In this week s JAMA Neurology, a group led by Dr. Rebecca Gottesman, MD PhD from the Johns Hopkins University School of Medicine (and colleagues from centers in Minnesota, North Carolina and Mississippi) studied records of 13,476 patients over a 20-year period to see if elevated mid-life blood pressure led to cognitive decline.
It is well-known that hypertension (HT), high blood pressure, is a significant cause of just about every cardiovascular ailment we know: heart attack, angina, heart failure; and it is most closely linked to strokes. While there are some data pointing to HT in older age as a risk factor for developing Alzheimer s disease, the evidence is not strong for those whose blood pressure was elevated years before the AD diagnosis was made.
These researchers collected data from an initial medical visit on 13,000-plus patients in four disparate communities; the patients were recruited from the ARIC Study (Atherosclerosis Risk in Communities), and they were all between 48 and 67 years of age at the beginning, with a baseline visit at the study s outset in 1990; they were re-evaluated at up to five subsequent visits, with the study s conclusion in 2013. Fifty-eight percent of the initial subjects completed 5 visits over a 23-year period. Blood pressures were recorded as normal, pre-hypertension (BP between 120 and 139 systolic over 80-89 diastolic) or hypertension (BP over 140/90, or the use of medication for hypertension). Cognitive evaluations were done using a well-described combination of tests.
In sum, among patients in mid-adulthood, a decline in cognitive function occurred with a fairly strong relationship to the level of blood pressure: for participants with HT, decline was 6.5 percent greater than for normotensives. Those HT patients who were taking medication had a lesser decline than those on no treatment. Among patients with pre-hypertension (sometimes called borderline HT), there was less decline in cognition: their loss of mental agility did not reach statistical significance.
ACSH s Dr. Gil Ross had this comment: In fact, while this study is valuable in terms of new learning about hypertension, it is not likely and indeed should not lead to any major change in approach to the diagnosis or treatment of HT. Why should it? We already know that HT must be sought out and treated aggressively to prevent or delay the onset of CVD, kidney disease, and other chronic diseases. To also know that such treatment may also have a beneficial impact on cognitive decline is, so to speak, icing on the cake. So sure: use any rationale necessary, docs, to keep your hypertensives under good control; it will make their lives both longer and healthier, as well as more productive.