title: Quality of life and calcium channel blockade with nifedipine GITS versus amlodipine in hypertensive patients in Spain. Gastrointestinal Therapeutic System.
abstract: OBJECTIVE
  Compliance with hypertension treatment is affected by treatment-related factors (complexity, side effects), efficacy and compound-specific effects that impact on quality of life. This study examined the differences in quality of life produced by two once-daily calcium channel blockers using different delivery systems: nifedipine gastrointestinal therapeutic system (GITS) and amlodipine.
  
  
  METHODS
  This was a double-blind, double-dummy, randomized clinical trial comparing nifedipine GITS (30 mg) and amlodipine (5 mg) for 24 weeks following a placebo run-in. Clinical, laboratory evaluations and quality-of-life data were assessed at screening, baseline randomization and three times during active therapy.
  
  
  METHODS
  The study was conducted in 13 medical clinics in Spain.
  
  
  METHODS
  The sample comprised 430 screened and 356 randomized patients with mild to moderate hypertension (diastolic blood pressure 95-114 mmHg).
  
  
  METHODS
  Change in systolic and diastolic blood pressure and in health-related quality of life were the main outcome measures.
  
  
  RESULTS
  There were no significant differences between active treatment groups in the blood pressure changes (systolic blood pressure: nifedipine GITS -15.5 mmHg; amlodipine -15.7 mmHg). Spontaneous adverse events consistent with calcium channel blockage were not different. The nifedipine GITS group improved in all quality-of-life measures except Sexual Symptom Distress and showed a significantly greater improvement than amlodipine in overall Quality of Life (P< 0.05), General Perceived Health (P < 0.026) and its subscale Vitality (P < 0.019). The amlodipine group declined in overall Quality of Life, General Perceived Health, Vitality and Sleep Disturbance, and significantly in Sexual Symptom Distress (P < 0.045). However, this group improved in self-reported Cognitive Functioning (P=0.036), Mental Acuity (P < 0.005) and Detachment/disorientation (P=0.01).
  
  
  CONCLUSIONS
  These results suggest compound-specific effects on quality of life that may be due to differences in the delivery system. Nifedipine GITS is short-acting (2 h half-life) and is delivered continuously over a 24 h period, while amlodipine has a half-life of 40 h, which may produce more sustained low-level effects. While a more beneficial profile was observed for nifedipine, amlodipine demonstrated potential positive effects on cognitive functioning.
authors.affiliation: Department of Biostatistics, Harvard School of Public Health, Boston, Massachusetts, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Testa
authors.forename: R R
authors.initials: RR
authors.lastname: Turner
authors.forename: D C
authors.initials: DC
authors.lastname: Simonson
authors.forename: M B
authors.initials: MB
authors.lastname: Krafcik
authors.forename: C
authors.initials: C
authors.lastname: Calvo
authors.forename: M
authors.initials: M
authors.lastname: Luque-Otero
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D017311:Amlodipine / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000959:Antihypertensive Agents / Q000009:adverse effects; D002121:Calcium Channel Blockers / Q000009:adverse effects / Q000627:therapeutic use*; D004311:Double-Blind Method; D016503:Drug Delivery Systems / Q000009:adverse effects / Q000379:methods; D005260:Female; D006801:Humans; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D009543:Nifedipine / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D011788:Quality of Life; D013030:Spain
chemical_list: D000959:Antihypertensive Agents; D002121:Calcium Channel Blockers; D017311:Amlodipine; D009543:Nifedipine