title: Comparative efficacy of irbesartan/ hydrochlorothiazide and valsartan/hydrochlorothiazide combination in lowering blood pressure: a retrospective observational study in Oman.
abstract: OBJECTIVE
  To compare blood pressure (BP) control in patients receiving irbesartan/hydrochlorothiazide (HCTZ) and valsartan/HCTZ at a tertiary care university hospital in Oman.
  
  
  METHODS
  This was a retrospective observational study, where 232 patients' medical records were reviewed during a 3-month period, July to September 2010, at Sultan Qaboos University Hospital in Oman. BP readings of the previous 6 months were also retrieved from the electronic medical records. Analyses were conducted using univariate statistical techniques.
  
  
  RESULTS
  The mean age of the cohort was 58 ± 11 years (range: 21-88). Sixty-nine (30%) patients were on the irbesartan/HCTZ combination (150/12.5 mg) and 163 (70%) were on the valsartan/HCTZ combination. The patients on the valsartan/HCTZ combination were divided into two subgroups: 117 (72%) received 160/12.5 mg and 46 (28%) 80/12.5 mg. Diabetic patients (43/69, 62%, vs. 61/163, 37%, p < 0.001) and those with diabetic nephropathy (8/69, 12%, vs. 7/163, 4%, p = 0.039) were prescribed more often irbesartan/HCTZ than valsartan/HCTZ. In comparison to the valsartan/HCTZ cohort, the irbesartan/HCTZ group was associated with significant reductions in both systolic BP (SBP; -9 vs. -2 mm Hg; p = 0.021) and diastolic BP (DBP; -5 vs. 0 mm Hg; p = 0.022). BP reductions were noted more in diabetics than nondiabetics with the irbesartan/HCTZ patients associated with significant reductions in both SBP (-12 vs. 5.1 mm Hg; p < 0.001) and DBP (-6.4 vs. 1.9 mm Hg; p = 0.001).
  
  
  CONCLUSIONS
  The irbesartan/HCTZ combination was associated with significant reductions in both SBP and DBP when compared with the valsartan/HCTZ combination. Specifically, the reductions were noted more in diabetics than nondiabetics.
authors.affiliation: Department of Pharmacology and Clinical Pharmacy, College of Medicine and Health Sciences, Sultan Qaboos University, Al-Khod, Oman. kal_balushi@hotmail.com
authors.forename: K A
authors.initials: KA
authors.lastname: Al Balushi
authors.forename: J Q
authors.initials: JQ
authors.lastname: Habib
authors.forename: I
authors.initials: I
authors.lastname: Al-Zakwani
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001713:Biphenyl Compounds / Q000008:administration & dosage / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D048909:Diabetes Complications / Q000453:epidemiology; D003920:Diabetes Mellitus / Q000453:epidemiology; D004338:Drug Combinations; D005260:Female; D006801:Humans; D006852:Hydrochlorothiazide / Q000008:administration & dosage / Q000627:therapeutic use*; D006973:Hypertension / Q000188:drug therapy* / Q000453:epidemiology; D000077405:Irbesartan; D008297:Male; D008875:Middle Aged; D009850:Oman / Q000453:epidemiology; D012189:Retrospective Studies; D013777:Tetrazoles / Q000008:administration & dosage / Q000627:therapeutic use*; D014633:Valine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D000068756:Valsartan
chemical_list: D000959:Antihypertensive Agents; D001713:Biphenyl Compounds; D004338:Drug Combinations; D013777:Tetrazoles; D006852:Hydrochlorothiazide; D000068756:Valsartan; D014633:Valine; D000077405:Irbesartan