ORIENT: Olmesartan Reducing Incidence of End Stage Renal Disease in Diabetic Nephropathy Trial

Inclusion Criteria: * clinical diagnosis of diabetic nephropathy in patients with type 2 diabetes * albumin-to-creatinine ratio \>= 300 mg/g creatinine in first morning urinalysis * serum creatinine between 1.0 and 2.5 mg/dL in women and between 1.2 and 2.5 mg/dL in men Exclusion Criteria: * type 1 diabetes * non-diabetic nephropathy * history of myocardial infarction * history of cardiac bypass grafting within 3 months * history of percutaneous coronary intervention (PCI) within 6 months * history of carotid artery or peripheral artery revascularization within 6 months * stroke or transient ischemic attack (TIA) within 1 year * unstable angina pectoris * heart failure of NYHA functional classes III or IV * rapid progression of kidney disease within 3 months * severe orthostatic hypotension * serum potassium level =\<3.5 mEq(mmol)/L or =\>5.5 mEq(mmol)L * history of rapid elevation of the serum creatinine level after starting treatment with AII receptor antagonists or ACE inhibitors * poor glycemic control: HbA1c level =\>11% * history of myocardial infarction (MI) or coronary artery bypass grafting (CABG) within 3 months