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Is BP target <130 mmHg better than >130 mmHg? The data reported in the systematic review say that the opposite is true

Posted by adonzelli on 31 Aug 2012 at 11:08 GMT

In their interesting research, Lv et al(1) state that “this analysis suggests that BP targets at 130/80 or lower are likely to produce additional overall benefit”.
But Figure 5(1) “Effects of intensive BP lowering on the risk of major cardiovascular events in subgroups of trials” shows that the risk ratio of “intensive” BP target >130 mmHg systolic (0.826) are as a trend better than the risk ratio of the “more intensive” target <130 mmHg systolic (0.888).
Moreover, >130 mmHg systolic and/or <80 mmHg diastolic (0.886) are as a trend better than <130 mmHg systolic and/or <80 mmHg diastolic (0.928).
In addition, with less intensive regimen, severe adverse events (SAEs) as a trend are even less common. SAEs include hypotension, significantly increased at lower targets (RR 4.16), especially if the target is very strict, as it was in ACCORD(2), in which a systolic BP <120 mmHg rather than a standard one (130-139 mmHg) not only increased the SAEs attributed to antihypertensive treatment (3,3% versus 1,3%; P<0.001) without any benefit in all cause mortality (hazard ratio, 1.07; 95% CI 0.85 to 1.35), but also produced a statistically significant (albeit modest) worsening of SF36 physical component score(3) of health-related quality of life.
A look at Figure 3(1) “Effect of intensive BP lowering on risk of … cardiovascular death (b)”, shows that the neutral result exhibited (overall cardiovascular mortality Risk Ratio 1.00) is “saved” by the UKPDS-HDS trial(4), in which the target systolic BP in “intensive” treatment group was <150 mmHg (and the average achieved was 144 mmHg, while in less intensive group was 154 mmHg). If a sensitivity analysis removes this trial, the overall cardiovascular mortality will favour the less intensive regimens. This fundamental outcome would be even more in favor of a less intensive regimen if the sensitivity analysis also took away the trial ABCD (H)(5), in which the final systolic BP in the intensive arm was 133 mmHg.
Finally, should be added that, from a National Health Service perspective, or anyhow from a tax-funded Health Care System perspective, systolic BP targets <130 mmHg have very different financial implications than BP targets >130 mmHg. In fact, a target <130 mmHg systolic usually requires the combination of three drugs, at least one of which very expensive; instead, a target >130 mmHg can usually be achieved with one or two drugs, for instance a thiazide-type diuretic like chlorthalidone or indapamide and an ACE-inhibitor, all available as inexpensive generics.

Alberto Donzelli, MD, Director of Service of Education for Appropriateness and Evidence Based Medicine – Local Health Unit, ASL di Milano, Italy
Luigina Ronchi, Dr. - Service of Education for Appropriateness and EBM - ASL di Milano, and Member of Board of Movimento Consumatori Milano – Italy
Sivia Sacchi, Dr. - Service of Education for Appropriateness and EBM - ASL di Milano, Documentalist
Geltrude Consalvo, MD, Service of Education for Appropriateness and Evidence Based Medicine - ASL di Milano, Italy

1. Lv J, Neal B, Ehteshami P, Ninomiya T, Woodward M, et al. (2012) Effects of Intensive Blood Pressure Lowering on Cardiovascular and Renal Outcomes: A Systematic Review and Meta-Analysis. PLoS ONE 9:e1001293
2. Cushman WC, Evans GW, Byington RP, Goff DC, Jr., Grimm RH, Jr., et al. (2010) Effects of intensive blood-pressure control in type 2 diabetes mellitus. N Engl J Med 362: 1575–1585.
3. O’Connor PJ, Narayan KMV, Anderson R, Feeney P, Fine L, et al. (2012) Effect of Intensive Versus Standard BP Control on Depression and Health-Related Quality of Life in Type 2 Diabetes. Diabetes Care, published online May 14, 2012.
4. (1998) Tight blood pressure control and risk of macrovascular and microvascular complications in type 2 diabetes: UKPDS 38. UK Prospective Diabetes Study Group. BMJ 317: 703–713.
5. Estacio RO, Jeffers BW, Gifford N, Schrier RW. (2000) Effect of blood pressure control on diabetic microvascular complications in patients with hypertension and type 2 diabetes. Diabetes Care 23 Suppl 2: B54–64.

No competing interests declared.