deficits and improving outcomes.

Discussion

In this article, we review the role of parenteral lipid emulsions (LEs) in the management of critically ill patients and highlight important biologic activities associated with lipids. Soybean-oil-based LEs with high contents of polyunsaturated fatty acids (PUFA) were the first widely used formulations in the intensive care setting. However, they may be associated with increased rates of infection and lipid peroxidation, which can exacerbate oxidative stress. More recently developed parenteral LEs employ partial substitution of soybean oil with oils providing medium-chain triglycerides, ω-9 monounsaturated fatty acids or ω-3 PUFA. Many of these LEs have demonstrated reduced effects on oxidative stress, immune responses, and inflammation. However, the effects of these LEs on clinical outcomes have not been extensively evaluated.

Conclusions

Ongoing research using adequately designed and well-controlled studies that characterize the biologic properties of LEs should assist clinicians in selecting LEs within the critical care setting. Prescription of PN containing LEs should be based on available clinical data, while considering the individual patient’s physiologic profile and therapeutic requirements.

Obesity in older adults: relationship to functional limitation

PURPOSE OF REVIEW

The present review is intended to provide a critical overview of recent investigations of obesity among older persons with emphasis upon associated functional limitations, potential for intervention, and a future research agenda.

RECENT FINDINGS

Obesity is growing in prevalence among older persons. The association between obesity and functional decline is well documented. Recent findings suggest possible contributions of obesity-associated inflammatory milieu, sarcopenia, and impairment of muscle function/strength to adverse functional outcomes. A growing body of literature supports consideration of moderate weight reduction to secure improved metabolic and functional parameters for obese older persons.

SUMMARY

Obesity is associated with an unfortunate burden of chronic disease, functional limitation, and poor life quality. In view of the growing numbers of afflicted older individuals, there must be research priority to discern how obesity impacts function so that appropriate prevention and treatment strategies may be adopted.

Malnutrition in North America: where have we been? Where are we going?

Malnutrition was first highlighted as a prevalent concern in hospital care more than 30 years ago. In response the nutrition support field grew precipitously but changes in the healthcare environment have culminated in a period of accountability and consolidation in nutrition support practice over the past decade. Evolving regulatory environment and reimbursement policies have had a profound impact upon nutrition support and these trends are likely to continue. Both undernutrition and overnutrition (obesity) remain prevalent concerns in North America. In particular the growing prevalence of overweight/obesity will have far-reaching implications for nutrition support practitioners and will require the development, testing, and validation of new standards of assessment, intervention, and monitoring. Adoption of common language and definitions by practitioners will facilitate standardized interventions, outcome measures, and high quality research. The future remains bright with tailored nutrition interventions poised to become a part of the individual medical treatment plan for specific patient conditions and genotypes. Future research priorities should include studies of nutritional modulation of inflammatory conditions with specific nutrients and functional foods and the testing of individualized nutritional interventions tailored to gene polymorphisms.