Artificial intelligence is driving a measurable increase in U.S. healthcare spending by enabling hospitals to bill for more complex and expensive care. A new analysis from the Blue Cross Blue Shield Association (BCBSA) found that AI-assisted hospital coding added $942 million in healthcare spending over a two-year period spanning 2024 and 2025.
The increase is largely attributed to “upcoding,” a practice where AI software scans medical records to identify secondary conditions that might have been overlooked by human coders. While hospitals argue these tools provide a more accurate picture of patient health, insurers claim the technology is being used to move thousands of cases into higher-paying reimbursement categories without a corresponding change in the actual treatment provided.
The $12,000 Shift
The BCBSA report highlights a significant shift in how inpatient care is categorized. The share of claims billed as “medically complex” rose from 37% in early 2023 to 40% by late 2025. This three-percentage-point increase represents more than 55,000 hospital stays that were reclassified into higher-paying Diagnosis-Related Group (DRG) categories.
When AI-assisted coding shifts a patient into a more complex category, the financial impact is substantial. Hospitals received an average of nearly $11,800 more per case following these reclassifications. Approximately $653 million—or 70% of the total spending increase identified in the study—was driven specifically by secondary diagnoses found by AI tools in patient records.
Clinical examples cited in the research show that for major bowel surgeries, the documentation of secondary conditions like intestinal blockages surged by up to 55% between 2023 and 2025. Other common additions include secondary diagnoses for low sodium or anemia, which can trigger higher reimbursement tiers even if they do not fundamentally alter the surgical or medical intervention required for the primary ailment.
The Administrative “Bot War”
The rise of AI in billing has created what industry analysts describe as an administrative “bot war.” As hospitals deploy AI to maximize revenue through precision coding, insurers are counter-deploying their own AI algorithms to automate claim denials and flag “discordant” billing patterns. This cycle creates a loop where software on both sides of the transaction is increasingly responsible for the flow of billions of dollars in medical payments.
CMS Administrator Dr. Mehmet Oz warned that AI will “turbocharge” billing systems and inflate costs before potentially lowering them.
Hospital Industry Response
The BCBSA analysis maintains that the speed and volume of these reclassifications suggest a technological shift rather than a sudden demographic change. The report notes that the reclassified cases showed no observable increase in the intensity of treatment or length of stay, pointing to a “discordance” between the recorded complexity of the patient and the actual care delivered on the hospital floor.
