Trends in the prevalence, awareness, treatment and control of hypertension in Geneva, Switzerland, from 1999 to 2009

Idris Guessous, Murielle Bochud, Jean-Marc Theler, Jean-Michel Gaspoz, Antoinette Pechère-Bertschi
1999-2009 Trends in prevalence, unawareness, treatment and control of hypertension in Geneva, Switzerland, PLoS One, 27 June 2012, doi: /10.1371/journal.pone.0039877

Abstract

Background: There are no temporal trends in the prevalence, unawareness, treatment and control of hypertension in Switzerland. The aim of this study was to analyse these trends and identify associated factors.

Methods: Population-based study conducted in the canton of Geneva, Switzerland, between 1999 and 2009. Blood pressure was measured three times according to a standard protocol. Hypertension was defined as mean systolic or diastolic blood pressure ≥ 140/90 mmHg, or self-reported hypertension, or antihypertensive treatment. Unawareness of hypertension, untreated hypertension, and uncontrolled hypertension were determined by questionnaires and blood pressure measurements. Age-standardised annual prevalences and adjusted associations for the 1999-2003 and 2004-2009 survey periods were reported. The ten-year study included 9,215 participants aged between 35 and 74. 

Results: The prevalence of hypertension remained stable (34.4%). Unawareness of hypertension fell from 35.9% to 17.7% (P < 0.001). This decrease in unawareness of hypertension was not accompanied by a concomitant increase in treatment of hypertension, which remained low (38.2%). A greater proportion of all hypertensive participants were aware but untreated in 2004-2009 (43.7%) compared with 1999-2003 (33.1%). Uncontrolled hypertension improved from 62.2% to 40.6% between 1999 and 2009 (P = 0.02). During the 1999-2003 period, the factors associated with undetected hypertension were active smoking (OR = 1.27, 95% CI 1.02-1.59), male sex (OR = 1.56, 1.27-1.92), hypercholesterolaemia (OR = 1.31, 1.20-1.44) and advanced age (OR 65-74 years vs 35-49 years = 1.56, 1.21-2.02). In 1999-2003 and 2004-2009, obesity and diabetes were negatively associated with unawareness of hypertension, high education was associated with untreated hypertension (OR = 1.45, 1.12-1.88 and 1.42, 1.02-1.99, respectively), and male sex was associated with uncontrolled hypertension (OR = 1.49, 1.03-2.17 and 1.65, 1.08-2.50, respectively). A sedentary lifestyle was associated with a higher risk of hypertension and uncontrolled hypertension in 1999-2003.

Conclusions: The prevalence of hypertension has remained stable since 1999 in the canton of Geneva. Although awareness of hypertension has fallen considerably, more than half of hypertensive subjects remained untreated or uncontrolled in 2004-2009. This study has identified determinants that should guide interventions aimed at improving the treatment and control of hypertension.

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