Cigarette smoking reduced renal function deterioration in hypertensive patients may be mediated by elevated homocysteine.

Elevated homocysteine (HCY) and smoking are both important risk factors for hypertensive patients. However, whether they have crossing effect on renal function deterioration of hypertensive patients and what is the underlying mechanism are unclear. In the present study, 3033 participants diagnosed as essential hypertension with estimated glomerular filtration rate (eGFR)> 30 ml/min/1.73 m2 from southern China were enrolled in this cross-sectional study. We collected the demographic and clinical data. In addition, the mediation effects were analyzed. The results showed that, comparing with non-smokers, smokers had significant higher levels of HCY (13.10 (11.20-16.87) vs. 11.00 (8.90-13.40) umol/L, P < 0.001) and lower eGFR (79.71 (66.83-91.05) vs. 82.89 (69.80-95.85) ml/min/1.73m2, P < 0.001). HCY levels and smoking were independently associated with decreased eGFR. Meanwhile, eGFR levels were significantly negatively correlated with HCY (P < 0.001), and this correlation might be stronger in current smokers. Current smoker consuming over 20 cigarettes per day would accelerate early renal function deterioration (OR = 1.859, P = 0.019). The mediation effects analysis further showed that the association between smoking and renal function deterioration was mediated by HCY. And elevated HCY was accounted for 56.94% of the estimated causal effect of smoking on renal function deterioration in hypertensive patients. Our findings indicated that cigarette smoking was associated with renal function deterioration in hypertensive patients, and the association between cigarette smoking and renal function deterioration was probably mediated by elevated HCY. Therefore, HCY-lowering therapy may be beneficial for renal function deterioration in hypertensive smoking patients.

[Blood pressure lowering efficacy of telmisartan and amlodipine taking on the morning or at bedtime: ABPM results].

OBJECTIVE: To observe the blood lowering effect of telmisartan and amlodipine taking on the morning or at bedtime in hypertensive patients. METHODS: A total of 108 individuals with hypertension (grade 2 or above) were randomized to receive telmisartan and amlodipine in one of the following four therapeutic schemes: Group A (26 cases): both medications taken on the morning; Group B (28 cases): both medication taken at bedtime; Group C (27 cases): telmisartan on the morning and amlodipine at bedtime; or Group D (27 cases): amlodipine on the morning and telmisartan at bedtime. ABPM was performed before and after 8 weeks treatment. RESULTS: BP was significantly reduced in 4 groups and the value of 24 hours SBP/DBP decline for each group after treatment was 29.94/16.32, 31.37/18.35, 29.49/17.30 and 25.80/15.51 mm Hg (1 mm Hg = 0.133 kPa) respectively (P < 0.05 vs. baseline). SI (smooth index) of 24 hours SBP/DBP was 1.79/1.34, 2.07/1.54, 1.70/1.43 and 1.55/1.32 respectively (P > 0.05). The night-time BP decline and the distributive difference of dipper, non-dipper, extreme dipper and reverse dipper pattern were similar among groups at both baseline and after various treatment regimens (all P > 0.05) . Morning blood pressure surge (MBPS) after treatment in group B declined more significantly than other groups (P < 0.05). CONCLUSION: Telmisartan/amlodipine administered either on the morning or at bedtime can effectively reduce blood pressure. The efficacy of BP lowering is independent of the drug taking time. There is a trend both in better BP lowering and less BP variability when two medications are administered at bedtime.

The diagnostic threshold of HbA1c and impact of its use on diabetes prevalence-a population-based survey of 6898 Han participants from southern China.

OBJECTIVE: The objective of this study is to determine the diagnostic threshold of HbA1c for diabetes and the impact of using it on diabetes prevalence. METHODS: A population-based stratified study was conducted in 2010 among community-dwelling adults aged ≥35years in southern China. Participants without previously-diagnosed diabetes (PDD) took oral glucose tolerance test (OGTT) and HbA1c assay. HbA1c diagnostic threshold was determined by receiver operating characteristic curve. RESULTS: A total of 6989 participants with mean age of 52years were recruited. The area under curve of HbA1c was 0.903 (95% CI: 0.883-0.922), with optimal cut-off value at 6.25% (sensitivity 75.6% and specificity 91.9%). There were 449 (6.42%) patients with PDD and 422 (6.04%), 815 (11.66%) and 918 (13.13%) new cases diagnosed by OGTT, HbA1c ≥6.25% or either, respectively. When either HbA1c or OGTT was used, newly-diagnosed diabetes prevalence increased by 117.4%. CONCLUSIONS: Diabetes is prevalent in southern China. Near half of the patients go undetected with current diagnostic criteria. HbA1c ≥6.25% may be the diagnostic threshold value but needs further verification. The introduction of HbA1c threshold into diabetes diagnosis in China will cause a substantial increase in diabetes prevalence and great challenge on the public healthcare system.

Hemoglobin A1c can identify more cardiovascular and metabolic risk profile in OGTT-negative Chinese population.

OBJECTIVE: To investigate the significance of hemoglobin A1c (HbA1c) in cardiovascular and metabolic risk stratification among diabetes and non-diabetes in southern Chinese. METHODS: Indigenous adults (aged more than or equal to 35 years) without known diabetes were enrolled in the cross-sectional survey. According to oral glucose tolerance test (OGTT), participants were categorized into OGTT-negative group and OGTT-positive group. Cardiovascular and metabolic risk profile was compared between different HbA1c levels (≥ 6.5% vs. < 6.5%) in each group. RESULTS: The prevalence of OGTT-diagnosed diabetes was 6.45% (422/6540). In OGTT-negative group, subjects with HbA1c ≥ 6.5% were older, had higher prevalence of coronary heart disease, current smoking, hypertension, obesity and abdominal obesity. They also had higher body weight, waist-hip ratio, body mass index, glucose levels (fasting plasma glucose, 2-hour plasma glucose and HbA1c), and lipid levels (total cholesterol and low density lipoprotein cholesterol). In OGTT-positive group, patients with HbA1c ≥ 6.5% identified less cardiovascular and metabolic risk file than that in OGTT-negative group. CONCLUSIONS: Subjects with HbA1c ≥ 6.5% have more unfavorable cardiovascular and metabolic risk profile than those with HbA1c < 6.5%, especially in OGTT-negative population. More attention should be paid to this subgroup in clinical practice.