Hypertension Treatment and Falls: Should We be Concerned?

Deciding whether or not to intensify therapy in an elderly patient with poor blood pressure control is a common clinical dilemma in my practice. Every year in mid-May, there are two professional society meetings that I try to attend in the partial hope that they will provide me with guidance for this difficult clinical problem. Yet, when it comes to hypertension treatment and fall risk in the elderly, it seems as if the messages from these two meetings could not be further apart. At the American Society for Hypertension meeting, hypertension specialists routinely state that with all the clinical trials performed, they have never seen an excess risk of falls and fall-related injuries in older patients receiving more intensive blood pressure treatment. They will further cite the landmark Systolic Hypertension in the Elderly Program (SHEP), one of the few clinical trials to systematically examine falls, which reported no increase, despite a greater than 10 mmHg drop in systolic blood pressure in the active treatment group when compared to placebo.1 Consequently, clinicians should not refrain from treating their elderly patients to guideline-recommended thresholds because of concerns over falls. Yet, at the American Geriatrics Society meeting, geriatricians routinely caution against overtreatment with medications, with anti-hypertensives being particularly problematic in the elderly due to the risk of falls. As evidence, they cite abundant anecdotal evidence as well as results from well-performed observational studies.2 What are primary care clinicians to do? This question on whether or not to intensify anti-hypertensive therapy when patients are above recommended blood pressure goals is not a trivial issue, given the prevalence of uncontrolled hypertension and the fact that older age is associated with worse control.3 Failure to adequately control blood pressure leads to an excess risk of stroke and other cardiovascular events. Treatment, though, if associated with falls, will lead to hip fractures, functional impairment, and long-term care placement. Fear of falling, present in 25 % of community-dwelling elderly, may also be exacerbated by hypertension treatment, leading to further decrements in quality of life.4 Not surprisingly, many elderly patients will forego hypertension treatment intensification due to potential concerns with the consequences of falls-related injury.5 The hypertension specialists will derive additional support for their view from this issue of the Journal of General Internal Medicine. Margolis et al. describe results from the Action to Control Cardiovascular Risk in Diabetes (ACCORD) randomized clinical trial.6 Among a subsample of 3,099 participants with hypertension and diabetes, the incidence of falls was similar in those randomized to a target blood pressure of 120 mmHg compared to a target of 140 mmHg. Moreover, there was a trend for fewer non-spine fractures in those participants receiving more intensive therapy. This was an exceptionally well-performed study. Information on many risk factors for falls was prospectively collected and adjusted for in the analyses, including visual acuity and peripheral neuropathy. We have no reason to doubt the internal validity of these results. Yet, the geriatrician in me still has doubts, and I question whether these results are relevant to the frail elderly patients I see in my clinical practice. It has long been recognized that the elderly are under-represented in clinical trials,7 and studies performed in younger patients cannot be blindly applied to frail older patients with multiple comorbidities.8 This certainly seems to be relevant to these results from ACCORD. The mean age was 62 years and only 34 % of the sample was between 65 and the upper age limit of 80 years. Information on functional status, comorbidities, and frailty were not provided. The Hypertension in the Very Elderly Trial (HYVET), with its sample of over 3,000 patients age 80 and older, also failed to show an increased risk of fractures in patients receiving more intensive blood pressure therapy.9 However, it has been suggested that despite their age, these patients were relatively healthy. Thus, the external validity of the study reported by Margolis et al., whether it applies to the frail elderly patients we are most concerned about, remains uncertain. This uncertainty in how aggressively to treat frail elderly patients with hypertension so as to avoid falls is compounded by the recent disagreement among hypertension specialists on the target blood pressure for patients aged 60 and over. While randomized clinical trials of elderly patients have demonstrated the benefits of treating to a target blood pressure of 150 mmHg, no convincing evidence exists for further reductions to 140 mmHg. Consequently, the Eighth Joint National Committee recently recommended increasing the target systolic blood pressure from 140 to 150 mmHg in people aged 60 years and older. This recommendation was opposed by a sizable minority of Committee members,10 and highlights the uncertainty in balancing the benefits and risks of intensive blood pressure therapy. Additional evidence on the optimal target blood pressure for patients with hypertension is coming. The Systolic Blood Pressure Intervention Trial (SPRINT) is a large, randomized, controlled trial comparing two different strategies for treating systolic blood pressure; aiming for a target blood pressure of less than 140 mmHg versus less than 120 mmHg.11 Unlike ACCORD, patients with diabetes, as well as stroke, are excluded from the study. Enrollment focused on specific subgroups, including patients aged 75 or over, and patients with cardiovascular or chronic kidney disease. Participants are considerably older than ACCORD, with 28 % of the 9,361 enrollees over age 75 and the mean age among this older sample being 79.8 years. Detailed assessments of frailty will be possible, with information on functional status using the Veterans Rand Short Form-12 (VR-12)12 being regularly collected on all participants and information on gait speed being collected in an elderly subsample. Fear of falling is also being evaluated in a subsample using the Falls Efficacy Scale International.13 While fall-related injury is being determined, an important limitation of SPRINT is the lack of data on total number of falls. Nevertheless, the more detailed information on functional status in the elderly, as well as data on falls self-efficacy, should result in data complementary to the study by Margolis et al. Until these data from Sprint are available, clinicians will need to continue exercising their best judgment in managing hypertension. Based on the data by Margolis et al., they likely can feel comfortable treating their healthier elderly patients with hypertension and diabetes to guideline-recommended levels without being overly concerned about fall risk. I will continue to exercise caution with my frailer, elderly patients. Hopefully, SPRINT will provide guidance on how we should manage these patients. All too often, though, randomized clinical trials seem to provide some answers, but raise more questions.