OBJECTIVE: It is known that initiation of drug therapy for hypertension, once diagnosed, is now relatively high at around 85%. What is unclear is whether there is a delay between patients being identified with elevated blood pressure and a subsequent diagnosis of hypertension. To address this uncertainty, this database study followed patients with an initial recording of systolic blood pressure greater than 150mmHg, through diagnosis and advice to treatment. METHODS: The DIN-LINK database, containing anonymised medical records from 1.5 million patients collected via GP practice computers, was used to identify and follow-up a cohort of patients with a recorded systolic blood pressure greater than 150mmHg. For inclusion each patient had to have a baseline measurement taken between April 2001 and April 2002, a minimum of 12 months follow-up data and not been diagnosed with hypertension or be prescribed antihypertensive medications prior to the blood pressure measurement. RESULTS: A total of 2880 patients were identified as meeting the criteria. Of these, 1469 (51%) were diagnosed as hypertensive within 12 months, two-thirds of these within one month of the recording of elevated blood pressure. Of the initially identified 2880 patients, only 579 (20%) were prescribed blood pressure lowering medication within 12 months of the initial reading. CONCLUSIONS: For patients who are known to have an elevated blood pressure 49% fail to receive a diagnosis of hypertension and 80% do not receive medication within 12 months of initial reading. Further analyses are required to determine the impact of these delays in diagnosis on patient outcomes.