Nutritional status predicts primary subclasses of T cells and the lymphocyte proliferation response in healthy older women

Interaction of central obesity and sarcopenia on nutritional status in the community-dwelling older people

OBJECTIVES

To investigate the interrelationships between central obesity, sarcopenia and nutritional status in the elderly.

METHODS

We enrolled 501 elderly (women: 47.5 %) with complete datasets. Biochemical and anthropometric data were measured after an overnight fast. Basic characteristics, psychosocial and behavioral factors, nutritional status, and history of chronic disease came from structured questionnaires. Central obesity was defined as waist circumference ≥ 90 cm for men, ≥ 80 cm for women. Sarcopenia was defined by the Asian consensus. Nutritional status was assessed using Mini Nutritional Assessment scores: abnormal nutritional status ≤ 23.5. Multiple logistic regression analysis was done to determine the independent factors of an abnormal nutritional status.

RESULTS

Ninety (18.0 %) participants had an abnormal nutritional status, 300 (59.9 %) had central obesity, 52 (10.4 %) sarcopenia and 3 (0.6 %) sarcopenic obesity. Central obesity (OR = 0.455, 95 % CI: 0.244-0.847) and total lymphocyte count (OR = 0.526, 95 % CI: 0.315-0.880) were negatively and sarcopenia (OR = 3.170, 95 % CI: 1.485-6.767), current smoking (OR = 4.071, 95 % CI: 1.357-12.211), and total number of chronic diseases (OR = 1.484, 95 % CI: 1.234-1.785) were positively associated with abnormal nutritional status. An analysis of the combine effects of central obesity and sarcopenia on nutritional status showed that significantly fewer participants with central obesity but not sarcopenia had abnormal nutrition than participants with sarcopenia with or without central obesity (12.8 % vs 38.5 or 65.4 %, p < 0.001).

CONCLUSIONS

Central obesity and sarcopenia were interactively associated with the nutritional status of older people living in a rural community.

A holistic approach to healthy ageing: how can people live longer, healthier lives?

BACKGROUND

Although lifespan is increasing, there is no evidence to suggest that older people are experiencing better health in their later years than previous generations. Nutrition, at all stages of life, plays an important role in determining health and wellbeing.

METHODS

A roundtable meeting of UK experts on nutrition and ageing considered key aspects of the diet-ageing relationship and developed a consensus position on the main priorities for research and public health actions that are required to help people live healthier lives as they age.

RESULTS

The group consensus highlighted the requirement for a life course approach, recognising the multifactorial nature of the impact of ageing. Environmental and lifestyle influences at any life stage are modified by genetic factors and early development. The response to the environment at each stage of life can determine the impact of lifestyle later on. There are no key factors that act in isolation to determine patterns of ageing and it is a combination of environmental and social factors that drives healthy or unhealthy ageing. Too little is known about how contemporary dietary patterns and sedentary lifestyles will impact upon healthy ageing in future generations and this is a priority for future research.

CONCLUSIONS

There is good evidence to support change to lifestyle (i.e. diet, nutrition and physical) activity in relation to maintaining or improving body composition, cognitive health and emotional intelligence, immune function and vascular health. Lifestyle change at any stage of life may extend healthy lifespan, although the impact of early changes appears to be greatest.

Association of micronutrient status with subclinical health complaints in lactovegetarian adults

Background

Micronutrient malnutrition has many adverse effects on human health, not all of which may be clinically evident.

Objective

To explore linkages between subclinical health complaints and micronutrient status in lactovegetarian Indian adults.

Design

Health was assessed in 502 lactovegetarian adults (275 men, 227 women, aged 30.6±9 years) using a structured questionnaire for existing complaints with severity of symptoms on a four-point scale and morbidity over the preceding month. Subjects were categorized as having no complaints (NC), or complaints of mild (MI) or moderate (MD) degree, using cluster analysis. Diet was recorded by a semi-quantitative food frequency questionnaire and nutrient intakes were computed using standard databases. Levels of haemoglobin, vitamin C, retinol, ceruloplasmin, riboflavin (EGRAC), folic acid, vitamin B₁₂ and erythrocyte membrane zinc (RBCMZn) in blood were estimated.

Results

Health complaints of a mild and moderate degree were observed in 30.5% and 24.7% of the subjects, respectively. Average dietary intakes of β-carotene, riboflavin, iron and zinc were observed to be only about half of the recommended dietary intakes. There was a decreasing trend in micronutrient intakes from NC to MD. Intakes of iron, zinc, niacin and thiamin of men from the MI group tended to be lower than in the NC group (p<0.1). Men from the MD group had significantly lower intakes of calcium, zinc and riboflavin than those from the NC group (p<0.05). The intakes of these nutrients in women from NC, MI and MD were not significantly different. Multinomial logistic regression of health status revealed that plasma vitamin C and RBCMZn were negatively associated with MD and RBCMZn with MI.

Conclusions

The study indicates a need to increase micronutrient intakes of vegetarian populations, especially regarding vitamin C and zinc for maintenance of health.

Inflammation and Nutritional Science for Programs/Policies and Interpretation of Research Evidence (INSPIRE)

An increasing recognition has emerged of the complexities of the global health agenda—specifically, the collision of infections and noncommunicable diseases and the dual burden of over- and undernutrition. Of particular practical concern are both 1) the need for a better understanding of the bidirectional relations between nutritional status and the development and function of the immune and inflammatory response and 2) the specific impact of the inflammatory response on the selection, use, and interpretation of nutrient biomarkers. The goal of the Inflammation and Nutritional Science for Programs/Policies and Interpretation of Research Evidence (INSPIRE) is to provide guidance for those users represented by the global food and nutrition enterprise. These include researchers (bench and clinical), clinicians providing care/treatment, those developing and evaluating programs/interventions at scale, and those responsible for generating evidence-based policy. The INSPIRE process included convening 5 thematic working groups (WGs) charged with developing summary reports around the following issues: 1) basic overview of the interactions between nutrition, immune function, and the inflammatory response; 2) examination of the evidence regarding the impact of nutrition on immune function and inflammation; 3) evaluation of the impact of inflammation and clinical conditions (acute and chronic) on nutrition; 4) examination of existing and potential new approaches to account for the impact of inflammation on biomarker interpretation and use; and 5) the presentation of new approaches to the study of these relations. Each WG was tasked with synthesizing a summary of the evidence for each of these topics and delineating the remaining gaps in our knowledge. This review consists of a summary of the INSPIRE workshop and the WG deliberations.

Immunological and nutritional factors in elderly people in low-level care and their association with mortality

Background

This study examines associations between markers of nutritional status and lymphocyte subsets and seeks to determine if lymphocyte profile is predictive of survival in elderly Australians residing in aged care facilities. Aged yet still ambulatory subjects (n = 88, 73% female) living in low-level care and requiring minimal assistance were studied for 143 weeks. At baseline when participants were aged (mean ± SD) 86.0 ± 5.9 years, dietary intake was determined by 3-day weighed food record, body composition was assessed by dual energy X-ray absorptiometry (DXA) and a venous blood sample was taken.

Results

At baseline assessment, study participants were consuming nutrient-poor diets and most had symptoms of chronic disease. Although overweight, 40% exhibited sarcopenia. Markers of nutritional status did not relate closely to immune cell numbers (absolute or relative), which on average were within the normal range. Men had lower numbers of CD3⁺CD4⁺ cells (CD4⁺ T cells), a higher proportion of CD3⁻ CD16^± CD56^± (natural killer (NK) cells) and a higher ratio of NK: CD4⁺ T cells than women (all P < 0.05). The main age-related changes evident were decreased T cells, particularly low CD4⁺ T cell counts, and increased numbers of CD19⁺ (B-cell) and NK cells. During the 143 week duration of follow-up, about one quarter of the study participants died, with death more likely in men than women (P < 0.01). Poor survival was predicted by the presence of decreased numbers of CD4⁺ T cells (hazard ratio (HR) 0.919, P < 0.01) and expanded numbers of NK cells (HR 1.085, P < 0.05) in the blood, and therefore the presence of a high NK: CD4⁺ T cell ratio (HR 30.521, P < 0.01).

Conclusions

The NK: CD4⁺ T cell ratio may potentially have clinical utility for predicting longevity in elderly populations. Further studies are needed in other elderly populations to confirm this finding.

Supplementation of essential amino acids may reduce the occurrence of infections in rehabilitation patients with brain injury

BACKGROUND

To investigate whether supplementation with oral essential amino acids (EAAs) may reduce the occurrence of nosocomial infection among patients with brain injury (BI: stroke, trauma, anoxic coma).

METHODS

Patients (n = 125; 77 men, 48 women; mean age 63 ± 15 years) with stroke (68.8%), subarachnoid hemorrhage (17.6%), traumatic BI (7.2%), and anoxic BI (6.4%) 88 ± 15 days after the index event. Patients were randomly assigned to 2 months of oral EAAs (n = 63; 8 g/d) or placebo (n = 62).

RESULTS

Over the first month of rehabilitation, there were 60 infections in the whole population of 125 patients (48%); however, the rate was 23.2% lower in the EAA group (23 episodes/63 patients; 36.5%) than in the placebo group (37 episodes/62 patients; 59.7%) (P < .01). The types of infection were similarly distributed between the 2 groups. Serum levels of prealbumin <20 mg/dL and C-reactive protein (CRP) >0.3 mg/dL were the best predictors of future infection (prealbumin: odds ratio [OR] = 4.17, confidence interval [CI] 1.84-9.45, P < .001; CRP: OR = 3.8, CI 1.71-8.44, P < .001).

CONCLUSION

Supplementary EAAs may reduce the occurrence of nosocomial infections in rehabilitation patients with BI. Prealbumin and CRP are the best predictors of future infections.

The inflammatory status of the elderly: the intestinal contribution

A common finding in the elderly population is a chronic subclinical inflammatory status that coexists with immune dysfunction. These interconnected processes are of sufficient magnitude to impact health and survival time. In this review we discuss the different signals that may stimulate the inflammatory process in the aging population as well as the molecular and cellular components that can participate in the initiation, the modulation or termination of the said process. A special interest has been devoted to the intestine as a source of signals that can amplify local and systemic inflammation. Sentinel cells in the splanchnic area are normally exposed to more than one stimulus at a given time. In the intestine of the elderly, endogenous molecules produced by the cellular aging process and stress as well as exogenous evolutionarily conserved molecules from bacteria, are integrated into a network of receptors and molecular signalling pathways that result in chronic inflammatory activation. It is thus possible that nutritional interventions which modify the intestinal ecology can diminish the pro-inflammatory effects of the microbiota and thereby reinforce the mucosal barrier or modulate the cellular activation pathways.

Immunological outcomes of exercise in older adults

Aging is associated with a dysregulation of the immune system known as immunosenescence. Immunosenescence involves cellular and molecular alterations that impact both innate and adaptive immunity, leading to increased incidences of infectious disease morbidity and mortality as well as heightened rates of other immune disorders such as autoimmunity, cancer, and inflammatory conditions. While current data suggests physical activity may be an effective and logistically easy strategy for counteracting immunosenescence, it is currently underutilized in clinical settings. Long-term, moderate physical activity interventions in geriatric populations appear to be associated with several benefits including reduction in infectious disease risk, increased rates of vaccine efficacy, and improvements in both physical and psychosocial aspects of daily living. Exercise may also represent a viable therapy in patients for whom pharmacological treatment is unavailable, ineffective, or inappropriate. The effects of exercise impact multiple aspects of immune response including T cell phenotype and proliferation, antibody response to vaccination, and cytokine production. However, an underlying mechanism by which exercise affects numerous cell types and responses remains to be identified. Given this evidence, an increase in the use of physical activity programs by the healthcare community may result in improved health of geriatric populations.

Association of Body Mass Index of HIV-1-Infected Pregnant Women and Infant Weight, Body Mass Index, Length, and Head Circumference: The NISDI Perinatal Study

This study assessed the relationship between the body mass index (BMI) of HIV-1-infected women and their infants' perinatal outcomes. The study population consisted of women enrolled in the NICHD International Site Development Initiative (NISDI) Perinatal Study with data allowing calculation of the BMI adjusted for length of gestation (adjBMI), who delivered singleton infants. Outcome variables included infant growth parameters at birth (weight, BMI, length and head circumference) and gestational age. Of 697 women from Argentina, the Bahamas, Brazil and Mexico who were included in the analysis, the adjBMI was classified as underweight for 109 (15.6%), normal for 418 (60.0%), overweight for 88 (12.6%) and obese for 82 (11.8%). Median infant birth weight, BMI, birth length and head circumference differed significantly according to maternal adjBMI (P</=0.0002). Underweight mothers gave birth to infants with lower weight, lower BMI, shorter length and smaller head circumference, while infants born to normal, overweight and obese mothers were of similar size.

Characterization of immune system alterations following preoperative autologous blood donation for elective hip replacement surgery

Preoperative autologous blood donation (PABD) has been shown to decrease natural killer (NK) cell function in cancer patients, raising concerns about an increased cancer recurrence risk owing to PABD. It is unclear whether PABD leads to other immunomodulatory effects that might affect more short-term risks like postoperative infectious complications in surgical patients. Lymphocyte subsets (CD4+ T cells, CD8+ T cells, B cells, NK cells) were determined in 86 consecutive patients donating 2 units of autologous whole blood prior to elective hip replacement surgery. In addition, cytokine secretion patterns of monocytes [tumour necrosis factor (TNF)] and lymphocytes [interferon-gamma, interleukin (IL)-2, IL-4, IL-10] upon stimulation were determined in a random subgroup of 58 patients. Analyses were performed immediately before the first donation and on the day prior to operation. Granulocytes increased during PABD by 4.6% (P < 0.01). Lymphocytes decreased by 8.8% (P < 0.01), accompanied by a relative rise in CD4+ T cells by 10.7% (P < 0.01) and in B cells by 10.3% (P < 0.01), and a fall of NK cells by 20.8% (P < 0.01). Stimulated TNF secretion of monocytes was suppressed (-12.3%, P < 0.01). The effect on the reactivity of lymphocytes and the T helper 1 (Th1)/Th2 balance were variable. The observed changes of innate and cellular immunity might influence the risk of perioperative infectious complications.

Immunity and ageing in man

Immunosenescence resulting in decreased ability to control infectious disease contributes to morbidity and mortality not only in the very elderly, but in all likelihood already from middle age. Studying immunity in humans is therefore essential for developing treatments to restore dysregulated immune responses and assure healthy longevity. The past year has seen many significant advances in our knowledge of age-associated alterations to immunity in elderly people, only some of which can be briefly reviewed here.