Sex Differences in Frailty Incidence in Greek Community-Dwelling Older People: The HELIAD Study.

BACKGROUND: Previous frailty studies found higher prevalence of frailty in female than in male participants. This was mainly attributed to the fact that compared to men, women show increased longevity. Recent studies have reported that the observed difference between sexes applies irrespectively of the age of older people. OBJECTIVES: To provide data on sex differences in incident frailty by applying both phenotypic and multi-domain frailty measures in the same population of Greek community-dwelling older people. DESIGN: Longitudinal study. SETTING: Data were drawn from the Hellenic longitudinal Investigation of Aging and Diet (HELIAD), a population-based, multidisciplinary study designed to estimate the prevalence and incidence of dementia in the Greek population. PARTICIPANTS: 1104 participants aged 65 year and above were included in this longitudinal study. This incidence cohort was re-evaluated after a mean follow-up period of 3.04±0.90 years. MEASUREMENTS: Frailty was operationalized using 5 different definitions in the same population: the Fried Frailty Phenotype (FFP) definition, the FRAIL Scale, the Frailty Index (FI), the Tilburg Frailty Indicator (TFI) and the Groningen Frailty Index (GFI). Frailty incidence was calculated a) for the whole sample, b) separately for men and women and c) after both age and sex stratification. RESULTS: Age and sex stratification revealed that irrespective of age and frailty measurement, women showed higher incidence rates of frailty than men. Specifically, frailty seems to be a condition concerning women >65 years old, but when it comes to men, it is more frequent in those aged more than 75 years old. Finally, in relation to overall frailty incidence and comparing our results to previous studies, we detected a lower frailty incidence in the Greek population. CONCLUSIONS: Differences between the two sexes indicate that when exploring the factors that are related to frailty, studies should provide data disaggregated for men and women.

Plasma GSH levels and Alzheimer's disease. A prospective approach.: Results from the HELIAD study.

BACKGROUND: Potential links between oxidative stress and the pathophysiology of Alzheimer's disease (AD) have been reported in the existing literature. Biological markers of oxidative stress, such as the reduced form of glutathione (GSH), may have a potential role as predictive biomarkers for AD development. The aim of the present study was to explore the longitudinal associations between plasma GSH and the risk of developing AD or cognitive decline, in a sample of community-dwelling, non-demented older adults. METHODS: Participants from the Hellenic Longitudinal Investigation of Aging and Diet (HELIAD) were included in the present prospective study. The sample used in the analyses consisted of 391 non-demented individuals over the age of 64 (mean age = 73.85 years; SD = 5.06), with available baseline GSH measurements and longitudinal follow-up. Plasma GSH was treated both as a continuous variable and as tertiles in our analyses. Cox proportional hazards models were used to evaluate the hazard ratio (HR) for AD incidence as a function of baseline plasma GSH. Generalized estimating equations (GEE) models were deployed to explore the associations between baseline plasma GSH and the rate of change of performance scores on individual cognitive domains over time. Models were adjusted for age, years of education and sex. Supplementary exploratory models were also adjusted for mild cognitive impairment (MCI) at baseline, risk for malnutrition, physical activity and adherence to the Mediterranean dietary pattern. RESULTS: A total of 24 incident AD cases occurred during a mean (SD) of 2.99 (0.92) years of follow-up. Individuals in the highest GSH tertile group (highest baseline plasma GSH values) had a 70.1% lower risk for development of AD, compared to those in the lowest one [HR = 0.299 (0.093-0.959); p = 0.042], and also demonstrated a slower rate of decline of their executive functioning over time (5.2% of a standard deviation less decline in the executive composite score for each additional year of follow-up; p = 0.028). The test for trend was also significant suggesting a potential dose-response relationship. CONCLUSION: In the present study, higher baseline plasma GSH levels were associated with a decreased risk of developing AD and with a better preservation of executive functioning longitudinally.

Prevalence and Risk Factors of Frailty in a Community-Dwelling Population: The HELIAD Study.

Objective: To estimate the prevalence of frailty using five different instruments in a cohort of older adults and explore the association between frailty and various risk factors. Method: 1,867 participants aged 65 years and above were included in the current retrospective cross-sectional study. Frailty was operationalized according to the Fried definition, the FRAIL Scale, the Frailty Index (FI), the Tilburg Frailty Indicator (TFI), and the Groningen Frailty Index (GFI). We explored the role of various frailty risk factors using logistic regression analyses. Results: The prevalence of frailty varied depending on the definition used (Fried definition = 4.1%, FRAIL Scale = 1.5%, FI = 19.7%, TFI = 24.5%, and GFI = 30.2%). The only risk factors consistently associated with frailty irrespectively of definition were education and age. Conclusion: The frailty prevalence reported in our study is similar or lower to that reported in other population studies. Qualitative differences between frailty definitions were observed.

Acute effect of smoking and smoking abstinence on energy intake and appetite-related hormones blood concentrations.

The effect of smoking on energy balance and the underlying mechanisms are not fully understood. The aim of the present study is to examine the acute effect of smoking and its abstinence on energy intake, subjective feelings of appetite and related hormones. Fourteen healthy smokers participated in a randomized, crossover study consisting of two trials: the Cigarette trial (participants smoked two cigarettes of their brand within 15min) and the Sham trial (they were asked to hold the cigarette as smoking, but without lighting it). After 45min the participants were offered an ad libitum variety of snacks, and their intake was recorded. Blood samples were taken at fasting, before the ad libitum meal and 1h after and were analyzed for obestatin, ghrelin, glucagon-like peptide-1, cholecystokinin and insulin levels. Subjective feelings of hunger, satiety and desired to eat, as well as smoking craving were evaluated by visual analog scales. Mean energy intake at the ad libitum meal was 825±310kcal in the Sham trial and 673±245kcal in the Cigarette trial (p=0.010). No significant intervention effects were observed for the reported appetite feelings or the appetite-related hormones levels. In conclusion, smoking was found to have an acute effect on dietary intake; this was not explained by changes in the hormonal levels that were evaluated. More research is needed to confirm these results in more prolonged periods of abstinence and explore other pathways through which smoking and its abstinence affect energy balance.

History of induced abortions and frailty in older Greek women: results from the HELIAD study.

PURPOSE: Women are almost twice as likely as men to develop frailty and early-traumatic experiences related to reproduction may have a role to play. The purpose of this study was to investigate the association between a history of induced abortions and risk of frailty. METHODS: 1062 women aged ≥ 65 years from the HELIAD study were included in the present cross-sectional study. Frailty was assessed by frailty index and Fried definitions. The history of abortion and of other reproductive experiences (age onset of menstruation, age of menopause, number of offspring, and number of miscarriages) was obtained by all participants. Logistic and linear regression analyses were performed to examine whether the number of abortions was related to frailty. RESULTS: When frailty was defined with frailty index, women with 1 or 2 abortions had 1.7 higher risk of frailty compared to women with no history of abortions, while those with more than 3 abortions had more than a twofold higher risk of frailty. Two supplementary analyses excluding women with surgical operations' history and women with dementia revealed similar results. When frailty was defined with Fried definition, the analysis was marginally significant when abortion was inserted as a categorical variable. Women with more than 3 abortions showed 2.4 higher risk of frailty compared to women with no history of abortion. CONCLUSION: The number of induced abortions was associated with moderate higher odds of frailty, when frailty was defined according to frailty index. A similar trend was revealed in the model with Fried definition after trichotomization of abortions.

Sleep quality is associated with weight loss maintenance status: the MedWeight study.

Sleep duration and quality have been associated with many health outcomes, including weight management. We aimed to investigate the effect of self-reported sleep duration and quality on weight loss maintenance in participants of the MedWeight study, a registry of individuals that lost at least 10% of body weight in the past and either maintained the loss (maintainers: weight maintenance of at least 10% of initial weight loss) or regained it (regainers: weight ≥95% of their maximum body weight). Study participants included 528 volunteers (61% women). Sleep quantity referred to the reported duration of nocturnal sleep, as well as the frequency of mid-day naps during the last month. Sleep quality was assessed through the Athens Insomnia Scale (AIS). Reported sleep quantity was associated with weight maintenance status, but the association became non-significant when the AIS score entered the model. In specific, AIS was inversely associated with the likelihood of being a maintainer (OR=0.89 per AIS unit, 95% CI: 0.81 - 0.98), even after adjusting for potential confounders. Sex-specific analysis revealed that the association between the AIS score and maintenance status was evident in men but not in women. Future studies are needed to confirm these results in other population groups and reveal underlying mechanisms.

Intracellular diglycerides in relation to glycaemic control in the myocardium: A pilot study in humans.

AIM: Intramyocellular diglycerides have been implicated in the development of insulin resistance in skeletal muscle. In the myocardium, excess lipid storage may also contribute to the appearance of diabetic cardiomyopathy, while diglycerides may have certain cardio-protective functions. However, little is known on intracellular diglyceride accumulation in the human heart. We aimed to determine diglyceride accumulation in the human myocardium in relation to diabetes status. METHODS: Six diabetic and six non-diabetic aged human subjects undergoing by-pass surgery participated in the study. Subjects were matched for age and body mass index. Intracellular diglyceride levels were measured in heart biopsy samples. Additional samples were taken from pectoralis major muscle that served as control. Whole body glycaemic control was assessed as the percent glycated haemoglobin. RESULTS: Intracellular diglycerides were significantly higher in the myocardium compared to pectoralis major (P<0.05). Although not statistically significant, diabetic subjects tended to accumulate smaller amounts of diglycerides compared to non-diabetic subjects in the myocardium. A linear negative correlation was observed between myocardial diglycerides and glycaemic control (r=0.632, P<0.05). CONCLUSIONS: Our data suggest that poor glycaemic control and diabetes may be associated with a defective accumulation of myocardial diglycerides, possibly blunting intracellular processes and contributing to the development of cardiomyopathy.

Moderate weight loss depletes intramyocellular triglycerides but has no effect on diglycerides in type II diabetes.

Intramyocellular diglycerides have been implicated in the development of insulin resistance. We aimed to evaluate the effect of weight loss, a well-known means for the improvement of insulin resistance, on intramyocellular diglycerides and triglycerides in type II diabetes. Participants were five obese women with type II diabetes (body mass index 37.5+/-1.9 kg/m(2)), who participated in a weight loss program. The aim of the program was a reduction in body weight by 10%. Muscle biopsies were obtained before and after weight loss. The intervention induced a marked reduction in intramyocellular triglycerides by 77.7+/-13.1%, whereas no significant differences were observed for diglycerides before and after weight loss. Our results indicate that weight loss due to negative energy balance depletes intramyocellular lipid storage without affecting intermediate molecules of lipid metabolism, such as intramyocellular diglycerides.

Changes in free radical generation and antioxidant capacity during ultramarathon foot race.

BACKGROUND: Exhaustive exercise has been implicated in the generation of reactive oxygen species, resulting in oxidative stress. We studied the effect of a long-distance, endurance exercise on oxidative stress parameters in athletes who participated in the ultramarathon race Spartathlon (246 km). MATERIALS AND METHODS: This study included 18 runners (16 men and 2 women) aged 42.8 +/- 1.4 years. Blood samples were obtained 24 h before (prerace), at the end (postrace) and 48 h after the end of the race (48 h postrace). We measured oxidative stress indices, including red cell glutathione, malonyldialdehyde and 8-iso-prostaglandin F(2a), as well as the total antioxidant capacity. RESULTS: 8-Iso-prostaglandin F(2a) level increased significantly at the end of the race, compared to prerace levels (up to 914.7 +/- 61.4 pg mL(-1) from 197.6 +/- 8.4 pg mL(-1)), and remained 2.5-fold increased over the baseline 48 h after the race (532.0 +/- 54.2 pg mL(-1), P < 0.000). The total antioxidant capacity of the athletes increased from a baseline of 289.6 +/- 9.0 micromol L(-1) to 358.7 +/- 11.0 micromol L(-1) immediately after the race and remained elevated 48 h later (350.6 +/- 7.6 micromol L(-1)) (P < 0.001). CONCLUSIONS: Prolonged exercise induces a marked response of oxidative stress biomarkers, which in part is compensated by serum ability to scavenge free radicals. Whether these changes have long-term negative effects in the organism needs further investigation.

Planar amplitudes in maximally supersymmetric Yang-Mills theory.

The collinear factorization properties of two-loop scattering amplitudes in dimensionally regulated N=4 super-Yang-Mills theory suggest that, in the planar ('t Hooft) limit, higher-loop contributions can be expressed entirely in terms of one-loop amplitudes. We demonstrate this relation explicitly for the two-loop four-point amplitude and, based on the collinear limits, conjecture an analogous relation for n-point amplitudes. The simplicity of the relation is consistent with intuition based on the anti-de Sitter/conformal field theory correspondence that the form of the large-N(c) L-loop amplitudes should be simple enough to allow a resummation to all orders.

Effect of isoniazid, a haem inhibitor, on globin chain synthesis in reticulocytes from non-thalassaemic and beta thalassaemic subjects.

The effect of isonicotinic acid hydrazide (INH), a potent haem inhibitor, on globin chain synthesis was studied in reticulocytes from the following groups of patients: four non-thalassaemic patients (group i); five beta thalassaemia heterozygotes (group ii); three Hb S/beta thalassaemia heterozygotes (group iii); and two additional patients--one with homozygous beta thalassaemia and the other with thalassaemia intermedia (group iv). This was done to determine whether haem inhibitors depress alpha globin chain synthesis. The progressive increase of INH concentration (10-40 mmol l-1) in reticulocytes from a beta thalassaemia heterozygote resulted in a remarkable decrease of the alpha and beta chain synthesis, ranging from 80% to 97% and from 74% to 96% of control values, respectively, and in a gradual drop of alpha:beta ratio from 1.87 to 1.38. Furthermore, in the samples incubated with 40 mmol l-1 INH, a pronounced inhibition of globin chain synthesis 77 (19%) for alpha chain and 67 (27%) for beta or beta S chain) and a substantial drop of the alpha:beta or beta S ratio in samples with INH (median 1.16) compared with that in samples without INH (median 1.70) were observed. The inhibitory effect of INH was significantly or completely corrected by adding exogenous haem. It is suggested that haem inhibition and the resulting preferential diminution of alpha chain synthesis could provide a new approach to the treatment of homozygous beta thalassaemia with an excess of detrimental free alpha chain in erythroid cells.

24-h blood glucose pattern in type I and type II diabetics after oral treatment with pentoxifylline as assessed by artificial endocrine pancreas.

Based on the known action of xanthine derivatives on the insulin secretion, the effect of pentoxifylline on carbohydrate homeostasis of type I (IDDM) and type II (NIDDM) diabetics was investigated. Pentoxifylline is known to exert a favorable influence on hemorheological disturbances in such patients. Twenty-four hour blood glucose pattern and insulin requirements were evaluated in type I and type II diabetics by the use of the artificial pancreas before and after a 14-day treatment with pentoxifylline 400 mg p.o. (Trental 400) t.i.d. During the stabilization period before treatment with pentoxifylline, NIDDM patients required 10.1 +/- 3.8 U of insulin and the IDDM 35 +/- 13.7 U. After 2 weeks on pentoxifylline, NIDDM required only 6.3 +/- 2.8 U (p less than 0.05) and IDDM 28.5 +/- 9.7 U (n.s.). Average blood glucose during the 24h decreased by 15.8 +/- 3.5% in NIDDM and by 10.3 +/- 2.5% in IDDM. Moreover, a significant smoothing of glucose fluctuations during the 24h was noted in both groups. It is concluded that pentoxifylline administered concurrently to any antidiabetic type of treatment leads to better blood glucose control as well as to prevention or delay of vascular complications.

Estimation of glycated fetal hemoglobin in normal cord blood by isoelectric focusing. Correlation with maternal glycated hemoglobin and birth weight.

Glycated fractions of hemoglobin F and A (F1, A1c) were measured simultaneously in cord and maternal blood, respectively, in 109 normal women at delivery using an isoelectric focusing, method in polyacrylamide gel plates. Cord blood hemoglobin F1 values (mean +/- SD) were 5.92 +/- 1.09% and maternal blood hemoglobin A1c values were 6.51 +/- 0.92%. The difference was statistically highly significant (p less than 0.001) and their values were also significantly correlated (p less than 0.001). Moreover, both values were also well correlated with those of maternal blood glucose (p less than 0.01), actual birth weight (p less than 0.01) and birth weight ratio (p less than 0.01). It is concluded that hemoglobin F1 can be successfully separated and measured by isoelectric focusing. However HbF1 estimation seems to have no obvious advantages against the maternal HbA1c measurement as an index of fetal exposure to glucose during the last weeks of pregnancy.

Plasma alpha-lipoprotein pattern in acute viral hepatitis.

In the present study, the plasma levels of lipoproteins, triglycerides, and cholesterol were followed serially in a group of 57 patients with acute viral hepatitis. Mean plasma triglyceride levels were found elevated at the onset of the disease and gradually returned to normal, while mean plasma cholesterol values, low initially, gradually increased, alpha-lipoprotein was absent at the early stage of hepatitis in 41 out of 46 patients with mild or moderate course and reappeared gradually during the course of the disease. In 11 cases of viral hepatitis with impending or overt coma, alpha-lipoprotein was absent for the whole duration of the acute stage and never reappeared in those who eventually died, while it eventually returned to normal in those who survived. The reappearance of alpha-lipoprotein in acute viral hepatitis appears to be a sensitive index of improvement and a significant prognostic sign.