Robot pen pals: a systematic analysis of recent trends in scientific correspondence

Abstract Background Current research evaluation metrics emphasize publication quantity, creating incentives for rapid outputs. Letters to the editor (LTEs), a usually brief form of post-publication peer review, are increasingly exploited under the pressures of the “publish or perish” culture because they are citable, lightly regulated, and often bypass the peer-review process. Their textual format, typically short, minimally referenced, and frequently not peer reviewed, makes LTEs particularly easy to generate using large language models, raising concerns about the potential for artificial intelligence (AI)-assisted publication inflation. Since the introduction of AI chatbots in 2022, LTE submissions have surged, with some authors producing rapidly increasing numbers of letters. Methods We investigate the role of generative AI in LTE production and propose strategies to mitigate this emerging issue. We downloaded more than 780,000 LTE records indexed in PubMed from 2005 to 2025. Using descriptive statistics, we analyzed temporal trends and interpreted them using an epidemiological perspective, classifying authors exhibiting unusually rapid growth in correspondence output, and assessed their proportional contributions to annual LTE publications. Results The mean annual number of LTEs per author shows three distinct accelerated growth years: in 2013, associated with MEDLINE indexing changes; in 2020, coinciding with the COVID-19 pandemic; and in 2023 to date, aligning with the widespread adoption of generative AI. From an epidemiological perspective, the post-LLM period is marked by an increase in the prevalence of high-output authors, with newly debuting researchers more likely to produce multiple LTEs in their first year. Conclusions The study identifies 2023–2025 as a period of anomalous LTE growth associated with the rise of AI language models, suggesting that AI may contribute to publication inflation and highlighting the need for safeguards in scientific communication.