HCA Healthcare (HCA (HCA)) is having a rough Tuesday. The hospital operator trimmed its profit forecast for the year, and investors responded by sending the stock down about 10% in premarket trading. By the time the regular session started, shares were still down 6.25% at $366.33.

The company now expects fiscal 2026 earnings of $28.70 to $30.50 per share, down from its previous range of $29.10 to $31.50. It also narrowed its revenue guidance to $77 billion to $79.5 billion, from $76.5 billion to $80 billion. Analysts had been expecting revenue of about $78.64 billion, so the new range is roughly in line with that.

But here's the thing: HCA's preliminary second-quarter results actually looked pretty good. Revenue came in at about $20.23 billion, up from $18.61 billion a year ago and above the consensus estimate of $19.39 billion. Net income was roughly $1.70 billion, or $7.62 per diluted share, compared with $1.65 billion, or $6.83 per share, in the same quarter last year. Adjusted EBITDA was about $4.03 billion, up from $3.85 billion.

So why the downbeat outlook? The answer lies in a shift in who's walking through the hospital doors — and whether they have insurance.

Admissions Growth Offsets Some Operational Weakness

On the operational side, HCA saw some encouraging trends. Same-facility admissions rose 2.5%, and equivalent admissions — which adjust for outpatient activity — increased 2.7%. Emergency room visits were also up 3.6% year over year. That's the kind of volume growth any hospital operator would welcome.

But there was a notable weak spot: surgeries. Same-facility inpatient surgeries declined 2.3%, and outpatient surgeries fell 3.4% compared with the second quarter of 2025. That's a meaningful drop, and it's part of what the company calls a "service mix shift" that's weighing on revenue.

Medicaid Payments Help Counter Payer Mix Pressure

The bigger challenge, though, is about who's paying the bills. HCA said the quarter saw a significant shift in payer mix as more patients became uninsured after losing health insurance exchange coverage. That shift had an estimated $400 million unfavorable impact on pretax income, including about $75 million related to an updated estimate of the first-quarter impact.

In other words, more people are showing up without insurance, and that's expensive for hospitals. HCA also noted that lower surgical volumes contributed to the service mix shift, but the uninsured issue was the main driver.

Partially offsetting those pressures were higher admissions, increased ER visits, improved expense trends, and — importantly — additional benefits from Medicaid Supplemental Payment Programs. During the quarter, HCA recognized about $400 million in incremental net benefits from these programs, largely related to Florida, covering the period from October 1, 2024, through June 30, 2026. That benefit reflects a state-directed payment program approved by the Centers for Medicare and Medicaid Services.

CEO Sam Hazen struck a confident tone in the company's statement: "Our colleagues continue to manage well through the positive and negative factors that have impacted our business in the first half of the year… As we look to the balance of the year, we have adjusted our guidance to reflect these factors. Moreover, we remain confident in our ability to navigate through this dynamic environment, maintain our focus and investments on improving patient care, and execute on our strategic plan to digitize and grow our healthcare networks."

Investors, for now, seem to be focusing on the guidance cut rather than the solid Q2 beat. But with admissions and ER visits still growing, and Medicaid payments providing a buffer, HCA's story isn't all bad — it's just a bit more complicated than it was a few months ago.