Sun Life’s 2026 High Cost Claims and Injectable Drug Trends report, released this summer and drawing on more than 70,000 high-dollar medical claims from more than 3,300 self-funded employers, elevated cardiovascular disease to the second-highest cost category in stop-loss claims, displacing orthopedic and musculoskeletal conditions from that position. Cancer and blood disorders retain the top spot; cardiovascular disease now sits directly behind them. The ranking shift matters for reserving because cardiovascular claims arrive on a different timeline than cancer claims and carry distinct comorbidity patterns; a plan that absorbed the orthopedic surge without revisiting its large-claim frequency model may now be two ranking shifts behind.
The headline number: million-dollar-plus claims rose 46% from 2022 to 2026. That is a frequency statement, not a severity statement. Severity has moved too, with blood cancers averaging $5.45 million per patient in 2025 and Elevidys, the gene therapy for Duchenne muscular dystrophy, averaging $3.6 million per patient. But the 46% frequency increase is the input that most self-funded IBNR (incurred but not reported) models are least likely to have incorporated, because large-claim frequency assumptions are typically calibrated against three to five years of the plan’s own experience, and the 2019 through 2021 base years predate the surge entirely.
Who it affects
Self-insured employers carrying specific stop-loss coverage are the primary audience, particularly plans with attachment points set before the 2022 renewal when the frequency distribution was still anchored to pre-surge experience. Group stop-loss captives face the same exposure with the added complexity that adverse development in one member plan can affect the captive’s aggregate layer. Public-entity self-insured pools and risk-retention groups sponsoring health benefits face the same recalibration need; the frequency shift is driven by treatment availability and disease prevalence, not plan structure.
The reserve mechanism
The stop-loss IBNR calculation depends on two inputs: the expected frequency of claims above the specific attachment point and the expected severity of each penetrating claim. The cardiovascular rise changes the frequency input in a way that is easy to miss.
Cancer claims are well-understood by stop-loss carriers and plan actuaries; onset-to-diagnosis patterns are relatively predictable and development lags are shorter than for cardiovascular events, which often involve cumulative conditions with longer latency before a large claim crystallizes. When cardiovascular disease moves from a secondary comorbidity to the primary driver of a catastrophic claim, the reporting pattern shifts as well, stretching the development tail.
The second lever is attachment point adequacy. Sun Life, Cigna, and Voya all reported adverse stop-loss claims experience for recent plan years, signaling higher specific attachment points and aggregate deductibles at 2026 and 2027 renewals. When a specific deductible rises, say from $250,000 to $350,000, the claims that previously breached the threshold now land entirely in the plan’s retained layer. The IBNR for that retained layer needs to expand to cover the newly retained cardiovascular frequency, but that recalibration rarely happens automatically. As detailed in the analysis of leveraged trend on fixed stop-loss attachments, each renewal cycle that raises the deductible without updating the retained-layer reserve embeds a shortfall that compounds.
GLP-1 (glucagon-like peptide-1 receptor agonist) high-dollar claims rose 24% year-over-year, adding a second tier of high-cost events that accumulates in aggregate stop-loss exposure. The cardiovascular category is where the frequency of specific-penetrating claims is changing most sharply.
What this means for your next review
Ask your actuary whether the large-claim frequency assumption in your stop-loss IBNR has been updated since 2022, and whether cardiovascular claims are modeled separately from cancer claims given their different reporting lag. If your specific attachment point is increasing at the next renewal, ask for a standalone IBNR on the newly retained layer between the old and new thresholds; that layer did not exist in the prior reserve but it has claims.
For context on how orthopedic conditions arrived in the high-cost top tier before being displaced, see Ortho and MSK Climb Into Stop-Loss High-Cost Top Three. For the reinsurance-level signal confirming that adverse experience is feeding through to plan-level pricing, see Stop-Loss Reinsurance at 15% Signals a Multi-Year Rate Floor.
Sources
- Sun Life 2026 High Cost Claims and Injectable Drug Trends Report
- Sun Life Newsroom: Cardiovascular Disease Rises to Second Place (2026)
- PR Newswire: Sun Life Releases Annual Report on Highest-Cost Medical Claims
- MedBen: Rising Million-Dollar Claims Challenge Employer Plans
- Captive Review: Medical Stop-Loss Captives Gain Traction as Million-Dollar Claims Rise