This Week in JAMA FREE

The current staging system for chronic kidney disease is based primarily on estimated glomerular filtration rate (eGFR), and patients with lower eGFR are at higher risk of adverse clinical outcomes. Proteinuria is also a marker of chronic kidney disease and is associated with adverse outcomes, but its presence and severity have not been incorporated in the current classification system for chronic kidney disease or used to refine risk estimates of disease-associated adverse events. Hemmelgarn and colleagues hypothesized that patients with both reduced eGFR and proteinuria would be at higher risk of adverse outcomes than persons with one or neither characteristic, and they tested their hypothesis in an analysis of data from a community-based cohort study of adults in Alberta, Canada. During a median follow-up of 35 months (range, 0-59 months), the investigators found that the risks of all-cause mortality, myocardial infarction, or progression to kidney failure associated with a given level of eGFR were independently increased among persons with higher levels of proteinuria.

Abnormalities of serotonin (5-hydroxytryptamine; 5-HT) receptor binding in regions of the medulla oblongata involved in respiratory and autonomic function have been reported in cases of sudden infant death syndrome (SIDS). Whether the 5-HT receptor abnormalities are associated with decreased tissue levels of 5-HT or its key biosynthetic enzyme, tryptophan hydroxylase, is not clear. To address this question, Duncan and colleagues analyzed levels of 5-HT and tryptophan hydroxylase in medullary brainstem tissue samples obtained at autopsy from cases of SIDS and from infants who either died acutely of a known cause or were hospitalized with chronic oxygenation disorders (controls). The investigators report that compared with controls, infants who died of SIDS had significantly lower levels of medullary serotonin and tryptophan hydroxylase, which suggests that SIDS is a medullary 5-HT deficiency disorder.

Compression ultrasound can confirm or exclude deep venous thrombosis (DVT) of proximal leg veins, but its accuracy to confirm or exclude distal DVT has been questioned. Whole-leg compression ultrasound may improve initial detection of distal DVT, but the safety of using a single whole-leg compression ultrasound to exclude proximal and distal DVT is not clear. In a systematic review and meta-analysis, Johnson and colleagues Article assessed the risk of DVT among patients with suspected DVT and a negative whole-leg compression ultrasound who did not receive anticoagulant therapy. The authors found that withholding anticoagulation therapy following a single negative whole-leg compression ultrasound was associated with a low risk of venous thromboembolism during 3 months of follow-up (pooled event rate, 0.57%; 95% confidence interval, 0.25%-0.89%). In an editorial, McNutt and Livingston Article discuss the need to consider the clinical context of individual patients in the application of evidence-based medicine.

“Despite its heroic ideals and noble intentions, the practice of medicine can strip us of some of our compassion.” From “An Oath to My Grandfather.”

Information harnessed from climate-monitoring satellites is helping scientists predict disease outbreaks, but aging infrastructure may limit the potential of this kind of surveillance.

Insulin therapy and cancer

Dietary sodium reduction: the case for caution

Electronic health records: monitoring and evaluation

Electronic health records: innovations in design and use

Call for Papers

Authors are invited to submit manuscripts for an upcoming JAMA theme issue.

Join David Reuben, MD, Wednesday, February 17, from 2 to 3 PM eastern time to discuss medical care in the final years of life. To register, go to http://www.ihi.org/AuthorintheRoom.

For your patients: Information about proteinuria.