Over four million California adults age 45 and older have high blood pressure.

Nearly 40% of California adults age 45 and older reported being diagnosed with high blood pressure, according to the 2001 California Health Interview Survey (CHIS 2001). High blood pressure, also called hypertension, is known as "the silent killer" because it often has no symptoms. If left unchecked and untreated, uncontrolled high blood pressure can lead to heart failure, kidney failure, heart attack and stroke. This policy brief provides data of diagnosed high blood pressure rates for California legislative districts and counties for adults age 45 and older. The first of its kind subcounty data in this policy brief are estimates created by a small-area methodology, based on rates from CHIS 2001 that are applied to population data from the 2000 Census and 2002 California Department of Finance.