Socio-economic status and the therapeutic effectiveness of antihypertensive treatment – the design of the LEO study

OBJECTIVE: The risk of arterial hypertension and subsequent cardiovascular disease morbidity and mortality increases with low socio-economic status (SES). Even small differences in blood pressure, whether untreated or despite treatment, account for this substantial difference. Most of the increased risk in the low socio-economic group is due to traditional cardiovascular risk factors such as overweight and obesity, alcohol consumption and a sedentary life style. Intense treatment of arterial hypertension has been shown to overcome these prognostic inequalities. Therefore, drugs with high efficacy, optimal treatment adherence and a low potential for drug-related side effects are needed in order to reduce the cardiovascular risk burden of patients with a low SES. The angiotensin receptor blocker (ARB) olmesartan will be used to investigate the effectiveness of this drug in different socio-economic classes. RESEARCH DESIGN AND METHODS: The LEO (Long-term Effectiveness of Olmesartan in different Socioeconomic groups) study is a large observational long-term study which has been set up to test the effectiveness of olmesartan within this context. The study has a matched-pairs design (1403 patients in both the low and the high socio-economic classes). MAIN OUTCOME MEASURES: The LEO study will test whether this regimen can reduce the SES-related difference in long-term blood pressure control and compliance in the low SES population. CONCLUSIONS: The study may generate valuable information about the antihypertensive effectiveness of olmesartan alone or in combination with hydrochlorothiazide in different socio-economic classes. It will further test whether the drug helps to reduce the inherent inequalities in cardiovascular prognosis between different socio-economic groups. CURRENT STATUS: The study commenced in July 2007. Results are anticipated in December 2008.