Predicting falls before they happen
Volume 9, Issue 21 | May 23, 2024
Also in This Issue
Bird flu update
Soft contacts that can evaluate your retina
Are melanomas overdiagnosed?
New and Noteworthy
Bird flu update: A new human case, ramped-up pandemic preparedness
Michigan state health officials have reported a case of H5N1 avian flu in a farm worker, marking the second case linked to the current outbreak in dairy cows.
The CDC has “asked local and state health officials . . . to maintain flu surveillance operations at peak-season levels over the summer,” instead of going into their typical “off-season mode” (STAT News).
To help streamline response to the outbreak, the USDA has relaxed some of its guidelines on how public-health labs and labs that handle wastewater samples “handle, store, and transport H5N1 bird flu samples,” (Reuters) Most of the changes either give labs more time to process samples and / or decrease the paperwork involved with handling them.
The CDC is using its Influenza Risk Assessment Tool to carry out a pandemic risk assessment of H5N1. The process involves measuring 10 different risk elements and “can take months to complete.” (CIDRAP)
A CDC survey of 55 state and territorial epidemiologists in 55 jurisdictions found that “in 33 of 50 jurisdictions (66%), public health authorities reported difficulties in monitoring A(H5N1) virus–exposed persons due to personnel shortages or lack of funding.” (JAMA)
Scientists have extracted a full H5N1 genome from milk, which suggests that “commercially purchased milk products could be used to monitor the progress of the bird flu outbreak in dairy cattle and to check for important changes in the virus over time.” (STAT News)
The WastewaterSCAN team found “significant H5 and influenza A levels” in samples from treatment plants near farms with confirmed H5N1 outbreaks. Levels were high both during the outbreaks as well as a week before the outbreaks were confirmed, indicating wastewater’s potential use as an early warning tool.
WastewaterSCAN will be testing samples from all of its sites (190, in 36 states) for H5 in the next few weeks and will publish results on their dashboard.
Commentary: The nation’s pandemic-preparedness machine is grinding into action - a bit more slowly than we’d like, but at least it’s moving. Good news is that risk to everyone except for dairy workers remains low at this time.
For a great overview of how the outbreak began (the cats were the key to the puzzle), check out this article from KFF Health News.
Falls can be deadly in elders. This diagnostic model could help predict them.
If you haven’t read Can’t We Talk About Something More Pleasant?, cartoonist Roz Chast’s depiction of the end of her parents’ lives, you should. It’s comic, poignant, and utterly brilliant. It also depicts a health issue that’s more serious for elderly folks than you might realize: falling.
According to research published this month in JBMRPlus, if a person age 66 or older fractures a hip (a common consequence of a fall), the chance of them dying sometime in the next five years goes up dramatically. (The relative survival ratio for males ages 66 - 85 was 52 - 64%; for those 86 or older it was 35%. For females ages 66 - 85 it was 70 - 79%; for those 86 or older it was 53%).
It would be good to know who’s at risk of taking a serious fall, so that clinicians can help those folks take steps to avoid one. But as of now, that risk is usually only assessed once someone has already fallen at least once.
A model developed using UK National Health Service data addresses this issue. It uses primary-care data from a patient’s electronic health record to predict their risk of hospitalization after a fall over the next 12 months. It did quite well, with a c-statistic of 0.82 when validated on data that wasn’t used to create the model (a c-statistic of 1.0 would be a perfect predictor; 0.5 would be no better than chance).
Measuring electrical impulses in the retina - comfortably
Eye diseases like glaucoma and diabetic retinopathy can mess up the electrical activity of cells in the retina. Clinicians can use electroretinography (ERG) to measure these changes as part of diagnosis and treatment monitoring. This diagnostic tool has the potential to be very useful - especially with incidence of these age-related diseases increasing worldwide - but it has a big drawback. Evaluating different parts of the retina at once requires the use of uncomfortable hard contact lenses.
A team from Japan may have solved this issue. They’ve developed an ERG system that uses gold mesh electrodes placed on the surface of off-the-shelf soft disposable contact lenses. So far it’s only been tested in animals, but the authors see a future in which these “smart” contact lenses send data to clinicians while patients go about their daily routines.
Food for Thought
Screening and diagnosing melanoma accurately
Summer unofficially starts this weekend with Memorial Day! Yay! Unfortunately, those of us who live in places with winter now have to start protecting ourselves from the negative impact of the sun. Boo.
The Big Bad of sun exposure is melanoma. But something odd seems to be going on with that disease in the US. The number of cases has grown dramatically (from 9 per 100,000 in 1975 to 24 per 100,000 in 2019), while the death rate has stayed just about the same throughout this entire 45-year period (2-3 per 100,000). Why?
Two possible explanations:
Potentially fatal cases are going up more or less in proportion with overall cases, but treatment (including tumor resection) has been very effective.
The number of potentially fatal cases isn’t increasing, but earlier diagnosis - potentially overdiagnosis - is.
A recent observational study in Evidence Based Medicine makes a strong case for the overdiagnosis option. Their data shows that the melanomas now being diagnosed are primarily in situ, also known as stage 0. Most importantly, 87.4% of them are indolent and need no further action.
Commentary: As we comment frequently, avoiding false positives in broad-based screening programs is a huge challenge. Melanoma is another case in point.
The US Preventive Services Task Force currently recommends that unless concerning signals are present, melanoma screening should be limited. The data from this report supports that view. (Of note: A new study in the Journal of the American Academy of Dermatology suggests that up to 15% of patients with melanoma have genetic susceptibility to cancer - a lot more than the 2 - 2.5% that earlier, smaller studies found. So having a relative with melanoma could count as one of those “concerning signals.”)
When concerning skin growths do appear, molecular analysis can be used to single out more aggressive cases for further treatment. In the future, another option could be a noninvasive “virtual biopsy”: a 3D reconstruction of the cells in question, based on a penetrating laser scan of the tissue.
We will be taking next week off. Let us remember and honor the memory of those who gave their lives to protect our democracy. See you on Thursday, June 6.