For systolic BP the HR nadir increased with increasing age: 115mmHg up to 70 years, 135mmHg for In ONTARGET involving 25,588 patients with athero- sclerotic disease or diabetes with organ damage, a J-shaped relationship between on-treatment systolic BP (nadir around 130 mm Hg) and all outcomes except stroke was observed in a Data from IDNT showed that a systolic BP below 120 mmHg was associated with an increased risk of cardiovascular deaths and congestive heart failure, but not myocardial infarction in hypertensive type 2 diabetics.228 Finally, in the ACCORD study, while targeting a systolic BP of o120 mm Hg rather than o140 mm Hg did not reduce cardiovascular outcomes, serious adverse events occurred in 3.3% of the lower BP group compared with 1.3% (po0.001) in the higher BP target group indicating the potential penalty paid for aggressive BP reduction.159 In CKD ND patients, there is observational evidence from two community-based longitudinal studies including 1549 subjects with CKD 3-4. In one study, a J-shaped relationship between stroke and systolic BP was observed, with lowest stroke risk in the range of systolic BP between 120 and 129 mm Hg, and higher risk above and below this.158 A cohort study of 860 US veterans (comprising mainly men) with CKD (GFR o60 and a subset with GFR o30 ml/min/ ) showed greater mortality when systolic BP was o133 mm Hg or diastolic BP o65 mm Hg, although it appeared that the association might not be causal but instead related to atherosclerotic CVD as a co-morbidity.413 In summary, with respect to a lowest BP target, most of the relevant evidence is observational, derived from retro- spective analyses, and nearly all involves non-CKD popula- tions. 