Response to Blood Pressure and Disability: First Steps in Future Studies
We thank Robbins et al1 for their interest in our work and for providing their data that support the association of systolic blood pressure with physical function and disabilities.
Better self-report functional measures, reported in our article,2 as well as physical performance measures, reported by Robbins et al,1 predict independence and vitality with aging.3,4 Both are negatively impacted by higher systolic blood pressure, suggesting that systolic blood pressure has a significant and potent effect on critical aspects of aging, such as physical robustness and functional independence. We agree with Robbins et al1 that future studies need to include both self-reported measures and objective performance measures of functional abilities. They may reflect different stages in the path from hypertension to disability. In addition, the data by Robbins et al1 further support the need to investigate the impact of lowering blood pressure on these measures in future hypertension clinical trials.
Finally, as in our study, Robbins et al1 found a differential effect of systolic blood pressure over diastolic blood pressure. This phenomenon is not surprising, because in the elderly population, systolic blood pressure is more likely to predict both cardiovascular and cerebrovascular outcomes. Both data imply that the hypertension effect is more likely to be related to elevated systolic rather than diastolic blood pressure.
Sources of Funding
I.H. was supported by grant K23 AG030057-01 from the National Institute on Aging, Bethesda, Md; the Society of Geriatric Cardiology Research Award; and the Hartford Center of Excellence career development award. D.L. was supported by grant IR01HL072377 from the National Institutes of Health. L.A.L. holds the Irving and Edyth S. Usen Chair in Geriatic Medicine at Hebrew SeniorLife. He was also supported by grants AG004390, AG08812, and AG005134 from the National Institute on Aging, Bethesda, Md.
D.L. is on the Speakers’ Bureau for Novartis, Bristol-Myers Squibb, Merck, and Pfizer and has received research support from Novartis. The remaining authors report no conflicts.
Robbins MA, Elias PK, Elias MF. Blood pressure and disability: first steps in future studies. Hypertension. 2008; 51: e25.
Hajjar I, Lackland DT, Cupples LA, Lipsitz LA. Association between concurrent and remote blood pressure and disability in older adults. Hypertension. 2007; 50: 1026–1032.
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