High plasma insulin and lipids profile in older individuals: the Italian longitudinal study on aging

Reversible Cognitive Frailty, Dementia, and All-Cause Mortality. The Italian Longitudinal Study on Aging

OBJECTIVES

Cognitive frailty, a condition describing the simultaneous presence of physical frailty and mild cognitive impairment, has been recently defined by an international consensus group. We estimated the predictive role of a "reversible" cognitive frailty model on incident dementia, its subtypes, and all-cause mortality in nondemented older individuals. We verified if vascular risk factors or depressive symptoms could modify this predictive role.

DESIGN

Longitudinal population-based study with 3.5- and 7-year of median follow-up.

SETTING

Eight Italian municipalities included in the Italian Longitudinal Study on Aging.

PARTICIPANTS

In 2150 older individuals from the Italian Longitudinal Study on Aging, we operationalized reversible cognitive frailty with the presence of physical frailty and pre-mild cognitive impairment subjective cognitive decline, diagnosed with a self-report measure based on item 14 of the Geriatric Depression Scale.

MEASUREMENTS

Incidence of dementia, its subtypes, and all-cause mortality.

RESULTS

Over a 3.5-year follow-up, participants with reversible cognitive frailty showed an increased risk of overall dementia [hazard ratio (HR) 2.30, 95% confidence interval (CI) 1.02-5.18], particularly vascular dementia (VaD), and all-cause mortality (HR 1.74, 95% CI 1.07-2.83). Over a 7-year follow-up, participants with reversible cognitive frailty showed an increased risk of overall dementia (HR 2.12, 95% CI 1.12-4.03), particularly VaD, and all-cause mortality (HR 1.39, 95% CI 1.03-2.00). Vascular risk factors and depressive symptoms did not have any effect modifier on the relationship between reversible cognitive frailty and incident dementia and all-cause mortality.

CONCLUSIONS

A model of reversible cognitive frailty was a short- and long-term predictor of all-cause mortality and overall dementia, particularly VaD. The absence of vascular risk factors and depressive symptoms did not modify the predictive role of reversible cognitive frailty on these outcomes.

Association of subclinical inflammation with polyneuropathy in the older population: KORA F4 study

OBJECTIVE

Inflammatory processes have been implicated in the pathogenesis of diabetic distal sensorimotor polyneuropathy (DSPN), but their possible relationship has not been assessed at the population level.

RESEARCH DESIGN AND METHODS

We determined serum concentrations of mediators of subclinical inflammation among 1,047 participants 61-82 years of age from the population-based Cooperative Health Research in the Region of Augsburg (KORA) F4 study (Germany). Logistic and linear regression models were fitted to assess associations between immune mediators (log-transformed) and the presence of clinical DSPN (dichotomous variable) or Michigan Neuropathy Screening Instrument (MNSI) examination score (continuous variable), respectively.

RESULTS

Serum concentrations of the anti-inflammatory interleukin (IL)-1 receptor antagonist (IL-1RA) were positively associated with the presence of DSPN and higher MNSI scores in age-adjusted and sex-adjusted analyses, whereas IL-6, IL-18, and soluble intercellular adhesion molecule-1 were positively associated with only MNSI scores. No associations were observed for adiponectin, C-reactive protein, or tumor necrosis factor-α. Associations for IL-1RA and IL-6 with the MNSI score remained statistically significant after additional adjustment for waist circumference, height, hypertension, cholesterol, smoking, alcohol intake, physical activity, history of myocardial infarction or stroke, presence of neurological conditions, and use of nonsteroidal anti-inflammatory drugs.

CONCLUSIONS

We conclude that DSPN is linked to proinflammatory and anti-inflammatory, possibly compensatory, processes in the older general population. Future studies should clarify the temporal sequence and causality of these associations.

Genistein ameliorates hyperglycemia in a mouse model of nongenetic type 2 diabetes

While peripheral insulin resistance is common during obesity and aging in mice and people, the progression to type 2 diabetes (T2D) is largely due to loss of β-cell mass and function through apoptosis. We recently reported that genistein, a soy derived isoflavone, can improve glycemic control and β-cell function in insulin-deficient diabetic mice. However, whether it can prevent β-cell loss and diabetes in T2D mice is unknown. Our current study aimed to investigate the effect of dietary supplemented genistein in a nongenetic T2D mouse model. Nongenetic, middle-aged obese diabetic mice were generated by high fat diet and a low dose of streptozotocin injection. The effect of dietary supplementation of genistein on glycemic control and β-cell mass and function was determined. Dietary intake of genistein (250 mg·kg(-1) diet) improved hyperglycemia, glucose tolerance, and blood insulin level in obese diabetic mice, whereas it did not affect body weight gain, food intake, fat deposit, plasma lipid profile, and peripheral insulin sensitivity. Genistein increased the number of insulin-positive β-cell in islets, promoted islet β-cell survival, and preserved islet mass. In conclusion, dietary intake of genistein could prevent T2D via a direct protective action on β-cells without alteration of periphery insulin sensitivity.

Frailty syndrome and all-cause mortality in demented patients: the Italian Longitudinal Study on Aging

Cognition has already been considered as a component of frailty, and it has been demonstrated that it is associated with adverse health outcomes. We estimated the prevalence of frailty syndrome in an Italian older population and its predictive role on all-cause mortality and disability in nondemented subjects and in demented patients. We evaluated 2,581 individuals recruited from the Italian Longitudinal Study on Aging, a population-based sample of 5,632 subjects, aged 65-84 years old. Participants received identical baseline evaluation at the 1st survey (1992-1993) and were followed at 2nd (1995-1996) and 3rd survey (2000-2001). A phenotype of frailty according to partially modified measurement of Cardiovascular Health Study criteria was operationalized. The overall prevalence of frailty syndrome in this population-based study was 7.6% (95% confidence interval (CI) 6.55-8.57). Frail individuals noncomorbid or nondisable were 9.1% and 39.3%, respectively, confirming an overlap but not concordance in the co-occurrence among these conditions. Frailty was associated with a significantly increased risk of all-cause mortality over a 3-year follow-up (hazard ratio (HR) 1.98, 95% confidence interval (CI) 1.52-2.60) and over a 7-year follow-up (HR 1.74, 95% CI 1.44-2.16), but with significant increased risk of disability only over a 3-year follow-up (HR 1.32, 95% CI 1.06-1.86 over a 3-year follow-up and HR 1.16, 95% CI 0.88-1.56 over a 7-year follow-up). Frail demented patients were at higher risk of all-cause mortality over 3- (HR 3.33, 95% CI 1.28-8.29) and 7-year follow-up periods (HR 1.89, 95% CI 1.10-3.44), but not of disability. Frailty syndrome was a short-term predictor of disability in nondemented older subjects and short- and long-term predictor of all-cause mortality in nondemented and demented patients.

Metabolic syndrome, mild cognitive impairment, and progression to dementia. The Italian Longitudinal Study on Aging

We investigated the relationship of metabolic syndrome (MetS) and its individual components with incidence of mild cognitive impairment (MCI) and its progression to dementia in a large longitudinal Italian population-based sample with a 3.5-year follow-up. A total of 2097 participants from a sample of 5632 65-84-year-old subjects from the Italian Longitudinal Study on Aging were evaluated. MetS was defined according to the Third Adults Treatment Panel of the National Cholesterol Education Program criteria. MCI, dementia, Alzheimer's disease (AD), and vascular dementia (VaD) were classified using current published criteria. Among MCI patients those with MetS (N=49) had a higher risk of progression to dementia (HR, 4.40; 95% CI, 1.30-14.82) compared with those without MetS (N=72). After a multivariate adjustment, the risk in MCI patients with MetS approximately doubled (multivariate adjusted HR, 7.80, 95% CI 1.29-47.20) compared with those MCI without MetS. Finally, among non-cognitively impaired individuals there were no significant differences in risks of developing MCI in those who were affected by MetS (N=608) in comparison with those without MetS (N=837), as well as excluding those individuals with undernutrition or low inflammatory status with or without undernutrition. In our population, among MCI patients the presence of MetS independently predicted an increased risk of progression to dementia over 3.5 years of follow-up.

Issues surrounding age: vascular disease in the elderly

One-fifth of all humans who have survived beyond the age of 65 are alive today, and in the industrialized world the elderly segment of the population is expanding most rapidly. In biological terms, these survivors are healthier than the elderly of previous generations. However 'there are no diseases peculiar to old age and very few from which it is exempt' (Alfred Worcester, 1855-1951), and so society will inevitably accumulate a significant share of degenerative diseases within the ranks of its senior citizens. In the last two decades, the prevalence of stroke, diabetes mellitus, arthritis and heart disease has increased significantly as a tangible index of ageing in the population, and these diseases have been accompanied by degenerating cognitive function and physical disability, both of which are adding increasing stress to community healthcare and social services. Policy-makers need to understand and monitor these trends in order to make informed and cogent decisions about the management of this growing problem. This review highlights some of the key health issues facing the elderly in regard to coronary artery disease, insulin resistance, redox status, and statin therapy, in the hope that enlightened debate will inform decision making on resource allocation for this important and growing segment of society.