Cardiometabolic comorbidities and epidemiological features among rural Chinese elderly people

BACKGROUND

China had already entered the aging society and taken up the largest number of elderly among the world.

AIMS

We intend to estimate cardiometabolic comorbidities situation among elderly coming from rural China.

METHODS

We conducted a survey during 2012 to 2013 which enrolled 1744 elderly from rural Northeast China. Data regarding the demographic and lifestyle characteristics and the blood biochemical indexes of these participants were collected by well-trained personnel.

RESULTS

Data in this study shows that the prevalence of hypertension, diabetes, dyslipidemia, obesity, stroke and hyperuricemia was 74.8%, 14.9%, 67.4%, 39.9%, 18.9% and 13.1%, respectively. Female had significantly higher prevalence of dyslipidemia (79.3% vs. 55.9%), diabetes (18.4% vs. 11.4%) and obesity (42.1% vs. 37.7%) than male. Elder subjects (> 75 years) had higher prevalence of hypertension (80.4% vs. 73.4%) than younger ones (65-75 years) while obesity was more prevalent among younger subjects (41.4% vs. 34.1%). Multivariate logistic regression revealed that moderate physical activity and current smoking show beneficial effect on cardiometabolic comorbidities. Higher family income (> 20, 000 CNY/year) was risk factor of diabetes and obesity only while sleep duration between 7 and 8 h/day and married status were risk factors for hypertension only. Current drinking increases the risk of hypertension and dyslipidemia but as protective factor for obesity and stroke.

CONCLUSION

The prevalence of cardiometabolic comorbidities among was high among rural elderly from China. Physical activity, current smoking and drinking, family income, sleep duration and married status were associated with cardiometabolic comorbidities. Metabolic screen was recommended in the older subjects in rural China.

HPA axis and vagus nervous function are involved in impaired insulin secretion of MSG-obese rats

Neuroendocrine dysfunctions such as the hyperactivity of the vagus nerve and hypothalamus-pituitary-adrenal (HPA) axis greatly contribute to obesity and hyperinsulinemia; however, little is known about these dysfunctions in the pancreatic β-cells of obese individuals. We used a hypothalamic-obesity model obtained by neonatal treatment with monosodium l-glutamate (MSG) to induce obesity. To assess the role of the HPA axis and vagal tonus in the genesis of hypercorticosteronemia and hyperinsulinemia in an adult MSG-obese rat model, bilateral adrenalectomy (ADX) and subdiaphragmatic vagotomy (VAG) alone or combined surgeries (ADX-VAG) were performed. To study glucose-induced insulin secretion (GIIS) and the cholinergic insulinotropic process, pancreatic islets were incubated with different glucose concentrations with or without oxotremorine-M, a selective agonist of the M3 muscarinic acetylcholine receptor (M3AChR) subtype. Protein expression of M3AChR in pancreatic islets, corticosteronemia, and vagus nerve activity was also evaluated. Surgeries reduced 80% of the body weight gain. Fasting glucose and insulin were reduced both by ADX and ADX-VAG, whereas VAG was only associated with hyperglycemia. The serum insulin post-glucose stimulation was lower in all animals that underwent an operation. Vagal activity was decreased by 50% in ADX rats. In the highest glucose concentration, both surgeries reduced GIIS by 50%, whereas ADX-VAG decreased by 70%. Additionally, M3AChR activity was recovered by the individual surgeries. M3AChR protein expression was reduced by ADX. Both the adrenal gland and vagus nerve contribute to the hyperinsulinemia in the MSG model, although adrenal is more crucial as it appears to modulate parasympathetic activity and M3AChR expression in obesity.