Passive Smoking Tied to Masked Hypertension

From Reuters Health Information

NEW YORK (Reuters Health) Aug 20 - Ambulatory blood pressure testing suggests that people with passive domestic or work exposure to tobacco smoke are at increased risk of masked hypertension, Greek researchers report in the August issue of the American Journal of Hypertension.

"Our findings," investigator Dr. Costas Thomopoulos told Reuters Health, "demonstrate that passive smoking may be a 'hidden partner' of out-of-clinic hypertension and especially of masked hypertension."

Dr. Thomopoulos of Elena Venizelou Hospital, Athens, and colleagues came to this conclusion after studying 154 patients with regular passive smoke exposure and another 100 without exposure. All were self-referred to the hospital's outpatient hypertensive unit for blood pressure evaluation.

The subjects had blood pressure measures taken on 3 separate visits to the clinic and also underwent 24-hour ambulatory monitoring on a work day.

Compared to those who were not exposed, the passive smokers showed higher 24 hour systolic BP (126 versus 122 mm/Hg), diastolic BP (89 versus 84 mm/Hg) and clinic heart rate (79 versus 73 beats per minute) (p<0.05 for all). In addition, passive smokers had a higher prevalence of masked hypertension (23% versus 8%; p<0.01).

On multivariate analysis, passive smoking was an independent predictor of masked hypertension, as were weekly duration and intensity of passive smoke exposure, younger age, clinic heart rate, low physical activity, and standing/sitting differences in diastolic BP and heart rate.

Further studies are needed, Dr. Thomopoulos said, but these findings point in "the direction of including passive smoking evaluation in (routine) clinical practice."

Am J Hypertens 2009;22:853-859.