Determinants of fat-soluble vitamin status in patients aged 65 years and over

Oxidative stress, aging, antioxidant supplementation and their impact on human health: An overview

Aging is characterized by a progressive loss of tissue and organ function due to genetic and environmental factors, nutrition, and lifestyle. Oxidative stress is one the most important mechanisms of cellular senescence and increased frailty, resulting in several age-linked, noncommunicable diseases. Contributing events include genomic instability, telomere shortening, epigenetic mechanisms, reduced proteome homeostasis, altered stem-cell function, defective intercellular communication, progressive deregulation of nutrient sensing, mitochondrial dysfunction, and metabolic unbalance. These complex events and their interplay can be modulated by dietary habits and the ageing process, acting as potential measures of primary and secondary prevention. Promising nutritional approaches include the Mediterranean diet, the intake of dietary antioxidants, and the restriction of caloric intake. A comprehensive understanding of the ageing processes should promote new biomarkers of risk or diagnosis, but also beneficial treatments oriented to increase lifespan.

Creatinine, total cysteine and uric acid are associated with serum retinol in patients with cardiovascular disease

Purpose

We hypothesized that biomarkers and dietary factors related to cardiovascular disease risk were associated with serum retinol and evaluated these potential associations in patients with suspected coronary artery disease (CAD).

Methods

We used cross-sectional data from 4116 patients hospitalised for suspected CAD. Dietary data were obtained from a subgroup of 1962 patients using a food frequency questionnaire. Potential biomarkers and dietary factors were explored using linear regression modelling adjusted for age and sex. Regression coefficients and corresponding confidence intervals (CI) are given as  % change in serum retinol per unit change in the predictors. Analyses were performed in the total population and in strata of serum retinol tertiles.

Results

In age- and sex-adjusted models, serum creatinine (standardized β: 0.38, 95% CI [0.35, 0.42]), plasma total cysteine (0.26, [0.23, 0.29]), serum uric acid (0.30, [0.26, 0.33]) and plasma neopterin (0.22, [0.18, 0.25]) were positively associated, whereas plasma serine (− 0.15, [− 0.18, − 0.12]) and serum C-reactive protein (− 0.15, [− 0.18, − 0.12]) were inversely associated with serum retinol. When we included the significant biomarkers in a multivariate model, the model explained 33% of the variability (R² = 0.33) in serum retinol. The results were similar in the lower and upper tertiles of serum retinol. Weak or no associations were observed for dietary factors.

Conclusions

In patients with suspected CAD, concentrations of creatinine, cysteine and uric acid were positively associated with serum retinol. Future studies should assess whether retinol concentrations are influenced by metabolic alterations in patients at risk of cardiovascular disease.

Association between 25-OH-vitamin D and C-reactive protein as a marker of inflammation and cardiovascular risk in clinical practice

Background

C-reactive protein is an acute phase response marker and, in an epidemiological context, a predictor of cardiovascular risk. 25-Hydroxy-vitamin D is the best indicator for vitamin D status, but it can be altered by the presence of acute phase response. Our aim was to evaluate the association between serum concentrations of 25-hydroxy-vitamin D and C-reactive protein to assist the interpretation of vitamin D status in a clinical context.

Methods

We evaluated retrospectively 5076 patients ( n = 4087 women) assessed for 25-hydroxy-vitamin D and C-reactive protein simultaneously. Subjects were classified according to the origin as hospitalized patients ( n = 410) and outpatients ( n = 4666). Outpatients included patients from specialized ( n = 3943) and primary ( n = 723) care. Serum 25-hydroxy-vitamin D was determined by using liquid chromatography and serum C-reactive protein by using immunoturbidimetry.

Results

Concentrations of 25-hydroxy-vitamin D and C-reactive protein were significantly different between hospitalized subjects and outpatients but not for specialized and primary care settings. Serum concentrations of 25-hydroxy-vitamin D decreased as C-reactive protein increased. Hospitalized patients with C-reactive protein concentrations >30 mg/L showed a significant reduction of 25-hydroxy-vitamin D. In outpatients with C-reactive protein within the reference range (≤10 mg/L), C-reactive protein concentrations were not significantly different for serum 25-hydroxy-vitamin D concentrations >37.5 nmol/L.

Conclusions

Our data question the reliability and usefulness of assessing 25-hydroxy-vitamin D status as a biomarker of nutritional status in patients displaying acute phase response, especially at concentrations of C-reactive protein >30 mg/L. In addition, the present study shows that in subjects displaying C-reactive protein values within the reference range, serum concentrations of 25-hydroxy-vitamin D >37.5 nmol/L were not associated with lower concentrations of cardiovascular risk (as assessed by C-reactive protein concentrations).

Vitamin D status and associated factors among Portuguese older adults: results from the Nutrition UP 65 cross-sectional study

OBJECTIVES

To evaluate vitamin D status and its associated factors in Portuguese older adults from the Nutrition UP 65 study.

DESIGN

Cross-sectional observational study.

PARTICIPANTS AND METHODS

Nationwide cluster sample of 1500 Portuguese subjects ≥65 years old. Participants were classified, according to US Institute of Medicine cut-offs, as presenting normal 25-hydroxyvitamin D (25(OH)D) levels (≥50.0 nmol/L), at risk of inadequacy (30.0-49.9 nmol/L) or at risk of deficiency (<30 nmol/L). The association between individuals' characteristics and 25(OH)D levels was analysed through multinomial logistic regression analysis.

RESULTS

Median 25(OH)D serum value was 36.1 (interquartile range (IQR): 35.5) nmol/L. According to the used cut-offs, 39.6% of participants were at risk of 25(OH)D deficiency and 29.4% were at risk of 25(OH)D inadequacy. In the adjusted model, having higher skin pigmentation and waist circumference >88 cm for women and >102 cm for men were associated with higher odds of 25(OH)D deficiency. Otherwise, living in Lisbon Metropolitan Area and in Madeira, 1-12 years of schooling, being married or in a common-law marriage, monthly income ≥€1000, alcohol consumption, medication or supplements with vitamin D supplement use, and blood samples collected in spring or summer were associated with lower odds of being at risk of 25(OH)D deficiency. In this model, season of blood sample collection, medication or supplements use, and waist circumference were the factors more strongly associated with 25(OH)D levels.

CONCLUSIONS

Despite using the conservative Institute of Medicine cut-offs, over two-thirds of these study participants presented inadequate 25(OH)D levels, warranting the implementation of corrective measures. Potentially modifiable factors were strongly associated with 25(OH)D levels in this study. These findings may be particularly relevant to the development of public health policies in southern European countries.

Happily (n)ever after: Aging in the context of oxidative stress, proteostasis loss and cellular senescence

Aging is a complex phenomenon and its impact is becoming more relevant due to the rising life expectancy and because aging itself is the basis for the development of age-related diseases such as cancer, neurodegenerative diseases and type 2 diabetes. Recent years of scientific research have brought up different theories that attempt to explain the aging process. So far, there is no single theory that fully explains all facets of aging. The damage accumulation theory is one of the most accepted theories due to the large body of evidence found over the years. Damage accumulation is thought to be driven, among others, by oxidative stress. This condition results in an excess attack of oxidants on biomolecules, which lead to damage accumulation over time and contribute to the functional involution of cells, tissues and organisms. If oxidative stress persists, cellular senescence is a likely outcome and an important hallmark of aging. Therefore, it becomes crucial to understand how senescent cells function and how they contribute to the aging process. This review will cover cellular senescence features related to the protein pool such as morphological and molecular hallmarks, how oxidative stress promotes protein modifications, how senescent cells cope with them by proteostasis mechanisms, including antioxidant enzymes and proteolytic systems. We will also highlight the nutritional status of senescent cells and aged organisms (including human clinical studies) by exploring trace elements and micronutrients and on their importance to develop strategies that might increase both, life and health span and postpone aging onset.

Nutritional Strategies Facing an Older Demographic: The Nutrition UP 65 Study Protocol

Background

The population of Portugal is aging. The lack of data on older adults’ nutritional status and the lack of nutrition knowledge amongst health professionals, caregivers, and older adults themselves, remains a challenge.

Objective

The Nutrition UP 65 study aims to reduce nutritional inequalities in the older Portuguese adult population and improve knowledge regarding older Portuguese adults’ nutritional status, specifically relating to undernutrition, obesity, sarcopenia, frailty, hydration, sodium, and vitamin D statuses.

Methods

A representative sample of older Portuguese adults was selected. Sociodemographic, lifestyle, anthropometric, functional, and clinical data were collected. Sodium excretion, hydration, and vitamin D statuses were assessed.

Results

Data collection (n=1500) took place between December, 2015 and June, 2016. Results will be disseminated in national and international scientific journals, and via Portuguese media.

Conclusions

Nutrition UP 65 results will provide evidence for the design and implementation of effective preventive public health strategies regarding the elderly. These insights may represent relevant health gains and costs savings.

Criteria of adequacy for vitamin D testing and prevalence of deficiency in clinical practice

Background:

Vitamin D deficiency is an important concern in clinical settings although there is no consensus on who should undergo 25-OH-vitamin D testing. We studied the prevalence of vitamin D deficiency before and after introducing adequacy (clinical and biochemical) criteria for testing.

Methods:

A total of 32,363 tests for 25-OH-vitamin D were retrospectively evaluated. Requests were unrestricted until December 2010 and justification criteria were applied from January 2011. During 6 years, 25,656 samples were analyzed (UHPLC) of which 12,315 were considered the first visit. The prevalence of deficiency was assessed for all the samples and according to the year, sex, season, age, origin of the requests, inclusion of adequacy criteria and consecutive visits.

Results:

A significant proportion of the requests (25%) were unjustified and less than half of the clinically or biochemically-justified tests displayed serum concentrations indicative of deficiency. Application of adequacy criteria resulted in a non-significant increase in the prevalence of deficiency, both at the first visit (36.5 vs. 41.7, p=0.17) and for all the samples analyzed (32.0 vs. 35.5, p=0.14). The percentage of deficiency decreased in consecutive visits although 2/3 and 41% of the patients remained deficient on the second and third visit, respectively. Moreover, at least 1/5 of sufficient patients at the first test became deficient in subsequent evaluations.

Conclusions:

A significant proportion of the requests was unjustified by clinical or biochemical criteria. Our data also indicate that clinical and biochemical criteria may be necessary (to be present) to justify vitamin D testing but not sufficient (predictive) to indicate the presence of vitamin D deficiency.

Focus on Pivotal Role of Dietary Intake (Diet and Supplement) and Blood Levels of Tocopherols and Tocotrienols in Obtaining Successful Aging

Numerous specific age-related morbidities have been correlated with low intake and serum levels of tocopherols and tocotrienols. We performed a review in order to evaluate the extant evidence regarding: (1) the association between intake and serum levels of tocopherols and tocotrienols and age-related pathologies (osteoporosis, sarcopenia and cognitive impairment); and (2) the optimum diet therapy or supplementation with tocopherols and tocotrienols for the treatment of these abnormalities. This review included 51 eligible studies. The recent literature underlines that, given the detrimental effect of low intake and serum levels of tocopherols and tocotrienols on bone, muscle mass, and cognitive function, a change in the lifestyle must be the cornerstone in the prevention of these specific age-related pathologies related to vitamin E-deficient status. The optimum diet therapy in the elderly for avoiding vitamin E deficiency and its negative correlates, such as high inflammation and oxidation, must aim at achieving specific nutritional goals. These goals must be reached through: accession of the elderly subjects to specific personalized dietary programs aimed at achieving and/or maintaining body weight (avoid malnutrition); increase their intake of food rich in vitamin E, such as derivatives of oily seeds (in particular wheat germ oil), olive oil, hazelnuts, walnuts, almonds, and cereals rich in vitamin E (such as specific rice cultivar rich in tocotrienols) or take vitamin E supplements. In this case, vitamin E can be correctly used in a personalized way either for the outcome from the pathology or to achieve healthy aging and longevity without any adverse effects.

Serum 25-Hydroxyvitamin D Level Could Predict the Risk for Peritoneal Dialysis-Associated Peritonitis

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BACKGROUND

As an immune system regulator, vitamin D is commonly deficient among patients on peritoneal dialysis (PD), which may contribute to their impaired immune function and increased risk for PD-related peritonitis. In this study, we aimed to investigate whether vitamin D deficiency could predict the risk of peritonitis in a prospective cohort of patients on PD. ♦

METHODS

We collected 346 prevalent and incident PD patients from 2 hospitals. Baseline demographic data and clinical characteristics were recorded. Serum 25-hydroxyvitamin D (25[OH]D) was measured at baseline and prior to peritonitis. The mean doses of oral active vitamin D used during the study period were also recorded. The outcome was the occurrence of peritonitis. ♦

RESULTS

The mean age of patients and duration of PD were 58.95 ± 13.67 years and 28.45 (15.04 - 53.37) months, respectively. Baseline 25(OH)D level was 16.15 (12.13 - 21.16) nmol/L, which was closely associated with diabetic status, longer PD duration, malnutrition, and inflammation. Baseline serum 25(OH)D predicted the occurrence of peritonitis independently of active vitamin D supplementation with a hazard ratio (HR) of 0.94 (95% confidence interval [CI] 0.90 - 0.98) after adjusting for recognized confounders (age, gender, dialysis duration, diabetes, albumin, residual renal function, and history of peritonitis). Compared to the low tertile, middle and high 25(OH)D level tertiles were associated with a decreased risk for peritonitis with HRs of 0.54 (95% CI 0.31 - 0.94) and 0.39 (95% CI 0.20 - 0.75), respectively. ♦

CONCLUSIONS

Vitamin D deficiency evaluated by serum 25(OH)D rather than active vitamin D supplementation is closely associated with a higher risk of peritonitis.