481552311Whatever your feelings on the rapid decriminalization of marijuana nationally as well as its meteoric rise as a cash crop, a study in this week's Lancet Psychiatry raises some red flags with regard to the use of this drug by adolescents.  As Rick and I discuss on PodMed this week, we second concerns as well as recommendations made by the authors of this study that for this group of vulnerable people, strict limits should be employed to reduce long term sequelae of marijuana use.

Investigators did a meta analysis of three longitudinal studies taking place in New Zealand and Australia, together comprising several thousand subjects followed from 13 to 30 years of age. Multiple assessments were made during the study period, but for the purposes of this analysis the relevant ones included cannabis use before the age of 17 years, with categories of never, less than monthly, monthly or more, weekly or more, or daily. Developmental outcomes to the age of 30 years included attainment of a high school degree, attainment of a university degree, dependence on cannabis, use of other illicit drugs, suicide attempt(s), depression, and welfare dependence.

The studies attempted to correct for a multitude of variables and confounders that may have impacted marijuana use and outcomes.  Here's what the paper states, "We included 53 covariate factors from the three studies in the analysis. These covariates spanned individual background and functioning, and measures of parental and peer factors... After adjustment, the associations for depression and welfare dependence were both non-significant and negligible in size. For all other outcomes the associations remained significant. The estimates for adjusted ORs [odds ratios] suggested that individuals who were daily users before age 17 years had odds of high-school completion and degree attainment that were 63% and 62% lower, respectively, than those who had never used cannabis; furthermore, daily users had odds of later cannabis dependence that were 18 times higher, odds of use of other illicit drugs that were eight times higher, and odds of suicide attempt that were seven times higher. Wow.  No matter how you spin that data, it's pretty powerful.  Moreover, the analysis identified a clear dose-response between deleterious outcomes and frequency of marijuana use.

What is it that makes marijuana use especially problematic for adolescents?  Evidence has been abundant for some time that adolescents undergo a period of neuronal sprouting and subsequent pruning that may account for their oft-observed impulsive behavior, and that seems to give way to a greater degree of sense as individuals age into their twenties and beyond. Perhaps the presence of metabolites of cannibis in the central nervous system hinders this process somehow.  Another explanation is that there is already some proclivity among those prone to choose cannibis use that accounts for the apparent sequelae.  In any case here's what we know:  there won't be a prospective trial anytime soon enrolling lots of teenagers and randomizing them to various frequencies of cannabis use or not, then looking at outcomes.  For now, we agree with the authors of the paper that both efforts to limit the availability of marijuana to teenagers as well as screening efforts should be employed, as we are all vested in the outcome.

Other topics this week include new hip and knee prostheses in BMJ, questionable medication use in people with profound dementia in JAMA Internal Medicine, and aspirin to prevent preeclampsia in Annals of Internal Medicine.  Until next week, y'all live well.

 

 

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492027539ZMapp is the name of a treatment that's been tested in our close cousins, monkeys, that's offering the only hope so far that we may be able to make some headway against Ebola virus (EBOV) infection, Rick and I discuss on PodMed this week. And while we almost never feature studies limited to non-human primates, or things published in Nature, in this case the public health import is so great we've made an exception. Thank you, monkeys!

Previous research on treatments for Ebola virus infection identified two combinations of monoclonal antibodies that looked promising:  the monoclonal antibody cocktail MB-003, consisting of human or human–mouse chimeric antibodies, and ZMAb, consisting of mouse antibodies. When these were administered after Ebola virus infection more than 24 hours previously, they still demonstrated substantial benefit. The current paper aimed to optimize the combination of these two cocktails and determine what the authors call the "therapeutic limit."

The mouse antibodies were humanized, multiple combinations of antibodies were screened in guinea pigs and Rhesus monkeys, with the animals challenged with the virus and survival noted. The optimal combination was administered to monkeys up to five days post-infection with the Guinean variant of the virus, the one currently in circulation in Africa. Eleven of twelve monkeys had both fever and detectable virus in their blood, indicating that the antibody cocktail was therapeutic rather than prophylactic. ZMapp was able to reverse severe EBOV disease as indicated by elevated liver enzymes, mucosal haemorrhages and rash in a few animals.

This is of course, the self-same cocktail of antibodies that was administered to two American workers who were infected and became quite ill with EBOV, both of whom survived. The authors note that such antibody cocktails, (and I bow here to colleagues who've vociferously corrected me on the use of 'cocktail,' implying as it does fun times and socializing, which couldn't be further from the truth with regard to infections associated with a high degree of mortality), are much less problematic clinically than antibody purified from convalescent humans, easier to scale up, and useful across the age spectrum.  In view of the patent fact that so far, containment efforts underway in Africa have sadly failed, with CDC and WHO folks predicting somewhere between 20,000 and 100,000 new infections before things damp down, seems the most compassionate strategy to get large-scale manufacturing underway as soon as possible. Rick predicts that ZMapp will likely have a role in the armamentarium even as a vaccine is developed, since there will always be a population in whom the vaccine fails to elicit a protective immune response. Having been to sub-Saharan Africa myself, it also seems likely that even highly publicized vaccination efforts are likely to miss quite a few people who would then remain susceptible to infection.  But thank God at least that vaccine development, as announced by the NIH this week, is also underway.

Other topics this week include two from NEJM: a novel agent in the management of congestive heart failure and the usefulness of flu vaccination in pregnant women, both HIV positive and HIV negative, and in the Lancet, beta blockers in people with congestive heart failure and atrial fibrillation.  Until next week, y'all live well.

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178897619_medWho knew that depression in teenagers was such a common problem, leading to things like self-harm, obesity, and risk-taking behavior? And that one in five adolescents experience at least one episode of major depression by age 18?  Rick and I both admit to being unaware of the magnitude of the problem on PodMed this week , and were heartened to see results of a study in JAMA showing that a collaborative care model employed in primary care practices is quite beneficial.

Investigators randomized 101 adolescents who screened positive for depression in a primary care setting to either usual care as self-referral to mental health care after receiving a letter from their primary care physician with their screening results or to a 12 month intervention employing follow-up by a master's level clinician with a special interest in depression, so-called 'depression care managers.' The depression care manager was empowered to assess the patient and provide brief cognitive behavioral therapy, medications, or both, after consultation with both the patient and the parents.

Outcomes included changes in a clinician-administered questionnaire on depressive symptoms and another on impairment at baseline and 12 months, and remission. As the paper states, "At 12 months, intervention youth were more likely than control youth to achieve depression response (67.6% vs 38.6%, OR = 3.3, 95% CI, 1.4-8.2; P = .009) and remission (50.4% vs 20.7%, OR = 3.9, 95% CI, 1.5-10.6; P = .007)."  Yikes.  These are really big intervention effects. It's worth noting that the outcomes reflect the hands on approach taken by the depression care managers.  Following their initial consult the DCMs followed up every one to two weeks, escalated interventions if the teenager wasn't responding, and changed medications if necessary, all at a cost of about $1400 per patient.

Issues of concern emerged from this study:  the majority of adolescents did not complete the screening assessment, and a large percentage of parents declined consent for their adolescent to participate.  In Rick's opinion, these outcomes underpin a persistent factor underpinning undertreatment of depression: stigma.  Parents did not want to admit that depression might be a problem for their teenager.  Juxtapose that against the fact that the study authors credit participatory parents as a major support in providing good outcomes in their intervention group, and the need for some strategy to overcome bias is apparent. Of course stigma relative to depression is not limited to an adolescent population, but couple that with black box warnings about use of certain antidepressant medications in this age group, resulting in reluctance on the part of primary care docs to even attempt to manage the condition, and things seem dire indeed.  Rick and I agree that the depression care manager model is one well worth exploring and implementing further, and perhaps expanding to other populations in whom depression is common.

Other topics this week include MERS contagiousness in household contacts in NEJM, cardiovascular events in low, middle and high income countries in the same journal, and self-management of high blood pressure in JAMA.  Until next week, y'all live well.

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79393642_sqIf you're a woman of a certain age, read that 'teenager,' you're probably almost inexpressibly tired of hearing about the benefits of exercise. Well, as Rick and I discuss on PodMed this week, we're giving you fodder for taking an opposing view with a study identifying at least one risk of exercise for adolescent girls.  At least if you're an elite athlete playing soccer, a study in JAMA Pediatrics demonstrates a real risk for concussion. Add this to the growing body of evidence on long term health consequences relative to concussion, and the necessity to develop interventions seems imminent. It's also a timely message as school is either just about to begin or has begun in much of the US, and sports-related injuries are likely to rise.

The study followed four 'elite' girls' soccer teams comprised of 351 female players from 11 to 14 years of age. The players were followed from March 2008 through May 2012, with over 92% completing the study. Almost 44,000 hours of athletic exposure for the players accumulated over that time period.

The study employed a validated injury surveillance system consisting of a once-weekly email sent to the player's parent with a web link to a survey querying the occurrence of head injury with concussive symptoms. Such symptoms included memory loss, difficulty concentrating, confusion or disorientation, dizziness, drowsiness, headache, more emotional than usual, irritability, losing consciousness, nausea, ringing in the ears, sensitivity to light or blurry vision, and sensitivity to noise, as identified by the 3rd International Conference on Concussion in Sport.

If concussive symptoms occurred the player received a phone call from study personnel, who queried the nature of the injury, whether the player continued to play after sustaining the injury, whether she was seen by a qualified health care professional, and whether a diagnosis of concussion was made.

Here's the data from the study:  "Soccer players experienced 59 concussions, 51 incident and 8 repeat. Among concussed players, 72.9% had 1 and 27.1% had 2 concussions. Mean (SD) length of symptoms was 9.4 (13.2) days (median, 4.0 days), with 11.9% lasting less than 1 day; 52.5% lasting 1 to 7 days; 11.9% lasting 8 to 14 days; 15.3% lasting 15 to 21 days; and 8.4% lasting more than 21 days. Most concussions occurred during a game (86.4%) involving contact with another person (54.3%), the ball (29.8%), or the playing surface (15.9%). Players were heading the ball (30.5%), goaltending (11.9%), chasing a loose ball (10.1%), or getting the ball from an opponent (10.1%) when concussed. Fouls were called in 15.2% of the concussions."

Hmmmm.  As Rick and I discuss in the podcast, this data seems to suggest that helmets might be a good idea for those playing soccer, just as they've been adopted in other sports where head injury is common and problematic.  I'm certain the 'cool factor' could be overcome if the rules simply mandated helmet use.  Another practice that perhaps should be examined is heading the ball, as almost a third of the concussions occurred as a result of this practice.  Finally, Rick and I agree that early and repeated concussion may represent more of a long term health problem for girls as previous research has shown that girls are more susceptible to sports-related concussion than boys.  The significant health benefits of regular physical activity are well-known; let's make it safer if we can.

Other topics this week include a new drug for multi drug resistant TB in NEJM, cancer screening in the elderly in JAMA Internal Medicine and smoking cessation post-hospitalization, in JAMA.  Until next week,y'all live well.

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185479646What with all the coverage of Ebola virus infection taking first place in news outlets, you may have missed another viral infection that's likely to be much more impactful here in the US, also originally an African import: Chikungunya.  As Rick and I discuss on PodMed this week and featured in an online first release in JAMA, the first two cases of local transmission of Chikungunya have occurred here in Florida, so it's official: Chikungunya has arrived on mainland USA.  And it's not cause for celebration.

As the report notes, since late last year the number of cases of Chikungunya has been increasing worldwide, with some 400,000 or so cases reported by the Pan American Health Organization.  The virus has been wreaking havoc in the Caribbean this summer, with tens of thousands of infections spread over much of the region. Until now, most cases in the United States have been the result of people traveling to the Caribbean islands and becoming infected there, then returning home.

Now, however, the typical pattern of infection has taken place in Florida, where an infected mosquito bites someone who is infected, then transmits that infection to the next person it bites.  The mosquito is merely the vector for the virus to pass from one person to another.  The virus has mutated such that it can now infect two species of mosquito:  Aedes aegypti and Aedes albopictus.  Aedes aegypti is the preferred and longstanding host, but acquisition of a single point mutation by the virus now allows it to be transmitted by A.albopictus as well.

So what about these mosquitos? A.aegypti makes its home in the southeastern US and parts of the southwest, while A.albopictus also forays further north to the mid-Atlantic and lower Midwest regions.  It's worth pointing out that in contrast to many of their peers, these two species of mosquito feed during daytime hours so wisdom regarding bite avoidance at twilight is sketchy at best.  In view of the fact that the infection mimics the flu except for joint pain many describe as 'excruciating' and 'disabling,' and can last as long as six months post-acutely, we all would like to avoid infection, so what should we do? Rick emphasizes that mosquito control is the best strategy, primarily by eliminating areas of standing water, such as flower pots, kiddie pools and the like.  Use of insect repellants and clothing is also helpful.  He points out to healthcare providers that Chikungunya is a reportable disease, so samples should be sent to local health authority or CDC labs for confirmation.

Good news has emerged also with release of data from a very early study on a vaccine candidate for Chikungunya reported in the Lancet.  In this small trial using a virus-like particle approach, volunteers did mount neutralizing antibodies to the virus and few side effects of vaccination.  Stay tuned.

Other topics this week include a number of studies examining the role of salt with hypertension and cardiovascular disease in NEJM, flexible sigmoidoscopy benefits in JAMA, and BMI and cancer in the Lancet.  Until next week, y'all live well.

 

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464185873Back in the day when I was dissecting cadavers, a note of warning swirled around the cadaver lab, advising students to read the tags accompanying their specimens to see if dementia was listed in causes of death.  If so, the advice was to double-glove, in order to avoid potential contagion with prions.  Yikes!  What are these unseen, subviral beasties about, that can survive an often prolonged bath in formalin and phenol and produce dementia in those unlucky enough to become infected?  On PodMed this week, Rick and I discuss one of them: Creutzfeldt Jakob disease, the subject of two very elegant studies in this week's New England Journal of Medicine, that may well result in a means to easily diagnose the condition in people.  First a bit of background, then let's look at the studies.

Prions are misfolded forms of a normal protein found inside cells known as the prion protein. Once inside a cell, in contrast to viruses that subvert cellular machinery in order to generate more copies of themselves, the prions simply replicate again and again, ultimately producing many copies of themselves that accumulate mostly in the central nervous system, although very minute amounts are seen elsewhere in the body. The cardinal clinical symptom is dementia.  It is the presence of these aforementioned very minute amounts of prion in other tissues that are exploited in these two studies: one in urine and the other in brushings of the olfactory epithelium at the top of the nasal cavity. If brought to clinical fruition these studies represent a great advantage over other diagnostic techniques such as brain biopsy (!) or post-mortem examination.

Urine was used to test for the presence of prions in a study of two groups of patients: 68 with one form of Creutzfeldt Jakob known as sporadic, and 14 with a variant form transmitted to humans from cows.  Regarding this group of people, the condition in cows is bovine spongiform encephalopathy.  Current known cases of the variant form number 228 but estimates are that as many as 30,000 people in the UK may be infected.

Samples obtained from these folks were centrifuged and the pellet utilized in something known as 'the protein misfolding cyclic amplification (PMCA) assay.'  This assay produces many copies of the prion so that it can be detected, and detect it they did, with almost 93% sensitivity and 100% specificity.

How about the olfactory epithelial brushings study?  This much more humane than biopsy of olfactory epithelium technique produced the following impressive results: [samples] "were positive in 30 of 31 patients with Creutzfeldt–Jakob disease (15 of 15 with definite sporadic Creutzfeldt–Jakob disease, 13 of 14 with probable sporadic Creutzfeldt–Jakob disease, and 2 of 2 with inherited Creutzfeldt–Jakob disease) but were negative in 43 of 43 patients without Creutzfeldt–Jakob disease, indicating a sensitivity of 97%... and specificity of 100%... for the detection of Creutzfeldt–Jakob disease."  Both studies used controls with dementia resulting from other causes as controls.

Good news, then, for detection, and very impressive technology.  Rick and I agree, however, that the likelihood that either of these methods will be widely applied to many is low. And of course then we have the problem of effective intervention, but that's another story. Other topics this week include 'immunonutrition' in JAMA  , an update on Ebola in NEJM and in CDC communications, and a lack of efficacy with brief drug interventions in JAMA .  Until next week, y'all live well.

 

 

 

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451876561-120x86Are you a runner?  I'm not, preferring instead to pound out the miles on my bike, the same as Rick, as listeners to PodMed know very well. Now comes a study in the Journal of the American College of Cardiology that may change my mind.  That's because this huge study examining all-cause and cardiovascular mortality risks in over 55,000 adults with an average followup of 15 years showed that running less than 51 minutes weekly, clocking in less than six miles, in one to two sessions each week was sufficient to rack up impressive reductions in mortality risk compared with not running.  Yay, I say.  Since so many of the clothes and shoes one wears to run are so cool, I think I'll be looking into this further.  For now, let's take a closer look at the study.

The study population is part of the Aerobics Center Longitudinal Study at the Cooper Clinic in Dallas, TX, designed to examine the relationship between physical fitness and activity and a variety of health outcomes.  Subjects may come to the study by self-referral, or via their employer or physician, and these ranged in age from 18 to 100 years, with women comprising 26% of the final group included in this analysis. Running or jogging in the previous three months was assessed with the baseline physical activity questionnaire, with distance, speed, duration and frequency data queried. The running data rendered the group into 6 subgroups, one non-runners and five based on running speed, duration, metabolic equivalents, amount and frequency. Participants who became runners or gave up running were accounted for, as was all physical activity that was not running or jogging, such as cycling, swimming, and so on, also subcategorized based on METs and corrected for in calculating the impact of running or jogging.

The study found that in those subjects 50 years of age or older, runners experienced a 29% lower mortality risk compared with non-runners. Regarding the entire cohort, "During a mean follow-up of 15 years, 3,413 all-cause and 1,217 cardiovascular deaths occurred. Approximately 24% of adults participated in running in this population. Compared with nonrunners, runners had 30% and 45% lower adjusted risks of all-cause and cardiovascular mortality, respectively, with a 3-year life expectancy benefit." Importantly, even a very modest 5-10 minutes per day of running provided benefit, compared with no running.  Seems to me that even if you loath the activity, don't want to get sweaty, are prone to shin splints or whatever else may ail you regarding running, five minutes a day is doable.  We have a well-known and much publicized problem with obesity and all the attendant conditions and diseases.  A simple and easy strategy like running five minutes a day may reduce this societal burden considerably, as well as simply help people feel better.  Running shoe shopping, anyone?

Other topics this week include the impact eating fruits and vegetables has on mortality in the BMJ, screening for teen substance abuse with computers in the waiting room in JAMA Pediatrics, and managing stable ischemic heart disease in Circulation (Rick is co-author!).  Until next week, y'all live well.

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72991367Handoffs, or to wax PC, handovers, are those circumstances where the person who's been managing a patient during a particular time period in the hospital meets with those just coming on to the unit and recites what's been done, current status, medications and so on relative to the patient's care as they end their shift. As Rick and I discuss on PodMed this week, and as published in a study in JAMA Internal Medicine, this is prime time for medical errors, some of which could seriously compromise patient care.  And as Rick laments on the podcast, this problem has been recognized for some time in academic medicine but has so far proven quite resistant to attempted remedies.  What did they do here?

Investigators tagged along on morning handover in two tertiary care academic medical centers in Toronto, Canada, on the general internal medicine service. Medical care on these services is provided during the day by a team consisting of one attending physician, one senior resident, at least two interns, and two medical students. At night an on-call trainee provides care, and this is usually a member of the daytime team but may be a trainee from another service or team.  Electronic medical records are employed in both centers but notes by both physicians and nurses occur on paper. The verbal handover process is supported by an Internet-based written sign out tool.

The researcher took notes during morning handover and in particular the occurrence of interruptions or distractions during the process. Each case was reviewed by investigators and pertinent data and notes by care providers integrated. Data from 26 observations revealed that  "The on-call trainee did not verbally hand over 40.4% (95% CI, 32.3%-48.5%) of the clinically important overnight issues and did not document a progress note for 85.8% (95% CI, 80.1%-91.6%) of these issues. Trainees documented 7.8% (95% CI, 3.4%-12.2%) of clinically important issues in the Internet-based written sign-out tool. There were 52 (36.9%; 95% CI, 28.9%-44.8%) clinically important issues that were neither handed over nor documented by the on-call trainee."

Wow.  That's a lot of important information relevant to a patient's care that wasn't revealed in the handoff, and didn't appear elsewhere either. Factors that may have contributed include the following: "Handover took place in many different locations in the hospital  and occurred in a dedicated team room only 41% of the time. Teams divided the handover process into more than 1 encounter 68% of the time (eg, handover of overnight issues occurred before and after morning teaching rounds). Teams met for a mean total of 71 (26) minutes to review new cases and hand over overnight issues. Teams spent most of their time reviewing new information on patients admitted during the previous night, with a mean of only 11 (10) minutes dedicated to handing over on-call overnight issues. During these interactions, teams experienced 6.1 (7.1) distractions per hour resulting in 2.6 (2.9) interruptions per hour."  As Rick opines in the podcast, these findings point to clear ways to redesign the process to help minimize the errors, while I assert that this is clearly a place where family or loved ones can help support the team in providing care by also reviewing the chart, medications, tests and so forth.  Seems a likely place where substantial improvements can be made.

Other topics this week include catheter-based thrombolysis for deep vein thrombosis in the same journal, morcellation and uterine fibroids in JAMA, and a new pathway identified in antiphospholipid antibody syndrome in NEJM.  Until next week, y'all live well.

 

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481422389Electronically based interventions in clinical care have thus far proven somewhat disappointing, as Rick and I have discussed on PodMed many times, but this week, we talk about a study utilizing electronic devices, telephone or Internet interface, and nurses to help people manage their chronic pain. The results, reported in JAMA, appear very encouraging.  Here's what they did:

Two hundred fifty people with chronic pain of at least three months duration were randomized to either usual care, administered by a physician, to manage their pain, or to automated symptom monitoring either by phone or Internet, weekly for one month, followed by every other month for months 2 and 3, and then monthly for months 4 through 12.  Subjects answered 23 questions to assess pain level, anxiety level, depression, the degree to which pain was disabling, whether current medications were being taken as prescribed and how well they were working, and whether a call with a nurse was needed.

The study utilized a stepped care analgesic optimization algorithm developed on a review of the literature relative to pharmacologic management of pain. 6 classes of analgesics were employed, ranging from acetaminophen and NSAIDs to opioids. Adjustments in type or dose of analgesic were determined by the nurse and prescribed by a study physician in the intervention group  if the subject requested a change, less than 30% improvement in the overall pain score was seen, or global improvement was not at least moderate. The control group was managed by their primary care physician.

All study participants had pain of musculoskeletal origin. People in the intervention group had greater improvement in their pain control and reductions in pain severity than the usual care group, and these results did not differ by age, gender, education level, race or socioeconomic status.  There was no difference between the telephone and Internet interface groups. Finally, when we cite that current favorite in the medical literature, number needed to treat, we see a very modest 4:1 ratio, indicating that 4 patients must be treated for one to improve significantly.  That's pretty good, considering the fact that we routinely advocate for treatments and interventions with much higher numbers, and that the intervention is inexpensive, and convenient for both patient and provider.

How about that other hot button issue right now, opioid use? Although one-third of all subjects were taking these medications at the start of the study, very few people in either group started opioids for the first time or increased their dose during the study period.  The authors opine that the systematic approach to pain assessment and medication use utilized in this study helps, and that the addition of other strategies such as cognitive behavioral therapy might further improve these results. Since pain is the most commonly reported symptom in the general population, getting our arms around best care practices is crucial.

Other topics this week include two on stroke in JAMA, pill changes and compliance in Annals of Internal Medicine, and niacin for the prevention of cardiovascular disease in NEJM.  Until next week, y'all live well.

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470639625Carotid artery stenosis.  Well, if there was ever a bit of medicalese this is it. So let's dissect the term, as Rick and I do on PodMed this week, so we can further dissect new recommendations of the United States Preventive Services Task Force or USPSTF published in Annals of Internal Medicine regarding the condition.

The carotid artery is the major blood vessel carrying blood to your head, including that critical structure: your brain.  You have two of these arteries that pass upward on either side of your neck and then divide into internal and external carotid arteries, where they may dive deep into the brain itself or supply the face, respectively. As you can feel on your own by placing your fingers on the side of your neck and feeling for your pulse, this is a sizable vessel with a big job.  So if/when blockages start to impede the flow of blood through the carotid, so-called 'stenosis' or narrowing, the consequences can be dire. Enter then the strategy of screening for carotid artery stenosis, employed some years ago now by simply listening, with a stethoscope, to blood roiling around in the artery.  This is underpinned by ultrasound examination of the artery, with both of these techniques having the advantage of being quick, inexpensive, noninvasive, and painless.  Sounds great, huh?  But does screening people who don't have symptoms result in less stroke, the aforementioned dire potential consequence of carotid artery stenosis? And once identified, does treating narrowing of the vessel really help reduce the risk of stroke or result in other deleterious consequences of treatment?

As Rick would say, that was the subject of this USPSTF guideline, based on examination of all the evidence relative to screening asymptomatic people, possibly treating them, and their subsequent risk for stroke on the same side of the body in which stenosis was identified? In short, the evidence argues against screening at all, in view of the chance that such screening will result in treatment and its host of potential side effects, none of them good.  To begin with, the use of ultrasound to screen in a population in whom the prevalence of the condition is low results in a very large number of false positive results. A perioperative stroke or death rate of less than 3% was seen in this analysis when carotid enarterectomy to remove plaque inside the artery was employed, but the authors state that observational trial results are much higher.  Finally, in comparison to medical therapy surgery is no longer emerging as the superior choice.  To sum then, in people without symptoms looks like screening for carotid artery stenosis isn't helpful and shouldn't be done.  For those of you considering such an examination as a gift for a loved one, why not choose a golf outing instead?

Other topics this week include infusion pumps for hard to control diabetes in the Lancet, medications for neuropathy in JAMA, and varenicline and a nicotine patch for smoking cessation in JAMA.  Until next week, y'all live well.

 

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