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Archive for July, 2013

Primary Care Corner with Geoffrey Modest: Medicare

30 Jul, 13 | by EBM

Editor’s note: For those of you outside the US this story will seem ridiculous…also, as after this post was written, the Boston Globe also published a front page article on how a hospital will pay a >$5 million fine for using “observation” status too little (the status that leads to patients paying more) with no mention of the issues below.  See  http://bo.st/13UYDFu 

Medicare

recent reports have shown that Medicare inflation (3.9%) is significantly below that of private insurors.  a recent article in the Boston Globe (see http://www.bostonglobe.com/opinion/2013/07/18/medicare-disguised-form-rationing/W6sF7dkTW08oGOlSekzlFI/story.html?s_campaign=email_BG_TodaysHeadline) notes a major part of the reason: cost-shifting to consumers. key points:

— editorial writer presents case of his 99yo mother admitted to hosp after fall and kept there 4 days for severe maxillofacial bruising.  Medicare reassessed care after she was already admitted for several days and decided it was “observation”, resulting in her being considered an outpatient (Medicare B), with 20% co-pay of the $20,000 physician fees. and, since the admission was effectively denied, no access to rehab facility or skilled nursing through Medicare

–this after-the-fact review is done by “recovery audit contractors”, for-profit vendors hired by Medicare and whose payment is linked to their denying claims!!!  Although their denials can be appealed, it is a long and expensive process for the hospitals or the patients.  The American Hosp Assn has a pending lawsuit against this practice

–the above system is part of George Bush (the second) approach to reducing Medicare costs using market incentives.  this same George Bush also enacted Medicare C and D. Medicare C allows commercial HMOs to skim: targeting healthy seniors and thereby reaping large profits. and Medicare D is the senior drug program, with seniors responsible for often large medicine co-pays and perhaps descending into the abyss of the “donut hole” requiring full medication payments. this was done through the for-profit drug system, an unmanageably huge array of profitable cvs/walgreen/etc/etc supporting remarkably profitable drug companies, instead of through bulk governmental drug purchasing as through the VA system, which would have saved on the order of 70% of the drug costs!!!!.   these private sector approaches to Medicare C&D cost hundreds of billions of dollars more than if done through rational public-sector solutions.  and now to decrease Medicare program costs, patients get hit with cost-shifting from Medicare to them!

and, so, yet again, our health care system [in the US]  is not the cohesive, coherent system of care that we all need.  the above, unfortunately, affects Medicare, which not only is the basic health insurer for our vulnerable elders but is also (if fixed) the potential starting point for developing an all-inclusive government-sponsored single payer system.

geoff

Primary Care Corner with Geoffrey Modest: intimate partner violence screening

29 Jul, 13 | by EBM

i have advocated for routine screening women for intimate partner violence (IPV) as part of the social history of patients.  there is another (a third study) published in the Lancet which found lack of utility (see Lancet 2013 doi:10.1016/S0140-6736(13)60052-5). in brief:

–australian study with postal screening of 20K women for “fear of a partner” in the past 12 months, with 52 different MDs. 5742 women responded. 731 positive screen. 386 enrolled

–intervention: usual care vs training MDs, alerting MDs that person screened positive for IPV, inviting women to 1 to 6  sessions of counseling for relationship and emotional issues.

–primary outcome of quality of live, safety planning and behavior, mental health at 12 months — no difference between groups.  the only secondary outcome with benefit from intervention was depressive symptoms

but …  IPV clearly affects health and should be asked if it could be part of woman’s presenting medical problem (eg, mental health issues of depression, anxiety, and some targeted medical probs such as abd or pelvic pain. also for women being treated for HIV or STIs. for antenatal services (where IPV is even more prevalent), there are some data that interventions may reduce IPV recurrences and improve maternal and infant outcomes (see also the editorial in the Lancet 2013, doi:10.1016/S0140-6736(13)60584-X).

this study is still pretty counterintuitive to me.  i understand that interventions are not so successful over the years, both for men and women. but there must be some less measurable outcomes, such as improved provider-patient relationship, improved provider-patient communication, improved provider empathy and understanding — and that these should translate into some benefit (eg the therapeutic efficacy of the doctor-patient relationship).

geoff

Primary Care Corner with Geoffrey Modest: CT scans increasing in kids and risk of cancer

19 Jul, 13 | by EBM

doi:10.1001/jamapediatrics.2013.311

The use of CT scans is increasing dramatically in kids. data collected from 7 large HMOs in the US over 10 years (2001-2011) in kids <15yo, with 4.9M child-years of observation. one advance in this study is that they collected the actual technical parameters (radiation dose) used in diverse facilities.  major findings:

— a doubling of CT scans done in kids <5yo over this 10-year spread (from 11 to 20 scans/1000 kids) and tripling in those 5-15 (from 10.5 to 25/1000 kids) — with numbers leveling off or slightly decreasing in the later years.

–large variability of radiation dose per scan at different sites. highest dosages overall with abd/pelvic CTs  (40% done for pain, 11% for r/o appendicitis, 6% for infection)

–Head CT was the most commonly done CT and increased 50%, though the % increase was highest in abd CT  for children 5-14yo.

–using risk models (some based on the Japanese atomic bomb survivors, with those numbers of cancers being similar in a recent CT study), they calculated that:

–in kids under 5yo, those getting head scans (the most common) assoc with one solid cancer developing per 570 CTs in girls and 1350 CTs in boys, and one case of leukemia in 5000 scans (less in older kids);

–for abd/pelvic CT: 300 scans in girls and 670 scans in boys assoc with likely development of one solid tumor (not much difference by age)

so, not huge increased risk for an individual getting a scan (ie, get one if really necessary), but in population overall, the annual pedi CT scan rate of about 4-9 million CTs/year leads to a large projected increase in cancer, on the order of 5000 cancers/yr.  some studies suggest that 1/3 of CT scans in kids are unnecessary, though changing this is sometimes difficult (we recently had a kid where we suggested doing an ultrasound as initial w/u for possible appendicitis, but the ER/surgeon insisted on CT scan). also, the great variability in radiation dosage per test (which seems in part due to radiology techs not scaling down radiation exposure sufficiently in kids) needs to be reduced.  the potential reduction in cancer by eliminating the unnecessary CTs and decreasing the radiation dosage per CT could decrease the cancer rate by more than 60%. behavior change for us guys ain’t easy, but the good news is that after repeated battering, we are really doing better at not prescribing antibiotics for likely viral bronchitis, etc

for related articles on radiation exposure and cancer  see recent posts below.  these are some of several articles over the past several years cautioning about the significant carcinogenic effects of ionizing radiation exposure, and reinforcing the Choosing Wisely recommendations of the Am Board of Internal Medicine (see also below) 

geoff

 

Primary Care Corner with Geoffrey Modest: Diagnostic Radiation Exposure

19 Jul, 13 | by EBM

JAMA. 2012;307(22):2400-2409

as many of you know from being exposed to my rantings, i am very concerned about excessive iatrogenic radiation exposure. (i believe exposure to my rantings are less toxic than the radiation).

article in jama looks at 6 integrated health care delivery systems with 1-2 million people over 15 years. effective doubling of radiation exposure in this period , esp with CT scans (increased 3-fold). calculated anticipated 2% increased risk of cancer from this increased exposure (this may be an argument to dissuade some patients who seek a CT scan unnecessarily).

geoff

Primary Care Corner with Geoffrey Modest: Choosing (Tests) Wisely…

19 Jul, 13 | by EBM

http://www.choosingwisely.org/doctor-patient-lists/

Choosing-wisely came out with long list of suggestions (this is the group who came out with the radiology suggestions last year). These suggestions come from many different specialty societies, each giving their top 5. Basically these are general guidelines to decrease testing overall and do not mean that these tests are not appropriate for certain individuals.  I will summarize some of the most relevant suggestions below. There are some minor differences between the different societies.

— avoid doing indiscriminate battery of IgE testing for allergies.  Should do targeted and specific testing only.

— no sinus CT or antibiotics for uncomplicated rhinosinusitis.

— no extensive workup for chronic urticaria (e.g. allergy testing) unless there is a clear history pointing to a specific allergy

— they suggest routine spirometry for asthma, as recommended by the various asthma/pulm societies, to make sure the diagnosis is correct.

— no DEXA scans in women less than 65 and men less than 70 as a routine screen.

— no annual EKGs and asymptomatic patients

— Pap smear as per the routine that I sent out before, including stopping at age 65 unless the patient is high risk

— no carotid artery screening if the patient is asymptomatic.

— no feeding tubes in patients with advanced dementia

— do not delay palliative care even if the patient is getting a disease-directed treatment

— no carotid artery evaluation if the patient has simple syncope and a normal neurologic exam

— avoid opiates and barbiturates for migraine except as a last resort

— preop evaluation for eye surgery should be targeted. Eg, EKG the patient has heart disease, fingerstick if patient has diabetes, potassium if the patient is on a diuretic

— not give topical antibiotics for viral conjunctivitis

— did not do a head CT in kids with minor head injuries and normal neurologic exams

— do not do routine abdominal CTs in kids with abdominal pain.  Low yield and radiation exposure is significant

— do not do stress cardiac imaging/advanced noninvasive imaging if the patient is without cardiac disease (though they do suggest doing an diabetics greater than age 40, patients with PAD, and patient was greater than 2% annual risk of heart disease — though I think these are too aggressive and even the American Diabetes Association has backed off from routine imaging in diabetics greater than 40)

— no need to do routine follow-up echocardiograms in patients with mild asymptomatic native valvular heart disease

— no need for routine preop chest x-rays

— in child with suspected appendicitis, do an ultrasound as the initial evaluation

— do not check Lyme serology for patients with diffuse musculoskeletal pain unless there is a known exposure and suggestive exam (i.e. it is not appropriate in general for people with just arthralgias)

— do not routinely get DEXA scans at intervals of less than every two years (though the patient reports we get often suggest getting them in one to two years)

— for GERD treatment, titrate to the lowest effective dose of the least potent medication

— do not get routine CT scans for patient with functional abdominal pain (per the ROME III criteria) unless there is a major change in symptoms

— avoid antipsychotics as a first line therapy for patients with behavior problems or psychiatric symptoms with dementia

— avoid increasing diabetic medications in patients over 65 to achieve an A1c of less than 7.5

— in areas where there is widespread vitamin D deficiency (like here), it is prudent just to give vitamins instead of testing everyone

— is unnecessary to check creatinine for patients with benign prostatic hypertrophy

— ultrasound is not a sensitive test for boys with cryptorchidism

— did not order coronary artery calcium scoring on patients with known CAD, for preop of relation for any surgery, or for screening and low risk patients except those with a family history of premature atherosclerosis

— do not use routine bronchodilators in children with bronchiolitis

— do not use routine acid suppressive therapies in infants with GERD

— do not screen for renal artery stenosis in patients who do not have resistant hypertension and have normal renal function, even if there is a history of atherosclerotic disease.

Note: These are many of the recommendations, with some supporting documentation.  Part of the rationale is a undoubtedly cost-saving, but part of it is also to minimize adverse effects of testing, including unnecessary radiation exposure.  Again, you should do what you think is right for the patient in front of you, but should not feel it is necessary to do the above tests routinely.

Geoff

Primary Care Corner with Geoffrey Modest: Lung Cancer Screening with low-dose CT–ready for prime time?

16 Jul, 13 | by EBM

Recent recommendations by the Am College of Chest Physicians to perform low-dose CT screening of smokers (see DOI: 10.1378/chest.12-2377).

these recommendations parallel the interim recommendations of the American Lung Association

Baseline: lung cancer is common and has generally poor prognosis (esp with lesions greater than stage 1), causing as many deaths as the combo of the next four cancers. one thing to keep in mind is that there are newer therapies that work better than the old ones — targeted to the specific tumor-associated genetic mutations engendered by the cancer (ie, possible that these treatments could change the risk/benefit analysis of screening in the future).  of note, the arena smoking-related morbidity is changing: tobacco companies have seen shrinking local markets (showing that sometimes after decades of obvious connection with lung cancer/persistent denial by the corporations, public health initiatives may work….); as a result,  there has been huge-scale exporting (“dumping”) of cigarettes to developing nations, with likely huge increases in tobacco-related morbidity and mortality in the near future.

Cancer prevention: attempts to prevent cancer in smokers mostly with different antioxidants or anti-inflammatories (eg b-carotene, aspirin, selenium, inhaled steroids, vitamine E, retinoids) have not panned out and are not recommended. preventing smoking initiation is the clearest prevention (though 15% of lung cancers are not smoking related. we do know, however,  from many epidemiologic studies over the decades that cancer risk geometrically increases with multiple insults, including air pollution/environmental exposures and occupational exposures in addition to smoking). for those who smoke,  smoking cessation clearly helps!, with about a 15 year lag to reducing the lung cancer risk to near non-smoker levels (unlike the heart disease risk, which decreases dramatically within 6 months of smoking cessation).

screening methods: old studies have not shown clinical benefit with either CXR of sputum cytology screening.                –low-dose CT screening (LDCT). lots of nodules identified (in 10-50% of smokers — for example, the National Lung Screening Trial Research Team (NSLT)—(see 10.1056/NEJMoa1102873) –screened 27K high risk patients with LDCT and 27K with CXR yearly for 3 years and followed another 3.5 yrs, and found 25% with positive screen on LDCT and 7% with CXR, finding 645 cases/100K person-yrs with LDCT and 572/100K person-yrs with CXR –13% more. most notably, there were 247 lung cancer deaths/100K person-yrs with LDCT and 309 lung cancer deaths/100K person-yrs with CXR, a significant 20% decrease (though not very large absolute numbers – difference of only 62 deaths/100K person-yrs…), and all-cause mortality decreased 7%. the LDCT pickup of cancer was similar each of the 3 years (suggesting that it would be useful to continue screening annually). but, very large number of false positives (>95% of positives were false ones). the vast majority of those with abnormal screens had follow-up radiologic procedures, a small  minority with invasive testing (1.2% of pts not found to have cancer had a biopsy or bronchoscopy).  BUT, given the high number of abnormal screens, the “low-dose” radiation did not remain so low. the CT delivered 1.5 mSv of radiation (vs 8 mSv for regular chest CT). because of the large number of positive LDCT who then received follow up chest CT or PET CT,  the average dose overall for the LDCT cohort was actually 8mSv. the rough calculation is that this degree of radiation exposure (mostly based on atomic bomb and some medical imaging studies) would create one cancer death per 2500 people screened.

–the recommendation:  for smokers and former smokers aged 55-74 who have smoked >30 pack-yrs and either continue smoking or have stopped within the past 15 years should be offered annual LDCT, if comprehensive care can be provided as in the NLST trial.

so, this recommendation, at this point, is by pulmonary specialist organizations, which may have some self-interest (organizationally, or by the individuals involved in crafting the recommendations) to be aggressive (eg, as with the american urology assn and PSA screening).  we may want to wait for a more neutral group (eg USPSTF, though i suspect they will follow suit, given that the NLST is a well-done study). my fundamental concern is that at the same time we are getting recommendations about expensive, intensive, high-tech screening for a largely preventable cancer (and with a significant but low difference in absolute death rates), we in the trenches are getting less and less support for programs to prevent or stop smoking (cutbacks in health educators, varying and variable insurance-based support for smoking cessation devices).  In addition, i am very concerned about the additional radiation exposure.

–i spoke with radiology at a local major hospital (in fact, one of the participants involved in designing and analyzing NLST) who said:

–not ready to do screening yet. need to develop protocols. but will be a low dose CT, probably no more than the 2mSv (as point of reference: CXR is 5-10x less than that).

geoff

Primary Care Corner with Geoffrey Modest: More on Hypertension from the past few years

16 Jul, 13 | by EBM

NICE  (National institute for health and clinical excellence, in the UK, which sends out recommendations for many clinical issues — well-researched and probably less influenced by pharmaceutical money, etc –.  These are very thoughtful guidelines with some major changes over JNC here (though rumor has it that a revised JNC is on the near horizon). A few very notable changes:–hctz should not be first line, and that in general, ccb’s be used first line in people over 55yo and in african-caribbean patients, while ace/arb’s be used in under 55yo non-african descent (use with care for women who might become pregnant, though there was an article suggesting that ACE-I not so bad in early pregnancy — ). There was a very interesting review, which argues that there are no efficacy data on low dose hctz and that high dose is dangerous (studies found inc in sudden cardiac deaths). Also much less decrease in ambulat bp monitoring on hctz low dose than on other meds — e.g. office BPs are ok with hctz (short-acting effect), but bp increases later so that 24-hour monitoring finds higher blood pressure on hctz. The advice to not use hctz applies as a single agent, not in combo with ace-i or betablocker, where hctz augments the effect of these synergistically. Chlorthalidone seems much better than hctz, as suggested in the messerli meta-analysis and supported by NICE, if one wants to use diuretic as first agent.

–should relax target BP in older (>80yo) to 150/90, on an individualized basis (I have many older patients who need target even higher than this, or they become dizzy and risk falling — either because of autonomic dysfunction leading to orthostatic hypotension, or orthostasis when they decrease their fluids some days or sweat more….)

–strong support for using ambulatory blood pressure monitoring for diagnosis of htn. Dovetails with review article , suggesting that pretty much anyone with office bp>140/90 should get one. (if severe htn, such as in the 180/110 or higher range, then treat).  Bottom line: strong literature that 30% of patients with office htn have normal ambulatory bp, several articles reinforce that cardiac endpoints correlate with ambulatory bp and not office bp. both of these last articles find no relationship between office blood pressure and cardiac events.  the refractory htn article (defining pts as higher than goal of 140/90 on 3 meds at full dose,including a diuretic) found that 40% of patients labeled as refractory are actually well-controlled as assessed by ambulat bp. Both NICE and the meta-analysis note that ambulatory bp monitoring may be difficult or unacceptible for some patients, and that home-based monitoring (and perhaps checking in the local pharmacies) may be adequate — but limited data.)

Geoff

Ed. note: (apologies that this note does not include specific article references; it was a prior post from another dissemination system)

Primary Care Corner with Geoffrey Modest: White Coat Hypertension-Very Common

16 Jul, 13 | by EBM

long-term Italian study looked at cardiovasc and total mortality in patients with sustained hypertension (HT) vs true whitecoat hypertension [true WCH — defined as high office blood pressure and normal 24-hr ambulatory blood pressure (ABPM) as well as normal home blood pressure], and partial whitecoat hypertension (partial WCH, defined as high office blood pressure  and either high ABPM or home blood pressure) — see doi: 10.1161/​HYPERTENSIONAHA.111.00690 .   a unique study by making this division of WCH, hoping to clarify the pretty mixed data on clinical outcomes of WCH in the literature. in brief:

–2051 subjects from general population near Milan, Italy followed 16 years

–risk of cardiovascular mortality increased in WCH vs normotensive (RR 2.04) and more so in those with sustained hypertension (RR 2.94). similar increased risks for total mortality

–but, when divide WCH into true vs partial (of which 42% of the WCH group were true and 58% partial), only the partial WCH had increased adjusted cardiovascular (RR 2.76) and all-cause mortality (1.58). no significant increase in those with true WCH.  also, notably, those with partial WCH and NOT on antihypertensive therapy did significantly worse than when on bp meds (ie the meds helped)

–10-year risk of developing sustained hypertension was 9.9% in initially normotensive, 35.5% in those with true WCH and 45.5% in those with partial WCH

several issues with this study.

–relatively small number of events (n=48 in the hypertensive group, 21 in total WCH and 8 in normotensives)– would have been better if they included non-fatal events.

–not great cardiac risk factor adjustment — only looked at smoking (only as dichotomous variable, so not include #cigarettes), and only included total cholesterol — measured at baseline

–defined hypertension also as dichotomous — turns out that the actual readings were lowest in those who were normotensive (office BP 117/77), and intermediate in WCH — still considered normal, but office BP was 143/90 but higher in those with partial WCH at 146/91 than those with true WCH (139/90), which could explain some of  the difference in outcomes as well as likelihood to progress to sustained hypertension

–i think it makes sense to view ABPM and home monitoring as complementary: ABPM gives lots of data over 24 hours, home-based gives a little data over longer intervals (giving insight into day-to-day variations). in this study office-based blood pressure was assessed by 3 recordings (after pt sitting 10-minutes), ABPM with recordings every 20 minutes, and home-based with 2 recordings (7am and 7pm, using validated semiautomatic device) — but it seems that it was only with 2 recordings!! which likely undercuts its utility

so, this is a really important issue. about 1/3 of pts with hypertension (esp at the lower levels) have WCH, and treating them unnecessarily may well be counterproductive (no real clinical benefit, and lots of negatives: exposure to meds, medicalization). i still think there is important benefit to risk stratify these patients with low levels of office-based hypertension by ABPM and/or home-monitoring (which can be done in the local pharmacies), and basing therapeutic decisions on that. of course, these patients should be followed carefully, since several studies over the years have shown the same as this one — WCH does put patients at higher risk of sustained hypertension.

i will post a prior writing which dealt with WCH, including the NICE guidelines which strongly support assessing non-office based blood pressures, a detailed review article (seer BMJ 2011;342:d3621 doi: 10.1136/bmj.d3621), and reference to a couple of studies which found that office-based blood pressure did not predict clinical outcomes.

Geoff

Primary Care Corner with Geoffrey Modest: Glycemic index, reward and risk

11 Jul, 13 | by EBM

as i’ve mentioned in several prior posts, there are pretty impressive data on the positive effects of a low glycemic index (GI) diet (ie one which documents the actual effect of different foods on the actual blood glucose levels). in general, high glycemic foods are associated with higher blood sugar levels and higher insulin levels in the early postprandial period, subsequently followed by low blood sugar levels (below the basal preprandial level), and associated increased hunger, food intake, and possibly weight.  also, high glycemic meals are associated with high triglycerides and lower HDL levels.  for an old but useful article, see  JAMA 2002; 287:2414-2423 for a more detailed physiologic description.   subsequent data have consistently found that low glycemic diets improve cholesterol/HDL ratios and are at least as good as low fat diets in decreasing weight (interestingly, several studies have shown that an ad lib low glycemic index diet leads to the same calorie ingestion as a restricted-calorie low fat diet — ie, as per the physiology noted above, the low fat diet, which typically is high in carbs, leads to increased appetite, so there needs to be calorie restriction to achieve the same calorie intake as with an unrestricted low glycemic index diet).  david ludwig (at boston childrens hosp and leader of their OWL weight loss clinic) is a major investigator and proponent of the glycemic index. another recent article by his group found that low fat diets tend to lower the basal metabolic state (ie, high carb foods make your body burn less fuel in a resting state), further tipping the scale in favor of a low glycemic diet.  and, now there is a recent article in am journal of clinical nutrition (see doi: 10.3945/ajcn.113.064113.) which looked at only a few subjects (12 overweight or obese men aged 18-35yo) in a crossover design and gave them high vs low GI diets, controlling for calories, macronutrients and palatability,  and looked at cerebral blood flow in MRI imaging 4 hours after the test meal, finding:

–as anticipated, the low GI meal was associated with lower blood sugar and lower serum insulin levels in the first 2-3 hours, then the high GI meal subjects had lower levels (ie, higher peaks early and lower troughs later with high GI meal), and the hunger rating was consistently higher with the high GI meal.

–MRI after the high GI meal showed higher activity in the right nucleus accumbens that then spread to other areas of the right striatum and to the olfactory area.  this area is an important reward and craving region (this area is also involved in substance abuse and dependence).

of note, prior studies have also shown more activity in this area of the brain when obese vs lean individuals viewed or consumed palatable foods.  the authors also noted lower striatal dopamine D2 receptor activity in obese vs lean individuals, suggesting that overeating may compensate for low dopaminergic activity.

another angle, which might be important in the long run, is that insulin is a powerful trophic hormone, which has several different physiologic effects, including stimulating HMG CoA reductase activity (and thereby increasing LDL cholesterol levels locally), stimulating smooth muscle proliferation, increasing plasminogen activator inhibitor levels (and therefore being prothrombotic), increasing inflammation, enhanced sympathetic activity, enhanced renal tubular sodium retention — all bad stuff for the heart (for review, see doi: 10.1161/ATVBAHA.111.241885).  there have been several epidemiologic studies (eg the Quebec Study about 10 years ago) which found that blood insulin levels are at least as predictive of heart disease as blood sugar levels, and independent of them. i think this is the reason that metformin (which improves insulin action and decreases circulating insulin levels) is really the drug of choice for diabetics (sulfonylureas and insulin do not have the same cardioprotective effect).

Geoff

 

Primary Care Corner with Geoffrey Modest: Insufficient evidence to screen for glaucoma?

11 Jul, 13 | by EBM

new US preventive service task force guidelines on screening asymptomatic individuals for glaucoma (see link: http://www.uspreventiveservicestaskforce.org/uspstf13/glaucoma/glaucomafinalrs.pdf

bottom line:

–open-angle glaucoma is common (2% of those >40yo)

–significant concerns about diagnostic criteria — turns out that many people with high intraocular pressures (IOP) do not have glaucoma on sophistocated (and expensive) testing, and some with glaucoma have normal IOP.

–data are pretty good/consistent that treating people with high IOP and early glaucoma/vision loss have improved visual outcomes with glaucoma therapy. but hard to predict which people with high IOP would progress to visual field loss

–but no compelling data (and not many studies…) finding that screening asymptomatic population is useful. and downside of treatment is real (cataracts, complications of surgery or medications)

–so, recommendation is: there are insufficient data to make a recommendation. american academy of ophthalmopathy suggests screening (as part of comprehesnive eye exam) with frequency depending on age and glaucoma risk factors (which are age, fam hx, African-American, maybe Latino). american optometric society recommends screening every 1-2 years

sounds to me like there really are not sufficient data to make a clear recommendation, given lack of conclusive data and evident (though small %) of harms.  the concern to me is that there are data in those people with high IOP and early glaucoma that treatment lowers risk of further deterioration of visual fields, that glaucoma is a slowly progressive disease (and, as such, would need very long studies to show that treating a 40 year old decreases poor vision or blindness at age 70), and that it is probably remarkably unreliable and late in the course to wait for patients to notice field defects (my experience is that patients can have pretty large defects in one eye and barely notice anything). so, to present this more broadly– this really raises the baseline issue for so much of what we do in primary care: what should clinical practice be when something makes some sense physiologically (high IOP is often bad for longterm vision, but probably not always), there are some positive intervention-type studies (treating those with high IOP and glaucoma/visual field defects decreases further visual field defects), the adverse effects of treatment are real but small, however there are no clear rigorous data to support an aggressive program of screening??? on this issue i tend to support the screening (since preventing loss of vision in older people is so important to their quality and quantity of life), though when i teach residents i will more clearly enunciate the lack of clear-cut data.

geoff

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