Carriers of mutations of the fibrinogen- gene also had a lower risk of stroke on lisinopril compared with amlodipine than those who were homozygous for the usual allele, potentially because ACEIs lower fibrinogen levels and this effect is more clinically important among those with mutations associated with higher The role of genetic testing in hypertension management remains undefined at present, however. Recent evidence suggests that intraindividual variability in BP may confer risk beyond that caused by mean elevations in BP alone.252 There is further observational evidence that calcium channel blockers may have benefits in reducing BP variability that are not present with -blockers and that these benefits may provide additional benefits in stroke risk reduc- Twenty-four hour ambulatory BP monitoring pro- vides additional insight into risk of stroke and cardiovascular events. Measurements of nocturnal BP changes ( reverse dip- ping or extreme dipping ) and the ratio of nocturnal to day- time BPs may provide data about risk beyond that provided Further study of the benefits on stroke risk reduction of treatments focused on reducing intra- individual variability in BP and nocturnal BP changes seem warranted. Controlling isolated systolic hypertension (SBP 160 mmHg and DBP <90 mmHg) in the elderly is also impor- tant. 