Undiagnosed obesity in hypertension: clinical and therapeutic implications

The aim of this study was to determine the prevalence of obesity in patients with hypertension and to evaluate the relationship between obesity, metabolic syndrome (MetS) and blood pressure (BP) control.

We conducted an epidemiological survey in a sample of 19,039 patients with hypertension who consecutively attended a primary healthcare center. Patients were considered to have hypertension if the BP was > or =140/90 mmHg or > or =130/80 mmHg in diabetic patients or if they were undergoing pharmacological treatment for hypertension. The obesity was based on body mass index (BMI). Overweight was if the BMI was > or =25 kg/m2, obese > or =30 kg/m2 and severe obesity (SO) if BMI was > or =40 kg/m2. Abdominal obesity (AO) was considered when the waist circumference was greater than 102 cm in men and 88 cm in women.

The prevalence of obesity in our hypertensive patients was 51.6% and among these 3.8% had SO. Furthermore, 38.7% were overweight. AO was observed in 66.1% of the whole. Both obesity and AO were significantly more prevalent in women. When evaluating the patients according to categories of BMI, we observed greater levels of BP (from 145.5/84.5 to 149.5/89 mmHg, p<0.0001), worse control over BP (from 29.6% to 15.4%, p<0.0001) and a greater prevalence of MetS (from 20.8% to 66.9%, p<0.0001) as weight increased. Likewise, an increase in both BMI and AO was associated with worse control of BP (obesity, OR = 1.343 (95% confidence interval, CI, 1.251-1.442); AO, OR = 1.292 (95% CI 1.201-1.389).

There is a high prevalence in Spain of obesity and AO in patients with hypertension. These conditions are associated with metabolic alterations and worse BP control.