Toal C B, Mahon W A, Barnes C, Burelle D
Bayer Inc., Etobicoke, Ontario, Canada.
Clin Ther. 1997 Sep-Oct;19(5):924-35. doi: 10.1016/s0149-2918(97)80046-x.
Nifedipine gastrointestinal therapeutic system (GITS) is an extended-release dosage formulation that provides sustained blood concentrations of nifedipine over 24 hours. A 20-week, postmarketing surveillance study of the effectiveness and patient tolerability of nifedipine GITS 30 or 60 mg was conducted in the offices of 187 Canadian general practitioners from September 1992 to March 1994. A total of 1700 patients previously or newly diagnosed with mild-to-moderate essential hypertension (sitting diastolic blood pressure, 95 to 114 mm Hg) were included. The 20-week treatment period was completed by 1326 patients. Patients received nifedipine GITS 30 mg initially; the dose could be titrated upward to 60 mg after 3 and 6 weeks. Of all patients entered, 605 (35.6%) reported one or more adverse events. The three most frequently occurring adverse events were headache (12.2%), peripheral edema (8.1%), and dizziness (2.9%). The frequency of adverse events was highest in the first 3 weeks and decreased subsequently. The overall incidence of adverse events was 29.8% in patients receiving 30 mg of nifedipine GITS and 25.3% in those receiving 60 mg; adverse events were the cause of study discontinuation in 12.3% of patients. The overall health status of patients as measured by the SF-36 questionnaire was comparable to that previously reported for healthy individuals. At baseline, mean (+/- SE) systolic/diastolic blood pressure values for all patients were 160.1 +/- 0.4/97.4 +/- 0.2 mm Hg. Final blood pressure readings after 20 weeks of treatment in the 30-mg group (141.5 +/- 0.4/84.8 +/- 0.2 mm Hg) and the 60-mg group (146.6 +/- 0.8/88.8 +/- 0.4 mm Hg) were significantly decreased from baseline. At week 20, the 30-mg dose was sufficient to maintain blood pressure in 74.5% of patients; 25.5% of patients required 60 mg. Subgroup analysis revealed similar responses in patients who had received blood pressure medication before study initiation and those who had not. Response was also independent of age and type of previous antihypertensive therapy. In general medical practice, the 30-mg and 60-mg doses of nifedipine GITS were both effective and well tolerated and had minimal or no negative effects on the overall health status of treated individuals.
硝苯地平胃肠道治疗系统（GITS）是一种缓释剂型，可在24小时内维持硝苯地平的血药浓度。1992年9月至1994年3月，在187名加拿大全科医生的诊所中进行了一项为期20周的上市后监测研究，以评估30毫克或60毫克硝苯地平GITS的有效性和患者耐受性。总共纳入了1700例先前或新诊断为轻度至中度原发性高血压（坐位舒张压为95至114毫米汞柱）的患者。1326例患者完成了20周的治疗期。患者最初接受30毫克硝苯地平GITS治疗；3周和6周后剂量可上调至60毫克。在所有入组患者中，605例（35.6%）报告了一种或多种不良事件。最常出现的三种不良事件是头痛（12.2%）、外周水肿（8.1%）和头晕（2.9%）。不良事件的发生率在最初3周最高，随后下降。接受30毫克硝苯地平GITS的患者不良事件总发生率为29.8%，接受60毫克的患者为25.3%；不良事件是12.3%患者停药的原因。通过SF-36问卷测量的患者总体健康状况与先前报道的健康个体相当。基线时，所有患者的平均（±标准误）收缩压/舒张压值为160.1±0.4/97.4±0.2毫米汞柱。30毫克组（141.5±0.4/84.8±0.2毫米汞柱）和60毫克组（146.6±0.8/88.8±0.4毫米汞柱）在治疗20周后的最终血压读数较基线显著降低。在第20周时，30毫克剂量足以维持74.5%患者的血压；25.5%的患者需要60毫克。亚组分析显示，在研究开始前接受过降压药物治疗的患者和未接受过治疗的患者中，反应相似。反应也与年龄和先前的抗高血压治疗类型无关。在一般医疗实践中，30毫克和60毫克剂量的硝苯地平GITS均有效且耐受性良好，对接受治疗个体的总体健康状况影响极小或无负面影响。
