Drew Asher
Executive Vice President & Chief Financial Officer at Centene
Thank you, Sarah.
Today, we reported first quarter 2024 results, including $36.3 billion in premium and service revenue and adjusted diluted earnings per share of $2.26 in the quarter, 7% higher than Q1 of 2023. This result was better than our expectations and we are increasing full-year 2024 adjusted EPS guidance by $0.10 to greater than $6.80.
This quarter is a good example of the benefit of a diversified business with multiple levers to drive results. Our Q1 consolidated HBR was 87.1%, which is right on track for our full-year guidance. Here's an example of the benefit of that diversification since we provide you with transparency into the line of business components. Medicaid at 90.9% was a little higher in the quarter than we expected as we continue to work through the appropriate matching of rates and acuity in the short-term. Redeterminations are certainly front and center in the acuity rate match process, but getting the right match for other circumstances, such as states changing pharmacy programs or behavioral health practices, are also important initiatives in a handful of states.
On the other hand, our commercial HBR at 73.3% was a little better than we had planned in the quarter, driven by the continued strength of our marketplace business, and our Medicare segment at 90.8% was right on track in the quarter, all of this netting out to 87.1%, a good result.
Going a little bit deeper into each of our business lines. Medicaid membership at 13.3 million members was slightly better than the 13.2 million members we reforecast -- we forecasted as of Q1 -- for Q1 as our invest -- as of our Investor Day. Drivers of membership for the remainder of the year include, one, new wins such as Oklahoma and Arizona LTSS; two, the return of slight growth in markets once redeterminations are complete, plus the rejoiners dynamic; net of three, the substantial wind-down of redeterminations over the next three months to four months.
Upon reforecasting the sloping of membership and revenue for 2024, including Q1 membership being a little bit higher than planned, we added $1 billion of Medicaid premium revenue to our 2024 guidance. The overall composite rate is running a little above the 2.5% we last referenced, and we have over 75% member month rate visibility into the 2024 calendar year. Regardless of the temporary work to match rates and acuity, our long-term goal remains to return to the high-89s HBR as we look out over the 2025-2026 timeframe.
All things considered, we are pretty pleased with the performance of our Medicaid business one year into a very complex redetermination process. And as Sarah covered, we cannot be more pleased with our performance in recent Florida and Michigan Medicaid RFPs. The Texas protest process still needs to play-out.
Our commercial business performed very well in the quarter in terms of both growth and HBR. Consistent with previous comments, we grew from 3.9 million Marketplace members at year-end to 4.3 million at the end of Q1. For the past two years, we have consistently delivered a combination of growth, coupled with improving margin. Our guidance assumes that we stay at 4.3 million Marketplace members for the rest of 2024. If we can grow during the special enrollment period, which we've been able to do in the past two years, there would be upside to our premium and service revenue guidance. So, stay-tuned.
Our current 2024 guidance assumes about $16 billion of Medicare Advantage revenue, representing 12% of total premium and service revenue guidance and approximately $4 billion of PDP revenue. I previously mentioned at a conference that Medicare inpatient authorizations were higher than expected in January and February. March authorizations ended up being lower than February, though still elevated from Q4. And Medicare outpatient trend continues at the elevated level we first saw in Q2 of 2023, though reasonably steady. Nonetheless, the performance in the quarter for the Medicare segment was in-line with our expectations and our full-year view has not changed. We had good performance with our new pharmacy cost structure and executed well on other operating levers.
As we look ahead, I feel like we are making 2025 decisions with our eyes wide open. Inpatient and outpatient trends, complex pharmacy changes from the Inflation Reduction Act, an insufficient 2025 rate environment based upon the final rate notice and a risk model being phased-in beginning in 2024 that is punitive to partial and full duals. It also seems like many of our peers should have more religion in setting benefits at sustainable levels, given these headwinds.
I'll repeat what I said on the mic at a conference in March. To accomplish our strategic goals with our Medicare Advantage business, it doesn't matter if we ultimately level-off at $14 billion, $15 billion or $16 billion of Medicare Advantage revenue, what is strategically important is the alignment with Medicaid and those complex populations we want to serve, especially given where the puck is heading with regulations pulling duals and Medicaid closer together.
We're still in the process of making 2025 county-by-county decisions, and we'll finalize and submit Medicare bids in early June. So, we'll provide you with more 2025 Medicare commentary on our Q2 call. We expect Medicare to be a good business for us in the long-run, and it's an important part of our overall portfolio. We need to deliver on Stars' improvements, clinical levers and SG&A actions over the next few years, and those efforts remain on track.
Going to other P&L and balance sheet items. Our adjusted SG&A expense ratio was 8.7% in the first quarter, consistent with our updated mix of business, including growth in Marketplace. Cash flow used in operations was $456 million for Q1, primarily driven by net earnings, more than offset by the timing of risk corridor payments, a delay in March's premium payment from one of our large state partners, subsequently received in early April, and slower receipt of pharmacy rebates as we transition to a new third-party PBM in January of 2024.
From January 1 through mid-April, we repurchased 3.4 million shares of our common stock for $251 million. Our share repurchase goal for 2024 is unchanged at $3.0 billion to $3.5 billion. Our debt-to-adjusted EBITDA was 2.9 times at quarter-end, consistent with year-end. And during Q1, we were pleased to maintain our S&P BBB- rating under the updated S&P rating model. Our medical claims liability at quarter-end represented 53 days in claims payable, down one day from Q1 and Q4 of 2023. DCP was actually up due to change healthcare claims receipt delays, then backed down due to an acceleration of state-directed payments to providers and lower pharmacy invoices outstanding at quarter-end. You'll see in the reserve table that our 2024 Medicare Advantage PDR is up $50 million in the quarter. This progression in the 2024 PDR was expected and planned for due to quarterly seasonality in Medicare Advantage.
Though it's early in the year, we are comfortable adding $1 billion of premium and service revenue and $0.10 of adjusted EPS to our 2024 guidance. You'll also see some mechanical changes to total revenue driven by pass-through premium taxes and the GAAP effective tax-rate due to the Circle divestiture. We also expect investment income to be a little bit above our previous forecast of $1.4 billion, while still providing for a few rate cuts in 2024.
Q1 was a quarter of momentum. We put another quarter of redeterminations behind us. We reprocured one of our largest contracts and are well-positioned in Florida. We executed well in the marketplace annual enrollment period and put up a strong quarter of both growth and margin. We delivered on the January 1 PBM conversion and our businesses and customers are benefiting from an improved cost structure. We continue to advance our multi-year operational improvements and Centene continues to attract talent. And all of this resulted in strong Q1 results and increased 2024 guidance. While there's plenty more to achieve, we are off to a good start in 2024.
Thank you for your interest in Centene. Rocco, please open the line up for questions.