A Discontinuation Trial of Antihypertensive Treatment: The Other Side of the Story

Older people remain on blood pressure agents despite being hypotensive resulting in increased mortality and hospital admission

BACKGROUND

the use of antihypertensive medication in older people in order to prevent cardiovascular events is well established. The use of such agents has been encouraged by incentive schemes in the United Kingdom including the Quality and Outcomes Framework. In addition, many guidelines recommend good blood pressure (BP) control in the elderly. However, in older people antihypertensives can cause adverse effects related to hypotension.

AIM

the aim of this study was to assess the prevalence of low BP and impact on outcomes, particularly in the presence of antihypertensive treatment, in a primary care population of older people.

DESIGN

a retrospective observational cohort study in people over the age of 70 years registered with primary care providers in Kent.

RESULTS

a total of 11,167 patients over 70 years old were analysed, 6,373 female (57%). Systolic blood pressure (SBP) was below 120 mmHg in 1,297 people (844 on antihypertensives), below 110 mmHg in 474 (313 on antihypertensives) and below 100 mmHg in 128 (89 on antihypertensives). Hypotension was independently associated with mortality, acute kidney injury and hospital admission.

CONCLUSIONS

the results demonstrate that low SBP is associated with adverse events, it is possible that the pursuit of BP control at a population level may lead to over-treatment in certain groups of patients. This may result in an increased incidence of adverse events particularly in older people.

Functional Status and Antihypertensive Therapy in Older Adults: A New Perspective on Old Data

BACKGROUND

Functional status may be useful for identifying older adults who benefit from lower blood pressure. We examined whether functional status modifies the effect of antihypertensive treatment among older adults.

METHODS

Post hoc analyses of the Systolic Hypertension in the Elderly Program (SHEP), a randomized trial of antihypertensive therapy vs. placebo (1985-1991) in 4,736 adults aged 60 years or older with isolated systolic hypertension. Outcomes were all-cause death, cardiovascular (CV) death, myocardial infarction (MI), stroke, falls, and symptoms of hypotension. The effect modifier of interest was functional status, assessed by self-reported physical ability limitation (PAL).

RESULTS

Among persons with no PAL, those receiving treatment had a lower rate of death, CV death, and MI compared with placebo (4.0, 2.9, and 4.2 per 1,000 person-years lower, respectively). In contrast, among persons with a PAL, those receiving treatment had a higher rate of death, CV death, and MI compared with placebo (8.6, 5.3, and 2.7 per 1,000 person-years higher, respectively). These patterns persisted in Cox models, although interaction terms did not reach statistical significance. Treatment remained protective for stroke regardless of functional status. The rate of falls associated with treatment differed by functional status; incidence-rate ratio = 0.81, 95% confidence interval (CI) = (0.66, 0.99), and 1.32, 95% CI = (0.87, 2.00) in participants without and with a PAL, respectively, in models adjusted for demographics and baseline blood pressure (P-value for interaction, 0.04).

CONCLUSIONS

Functional status may modify the effect of antihypertensive treatment on MI, mortality, and falls, but not stroke, in older adults. Functional status should be examined in other trial settings.