Vitamin D Deficiency in Patients With Hypertension

Inclusion Criteria: * Men or women over 21 years of age with a history of Stage 1 or 2 hypertension (defined as a seated diastolic BP ≥ 90 mmHg and \< 110 mmHg in the untreated state). * Patients under treatment for hypertension must be willing and able to discontinue any previous antihypertensive medications for the duration of the study. * 25-hydroxyvitamin D levels \< 30 ng/ml and \> 12 ng/ml. * Women of childbearing potential must be using a medically acceptable form of birth control for the duration of the trial, must have a negative serum pregnancy test at screening, and must have a negative urine pregnancy test within 7 days before initiating aliskiren therapy. Exclusion Criteria: * Vitamin D levels \< 12 ng/ml * Known hypersensitivity or allergy to aliskiren * Clinic blood pressure \> 180/110 mmHg * Known forms of secondary hypertension * Chronic atrial fibrillation * Uncontrolled or unstable cardiovascular diseases * Shift or night workers * Mid-arm circumference \> 42 cm in diameter * Current or recent (\<1 year) alcohol or drug abuse * Pregnant or lactating women