Plasma asymmetric dimethylarginine and cystatin C levels in patients with coronary artery disease / 中华心血管病杂志

<p><b>OBJECTIVE</b>To compare plasma asymmetric dimethylarginine (ADMA), an endogenous nitric oxide synthase inhibitor, and cystatin C levels in patients with or without coronary artery disease (CAD).</p><p><b>METHODS</b>We recruited 87 CAD patients (39 with acute myocardial infarction and 48 with unstable angina pectoris) and 51 non-CAD controls. Plasma ADMA was measured by HPLC, cystatin C by particle-enhanced immunonephelometric assay (N Latex cystatin C, Dade Behring) with nephelometer (BNII, Dade Behring). CAD patients were further divided into low cystatin C group (< 1.0 mg/L, 36 cases) and high cystatin C group (> 1.0 mg/L, 51 cases).</p><p><b>RESULTS</b>(1) The plasma levels of ADMA [(0.47 ± 0.15) µmol/L vs. (0.37 ± 0.15) µmol/L], SDMA [(0.39 ± 0.19) µmol/L vs. (0.28 ± 0.12) µmol/L] and cystatin C [(1.16 ± 0.32) mg/L vs. (0.73 ± 0.16) mg/L] were significantly higher in CAD patients than in controls (all P < 0.05). The plasma L-Arg was significantly lower in CAD patients than in controls [(59.4 ± 19.4) µmol/L vs. (83.7 ± 19.6) µmol/L, P < 0.05]. (2) Plasma ADMA was similar in CAD patients with low cystatin C level and controls [(0.42 ± 0.12) µmol/L vs. (0.39 ± 0.15) µmol/L, P = 0.251] and Plasma ADMA was significantly higher in CAD patients with high cystatin C level than in controls [(0.50 ± 0.17) µmol/L vs. (0.39 ± 0.15) µmol/L, P < 0.05].</p><p><b>CONCLUSION</b>ADMA levels were significantly increased only in CAD patients with elevated cystatin C levels but not in CAD patients with normal renal function. The reported relationship between coronary heart disease and ADMA may not be direct, but could be secondary due to reduced renal function.</p>

Aldosterone/plasma renin activity ratio is a sensitive parameter for screening patients with primary aldosteronism / 中华心血管病杂志

<p><b>OBJECTIVE</b>To screen primary aldosteronism cases with ARR (aldosterone/plasma renin activity, ARR) from patients with hypertension, and to evaluate the diagnosis value of ARR in primary aldosteronism cases and analysis the clinical characters of primary aldosteronism cases.</p><p><b>METHODS</b>Nine hundred and two patients with hypertension were collected, the plasma aldosterone concentration to plasma renin activity ratio were detected by radio-immunity method, after that, ARR were calculated. Retrospective analysis was made of clinical data in 126 primary aldosteronism cases, which ARR were over 25.</p><p><b>RESULTS</b>One hundred and twenty-six cases (14%) were diagnosed as primary aldosteronism, and of them, 49 cases had hypokalemia. 25 patients received surgical operation and the rate of efficiency and cure of surgery treatment were 100% and 48%, respectively. The rate of efficiency and cure of drug treatment was 89% and 24% respectively.</p><p><b>CONCLUSIONS</b>Primary aldosteronism affects over 10% of patients with hypertension in China. Patients with hypertension and most patients with treatment-resistant hypertension should undergo screening for primary aldosteronism with ARR. A high ARR is a positive screening test result, a finding that warrants confirmatory testing.</p>

Study on the distribution of serum homocysteine and on multi-stepwise regression analysis of the associated factors in the population of community areas in Wuhan / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the serum homocysteine (Hcy) distribution and characteristics in different sex and age groups in the community residents in Wuhan, and to analyse its associated factors with multi-stepwise regression analysis.</p><p><b>METHODS</b>The population under study was from three community areas in Wuhan. Demographic distribution and the correlation with other risk factors of serum Hcy were analyzed statistically.</p><p><b>RESULTS</b>(1) Geometric mean of serum Hcy was 14.43 micromol/L in males and 10.89 micromol/L in females with P <0.001. (2) Hcy of per age level in males was also higher (P <0.001). (3) The prevalence rate of hyperhomocysteinemia was 23.94% in the general population in Wuhan. The prevalence rate of hyperhomocysteinemia in males was 2.62 times higher than in females. (4) Multi-stepwise regression analysis showed that Hcy had different affecting factors in males and females. The affecting factors of Hcy in males were daily cigarettes smoking, urine micro-albumin (UMALB) and times of exercise per week. The affecting factors of Hcy in females were duration of exercise each time, weight, triglyceride (TG), high-density lipoprotein (HDL), urine micro-albumin (UMALB) and age.</p><p><b>CONCLUSIONS</b>(1) Hcy at the population level was significantly different by sex and age. (2) Population living in the community in Wuhan had a higher serum level and prevalence rate of Hcy comparing to some other cities in China and even in developed countries. (3) The important affecting factors of Hcy in population also showed sex difference, unlike the reports from other countries or other areas in China. Serum Hcy seemed to be affected by environmental and other factors.</p>

A case-control study on the relationship between stroke and plasma homocysteine level and the mutation of MTHFR gene / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the relationship of stroke and plasma homocysteine (Hcy) level and the mutation of methylenetetrahydrofolate reductase (MTHFR) gene.</p><p><b>METHODS</b>Three hundred patients with stroke were included as the case group in this study while 300 subjects without stroke matched with the case group for sex and age were collected as the control group. Plasma Hcy level was measured using HPLC and MTHFR 667C-->T mutant was determined by polymerase chain reaction and restriction fragment analysis. The relationship of stroke and plasma Hcy level and the mutation of MTHFR gene was then analysed.</p><p><b>RESULTS</b>The plasma Hcy level of the case group was significantly higher than that of the control group (16.92 +/- 3.43 micromol/L vs. 14.57 +/- 2.59 micromol/L, P <0.05). There was no significant difference in mutation rate of MTHFR C677T between stroke group and control group (P >0.05), as well as between ischemic stroke group and homorrhagic stroke group (P >0.05). The mutation of MTHFR C677T had no significant influence on the Hcy level (15.28 +/- 2.17 micromol/L vs. 15.11 +/- 3.81 micromol/L, P >0.05).</p><p><b>CONCLUSION</b>Increased plasma Hcy level played an important role in the occurrence of stroke in Chinese people, and the mutation of MTHFR C677T was not associated with Hcy level or stroke which led to the speculation that plasma Hcy level was important in the prevention of cardio-cerebro-vascular diseases among Chinese people.</p>