Blood pressure in middle-aged people in Albury and Melbourne - implications for screening.

Prevalence rates of hypertension and its treatment in two population samples of middle-aged people, one in Albury and one in Melbourne, are described. On average, Italian-born subjects had lower pressures than their Australian-born neighbours. The proportions of Australian-born people in the two centres who had been previously diagnosed were respectively 22% and 32% and the proportions with diastolic blood pressure greater than or equal to 110 mm Hg were 13% and 9%. About one half of the latter had never been told they had high blood pressure. Postal follow-up in the second post-survey year indicated that treatment rates had nearly doubled, many people with relatively low survey pressures stating they were now on therapy. Screening may precipitate over-use of antihypertensive drugs. The recent finding that 80% of middle-aged people in Albury had been to a doctor in the previous 12 months and that in a high proportion the blood pressure had been measured suggests that control of hypertension in Australia may be best achieved by developing surveillance in the context of ordinary medical practice.