This Week in Family Medicine — May 21, 2026

Welcome to This Week in Family Medicine. This week we're covering 9 notable papers spanning large-scale prevention and screening, new insights into disease biology, and a look at the very foundations of our practice, from clinical trials to healthcare delivery. Let's dive in.

We start this week with three papers that push the boundaries of prevention and screening, from pre-conception to childhood to entire populations. First, a comprehensive review in JAMA provides a practical guide to prepregnancy care and counseling [9]. The authors highlight a sobering statistic: in the United States, roughly two-thirds of reproductive-aged women have at least one modifiable risk factor for adverse pregnancy outcomes. The review reinforces key interventions, noting that folic acid supplementation before pregnancy is associated with a one-third reduction in the risk of fetal neural tube defects. For patients with pre-existing diabetes, achieving a hemoglobin A1c below 6.5% is associated with a decreased risk of fetal anomalies. The article also underscores the harms of substance use, with maternal smoking, for instance, associated with a nearly 50% increased risk of stillbirth. Unintended pregnancies are linked to worse outcomes, including a roughly 50% higher odds of postpartum depression. The clear message is that routine primary care visits are a critical opportunity to discuss reproductive goals and implement risk-reducing strategies.

Moving from individual counseling to population-level programs, a study in JAMA reports on a massive screening effort for early-stage Type 1 diabetes in Germany [2].

The Study Investigators screened over 220,000 children aged approximately 2 to 11 years for islet autoantibodies. The primary outcome was the detection of presymptomatic, early-stage Type 1 diabetes, defined as having two or more autoantibodies.

Results They found an adjusted population frequency of early-stage disease of 0.3%, or about 3 in 1,000 children. Over a median follow-up of nearly 6 years, the five-year progression rate from an early-stage diagnosis to clinical, or stage 3, diabetes was 36.2%. The most clinically significant finding was that this progression rate was not significantly different between children with and without a first-degree family history of Type 1 diabetes.

Conclusions The findings suggest that general population screening can effectively identify children with early-stage disease and that risk of progression is similar regardless of family history. This may inform future disease-modifying therapy trials and supports considering screening beyond just genetically selected, high-risk populations.

Rounding out our theme on screening, a paper in Nature Medicine details the Hong Kong Genome Project, which provides a blueprint for implementing precision medicine in underrepresented populations [8]. The project sequenced over 20,000 participants. In a cohort of over 2,200 patients with suspected genetic diseases, they achieved a diagnostic rate of 25%. In a larger population cohort of over 18,000 individuals, analysis revealed that 3.7% carried pathogenic or likely pathogenic variants for dominant disorders. Critically, the study highlights the limitations of using data from other populations. When using a gene list based on European ancestries, analysis would have missed 38 clinically important recessive disorder genes relevant to the Chinese population. This underscores the absolute necessity of building diverse, population-specific genomic reference data to ensure equitable application of precision medicine.

Our next section shifts focus to papers that challenge us to think about the systems we work in, from how we design research to how we deliver care. A perspective piece in JAMA argues for treating primary care as a public utility [7]. The authors begin by stating that more than one-third of United States adults lack access to primary care, which has become more of a commodity than a common good. They argue that state-level efforts to bolster primary care are often stymied by the fragmentation of health insurance, leaving large portions of the population, like those with self-insured commercial plans or Medicare, untouched by state mandates. Their proposed solution is a 'primary care common fund,' which would pool primary care spending from all public and private payers and pay practices directly. This would create a single, stable funding stream, reduce administrative burden, and allow for payment flexibility, all without disrupting the insurance and payment systems for care outside of primary care.

This call for systemic change is echoed in a perspective from The New England Journal of Medicine titled 'Advancing Indigenous Health Equity in Medical School Curricula' [5]. While this piece did not include an abstract, its publication in a leading journal signals an important conversation about the need to fundamentally reform medical education to better address long-standing health disparities and improve care for Indigenous populations.

Finally, it's not just care delivery and education under the microscope; it's also our research methods. A paper in the BMJ introduces the CRT-Estimands Framework, a consensus-based extension of existing guidelines for clinical trials [1]. This framework specifically addresses cluster randomized trials, where groups of people, like clinics or communities, are randomized instead of individuals. These trials present unique challenges for precisely defining the treatment effect being measured. The new framework provides a set of attributes to describe, with the goal of making the research question crystal clear. For practicing physicians, this is important because clearer estimands mean we can better assess the relevance of a trial's results to our own patients and make more informed decisions based on the evidence.

Our final section brings us from systems down to biology, with new insights into anorexia nervosa, the maternal brain, and cellular metabolism. First, a large multi-cohort study in PLoS Medicine provides a detailed look at brain morphology in anorexia nervosa [6].

The Study Using a mega-analytic approach, researchers combined individual-level data from 11 international sites, including 570 female participants with anorexia nervosa and over 700 healthy controls. They examined cortical thickness, surface area, and subcortical volumes.

Results Analyses reinforced previous findings of pronounced and widespread gray matter deficits in acutely underweight patients with anorexia nervosa compared to controls. These alterations were so distinct that machine learning classifiers could reliably differentiate individuals with the condition from healthy controls with good accuracy, achieving an area under the curve between 0.75 and 0.81. However, in a direct comparison between anorexia subtypes—the restricting type versus the binge-eating/purging type—the study found no significant differences in brain structure. Individuals with different subtypes could not be reliably differentiated from each other.

Conclusions The authors conclude that while widespread gray matter deficits are a robust finding in anorexia nervosa, the lack of structural differences between subtypes may reflect a shared underlying neurobiology, at least in terms of brain structure that can be measured with MRI.

Next, two papers from Nature explore fundamental biological processes. The first identifies dopamine as a key driver of the persistent remodeling of the maternal brain [4]. Researchers combined transcriptomic profiling and single-cell RNA sequencing in mice to find that reproductive experience induces significant transcriptional changes in the dorsal hippocampal formation. They discovered that dopamine signaling drives these adaptations through a specific epigenetic mechanism called histone dopaminylation, which alters gene expression and behavior. Importantly, they found conserved patterns of these changes in human brain tissue, suggesting dopamine is a central regulator of parity-induced neuroadaptations in both humans and mice.

Our final paper, also in Nature, challenges the long-held view of a metabolite called L-2-hydroxyglutarate, or L-2-HG, as being purely toxic [3]. In humans, a lack of the enzyme that clears L-2-HG leads to its accumulation and causes a rare and severe neurologic disease. However, this study investigated whether L-2-HG might also have a physiological function. The researchers found that L-2-HG levels are actively regulated in mitochondria and that it acts as a signaling molecule, repressing specific genes. To test its function in vivo, they overexpressed the enzyme that *removes* L-2-HG in mice. This systemic reduction of L-2-HG actually impaired postnatal growth, caused mortality, and led to kidney damage. This work establishes L-2-HG as a physiological signaling metabolite and suggests that some molecules previously regarded only as toxic byproducts may in fact have crucial biological roles.

If you only have time for one paper this week, make it the review on Prepregnancy Care and Counseling in JAMA [9]. It's a highly practical, evidence-based summary of interventions every primary care physician can and should be implementing. With two-thirds of reproductive-aged women in the United States having a modifiable risk factor, this article provides a clear roadmap to improving maternal and infant outcomes, starting in our clinics today.

Here are the key takeaways from this week in Family Medicine:

First: Start prepregnancy counseling now. Review key interventions like folic acid supplementation, immunizations, substance use screening, and chronic disease optimization, especially for conditions like diabetes where an A1c under 6.5% is crucial [9].

Second: Population screening for early-stage Type 1 Diabetes may be on the horizon. A large German study found that progression to clinical disease was independent of family history, suggesting broader screening could be beneficial [2].

Third: In patients with anorexia nervosa, expect significant and widespread gray matter changes. However, current evidence does not show structural brain differences between restricting and binge-eating/purging subtypes, suggesting they may share a common underlying neurobiology [6].

Fourth: Genomic screening data is not one-size-fits-all. A major project from Hong Kong demonstrates that ancestry-specific data is critical, as European-based gene panels miss dozens of clinically important genes in Chinese populations [8].

And Fifth: The conversation around primary care reform is shifting towards treating it as a public utility. A proposal in JAMA for a 'common fund' to pool resources and pay practices directly is gaining traction as a way to solve access and equity issues in the United States [7].

That's your roundup for This Week in Family Medicine. The full transcript and references are available on the episode page in your AudioScholar library. This is an AI-curated summary — for clinical decisions, always consult primary sources and current guidelines. See you next week.

This is an automated summary generated by artificial intelligence, which can make mistakes. Always review the original source materials.