Effect of Out-of-Pocket Costs on Subsequent Mammography Screening.

OBJECTIVE: Although the Affordable Care Act eliminated cost sharing for screening mammography, a concern is that grandfathered plans, diagnostic mammograms, and follow-up testing may still lead to out-of-pocket (OOP) spending. Our study examines how OOP spending among women at their baseline screening mammogram may impact the decision to receive subsequent screening. METHODS: The study included commercially insured women aged 40 to 41 years with a screening mammogram between 2011 and 2014. We estimated multivariate linear probability models of the effect of OOP spending at the baseline mammogram on subsequent screening 12 to 36 months later. RESULTS: Having any OOP payments for the baseline screening mammogram significantly reduced the probability of screening in the subsequent 12 to 24 months by 3.0 percentage points (pp) (95% confidence interval [CI]: 1.1-4.8 pp decrease). For every $100 increase in the OOP expenses for the baseline mammogram, the likelihood of subsequent screening within 12 to 24 months decreased by 1.9 pp (95% CI: 0.8-3.1 pp decrease). Similarly, any OOP spending for follow-up tests resulting from the baseline screening led to a 2.7 pp lower probability of screening 12 to 24 months later (95% CI: 0.9-4.1 pp decrease). Higher OOP expenses were associated with significantly lower screening 24 to 36 months later (coefficient = -0.014, 95% CI: -0.025 to -0.003). DISCUSSION: Although cost sharing has been eliminated for screening mammograms, OOP costs may still arise, particularly for diagnostic and follow-up testing services, both of which may reduce rates of subsequent screening. For preventive services, reducing or eliminating cost sharing through policy and legislation may be important to ensuring continued adherence to screening guidelines.

Medical Service Use and Charges for Cancer Care in 2018 for Privately Insured Patients Younger Than 65 Years in the US.

Importance: Currently, there are limited published data regarding resource use and spending on cancer care in the US. Objective: To characterize the most frequent medical services provided and the associated spending for privately insured patients with cancer in the US. Design, Setting, and Participants: This cohort study used data from the MarketScan database for the calendar year 2018 from a sample of 27.1 million privately insured individuals, including patients with a diagnosis of the 15 most prevalent cancers, predominantly from large insurers and self-insured employers. Overall societal health care spending was estimated for each cancer type by multiplying the mean total spending per patient (estimated from MarketScan) by the number of privately insured patients living with that cancer in 2018, as reported by the National Cancer Institute's Surveillance, Epidemiology, and End Results program. Analyses were performed from February 1, 2018, to July 8, 2021. Exposures: Evaluation and management as prescribed by treating care team. Main Outcomes and Measures: Current Procedural Terminology and Healthcare Common Procedure Coding System codes based on cancer diagnosis code. Results: The estimated cost of cancer care in 2018 for 402 115 patients with the 15 most prevalent cancer types was approximately $156.2 billion for privately insured adults younger than 65 years in the US. There were a total of 38.4 million documented procedure codes for 15 cancers in the MarketScan database, totaling $10.8 billion. Patients with breast cancer contributed the greatest total number of services (10.9 million [28.4%]), followed by those with colorectal cancer (3.9 million [10.2%]) and prostate cancer (3.6 million [9.4%]). Pathology and laboratory tests contributed the highest number of services performed (11.7 million [30.5%]), followed by medical services (6.3 million [16.4%]) and medical supplies and nonphysician services (6.1 million [15.9%]). The costliest cancers were those of the breast ($3.4 billion [31.5%]), followed by lung ($1.1 billion [10.2%]) and colorectum ($1.1 billion [10.2%]). Medical supplies and nonphysician services contributed the highest total spent ($4.0 billion [37.0%]), followed by radiology ($2.1 billion [19.4%]) and surgery ($1.8 billion [16.7%]). Conclusions and Relevance: This analysis suggests that patients with breast, colorectal, and prostate cancers had the greatest number of services performed, particularly for pathology and laboratory tests, whereas patients with breast, lung, lymphoma, and colorectal cancer incurred the greatest costs, particularly for medical supplies and nonphysician services. The cost of cancer care in 2018 for the 15 most prevalent cancer types was estimated to be approximately $156.2 billion for privately insured adults younger than 65 years in the US.

Potential Winners and Losers: Understanding How the Oncology Care Model May Differentially Affect Hospitals.

PURPOSE: With the introduction of the Oncology Care Model and plans for the transition to Oncology Care First, alternative payment models (APMs) are an increasingly important piece of the oncology care landscape. Evidence is mixed on the Oncology Care Model's impact on utilization and costs, but as policymakers consider expansion of similar models, it is critical to understand the characteristics of hospitals that may be differentially affected. METHODS: We used 2007-2016 SEER-Medicare data to identify patients with breast and prostate cancer receiving chemotherapy, endocrine therapy (breast), or androgen deprivation therapy (prostate). For each hospital, we calculated 6-month expected mortality, emergency department (ED) visits, inpatient admissions, and costs, all commonly collected APM outcomes. After calculating observed-to-expected rates for each outcome by hospital, we estimated the association between observed-to-expected rates and characteristics of each hospital to understand hospital characteristics that might be associated with higher- or lower-than-expected rates of each outcome. RESULTS: Hospitals with > 15% rural patients had significantly higher-than-expected mortality (0.31 points higher, P < .001) and ED visit rates (0.10 points higher, P = .029) as well as significantly lower costs (0.06 points lower, P = .004). Hospitals unaffiliated with a medical school also experienced significantly higher-than-expected mortality and ED visits. Hospitals eligible for disproportionate share hospital payment experienced significantly higher ED visits but lower costs. For-profit hospitals experienced higher-than-expected mortality. CONCLUSION: Rural hospitals and those unaffiliated with a medical school may require special consideration as APMs expand in oncology care. Designated cancer centers and larger hospitals may be advantaged.

Health Savings Plans and Disparities in Access to Care by Race and Ethnicity.

INTRODUCTION: High-deductible health plans are often touted to motivate patients to become informed healthcare purchasers; however, racial/ethnic minorities report that high deductibles prevent them from seeking the needed care. One proposed way to mitigate the financial burden of high-deductible health plans is the use of health savings plans. This cross-sectional study investigates whether chronically ill Blacks and Hispanics enrolled in high-deductible health plans experience greater access to care difficulties than non-Hispanic Whites and whether racial/ethnic disparities are mitigated by the use of health savings plans. METHODS: Weighted, multivariate, linear probability regression models were estimated (analyses were conducted in December 2020), adjusting for individual attributes and contextual factors that may explain the variation in health care access. Chronically ill, U.S.-born Black, Hispanic, and White adults enrolled in a high-deductible health plan from the National Health Interview Survey in 2011-2018 were included. Associations were tested among 3 independent variables-being Black, being Hispanic, and health savings plan utilization (and their interaction)-and access to healthcare outcomes of interest, including affordability-related access, provider-related access, and delayed care. RESULTS: Blacks and Hispanics were less likely to use health savings plans, and Blacks were more likely to experience problems with access to health care. Although the use of health savings plans was found to have a minimal effect on reducing racial/ethnic disparities in affordability-related access, there was also evidence that health savings plans compounded racial/ethnic disparities in provider-related access. CONCLUSIONS: Understanding how health savings plans function to improve access to care within racial/ethnic minority groups may help to inform policy approaches related to their use.

Comparative Effectiveness of a Complex Care Program for High-Cost/High-Need Patients: a Retrospective Cohort Study.

BACKGROUND: High-cost/high-need (HCHN) adults and the healthcare systems that provide their care may benefit from a new patient-centered model of care involving a dedicated physician and nurse team who coordinate both clinical and social services for a small patient panel. OBJECTIVE: Evaluate the impact of a Complex Care Program (CCP) on likelihood of patient survival and hospital admission in 180 days following empanelment to the CCP. DESIGN: Retrospective cohort study using a quasi-experimental design with CCP patients propensity score matched to a concurrent control group of eligible but unempaneled patients. SETTING: Kaiser Permanente Mid-Atlantic States (KPMAS) during 2017-2018. PARTICIPANTS: Nine hundred twenty-nine CCP patients empaneled January 2017-June 2018, 929 matched control patients for the same period. INTERVENTIONS: The KPMAS CCP is a new program consisting of 8 teams each staffed by a physician and nurse who coordinate care across a continuum of specialty care, tertiary care, and community services for a panel of 200 patients with advanced clinical disease and recent hospitalizations. MAIN OUTCOMES: Time to death and time to first hospital admission in the 180 days following empanelment or eligibility. RESULTS: Compared to matched control patients, CCP patients had prolonged time to death (hazard ratio [HR]: 0.577, 95% CI: 0.474, 0.704), and CCP decedents had longer survival (median days 69.5 vs. 53.0, p=0.03). CCP patients had similar time to hospital admission (HR: 1.081, 95% CI: 0.930, 1.258), with similar results when adjusting for competing risk of death (HR: 1.062, 95% CI: 0.914, 1.084). LIMITATIONS: Non-randomized intervention; single healthcare system; patient eligibility limited to specific conditions. CONCLUSION: The KPMAS CCP was associated with significantly reduced short-term mortality risk for eligible patients who volunteered to participate in this intervention.

Coverage, Financial Burden, and the Patient Protection and Affordable Care Act for Patients With Cancer.

PURPOSE: Evidence suggests coverage has improved significantly for patients with cancer, particularly in the lower-income population, after the implementation of the Affordable Care Act (ACA). Yet no study has examined changes in type of coverage or the resulting effect on spending and financial burden. METHODS: Using 2011 to 2015 Medical Expenditure Panel Survey data, we examine changes in type of coverage, spending, and financial burden among lower-income (< 400% of federal poverty level [FPL]) individuals diagnosed with cancer after the ACA. To better understand the changes, we compare this sample to the lower-income patients without cancer and patients with cancer with a higher income (≥ 400% of FPL). All analyses were conducted in 2018. RESULTS: In adjusted analyses, we found a decline in months uninsured (-0.78 months; P = .001) and an increase in months with Medicaid coverage (0.40 months; P = .059) among the lower-income patients with cancer. This change is similar to the lower-income patients without cancer. We found an increase in total expenditures ($3,020; P = .071) but a modest decline in the fraction of family income spent on health (-0.014; P = 0.099), although neither is statistically significant. For the higher income patients with cancer, we observed significant increases in both out-of-pocket premiums and medical financial burden. CONCLUSION: After the ACA, lower-income people diagnosed with cancer experienced significant gains in coverage largely through Medicaid at rates similar to lower-income patients without cancer, but patients with cancer with incomes 400% or greater of FPL faced a higher financial burden.

Opioid misuse, labor market outcomes, and means-tested public expenditures: a conceptual framework.

As the opioid epidemic has drawn increased attention, many researchers are attempting to estimate the financial burden of opioid misuse. These estimates have become particularly relevant as state and local governments have begun to take legal action against pharmaceutical manufacturers, distributors, and others who are identified as being potentially responsible for the worsening epidemic. An important category of costs includes those related to the effect of opioid misuse on labor market outcomes and productivity. Most published estimates of opioid-attributable productivity losses estimate the financial burden borne by society, failing to distinguish between costs internalized by individuals and those that spill over to third parties, such as state and federal governments. This article provides an overview and a conceptual framework for 2 types of labor market-related costs borne by state and federal governments that typically have not been incorporated into existing estimates, which may represent important categories of expenditures. Because detailed estimates of lost tax revenue are available elsewhere, this article focuses largely on whether, and how, to incorporate opioid-related expenses incurred by means-tested government programs into more general estimates of the economic harm created by the opioid epidemic.

Association Between Hospitals' Risk-Adjusted Emergency Department Visits and Survival and Costs in Kidney Cancer Patients Undergoing Nephrectomy.

PURPOSE: To estimate the association between a hospital's risk-adjusted emergency department (ED) visit rate and its risk-adjusted mortality rate and costs among kidney cancer patients undergoing initial nephrectomy. PATIENTS AND METHODS: Using 2007-2012 Surveillance, Epidemiology, and End Results (SEER)-Medicare data, we used logistic regression to model ED visit occurrence within 30 and 365 days for all kidney cancer patients receiving initial surgery. Our model controlled for demographics, stage, histology, systemic targeted therapy, and comorbidities. Based on model predictions, we created a ratio of actual versus predicted ED visits for hospitals to identify hospitals with higher and lower than predicted ED visit rates. We estimated the association between the hospitals' ED visit ratio and hospitals' risk-adjusted 365-day mortality rates, and 6- and 12-month total costs and total costs (less ED visits). RESULTS: In our sample of 6078 patients, 15.5% had an ED visit within 30 days of surgery and 43.5% within 365 days. For hospitals with ≥ 11 patients, we found no statistically significant association between 30-day or 365-day risk-adjusted ED visit rate and their 365-day risk-adjusted mortality rate. Hospitals' 30-day ED visit rates were not significantly associated with either 6- or 12-month costs. However, hospitals' 365-day ED visit rates were significantly associated with 12-month costs, even when excluding the cost of the ED visit. CONCLUSION: Our results suggest hospitals' risk-adjusted ED visit rates capture a qualitatively different measure of quality than the more commonly reported mortality rates. Longer term ED visit rates are significantly associated with increased costs while 30-day ED visits are not.

Revenue Losses to State and Federal Government From Opioid-related Employment Reductions.

OBJECTIVE: The main purpose of this study was to estimate the tax revenue lost by state and federal governments as a result of adverse labor market outcomes attributable to opioid misuse. METHODS: We pair existing, plausibly causal estimates of the effect of opioid misuse on the decline in the labor force from 2000 to 2016 with a variety of data sources to compute tax revenues lost by state and federal governments using the online TAXSIM calculator. RESULTS: We find that between 2000 and 2016, opioid misuse cost state governments $11.8 billion, including $1.7 billion in lost sales tax revenue and $10.1 billion in lost income tax revenue. In addition, the federal government lost $26.0 billion in income tax revenue. CONCLUSIONS: By omitting lost tax revenue due to labor force exits, prior studies have missed an important component of opioid-related costs borne by state and federal governments. POLICY IMPLICATIONS: As more states and the federal government contemplate litigation for opioid-related damages, lost tax revenue represents an important cost that could be recouped and allocated to opioid prevention and treatment programs.

Medicaid enrollment among previously uninsured Americans and associated outcomes by race/ethnicity-United States, 2008-2014.

OBJECTIVES: To examine the person-level impact of Medicaid enrollment on costs, utilization, access, and health across previously uninsured racial/ethnic groups. DATA SOURCE: Medical Expenditure Panel Survey, 2008-2014. STUDY DESIGN: We pooled multiple 2-year waves of data to examine the direct impact of Medicaid enrollment among uninsured Americans. We compared changes in outcomes among nonpregnant, uninsured individuals who gained Medicaid (N = 963) to those who remained uninsured (N = 9784) using a difference-in-differences analysis. PRINCIPAL FINDINGS: Medicaid enrollment was associated with significant increases in total health care costs and total prescription drug costs and a significant decrease in out-of-pocket costs. Among those who gained Medicaid, prescription drug use increased significantly relative to those who remained uninsured. Medicaid enrollment was also associated with a significant increase in reporting a usual source of care, a decrease in foregone care, and significant improvements in severe psychological distress. Changes in total prescription drug costs and total prescription drug fills differed significantly across each racial/ethnic group. CONCLUSIONS: Among a national sample of uninsured individuals, Medicaid enrollment was associated with substantial favorable changes in out-of-pocket costs, prescription drug use, and access to care. Our findings suggest Medicaid is an important tool to reduce insurance-related disparities among Americans.

Availability and variation of publicly reported prescription drug prices.

OBJECTIVES: To examine how often retail prices for prescription drugs are available on state public reporting websites, the variability of these reported prices, and zip code characteristics associated with greater price variation. STUDY DESIGN: Searches of state government-operated websites in Michigan, Missouri, New York, and Pennsylvania for retail prices for Advair Diskus (250/50 fluticasone propionate/salmeterol), Lyrica (pregabalin 50 mg), Nasonex (mometasone 50 mcg nasal spray), Spiriva (tiotropium 18 mcg cp-handihaler), Zetia (ezetimibe 10 mg), atorvastatin 20 mg, and metoprolol 50 mg. METHODS: Data were collected for a 25% random sample of 1330 zip codes. For zip codes with at least 1 pharmacy, we used χ2 tests to compare how often prices were reported. For zip codes with at least 2 reported prices, we used Kruskal-Wallis tests to compare the median difference between the highest and lowest prices and a generalized linear model to identify zip code characteristics associated with greater price variation. RESULTS: Price availability varied significantly (P <.001) across states and drugs, ranging from 52% for metoprolol in Michigan to 1% for atorvastatin in Michigan. Price variation also varied significantly (P <.001) across states and drugs, ranging from a median of $159 for atorvastatin in Pennsylvania to a median of $24 for Nasonex in Missouri. The mean price variation was $52 greater (P <.001) for densely populated zip codes and $60 greater (P <.001) for zip codes with mostly nonwhite residents. CONCLUSIONS: Publicly reported information on state prescription drug price websites is often deficient. When prices are reported, there can be significant variation in the prices of prescriptions, which could translate into substantial savings for consumers who pay out-of-pocket for prescription drugs.

The Effect of False-positive Mammograms on Antidepressant and Anxiolytic Initiation.

BACKGROUND: Despite reported increases in anxiety following a false-positive mammogram, there is little evidence the effect rises to the clinical level of initiating medication. OBJECTIVE: To analyze the effect of a false-positive mammogram on antidepressant or anxiolytic initiation and identify subpopulations most at risk. SUBJECTS: MarketScan commercial and Medicaid claims databases used to identify women ages 40-64 undergoing screening mammography with no prior antidepressant or anxiolytic claims. RESEARCH DESIGN: Using a retrospective cohort design, we estimated the effects of a false-positive relative to a negative mammogram on the likelihood of initiating antidepressants or anxiolytics using multivariate logistic models estimated separately by insurance type. RESULTS: At 3 months after a false-positive mammogram, the relative risk (RR) for antidepressant or anxiolytic initiation was 1.19 [95% confidence interval (CI), 1.06-1.31] for the commercially insured and 1.13 (95% CI, 0.96-1.29) in the Medicaid population. In addition, 4 subgroups were at particularly elevated risk: commercially insured women ages 40-49 (RR=1.33; 95% CI, 1.13-1.54) or whose false-positive required multiple tests to resolve (RR=1.37; 95% CI, 1.17-1.57), included a biopsy (RR=1.68; 95% CI, 1.18-2.17), or whose resolution took >1 week (RR=1.21; 95% CI, 1.07-1.34). CONCLUSIONS: False-positive mammograms were associated with significant increases in antidepressant or anxiolytic imitation among the commercially insured. Follow-up resources may be particularly beneficial for cases taking longer to resolve and involving biopsies or multiple tests. The results highlight the need to resolve false-positives quickly and effectively and to monitor depressive symptoms following a positive result.

Medical costs of CKD in the Medicare population.

Estimates of the medical costs associated with different stages of CKD are needed to assess the economic benefits of interventions that slow the progression of kidney disease. We combined laboratory data from the National Health and Nutrition Examination Survey with expenditure data from Medicare claims to estimate the Medicare program's annual costs that were attributable to CKD stage 1-4. The Medicare costs for persons who have stage 1 kidney disease were not significantly different from zero. Per person annual Medicare expenses attributable to CKD were $1700 for stage 2, $3500 for stage 3, and $12,700 for stage 4, adjusted to 2010 dollars. Our findings suggest that the medical costs attributable to CKD are substantial among Medicare beneficiaries, even during the early stages; moreover, costs increase as disease severity worsens. These cost estimates may facilitate the assessment of the net economic benefits of interventions that prevent or slow the progression of CKD.

Cost-effectiveness of epidermal growth factor receptor mutation testing and first-line treatment with gefitinib for patients with advanced adenocarcinoma of the lung.

BACKGROUND: Epidermal growth factor receptor (EGFR) testing and first-line therapy with gefitinib for patients with activating mutations is quickly becoming the standard option for the treatment of advanced lung adenocarcinoma. Yet, to date, little is known about the cost-effectiveness of this approach. METHODS: A decision-analytic model was developed to determine the cost-effectiveness of EGFR testing and first-line treatment with gefitinib for those patients who harbor activating mutations versus standard care, which includes first-line treatment with chemotherapy followed by gefitinib as second-line treatment. The model uses clinical and outcomes data from randomized clinical trials and societal costs from Singapore cancer centers. Health effects were expressed as quality-adjusted life-years. All costs and cost-effectiveness ratios were expressed in 2010 Singapore dollars. Sensitivity and different scenarios analyses were conducted. RESULTS: EGFR testing and first-line treatment with gefitinib is a dominant strategy (with lower costs and greater effectiveness) compared with standard care. Because the primary savings result from not providing gefitinib to those who are not likely to benefit, this finding holds regardless of the prevalence of activating mutations. In a secondary analysis, first-line treatment with gefitinib was also dominant when compared with first-line chemotherapy in patients with activating EGFR mutations. CONCLUSIONS: This strategy can be considered a new standard of care and should be of great interest for health care payers and decision makers in an era in which our greatest challenge is to balance hard-won and incremental, yet small, improvements in patient outcomes with exponentially rising costs.

Cost-effectiveness of bariatric surgery for severely obese adults with diabetes.

OBJECTIVE: To analyze the cost-effectiveness of bariatric surgery in severely obese (BMI >or=35 kg/m(2)) adults who have diabetes, using a validated diabetes cost-effectiveness model. RESEARCH DESIGN AND METHODS: We expanded the Centers for Disease Control and Prevention-RTI Diabetes Cost-Effectiveness Model to incorporate bariatric surgery. In this simulation model, bariatric surgery may lead to diabetes remission and reductions in other risk factors, which then lead to fewer diabetes complications and increased quality of life (QoL). Surgery is also associated with perioperative mortality and subsequent complications, and patients in remission may relapse to diabetes. We separately estimate the costs, quality-adjusted life-years (QALYs), and cost-effectiveness of gastric bypass surgery relative to usual diabetes care and of gastric banding surgery relative to usual diabetes care. We examine the cost-effectiveness of each type of surgery for severely obese individuals who are newly diagnosed with diabetes and for severely obese individuals with established diabetes. RESULTS: In all analyses, bariatric surgery increased QALYs and increased costs. Bypass surgery had cost-effectiveness ratios of $7,000/QALY and $12,000/QALY for severely obese patients with newly diagnosed and established diabetes, respectively. Banding surgery had cost-effectiveness ratios of $11,000/QALY and $13,000/QALY for the respective groups. In sensitivity analyses, the cost-effectiveness ratios were most affected by assumptions about the direct gain in QoL from BMI loss following surgery. CONCLUSIONS: Our analysis indicates that gastric bypass and gastric banding are cost-effective methods of reducing mortality and diabetes complications in severely obese adults with diabetes.

A health policy model of CKD: 2. The cost-effectiveness of microalbuminuria screening.

BACKGROUND: Microalbuminuria screening may detect chronic kidney disease in its early stages, allowing for treatment that delays or prevents disease progression. The cost-effectiveness of microalbuminuria screening has not been determined. STUDY DESIGN: A cost-effectiveness model simulating disease progression and costs. SETTING & POPULATION: US patients. MODEL, PERSPECTIVE, AND TIMEFRAME: The microsimulation model follows up disease progression and costs in a cohort of simulated patients from age 50 to 90 years or death. Costs are evaluated from the health care system perspective. INTERVENTION: Microalbuminuria screening at 1-, 2-, 5-, or 10-year intervals followed by treatment with angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers. We considered universal screening, as well as screening targeted at persons with diabetes, persons with hypertension but no diabetes, and persons with neither diabetes nor hypertension. OUTCOMES: Costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios. RESULTS: For the full model population, universal screening increases costs and increases QALYs. Universal annual screening starting at age 50 years has a cost-effectiveness ratio of $73,000/QALY relative to no screening and $145,000/QALY relative to usual care. Cost-effectiveness ratios improved with longer screening intervals. Relative to no screening, targeted annual screening has cost-effectiveness ratios of $21,000/QALY, $55,000/QALY, and $155,000/QALY for persons with diabetes, those with hypertension, and those with neither current diabetes nor current hypertension, respectively. LIMITATIONS: Results necessarily are based on a microsimulation model because of the long time horizon appropriate for chronic kidney disease. The model includes only health care costs. CONCLUSIONS: Microalbuminuria screening is cost-effective for patients with diabetes or hypertension, but is not cost-effective for patients with neither diabetes nor hypertension unless screening is conducted at longer intervals or as part of existing physician visits.

A health policy model of CKD: 1. Model construction, assumptions, and validation of health consequences.

BACKGROUND: A cost-effectiveness model that accurately represents disease progression, outcomes, and associated costs is necessary to evaluate the cost-effectiveness of interventions for chronic kidney disease (CKD). STUDY DESIGN: We developed a microsimulation model of the incidence, progression, and treatment of CKD. The model was validated by comparing its predictions with survey and epidemiologic data sources. SETTING & POPULATION: US patients. MODEL, PERSPECTIVE, & TIMEFRAME: The model follows up disease progression in a cohort of simulated patients aged 30 until age 90 years or death. The model consists of 7 mutually exclusive states representing no CKD, 5 stages of CKD, and death. Progression through the stages is governed by a person's glomerular filtration rate and albuminuria status. Diabetes, hypertension, and other risk factors influence CKD and the development of CKD complications in the model. Costs are evaluated from the health care system perspective. INTERVENTION: Usual care, including incidental screening for persons with diabetes or hypertension. OUTCOMES: Progression to CKD stages, complications, and mortality. RESULTS: The model provides reasonably accurate estimates of CKD prevalence by stage. The model predicts that 47.1% of 30-year-olds will develop CKD during their lifetime, with 1.7%, 6.9%, 27.3%, 6.9%, and 4.4% ending at stages 1-5, respectively. Approximately 11% of persons who reach stage 3 will eventually progress to stage 5. The model also predicts that 3.7% of persons will develop end-stage renal disease compared with an estimate of 3.0% based on current end-stage renal disease lifetime incidence. LIMITATIONS: The model synthesizes data from multiple sources rather than a single source and relies on explicit assumptions about progression. The model does not include acute kidney failure. CONCLUSION: The model is well validated and can be used to evaluate the cost-effectiveness of CKD interventions. The model also can be updated as better data for CKD progression become available.