Is sympathetic activation by stressful memories linked to the occurrence of hypertension and metabolic syndrome?

I propose that memory induced stress reactions increase the resting sympathetic tone, vascular resistance, secretion of renin and contrainsulary hormones. Dementia reduces this source of chronic stress reaction, and hence reduction on sympathetic activation could explain both the reduction in blood pressure and relief from insulin resistance. This might explain how is it possible that blocking of sympathetic activity and renin-angiotensin system prolongs human life, despite importance of these mechanisms in maintaining circulatory homeostasis in all mammals.