Tao Yuan, Lanping Jiang, Chen Chen, Xiaoyan Peng, Min Nie, Xuemei Li, Xiaoping Xing, Xuewang Li and Limeng Chen
Impaired glucose metabolism and insulin sensitivity have been reported in patients with Gitelman syndrome (GS), but insulin secretion and the related mechanisms are not well understood.
Design and methods
The serum glucose levels, insulin secretion and insulin sensitivity were evaluated in patients with GS (n = 28), patients with type 2 diabetes mellitus (DM) and healthy individuals (n = 20 in both groups) using an oral glucose tolerance test. Serum and urine sodium, potassium and creatinine levels were measured at 0, 30, 60, 120 and 180 min after an oral glucose load was administered.
The areas under the serum glucose curves were higher in the GS patients than those in the healthy controls (17.4 ± 5.1 mmol·h/L vs 14.5 ± 2.8 mmol·h/L, P = 0.02) but lower than those in the DM patients (24.8 ± 5.3 mmol·h/L, P < 0.001). The areas under the serum insulin curves and the insulin secretion indexes in GS patients were higher than those in DM patients and lower than those in healthy subjects. The insulin secretion-sensitivity index of GS patients was between that of healthy subjects and DM patients, but the insulin sensitivity indices were not different among the three groups. After one hour of glucose administration, the serum potassium level significantly decreased from baseline, and the urinary potassium-to-creatinine ratio increased gradually and peaked at 2 h.
Glucose metabolism and insulin secretion were impaired in GS patients, but insulin sensitivity was comparable between GS patients and patients with type 2 DM. After administration of an oral glucose load, the plasma potassium level decreased in GS patients due to the increased excretion of potassium in the urine.
Xue-Jiao Yang, Le-Yang Zhang, Qing-Hua Ma, Hong-Peng Sun, Yong Xu, Xing Chen and Chen-Wei Pan
We aimed to examine the associations of platelet parameters with the presence of metabolic syndrome in community-dwelling older Chinese adults.
Study sample was from the Weitang Geriatric Diseases Study, which included 4338 individuals aged 60 years or above. The mean age of the participants was 68 years. Metabolic syndrome was defined based on the Adult Treatment Panel III criteria. Platelet parameters were assessed using an automated hematology analyzer. Multiple logistic regression models were fitted to examine relationships between the platelet parameters and the presence of metabolic syndrome after adjusting for potential confounders.
The adjusted odds ratio (95% CI) of metabolic syndrome for the highest quartile of platelet parameters (platelet count, mean platelet volume, plateletcrit, platelet distribution width, platelet larger cell ratio) when compared to the lowest quartile were 1.32 (1.06, 1.64), 1.00 (0.81, 1.24), 1.37 (1.10, 1.71), 1.45 (1.14, 1.83), 1.11 (0.89, 1.39), respectively. Hypertension and diabetes modified the relationship between platelet distribution width and metabolic syndrome with the associations being significant in hypertensive and non-diabetic groups. The levels of platelet distribution width increased with the risk of metabolic syndrome in men but not in women.
The levels of platelet count, plateletcrit and platelet distribution width increased in older adults with metabolic syndrome, suggesting that these parameters may be useful biomarkers for further risk appraisal of metabolic syndrome in aged population.