Glycaemic fall after a glucose load. A population-based study

Orthostatic hypotension does not increase cardiovascular risk in the elderly at a population level

BACKGROUND

The general belief that orthostatic hypotension (OH) predisposes to cardiovascular events is based on sparse and contradictory data, rarely derived from population studies.

METHODS

A total of 1,016 men and women aged ≥65 years was studied in a 12-year epidemiological population-based study. Cardiovascular events were detected in subjects with and without OH (blood pressure (BP) decrease ≥20mm Hg for systolic or ≥10mm Hg for diastolic), and Cox analysis was performed including OH as an independent variable.

RESULTS

In univariate analysis, coronary (20.2% vs. 13.1%, P = 0.05), cerebrovascular (13.1% vs. 8.4%, P = 0.05), and heart failure (HF) events (20.2% vs. 13.8%, P = 0.03) were apparently more incidental in subjects with OH than in those without OH. Nevertheless, after adjusting for age, gender, and systolic BP as confounders, OH did not act as a cardiovascular predictor (relative risk for cerebrovascular events 1.33, 95% confidence interval (CI), 0.78-2.2, for coronary events 1.25, CI 0.82-1.88, for HF 1.07, CI 0.71-1.62, for arrhythmias 0.82, CI 0.40-1.37, and for syncope 0.58, CI 0.13-2.71).

CONCLUSIONS

Although OH seems to be a predictor of coronary, cerebrovascular, and HF events, no predictive role was found in models that include biological confounders. Independent of the cause of OH, age and systolic BP, which are positively associated with OH, fully explain the greater incidence of cardiovascular events and the greater cardiovascular risk observed in subjects with OH.

Correlation between serum lipids and 1-hour postload plasma glucose levels in normoglycemic individuals

BACKGROUND

One-hour plasma glucose (1-h PG) level of ≥ 155 mg/dL during an oral glucose tolerance test (OGTT) predicts the development of type 2 diabetes mellitus among individuals with normal glucose tolerance (NGT). In addition, high triglyceride (TG) and low high-density lipoprotein-cholesterol (HDL-C) levels are risks factors for development of diabetes mellitus in the future.

OBJECTIVE

To examine the association between 1-h PG levels and serum lipid profiles in individuals with NGT.

METHODS

We enrolled 736 individuals with NGT who underwent a 75-g OGTT. They were divided into 2 groups, those with 1-h PG levels < 155 mg/dL (n = 543) and those with 1-h PG levels ≥ 155 mg/dL (n = 193). Multivariate linear regression analyses were performed to assess correlations between 1-h PG levels and lipid profiles.

RESULTS

The multiple linear regression analyses showed that 1-h PG levels negatively correlated with HDL-C in individuals with NGT who had 1-h PG levels ≥ 155 mg/dL as well as those with 1-h PG levels < 155 mg/dL (β = -0.137, P = .001 and β = -0.214, P = .003, respectively). In addition, 1-h PG levels positively correlated with log-transformed TG/HDL-C ratio in both groups (β = 0.098, P = .032 and β = 0.152, P = .035, respectively). Moreover, even after adjusting for confounding parameters, TG was higher and HDL-C was lower in individuals with NGT who had 1-h PG levels ≥ 155 mg/dL compared with those who had 1-h PG levels < 155 mg/dL.

CONCLUSION

HDL-C levels and TG/HDL-C ratios closely correlate with 1-h PG levels in individuals with NGT.

Cognitive Functions across the GNB3 C825T Polymorphism in an Elderly Italian Population

To verify whether the C825T polymorphism of the GNB3 influences the response to neuropsychological tests, mini-mental state examination, digit span (DS), immediate and delayed prose memory, memory with interference at 10 and 30 seconds (MI 10 and 30), trail making tests (TMTs) A and B, abstraction task, verbal fluency (VF) test, figure drawing and copying, overlapping figures test and clock test were performed in 220 elderly men and women free from clinical dementia and from neurological and psychiatric diseases randomly taken from the Italian general population and analysed across the C825T polymorphism. The performance of DS, immediate and delayed prose memory, VF, and TMTs was worse in subjects who were TT for the polymorphism in comparison to the C-carriers. The performance of all tests declined with age. In the case of DS, immediate and delayed prose memory, MI 10 and VF, this trend was maintained in the C-carriers but not in TT. In the case of prose memory, of memory with interference, and of VF, schooling reduced the detrimental interaction between age and genotype. The C825T polymorphism of GNB3 gene therefore influences memory and verbal fluency, being additive to the effects of age and partially mitigated by schooling.