Effect of folic acid supplementation on the change of plasma S-adenosylhomocysteine level in Chinese hypertensive patients: a randomized, double-blind, controlled clinical trial.

The relationship between folic acid and S-adenosylhomocysteine (SAH) is controversial. This study aims to explore the effect of different doses of folic acid supplementation on SAH levels in hypertensive patients and the modification of methylene-tetrahydrofolate reductase (MTHFR) C677T gene polymorphism. A randomized, double-blind, controlled clinical trial was conducted. Hypertensive patients aged 45-75 years without a history of stroke and cardiovascular disease were selected, who were randomly assigned to one of 8 dose groups. This trial has been registered with Trial Number: ChiCTR1800016135. In the total population, folic acid supplementation of 0.4-2.0 mg/day had no effect on SAH level (ß = 0.47, 95% CI: -0.86-1.79, p = 0.491), while folic acid supplementation of 2.4 mg/day significantly increased SAH level (ß = 1.93, 95% CI: 0.22-3.64, p = 0.027). Stratified analysis found that MTHFR C677T genotype CC supplemented with 2.4 mg/day folic acid had no effect on SAH level (ß = 0.30, 95% CI: -2.74-3.34, p = 0.847), while CT and TT genotype supplemented with 2.4 mg/day folic acid showed a significant increase in SAH level (CT: ß = 2.98, 95% CI: 0.34-5.62, p = 0.027; TT: ß = 3.00, 95% CI: -0.51-6.51, p = 0.095; CT combined with TT: ß = 2.99, 95% CI: 0.90-5.09, p = 0.005). In conclusion, supplementation of 2.4 mg/day folic acid can lead to increased SAH levels, especially in MTHFR C677T genotype CT and TT.

Association between Body Mass Index and All-Cause Mortality in Hypertensive Adults: Results from the China Stroke Primary Prevention Trial (CSPPT).

The association between elevated body mass index (BMI) and risk of death has been reported in many studies. However, the association between BMI and all-cause mortality for hypertensive Chinese adults remains unclear. We conducted a post-hoc analysis using data from the China Stroke Primary Prevention Trial (CSPPT). Cox regression analysis was performed to determine the significance of the association of BMI with all-cause mortality. During a mean follow-up duration of 4.5 years, 622 deaths (3.0%) occurred among the 20,694 participants aged 45-75 years. A reversed J-shaped relationship was observed between BMI and all-cause mortality. The hazard ratios (HRs) for underweight (<18.5 kg/m²), overweight (24.0-27.9 kg/m²), and obesity (≥28.0 kg/m²) were calculated relative to normal weight (18.5-23.9 kg/m²). The summary HRs were 1.56 (95% CI, 1.11-2.18) for underweight, 0.78 (95% CI 0.64-0.95) for overweight and 0.64 (95% CI, 0.48-0.85) for obesity. In sex-age-specific analyses, participants over 60 years of age had optimal BMI in the obesity classification and the results were consistent in both males and females. Relative to normal weight, underweight was associated with significantly higher mortality. Excessive weight was not associated with increased risk of mortality. Chinese hypertensive adults had the lowest mortality in grade 1 obesity.

SLCO1B1 Variants and Angiotensin Converting Enzyme Inhibitor (Enalapril)-Induced Cough: a Pharmacogenetic Study.

Clinical observations suggest that incidence of cough in Chinese taking angiotensin converting enzyme inhibitors is much higher than other racial groups. Cough is the most common adverse reaction of enalapril. We investigate whether SLCO1B1 genetic polymorphisms, previously reported to be important determinants of inter-individual variability in enalapril pharmacokinetics, are associated with the enalapril-induced cough. A cohort of 450 patients with essential hypertension taking 10 mg enalapril maleate were genotyped for the functional SLCO1B1 variants, 388A > G (Asn130Asp, rs2306283) and 521T > C (Val174Ala, rs4149056). The primary endpoint was cough, which was recorded when participants were bothered by cough and respiratory symptoms during enalapril treatment without an identifiable cause. SLCO1B1 521C allele conferred a 2-fold relative risk of enalapril-induced cough (95% confidence interval [CI] = 1.34-3.04, P = 6.2 × 10(-4)), and haplotype analysis suggested the relative risk of cough was 6.94-fold (95% CI = 1.30-37.07, P = 0.020) in SLCO1B1*15/*15 carriers. Furthermore, there was strong evidence for a gene-dose effect (percent with cough in those with 0, 1, or 2 copy of the 521C allele: 28.2%, 42.5%, and 71.4%, trend P = 6.6 × 10(-4)). Our study highlights, for the first time, SLCO1B1 variants are strongly associated with an increased risk of enalapril-induced cough. The findings will be useful to provide pharmacogenetic markers for enalapril treatment.

Rs495828 polymorphism of the ABO gene is a predictor of enalapril-induced cough in Chinese patients with essential hypertension.

OBJECTIVE: ABO genetic polymorphisms have recently been associated with angiotensin-converting enzyme (ACE) activity and inflammation, which play a critical role in the pathogenic mechanism of ACE inhibitor-induced cough. Therefore, the current study determined the association of ABO genetic polymorphisms with enalapril-induced cough in Chinese patients with essential hypertension. METHODS: A total of 450 essential hypertensive patients treated with 10 mg of enalapril maleate were genotyped for ABO genetic polymorphisms using the PCR-direct sequencing method. Cough was recorded when patients were bothered by cough and respiratory symptoms during enalapril treatment without an identifiable cause. RESULTS: The distribution of rs8176740 and rs495828 was different between the coughers and the controls [P=0.039; odds ratio (OR)=0.70, P=0.018; OR=1.41]. The risk of enalapril-induced cough in the rs495828 TT carriers was increased (P=0.008; OR=2.69), which remained significant after false discovery rate correction. The results for the rs8176740 polymorphism were significant in the female subgroup (P=0.027; OR=0.22). Haplotype analysis of the four ABO polymorphisms (rs8176746/rs8176740/rs495828/rs12683493) showed that the frequency of the GATC haplotype was higher in the coughers than those in the controls (26.6 vs. 18.8%, P=0.033; OR=1.43). CONCLUSION: The rs495828 polymorphism was associated with enalapril-induced cough and may serve as a useful pharmacogenomics marker of the safety of enalapril in Chinese patients with essential hypertension. The mechanism for the associations may involve the effects of the ABO gene or ABO blood type on ACE activity and inflammation.

Effect of NR3C2 genetic polymorphisms on the blood pressure response to enalapril treatment.

AIM: The mineralocorticoid receptor (MR; also known as NR3C2) plays important roles in the modulation of blood pressure. The effect of NR3C2 polymorphisms on antihypertensive response to enalapril was investigated. PATIENTS & METHODS: Two hundred and seventy nine essential hypertension patients treated with enalapril were genotyped for two NR3C2 tagSNPs, rs5522 and rs2070950, by Sequenom MassArray™ technology. RESULTS: The reductions in diastolic blood pressure (DBP) were significantly greater in AA homozygotes compared with AG+GG genotype carriers for the rs5522 polymorphism (p = 0.009), and the reductions in DBP were greater in GG homozygotes compared with GC+CC genotype carriers for the rs2070950 polymorphism, with marginal significance (p = 0.065). Stepwise multiple regression analysis indicated that significant predictors of DBP reduction were baseline DBP (p < 0.001), waist:hip ratio (p = 0.001) and rs5522 genotype (p = 0.003). CONCLUSION: NR3C2 rs5522 affects blood pressure response to enalapril treatment and may serve as a useful pharmacogenomic marker of antihypertensive response to enalapril in essential hypertension patients.

Prevalence estimates for primary brain tumors in China: a multi-center cross-sectional study.

BACKGROUND: Although the first leading cause of death in China was malignant neoplasms (mortality, 374.1 per 100,000 person-years), the full impact of primary brain tumors (PBT) on the healthcare system is not completely described because there are a few well documented reports about the epidemiologic features of brain tumors. This study aimed to report a comprehensive assessment on the prevalence of PBT. METHODS: A multicenter cross-sectional study on brain tumor (MCSBT) in China was initiated in five regional centers: Daqing (northeast), Puyang (north of China), Shiyan (center of China), Ma'anshan (center of China) and Shanghai (southeast). Prevalence rate was calculated by counting the number of people living with a PBT between October 1, 2005 and September 30, 2006 and dividing by the total population of the five communities at January 1, 2006. Estimates of prevalence were expressed as percentages and grouped according to gender and to age in fifteen-year categories. Within these strata, the rates were estimated with 95% confidence intervals (CI) using the accurate calculation of CI for Poisson distribution. A chi-square test was used to compare the various frequencies with α < 0.05. Age-standardized prevalence with the direct method was calculated with the ten-year age-specific prevalence and the age distribution of the Chinese population in 2010, obtained from World population prospects: the 2008 revision. RESULTS: We estimated that the overall prevalence of PBT was 24.56 per 100,000 (95%CI, 14.85 to 34.27), and the overall prevalence of PBT in female population (30.57 per 100,000 and its 95%CI ranged from 19.73 to 41.41) was higher than that in male population (18.84 per 100,000 and its 95%CI ranged from 10.33 to 27.35). However, the discrepancy between genders was not statistically significant because the 95%CI overlapped. Of 272 cases of newly diagnosed PBT, the proportion of histological subtypes by age groups, gender was statistically different (χ(2) = 52.6510, P < 0.0001). More than half of all reported tumors (52.57%) were either gliomas or meningiomas. For the youngest (aged from 0 - 19) strata of the population, glioma appeared to occur more than other subtypes, accounting for 55.56% of all of cases. The majority of brain tumors presented in those aged from 20 to 59 years was pituitary adenomas (45.12%) and gliomas (31.10%). Opposed to brain tumors in adults and teenage, gliomas only accounted for 22.22%. Meanwhile, the median ages at diagnosis of the patients with PBT were similar between males and females except for pituitary adenomas (male: 59 years old; female: 45 years old). CONCLUSIONS: Age standardized prevalence of PBT is 22.52 per 100,000 (95%CI, 13.22 to 31.82) for all populations, 17.64 per 100,000 (95%CI, 9.41 to 25.87) for men, and 27.94 per 100,000 (95%CI, 17.58 to 38.30) for women. Age standardization to China's 2010 population yielded an estimated population of 304 954 cases with PBT. Our prevalence estimates provide a conservative basis on which to plan health care services and to develop programmatic strategies for surviving. In the future, it would be helpful to have long-term observed survival rates that would make the assumptions and the resulting imprecision in the current estimates unnecessary.

[Efficacy of enalapril combined with folic acid in lowering blood pressure and plasma homocysteine level].

OBJECTIVE: To investigate the efficacy of enalapril combined with folic acid in lowering both blood pressure and plasma total homocysteine (Hcy) in essential hypertensive patients. METHODS: A randomized, community-based clinical trial was conducted. Subjects with hypertension were randomly assigned to one of three treatment groups:enalapril 10 mg/d alone (control), enalapril 10 mg plus folic acid 0.4 mg daily (low-dose group) and enalapril 10 mg combined with folic acid 0.8 mg daily (high-dose group) for a total of 8 weeks. Resting blood pressures of all subjects was measured at baseline, 2nd, 4th, 6th and 8th week of therapy. Plasma Hcy levels were measured at baseline, 4 week and the end of study. RESULTS: A total of 273 hypertensive patients were enrolled. All analyses were performed according to the intention to treat. Compared with control group, both low- and high-dose group had significantly a greater efficacy in lowering both blood pressure and plasma Hcy level, or in lowering either blood pressure or plasma Hcy level, or in lowering Hcy level. The proportion of subjects showing a marked reduction in both blood pressure and plasma homocysteine in control group, low-dose group and high-dose group were 3.8%, 15.2% and 17.1% respectively; the proportion of subjects showing a marked reduction in either blood pressure or plasma homocysteine in control group, low-dose group and high-dose group were 43.8%, 70.9% and 58.5% respectively. Effect upon blood pressure lowering was not significantly different among these three regimens. CONCLUSION: As compared to enalapril alone, enalapril combined with folic acid showed a better efficacy in reducing both blood pressure and plasma Hcy level in hypertensive subjects.