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Showing posts from January, 2014

pre-operative testing

agency for healthcare research and quality (AHRQ) just came out with their synthesis of the data on routine preoperative testing (see link:  http://effectivehealthcare.ahrq.gov/search-for-guides-reviews-and-reports/?pageaction=displayproduct&productID=1846  ).  assessed literature on kids and adults of routine testing vs no testing or ad hoc testing, and routine vs per-protocol testing (per-protocol testing is testing a subset, eg EKG for those > 50yo, or hct in premenopausal women).  57 studies reviewed (14 comparative and 43 cohort). results: good  news:  data for cataract surgery is the best: routine pre-op testing (EKG, metabolic panel or glucose, cbc) has no effect on total perioperative complications. bad  news:  insufficient evidence for all other procedures and insufficient evidence comparing routine and per-protocol testing. no evidence regarding quality of life or satisfaction, resource utilization, or harms of testing.  and, results of cataract surgery pre-op

testosterone and MI

there seems to be much more demand for testosterone (i assume promoted by advertising and men's magazines), even in inner city Boston.  there have been a couple of cautionary articles in the past year or so (small RCT in 2010 of testosterone gel in men with  decreased muscle function, stopped because of excess cardiovasc events; VA study of men>60yo most with CAD found increase in cardiovasc outcomes).  the open access journal PLOS ONE published an article today funded by the national cancer institute -- and not pharma  (see  testosterone and nonfatal MI pLos 2014 , or  DOI: 10.1371/journal.pone.0085805), a cohort study of 56K men prescribed testosterone therapy (TT) from a large health-care database (representing men from around the US) and looked at the incidence of MI in the 90 days following the initial prescription (earlier studies found excess cardiovasc risk occurred soon after starting TT). they compared this rate to  167K men  men receiving phosphodiesterage-5 inhibito

CT and radiation

i realize that i have spent a disproportionate amount of time writing about the risks of CT scan (and xray exposure in general). but there was a really good editorial in the NY times today by a cardiologist and radiologist (see  http://www.nytimes.com/2014/01/31/opinion/we-are-giving-ourselves-cancer.html?ref=todayspaper ). their points: --cancer deaths are increasing relatively, as heart disease (the major killer) mortality has decreased over the decades --medical radiation exposure has increased 6-fold from 1980s to 2006 --one in 10 americans get a CT scan every year (and many more than 1/yr), with radiation 100 to 1000 times higher than regular xray --british study of kids exposed to multiple CTs found 3x incidence of leukemia and brain cancer --? role of direct-to-consumer advertising or financial incentives of MDs.  though i would add here that xrays have become part of the "culture" and patient expectations: patients often come to me requesting an xray/CT etc

artificial sweeteners

the boston globe today had an interesting article on artificial sweeteners (see  http://www.bostonglobe.com/lifestyle/health-wellness/2014/01/27/are-calorie-sweeteners-safe/B56kqUuKVJwcEfcWx2PmhO/story.html?s_campaign=email_BG_TodaysHeadline ). deborah kotz quotes some studies and interviews several people (including walt willett at harvard school of public health, who does lots of nutrition studies). their points: --more than 12% of children now drink artificially-sweetened beverages (twice the rate of 15 yrs ago) --manufacturers have changed: in 2007 16 of them agreed to decrease calories to stem the obesity epidemic -- by 2012  selling 6.4 trillion fewer calories but,... --johns hopkins study: dietary surveys of 12K americans found that overweight people drinking diet beverages (vs sugar-sweetened ones) consumed 88 more cal/day. obese americans consumed 194 additional calories.  ?? if these drinks using extremely sweet but artificial sweeteners (200-600x sweeter than su

mammography concerns update

i sent this out in december, but wanted to update the 3rd item below by H Gilbert  Welch  (the NY times editorial) by giving the formal article/citation which appeared in Dec 30th issue of JAMA Internal Medicine (see  mammog benefits harms jama int med 2013 , or  doi:10.1001/jamainternmed. 2013.13635)  , with a presentation/quantification of the benefits (avoiding advanced breast cancer and cancer deaths) and the harms (false alarms, overdiagnosis, and unnecessary treatment). the following is the conclusion of their mathematical modeling, using low and high estimates from the actual studies, expressed as per 1000 women screened annually for 10 years in women initially aged 40, 50, or 60. 40 yo women:     benefits -- 0.1-1.6 women will avoid dying from breast cancer;                            harms -- 510-690 women will have at last 1 "false alarm" with 60-80 getting a biopsy;                              ?? -11 women will be overdiagnosed and treated needlessly with

heart devices -- with an accessory pathway

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these 2 headlines came across my desk today.  related?? turns out that medical devices much less regulated than drugs.  Geoff Big Changes to Heart Devices OK’d Without New Data      Many of the high-risk implantable cardiac devices in use today were approved through a supplement pathway that does not require new clinical data on the safety and effectiveness of changes made to the products since their original approval, a review of an agency database showed.   Read more Dangerous Rapid Calcification Observed in Pediatric Patients After Aortic Valve Replacement By Larry Husten Pediatric cardiac surgeons at Boston Children's Hospital are warning about a potentially fatal problem in children and young adults who received a bioprosthetic cardiac valve. The surgeons initially became concerned when a young, asymptomatic patient died suddenly after her valve underwent rapid calcification, only 7 months after a routine follow-up echocardiogram found no signs of blockage.

vitamin d:multiple sclerosis and dosing in infants

several articles have come out over the past few months on vitamin d. there are a slew of them sent out over the past couple of years in the dropbox, including review articles (eg  vit d review nejm 2007 , or N Engl J Med 2007;357:266-81) highlighting the vast array of possible important actions of vitamin D in immune function, cancer prevention, heart disease prevention, as well as the better documented effects in bone health and preventing falls in elderly. last year there was an article finding that obese adolescents with low vitamin D had improved insulin sensitivity on repleting vitamin D levels (see  vit d and insulin sens adol am j clin nutr 2013  in dropbox, or doi: 10.3945/ajcn.112.050013). here are 3 more articles with more mixed results. 1. large meta-analysis of vitamin d supplementation and bone mineral density/BMD (see  vit d and bmd review lancet 2014  in dropbox, or doi.org/10.1016/S0140-6736(13)61647-5). included 23 studies (mean duration 2 yrs, 4082 people, 92

adiponectin and diabetes

a new article appeared in Nature which may be an important breakthrough in diabetes care/prevention in the future, targeting probably the primary pathophysiologic disturbance in the development of type 2 diabetes (see  dm adiponectin analog nature 2014  in dropbox, or doi:10.1038/nature12656). adiponectin has been known for years as a naturally occurring hormone produced in adipocytes, with lower levels found in obese people and those with diabetes. there is a strong relationship between lower adiponectin levels and visceral adiposity as well as the development of insulin resistance, and by increasing adiponectin levels there is improved insulin sensitivity (presumably through increasing fatty acid oxidation and inhibition of hepatic glucose production) and lowered blood glucose levels. adiponectin levels are increased by the glitizones and that may be their mechanism to improve insulin sensitivity. in addition adiponectin has anti-inflammatory and anti-atherogenic effects in several

smoking and varenicline

there were a few important articles in the jan 8th JAMA on smoking -- i will highlight 2 of them on varenicline, a partial agonist which binds with high affinity as well as specificity to neuronal acetylcholine receptors. smoking cessation in smokers is the most significant single intervention to decrease mortality, and 62% of deaths in female smokers/60% of deaths in male smokers are attributable to smoking. 1. i had sent out a general smoking cessation article about one year ago from JAMA which referenced some small study finding benefit of combining varenicline with bupropion. the current study (see smoking varenicline and buprop jama 2014 in the dropbox, or doi:10.1001/jama.2013.283185) was a 12-month multi-center RCT comparing varenicline with bupropion vs varenicline with placebo, with both medications dosed as is generally recommended.  results:     --500 patients (mean age 42, 94% white, 45% women, 78% completed at least some college -- study done at Mayo clinic and univ minnes

b-blockers in COPD patients post-MI

There have been several articles over the past 1-2 decades suggesting that the vast majority of patients denied b-blockers post-MI (most of whom had COPD) clinically should have been prescribed b-blockers, albeit carefully. a recent analysis in BMJ retrospectively accessed a large UK electronic database  from 2003-8 , assessing whether COPD patients with an MI were prescribed b-blockers, and what their clinical outcome were (see  cad bblockers postMI in COPD bmj2013  or doi: 10.1136/bmj.f6650).  results: --there were 1063 patients with COPD who were hospitalized with an MI in the cohort. not surprisingly, some differences between those prescribed b-blockers and those not (those put on b-blockers were younger and less likely to have history of hypertension, PAD, heart failure, dyslipidemia, angina prior to MI). GOLD staging was similar between the groups. only 40% of patients with MI and COPD were prescribed b-blocker while in the hospital --med adherence was 80% at one year, dec

Mediterranean diet and primary prevention of CAD

The email/blog i sent out yesterday on the Mediterranean diet and diabetes prevention is a substudy of the larger PREDIMED study, and i forgot to mention that i had sent out another article on this study finding decreased development of cardiovascular disease with either of the Mediterranean diets (with extra--virgin olive oil or nuts) as compared to the low-fat diet.  this email/blog is as below.  geoff  Nejm with article on mediterranean diet in primary prevention (see  cad prevent mediterranean diet nejm 2013  in dropbox, or DOI: 10.1056/NEJMoa1200303), as follows:   --7500 spanish patients aged 55-80, 57% women, with high cardiovascular risk (type 2 dm, or at least 3 risk factors of smoking, htn, inc LDL, low HDL, overwt/obese, or fam hx premature cad) but no evident cardiac disease. Other baseline characteristics: 40% on statins, 20% on antiplatelet rx, 50% on ACE-i. pts assessed for primary outcome of major cardiovasc event rate (MI, stroke, of death from cardiovasc ca

the many functions of albumin admin in cirrhosis

recent review of the role of albumin in cirrhosis (see  cirrhosis albumin therapy hepatology 2013 , or  H EPATOLOGY  2013;58:1836-1846 ) , which strays a bit from the primary care focus of the vast majority of these emails/blogs, but i always find it interesting when new data significantly changes the way we look at how the body works.  in this case, albumin therapy was always presented as a plasma volume expander, but it turns out that there are many other roles it plays (and who knows which is the most important physiologically???). basically, its biological roles (in patients with cirrhosis) include:           --plasma volume expansion (provides 75% of the plasma oncotic pressure) and is >50% of total plasma proteins         --binds to diverse array of molecules (bile acids, hormones, metals, long-chain fatty acids, nitric oxide, endotoxins....): solubilizes , transports them         --the thiol group on albumen is the most important extracellular antioxidant (80% of the