15 August 2011
MedWire News: Doctors may be able to use certain clinical characteristics
to help identify and improve the care of patients with untreated, under-treated,
or treatment-resistant hypertension, researchers report.
Male gender, a body mass index (BMI) below 25 kg/m2, absence of
chronic kidney disease, a low risk for coronary heart disease, and making few
healthcare visits were associated with untreated hypertension, report Brent Egan
(Medical University of South Carolina, Charleston, USA) and colleagues in the
journal Circulation.
Of the 33 million patients who have uncontrolled hypertension, including
patients who are unaware of their condition and those who are aware, the
majority remain untreated, the team explains.
Moreover, the prevalence of patients with apparent treatment-resistant
hypertension (aTRH; hypertension uncontrolled on three or more, or controlled on
four or more antihypertensive medications) is increasing.
The study included 13,375 hypertensive adults from the National Health and
Nutrition Examination Surveys subdivided into three periods: 1988–1994,
1999–2004, and 2005–2008.
The findings revealed that more than half of patients with uncontrolled
hypertension (defined as a mean systolic blood pressure of ≥140/90 mmHg) were
untreated in each of the three survey periods, including 52.2% of patients in
2005-2008. Multivariate analysis showed that male gender, making 0–1 healthcare
visits per year, absence of chronic kidney disease, having a BMI below 25 kg/m2,
and a Framingham 10-year coronary risk score of less than 10% were significantly
associated with untreated hypertension.
Treated patients with uncontrolled hypertension were significantly more likely
to have a higher Framingham 10-year coronary risk score than those who had
controlled hypertension.
The proportion of treated patients with aTRH increased significantly from 15.9%
in 1998–2004 to 28.0% in 2005–2008, suggesting that a “growing proportion of
hypertensive patients appear to be resistant to treatment,” the authors report.
These patients were significantly more likely to make four or more healthcare
visits annually, be obese, have chronic kidney disease, and have a Framingham
10-year coronary risk score greater than 20%, they continue.
“Integrated healthcare research, policy, and delivery initiatives are needed… to
develop more efficacious antihypertensive agents, and to improve methods for
selecting effective antihypertensive combinations for individual patients,” Egan
et al conclude.
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by Springer Healthcare Limited. © Springer Healthcare Ltd; 2011
Circulation 2011; Advance online publication