The benefits of treating patients with mildly elevated blood pressure who are free of cardiovascular disease are unclear, according to a Cochrane review. These findings conflict with current hypertension treatment guidelines in the U.S., Canada, and Europe.
Researchers analyzed data from nearly 9000 participants in four trials and found no obvious benefit of drug treatment in patients with mild hypertension (systolic BP, 140 to 159 mm Hg and/or diastolic BP, 90 to 99 mm Hg) in terms of total mortality or cardiovascular events at 5 years' follow-up. They did, however, see an increased likelihood of drug withdrawal due to adverse effects (relative risk, 4..
Individuals with mildly elevated blood pressures, but no previous cardiovascular events, make up the majority of those considered for and receiving antihypertensive therapy. The decision to treat this population has important consequences for both the patients (e.g. adverse drug effects, lifetime of drug therapy, cost of treatment, etc.) and any third party payer (e.g. high cost of drugs, physician services, laboratory tests, etc.). In this review, existing evidence comparing the health outcomes between treated and untreated individuals are summarized. Available data from the limited number of available trials and participants showed no difference between treated and untreated individuals in heart attack, stroke, and death. About 9% of patients treated with drugs discontinued treatment due to adverse effects. Therefore, the benefits and harms of antihypertensive drug therapy in this population need to be investigated by further research.
Vancouver, BC - A review of close to 9000 patients in four randomized controlled trials comparing pharmacotherapy and placebo for primary prevention of cardiovascular events in mild hypertension found no benefit with treatment [1]. But the study, published online August 15, 2012 in the Cochrane Database of Systematic Reviews by Dr Diana Diao (University of British Columbia, Vancouver) and colleagues, had too few events to be able to draw any concrete conclusions, outside experts caution.
Diao et al say the outcomes of pharmacotherapy in this patient subgroup have not been previously rigorously studied. With this analysis, "[using] the best available evidence . . . we have a clear answer that we do not know that the benefits of treatment outweigh the harms for this population," senior author Dr James M Wright (University of British Columbia) told heartwire in an email.
However, two outside experts speaking to heartwire voiced major concerns about this review.
"The most important problem in this analysis is that it's just simply too small—it has too few events and it's grossly underpowered to make any kind of statement," said American Society of Hypertension president Dr William B White (University of Connecticut, Farmington). "I think that the entire conclusion of this analysis is flawed. It really has no clinical importance, [and] it should not be adopted by any practicing physician."
Dr Suzanne Oparil (University of Alabama, Birmingham) echoed these statements, saying, "I don't think the paper is particularly important, because it's looking at a very small number of participants . . . followed for only four to five years . . . [and] because of the very small number of events."