The Compounding Crisis: SUD, Comorbidities, and the Cost of Fragmented Care

A Condition That Rarely Exists Alone

The most recent national data makes the overlap between SUD and mental health conditions clear: among the 46.3 million adults with a substance use disorder in 2024, 45.8% had any mental illness and 14.9% had serious mental illness. These are not marginal overlaps. They are the norm.

SUD and mental health disorders share common risk factors including trauma, stress, challenging social environments, and inherited characteristics. The relationship is also bidirectional: having a mental disorder increases the risk of substance use, often as a form of self-medication, while having a SUD increases the risk of developing a mental disorder, as substances affect the same brain circuits involved in other mental health conditions.

The most common physical health conditions that co-occur with SUD are chronic pain, heart disease, cancer, HIV, and viral hepatitis. Chronic pain and SUD are tightly intertwined, as taking opioids on a long-term basis to manage pain increases the risk of developing opioid use disorder (OUD). Almost 50% of people with OUD also have chronic pain.

Treatment for mental health and physical health conditions without corresponding SUD treatment can result in escalating costs and patient readmissions, as a core component of the health concern has not been addressed. Nowhere is this more visible than in the consequences of injection drug use. When someone injects drugs using non-sterile equipment, bacteria enters the bloodstream directly and can migrate to the heart, causing infective endocarditis, a potentially life-threatening infection of the heart’s inner lining. This is distinct from the risk of HIV and hepatitis C, which are transmitted through contact with infected blood from another person when needles are shared. Both pathways lead to the same outcome: chronic, costly conditions that compound in severity when the underlying SUD goes unaddressed.

Treating endocarditis is estimated to cost between $50,000 and $200,000 for a single hospitalization. A study of patients hospitalized with injection drug use-associated endocarditis found that 49% were readmitted, and fewer than one in four received an addiction consultation during that initial stay. Researchers have described these patients as a “captive audience” for addiction care, noting the hospital setting is an ideal moment to initiate treatment, yet most leave without it. When patients whose addictions remain untreated undergo valve repair or replacement, the prosthetic material itself becomes a new infection site if injection drug use continues, setting up the very readmission cycle the surgery was meant to prevent.

Is Healthcare Part of the Problem?

Historically, SUD care has been handled separately from other mental health or physical health issues. With substance use often thought of as a social or criminal problem, services for individuals with SUD were not considered part of traditional healthcare. As a result, individuals with SUD who see clinicians for other reasons are not routinely screened for substance use risk factors, creating a critical knowledge gap for the doctors treating their comorbidities.

At the same time, there is a severe shortage of healthcare providers for individuals with SUD. As of 2023, nearly half of Americans live in areas with mental health professional shortages. Rural and remote parts of the country experience this most deeply, although the shortage is occurring nationwide. Without options for SUD-specialized care, individuals must rely on providers who are often not trained to address substance use.

Additionally, just as individuals with SUD face stigma in their communities, they can experience it from healthcare providers too. The barrier of stigma makes people less likely to disclose that they are struggling with substance use. A review of 19 studies found that 20% to 51% of health professionals held negative attitudes or beliefs about people with SUD, and a national study published in 2025 found that more than 30% of providers preferred not to work with patients with opioid or stimulant use disorders. When providers doubt treatment efficacy or hold stigmatizing beliefs, they are less likely to screen, refer, or treat. That becomes a system-level failure, not just an individual attitudinal one.

The separation of SUD care from traditional healthcare is an expensive oversight. Individuals with SUD and comorbidities are more likely to go to the emergency room or require a hospital stay, and they are more likely to return within 72 hours when the underlying condition goes unaddressed. In 2023, there were an estimated 7.59 million drug-related emergency department visits nationally, a 5.8% increase from 2022. Each visit that ends without a meaningful connection to ongoing care is both a missed clinical opportunity and a near-certain predictor of return.

The financial cost of this cycle is substantial and consistently confirmed across independent analyses. A 2023 CDC study published in JAMA Network Open found that SUD medical costs in the employer-sponsored insurance population alone total $35.3 billion annually, and the authors note this is a minimum estimate, as it excludes undiagnosed cases and indirect costs such as absenteeism and lost productivity. A NORC analysis using 2023 data found that mental health and substance use disorders combined carry an estimated $107.3 billion in annual costs including $59.5 billion in direct medical spending. Earlier research by A. Thomas McLellan, published in the Transactions of the American Clinical and Climatological Association, estimated direct medical costs from undiagnosed and untreated SUD across all payers at more than $120 billion annually.

Research demonstrates that incorporating addiction treatment services into standard healthcare settings would benefit both the substance use and general medical fields. Since substance use disorders are legitimate medical conditions that both influence and are influenced by other psychological and physical health issues, this integration could help reduce healthcare inequities, lower medical expenses for patients and families, and improve overall health outcomes.

Digital Options Can Help Bridge Gaps, Improve Outcomes

With the known shortage in SUD care providers and pressure on the healthcare system to keep costs low, digital solutions emerge as a cost-effective option to remove barriers to access and close gaps in care. Digital tools offer proactive, 24/7 engagement, quick access to interventions, comprehensive data to inform care and report on results, and seamless communication platforms to keep care teams connected to their patients between clinical encounters.

A systematic review published in Current Addiction Reports found that digital therapeutic products have proven successful in engaging patients in SUD treatment and reducing healthcare costs and resource utilization. These tools are particularly effective in reducing stigma as a barrier to engagement: patients who might not disclose substance use in a face-to-face encounter are more likely to engage honestly through a private, on-demand platform.

Multiple research studies, customer case studies, and impact reports indicate that the suite of digital solutions offered by CHESS Health delivers impressive real-world results, including:

• 90% Program Retention
• 71% increase in documented referrals with 99%+ case closure
• 30% increase in program adherence
• 88% boost in recovery confidence
• 94% engagement rate
• 37 more days in treatment

Source: CHESS Health impact reports and customer case studies

CHESS Health’s purpose-built SUD tools give existing care teams what they currently lack: early identification of at-risk patients, streamlined care coordination, and sustained recovery engagement, without adding headcount.

Treating the Whole Patient

Addiction is a complex problem that stretches across the spectrum of healthcare, creating challenges for professionals dedicated to improving outcomes for patients. However, when SUD is treated alongside mental health disorders and chronic health conditions, opportunities for improved results are seen in all areas. Working together to treat the whole patient requires care coordination at all levels of care, from primary care providers to behavioral health professionals to emergency room staff.

Making SUD screenings a routine part of healthcare and providing robust digital tools to ease the burden on staff and engage patients who need support are important steps in driving toward better health outcomes for individuals with comorbidities. Pairing technology with compassion can aid patients across the care continuum.