Evaluation of blood pressure lowering effect by generic and brand-name antihypertensive drugs treatment: a multicenter prospective study in China.

BACKGROUND: Generic drugs are bioequivalent to their brand-name counterparts; however, concerns still exist regarding the effectiveness and safety of generic drugs because of small sample sizes and short follow-up time in most studies. The purpose of this study was to evaluate the long-term antihypertensive efficacy, cost-effectiveness and cardiovascular outcomes of generic drugs compared with brand-name drugs. METHODS: In a multicenter, community-based study including 7955 hypertensive patients who were prospectively followed up for an average of 2.5 years, we used the propensity-score-matching method to match the patients using brand-name drugs to those using generic drugs in a ratio of 1:2, 2176 patients using brand-name drugs and 4352 patients using generic drugs. RESULTS: There were no significant differences between generic drugs and brand-name drugs in blood pressure (BP)-lowering efficacy, BP control rate, and cardiovascular outcomes including coronary heart disease and stroke. The adjusted mean (95% confidence interval [CI]) of systolic BP (SBP)-lowering was -7.9 mmHg (95% CI, -9.9 to -5.9) in the brand-name drug group and -7.1 mmHg (95% CI, -9.1 to -5.1) in the generic drug group after adjusting for age, sex, body mass index, number of antihypertensive drugs and traditionally cardiovascular risk factors. Among patients aged <60 years, brand-name drugs had a higher BP control rate (47% vs. 41%; P = 0.02) and a greater effect in lowering SBP compared with generic drugs, with the between-group difference of 1.5 mmHg (95% CI, 0.2-2.8; P = 0.03). BP control rate was higher in male patients using brand-name drugs compared with those using generic drugs (46% vs. 40%; P = 0.01). Generic drugs treatment yielded an average annual incremental cost-effectiveness ratio of $315.4 per patient per mmHg decrease in SBP compared with brand-name drugs treatment. CONCLUSIONS: Our data suggested that generic drugs are suitable and cost-effective in improving hypertension management and facilitating public health benefits, especially in low- and middle-income areas.

Supplementation of folic acid and vitamin B12 reduces plasma levels of asymmetric dimethylarginine in patients with acute ischemic stroke.

Increased levels of asymmetric dimethylarginine (ADMA) have been observed in patients with acute ischemic stroke. We aimed to investigate the correlation between ADMA and ischemic stroke, and evaluate the effect of supplementation of folic acid and vitamin B12 on concentrations of ADMA. Patients were randomized into intervention and non-intervention groups within 3 days after symptom onset. Intervention group patients were treated with folic acid (5mg daily) and vitamin B12 (500 µg twice daily) for 12 weeks. ADMA and homocysteine (Hcy) concentrations were measured before treatment (baseline) and 2 and 12 weeks after treatment. The laboratory measures were also collected from healthy controls. Eighty five subjects were enrolled in this study, from whom 72 with complete baseline and follow-up laboratory data were included in the present analysis. Thirty four patients were assigned to the intervention group and 38 patients to the non-intervention group. Sixty people were enrolled as healthy controls. Levels of ADMA and Hcy were raised (p<0.05) in patients with acute ischemic stroke. With supplementation of both folic acid and vitamin B12, the levels of ADMA and Hcy decreased significantly at 2 and 12 weeks (p<0.05). The present study reconfirmed that ADMA can be regarded as a risk biomarker for acute ischemic stroke. We observed that with supplementation of folic acid and vitamin B12, levels of ADMA were decreased in patients with acute ischemic stroke.

[Impact of adding folic acid, vitamin B(12) and probucol to standard antihypertensive medication on plasma homocysteine and asymmetric dimethylarginine levels of essential hypertension patients].

OBJECTIVE: To investigate the impact of adding folic acid, vitamin B(12) and probucol to standard antihypertensive medication on plasma homocysteine (Hcy) and asymmetric dimethylarginine (ADMA), serum NO and eNOS of essential hypertensive patients. METHOD: A total of 120 patients with hypertension were randomly divided to three groups (n = 40 each): group 1 (standard medication), group 2 (adding folic acid 5 mg/day and vitamin B(12) 500 µg twice daily) and group 3 (adding folic acid 5 mg/day and vitamin B(12) 500 µg twice daily and probucol 500 mg twice daily). Plasma Hcy and ADMA, serum NO and eNOS levels were observed at baseline, 2 and 12 weeks after various therapy. RESULTS: In group 1, concentrations of plasma Hcy [(23.06 ± 14.15) µmol/L, (23.67 ± 12.31) µmol/L, (23.25 ± 11.64) µmol/L], ADMA [(0.21 ± 0.12) µmol/L, (0.23 ± 0.13) µmol/L, (0.21 ± 0.09) µmol/L] and serum NO [(64.14 ± 15.07) µmol/L, (65.29 ± 15.04) µmol/L, (65.32 ± 13.58) µmol/L], eNOS [(20.02 ± 4.50) µg/L, (20.79 ± 4.03) µg/L, (19.82 ± 5.70) µg/L] remained unchanged during the 12 weeks therapy (all P > 0.05). In group 2, concentrations of plasma Hcy [(12.54 ± 6.49) µmol/L] and ADMA[(0.18 ± 0.07) µmol/L] were significantly decreased after the treatment of 12 weeks than the treatment baseline value [(21.51 ± 7.82) µmol/L, (0.20 ± 0.12) µmol/L] and 2 weeks value[(19.38 ± 8.14) µmol/L, (0.21 ± 0.12) µmol/L], however the concentrations of serum NO and eNOS showed contrary results of the Hcy and ADMA's. (all P < 0.05). In group 3, similar changes occurred at 2 weeks after therapy (P < 0.05 2 weeks vs. baseline and 12 weeks vs. 2 weeks). Plasma ADMA level was positively correlated with Hcy at baseline (r = 0.546, P < 0.05). CONCLUSIONS: Supplementation of folic acid, VitB(12) and/or probucol helps to improve endothelial function and reduce plasma Hcy and ADMA levels in patients with hypertension.