Lower serum levels of IL-13 is associated with increased carotid intima-media thickness in old age subjects.

BACKGROUND: Cardiovascular diseases due to atherosclerosis represent the major cause of disability and mortality in old age subjects. The atherosclerotic process is linked to a low grade of systemic inflammation with the involvement of many cytokines and inflammatory proteins. Among them, evidence from animal studies suggests that IL-13 has a protective property. However, the role of IL-13 in the pathogenesis of atherosclerosis in humans is still unknown. AIMS: With this study, we aim to investigate a potential association between IL-13 and carotid intima-media thickness (IMT) in old age subjects. METHODS: This is a retrospective study conducted among 79 old age subjects (over 75 years old). All subjects underwent IMT assessment by high-resolution B-mode ultrasonography and IL-13 measurement in serum by ELISA. RESULTS: Subjects (41 M/38F) had a mean age of 81.0 ± 4.5 years and were mostly overweight. Stratifying the whole cohort by IMT thickness (IMT ≤ 0.9, n = 17; IMT ≥ 1 and ≤ 1.3, n = 50; IMT ≥ 1.4, n = 12) among the main variables explored, only BMI and triglycerides differed among groups, having subjects with higher IMT significantly higher BMI and lower triglycerides. Serum IL-13 levels significantly differed among groups having subjects with IMT ≥ 1.4 lower levels as compared to other groups (p < 0.0001). In all sample population, IMT values significantly correlate with IL-13 levels (r = - 0.454, p < 0.0001). Indeed, a linear regression analysis showed that independent of age, gender, body mass index, triglycerides, systolic blood pressure, statin use and smoking habit, lower IL-13 serum levels were associated with higher IMT values. CONCLUSIONS: IL-13, an anti-inflammatory cytokine, may have a protective role in the human atherosclerotic process. It could be used as an effective and promising novel therapeutic target development.

Cognitive Decline and Alzheimer's Disease in Old Age: A Sex-Specific Cytokinome Signature.

BACKGROUND: Elevated peripheral levels of different cytokines and chemokines in subjects with Alzheimer's disease (AD), as compared with healthy controls (HC), have emphasized the role of inflammation in such a disease. Considering the cross-talking between the central nervous system and the periphery, the inflammatory analytes may provide utility as biomarkers to identify AD at earlier stages. OBJECTIVE: Using an advanced statistical approach, we can discriminate the interactive network of cytokines/chemokines and propose a useful tool to follow the progression and evolution of AD, also in light of sex differences. METHODS: A cohort of 289 old-age subjects was screened for cytokine and chemokine profiling, measured in plasma, after a thorough clinical and neuropsychological evaluation. A custom algorithm based on Fisher linear discriminant analysis was applied to ascertain a classification signature able to discriminate HC from mild cognitive impairment (MCI) and AD. RESULTS: We observed that a joint expression of three proteins (a "signature" composed by IFN-α2, IL-1α, TNFα) can discriminate HC from AD with an accuracy of 65.24%. Using this signature on MCI samples, 84.93% of them were classified as "non-HC". Stratifying MCI samples by sex, we observed that 87.23% of women were classified as "non-HC", and only 57.69% of males. Indeed, in a scatter plot of IFN-α2 and IL-1α, the HC group was better separated from MCI and AD in women as compared with men. CONCLUSION: These findings suggest that AD is accompanied by a peripheral inflammatory response that can already be present in MCI subjects, thus providing a mean for detecting this at-risk status and allow an anticipated intervention.

Does the 15-item Geriatric Depression Scale function differently in old people with different levels of cognitive functioning?

BACKGROUND: The 15-item version of the Geriatric Depression Scale (GDS-15) is widely employed to screen depression among elderly but little is known about the scale functioning in cognitively impaired individuals when compared to normal ones. The aim of the current study is to investigate Differential Item Functioning (DIF) across groups of older people that differ in terms of cognitive functioning applying Item Response Theory (IRT)-based analyses. METHODS: Data from an Italian multi-centric clinical-based study on cognitive impairment and dementia in old people were employed (N = 1903; Age: M = 77.33, SD = 7.05, 62% women). All the participants underwent a comprehensive evaluation (including clinical examination, laboratory screening, neuroimaging, and cognitive and behavioral assessments) and they were assigned to three different groups on the basis of their cognitive functioning (normal, mild cognitive impairment, cognitive impairment) RESULTS: Two items showed uniform DIF but their differential functioning does not propagate to the GDS-15 total scores in such a way that a differential interpretation is needed LIMITATIONS: Whereas an advantage of the study is the large sample size, the relatively small size of the mild cognitive impairment group might reduce the stability of the present results CONCLUSIONS: Since a screening tool for elderly is intended to apply to everyone in the target population, the current findings support the clinical utility of the GDS-15 as screening tool for depression.

Biomarkers for Early Diagnosis of Alzheimer's Disease in the Oldest Old: Yes or No?

In recent years, many efforts have been spent to identify sensitive biomarkers able to improve the accuracy of Alzheimer's disease (AD) diagnosis. Two different workgroups (NIA-AA and IWG) included cerebrospinal fluid (CSF) and neuroimaging findings in their sets of criteria in order to improve diagnostic accuracy as well as early diagnosis. The number of subjects with cognitive impairment increases with aging but the oldest old (≥85 years of age), the fastest growing age group, is still the most unknown from a biological point of view. For this reason, the aim of our narrative mini-review is to evaluate the pertinence of the new criteria for AD diagnosis in the oldest old. Moreover, since different subgroups of oldest old have been described in scientific literature (escapers, delayers, survivors), we want to outline the clinical profile of the oldest old who could really benefit from the use of biomarkers for early diagnosis. Reviewing the literature on biomarkers included in the diagnostic criteria, we did not find a high degree of evidence for their use in the oldest old, although CSF biomarkers seem to be still the most useful for excluding AD diagnosis in the "fit" subgroup of oldest old subjects, due to the high negative predictive value maintained in this age group.