Response to Upward Hypertension Trends: Changes in Blood Pressure or in Antihypertensive Treatment?
We thank Chiolero et al1 for raising an additional hypothesis for the increase in hypertension prevalence, and, indeed, increased treatment at lower blood pressure levels could be part of the explanation of the trend, especially in non-Hispanic men. Although there is an increase in the size of the treated population, it is impossible to know from National Health and Nutrition Examination Survey data to what extent this increase might be because of greater treatment in persons with true pressures >140 and/or 90 mm Hg or those with values below these levels. In addition, it is precisely in non-Hispanic men that rising obesity/overweight had the greatest effect on prevalence estimates in adjusted analyses. Also, if even more of the mildest hypertensive men were being removed from the nonhypertensive to the treated hypertensive category, one would expect mean systolic pressure (in addition to diastolic pressure) in both subsets to be lowered, and these decreases were not observed (Table 5 in Cutler et al2). In women mean systolic pressures actually rose overall and in the nonhypertensive category and did not fall in the treated hypertension category. Thus, if prevalence is being increased because of previous random crossing of the diagnostic threshold, there is no evidence that the systolic blood pressures in such individuals is falling again because of regression to the mean or because of treatment and control, which should be quite easy to achieve in such patients.
We believe that because systolic pressures (the most prognostically important blood pressure measure) are falling so little, and control rates among those treated are, although improved, still far from ideal, the most pressing message from our findings is the need for increased emphasis on preventive public health strategies. As the first author of our article has stated, there is “extensive evidence on lifestyle causes of rise in [blood pressure] with age and resultant high incidence of prehypertension and hypertension,” and “widespread application of existing knowledge can make the rise in [blood pressure]with age rare and optimal [blood pressure] levels common in all population subgroups.”3
Chiolero A, Paccaud F, Bovet P. Upward hypertension trends: changes in blood pressure or in antihypertensive treatment? Hypertension. 2009; 53: e22.
Cutler JA, Sorlie PD, Wolz M, Thom T, Fields LE, Roccella EJ. Trends in hypertension prevalence, awareness, treatment, and control rates in United States adults between 1988–1994 and 1999–2004. Hypertension. 2008; 52: 818–827.
Cutler JA, Stamler J. Chapter B98. Prevention of hypertension. In: Izzo JL Jr, Sica DA, Black HR, eds. Hypertension Primer: The Essentials of High Blood Pressure: Basic Science, Population Science, and Clinical Management. 4th ed. Dallas TX: Council on High Blood Pressure Research, American Heart Association; 2008.