Tom Nolan’s research reviews—31 August 2023

Pred weight

How much should you worry about the effect of weight and blood pressure if prescribing long term low dose glucocorticoids? An analysis of individual data from five randomised controlled trials looked at 1112 people with rheumatoid arthritis who were either taking prednisolone ≤7.5 mg (or equivalent) per day or a control drug. After two years of treatment, those taking prednisolone weighed only 1 kg more than those in the control groups (95% CI 0.4 to 1.8 kg; P<0.001), and there was no difference between groups in mean arterial blood pressure.

Ann Intern Med doi:10.7326/M23-0192

Dead wait

In the 18th century in the US, dissection after death was seen as a form of supra-capital punishment, and judges were allowed to add dissection to a death sentence. In the 19th century the demand for bodies created a lucrative market leading to various scandals—the body of a senator going missing and being discovered in the dissecting room at the Medical College of Ohio—and even riots. Although attitudes and laws have changed, looking at how medical schools source their cadavers continues to intrigue, with a research letter in JAMA describing a rise in the number of “unclaimed” bodies being accepted by medical schools in Texas.

Texas, with its population of nearly 30 million people, has 16 medical schools, which accept about 3000 cadavers each year for anatomy training. According to the data obtained for the study, of the 3159 cadavers accepted by 14 of its medical schools in 2021, 446 of them were donated by the state after being “unclaimed.” That’s 446 people with no next of kin to mourn them or consider what the deceased would have wanted to happen to their body after death—up from 63 in 2018.

JAMA doi:10.1001/jama.2023.15132

Proteoformication

Is the human proteoform project about to transform health care? Proteomics is the study of all the proteins that get expressed in the body (in the same way that genomics is the study of how genes are expressed). A single gene can produce hundreds of different forms of a single protein, with even a single change in protein structure (by methylating an argine, for instance) potentially making a significant difference in the protein’s shape—or proteoform. The quest to map out all 50-100 million of these proteoforms is called the human proteoform project.

Measuring the levels of thousands of protein variants linked with cardiovascular disease may help with cardiovascular risk assessment, argues a new study in JAMA. The retrospective analysis looked at whether adding protein risk scores (derived from measuring 4963 plasma protein levels) to polygenic risk scores and old fashioned clinical risk factors, could improve cardiovascular risk prediction. A modest improvement in risk prediction for first and recurrent atherosclerotic cardiovascular events was found.

JAMA doi:10.1001/jama.2023.13258

#AIpathology

A study published in Nature Medicine concludes that an AI histopathology search tool known as PLIP (pathology language–image pretraining) that learned pathology from over 200 000 tweets, has achieved “state-of-the-art performances for classifying new pathology images across four external datasets.” The open-source WebPLIP platform is available for all to use and allows users to search for histopathology images with words or images. When I had a go, the search results did seem rather like my answers to histopathology questions in my medical school exams—a bit hit and miss—but if pathology and twitter is your thing, PLIP might be a handy tool.

Nat Med doi:10.1038/s41591-023-02504-3

Levers to pull after dementia diagnosis

A diagnosis of dementia is a good time to review medication use and reduce polypharmacy, but, according to a cohort study of 266 675 Medicare beneficiaries, this doesn’t seem to be happening. The study found that overall prescribing went up after dementia diagnosis (by 0.41 medications versus −0.06 in matched controls with no dementia diagnosis), and, although prescribing of anticholinergic drugs did go down, prescriptions for medications that affect the central nervous system, such as benzodiazepines and antipsychotics, went up (absolute difference 3.44% v 0.79%).

Why this happens is summed up neatly in a linked editorial: “all too often a new prescription for an antipsychotic or benzodiazepine is issued simply because we lack another lever to pull to help patients and caregivers, or the reimbursed time to explore underlying causes and devise creative behavioural and environmental solutions.”

JAMA Intern Med doi:10.1001/jamainternmed.2023.3575, doi:10.1001/jamainternmed.2023.3584