{"id":1007,"date":"2016-03-24T15:32:05","date_gmt":"2016-03-24T15:32:05","guid":{"rendered":"http:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/?p=1007"},"modified":"2017-08-21T11:03:35","modified_gmt":"2017-08-21T11:03:35","slug":"primary-care-corner-with-geoffrey-modest-md-atrial-fibrillation-and-lower-bp","status":"publish","type":"post","link":"https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/2016\/03\/24\/primary-care-corner-with-geoffrey-modest-md-atrial-fibrillation-and-lower-bp\/","title":{"rendered":"Primary Care Corner with Geoffrey Modest MD: Atrial Fibrillation and Lower BP"},"content":{"rendered":"<p><strong>By Dr. Geoffrey Modest<\/strong><\/p>\n<p>Although there have been many\u00a0studies confirming a role of hypertension in the development of atrial fibrillation (AF), a secondary analysis of\u00a0the\u00a0LIFE trial gives insight into the effects of achieving different levels of blood pressure on\u00a0the\u00a0frequency of development of AF (see\u00a0Hypertension. 2015;66:368). The LIFE trial (Lancet. 2002;359:99)\u00a0used 2 different hypertensive agents (losartan and atenolol) in patients with EKG-documented LVH\u00a0to assess differences in clinical outcomes.<\/p>\n<p>Details:<\/p>\n<ul>\n<li>8831 hypertensive patients (mean age 66.6, 45% male,\u00a06% Black race, 13% with diabetes, 18% ischemic heart disease, 7% MI, 5% stroke, 15% smokers, BMI 28), with EKG LVH and no history of AF, in sinus rhythm on baseline EKG, were randomly assigned to losartan or atenolol, and followed 4.6 years<\/li>\n<li>Patients with\u00a0in-treatment\u00a0achieved SBP \u2264\u00a0130 mmHg (lowest quintile at last measurement in the study) were compared to those with SBP 131-141 vs those with \u2265\u200b142<\/li>\n<\/ul>\n<p>Results:<\/p>\n<ul>\n<li>New onset AF developed in 701 patients (7.9%)<\/li>\n<li>In multivariate analyses (controlling for age, sex, race, DM, history ischemic heart disease\/MI\/heart failure, serum glucose\/creatinine\/microalbumin, prior BP therapy), comparing achieved SBP of \u2265\u200b142 mmmHg:\n<ul>\n<li>Achieved SBP of \u2264\u200b130\u00a0mmHg was associated with a 40% lower risk of AF (18-55%, p=0.001)<\/li>\n<li>Achieved\u00a0SBP of 131-141 mmHg\u00a0was associated with a 24% lower risk of AF (7-38%, \u00a0p=0.007)<\/li>\n<\/ul>\n<\/li>\n<li>\u200bFor each 10mmHg decrease in SBP: \u00a013% lower risk of\u00a0AF (9-17%, p&lt;0.001)<\/li>\n<li>\u200bAnd, no difference in benefit of lower\u00a0SBPand AF in those &gt; or &lt;60yo<\/li>\n<li>But, lowering SBP to \u2264125 mmHg was no longer associated with reduced risk of\u00a0AF (all achieved SBPs less than 125 were nonsignificantly related to the development of AF, though the hazards ratio trended to increasing risk with progressively lower SBP)<\/li>\n<\/ul>\n<p>So, a few points:<\/p>\n<ul>\n<li>Although the LIFE cohort included only patients with LVH on EKG, it has the advantage of using 2 different BP meds with 2 different mechanisms of actions. This makes it more likely that it is the achieved blood pressure which correlated with the development of AF. (With only one medication, one might wonder if the association\u00a0was the blood pressure lowering effect or perhaps\u00a0some other unrelated effect of the med).<\/li>\n<li>But,\u00a0one concern here is that those on losartan had somewhat lower likelihood of developing AF (in those who developed AF,\u00a046.2% were\u00a0on losartan\u00a0vs 50.6% on atenolol). And we know from the LIFE study that those on losartan had more regression of their LVH than those on atenolol,\u00a0and this\u00a0was the purported reason that in the overall LIFE trial there were overall fewer cardiac events in the losartan group. In fact, the incidence of cardiac events in the LIFE study overall\u00a0was equivalently\u00a0lower in both the losartan and atenolol groups when there was regression of LVH, but regression\u00a0was more common in the losartan group. So, it may be that looking at the\u00a0post-hoc analysis\u00a0of hypertensive patients with LVH and their likelihood of developing AF might\u00a0not be\u00a0so\u00a0generalizable to\u00a0hypertensives without LVH (.e., if the development of AF\u00a0were at least partly\u00a0related to LVH on EKG).<\/li>\n<li>Prior articles have had somewhat mixed results: the Cardio-Sis trial (Lancet. 2009;374:525) found statistically fewer cases of new onset AF in those on tighter control (achieved SBP of 131.9 mmHg\u00a0was better than 135.6), though another study did not (Am J Hypertens. 2008;21:1111)<\/li>\n<li>So,\u00a0this trial adds to the argument that more dramatic lowering of the blood pressure may have another positive effect: decreasing the likelihood of developing AF. And, of course, this is a really important clinical endpoint (stroke, other emboli, risks of prolonged anticoagulation and\/or cardiac procedures, risk of sudden cardiac\u00a0death and\u00a0heart failure,\u00a0risk of cognitive decline, &#8230;). though there were also limitations of the SPRINT trial (see\u00a0<a href=\"https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/2015\/11\/19\/primary-care-corner-with-geoffrey-modest-md-tighter-blood-pressure-control-the-sprint-trial\/\">https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/2015\/11\/19\/primary-care-corner-with-geoffrey-modest-md-tighter-blood-pressure-control-the-sprint-trial\/<\/a>\u200b , which did not include diabetics but did find a pretty much\u00a0all-endpoint benefit of tighter control at\u00a0an achieved SBP of 121\u00a0mmHg), this current\u00a0study does add to the literature suggesting more aggressive goals of therapy,\u00a0with\u00a0SBP target in the 125-130 mmHg range,\u00a0at least in those with EKG-LVH. Though, it should be added, that this study had too few diabetics to make a meaningful argument about their blood pressure goal, and another recent blog (see\u00a0<a href=\"https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/2016\/03\/07\/primary-care-corner-with-geoffrey-modest-md-hypertension-goal-in-diabetes\/\">https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/2016\/03\/07\/primary-care-corner-with-geoffrey-modest-md-hypertension-goal-in-diabetes\/<\/a> ) assessed a systematic review finding that the goal for diabetics should perhaps be higher than others, with a target of 140\/75-80. And I will add my usual caveat to be less aggressive with elderly, since postural hypotension\/risk of falls\u00a0is so common(?autonomic dysfunction, see\u00a0<a href=\"https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/2014\/12\/18\/primary-care-corner-with-geoffrey-modest-md-orthostatic-hypotension\/\">https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/2014\/12\/18\/primary-care-corner-with-geoffrey-modest-md-orthostatic-hypotension\/<\/a>) and too low a blood pressure can be associated with cognitive decline (see\u00a0<a href=\"https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/2015\/04\/23\/primary-care-corner-with-geoffrey-modest-md-too-low-blood-pressure-and-cognitive-decline-in-elderly\/\">https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/2015\/04\/23\/primary-care-corner-with-geoffrey-modest-md-too-low-blood-pressure-and-cognitive-decline-in-elderly\/<\/a>\u00a0).<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Primary Care Corner with Geoffrey Modest MD: Atrial Fibrillation and Lower BP  [&#8230;]<\/p>\n<p><a class=\"btn btn-secondary understrap-read-more-link\" href=\"https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/2016\/03\/24\/primary-care-corner-with-geoffrey-modest-md-atrial-fibrillation-and-lower-bp\/\">Read More&#8230;<\/a><\/p>\n","protected":false},"author":148,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[14283],"tags":[],"class_list":["post-1007","post","type-post","status-publish","format-standard","hentry","category-archive"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/wp-json\/wp\/v2\/posts\/1007","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/wp-json\/wp\/v2\/users\/148"}],"replies":[{"embeddable":true,"href":"https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/wp-json\/wp\/v2\/comments?post=1007"}],"version-history":[{"count":0,"href":"https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/wp-json\/wp\/v2\/posts\/1007\/revisions"}],"wp:attachment":[{"href":"https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/wp-json\/wp\/v2\/media?parent=1007"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/wp-json\/wp\/v2\/categories?post=1007"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/stg-blogs.bmj.com\/bmjebmspotlight\/wp-json\/wp\/v2\/tags?post=1007"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}