%0 Journal Article %J Journal of the American Geriatrics Society %D 2023 %T Can markers of disease severity improve the predictive power of claims-based multimorbidity indices? %A Rizzo, Anael %A Jing, Bocheng %A Boscardin, W John %A Shah, Sachin J %A Steinman, Michael A %K Hospitalization %K Medicare %K multimorbidity %K Patient Acuity %X

BACKGROUND: Claims-based measures of multimorbidity, which evaluate the presence of a defined list of diseases, are limited in their ability to predict future outcomes. We evaluated whether claims-based markers of disease severity could improve assessments of multimorbid burden.

METHODS: We developed 7 dichotomous markers of disease severity which could be applied to a range of diseases using claims data. These markers were based on the number of disease-associated outpatient visits, emergency department visits, and hospitalizations made by an individual over a defined interval; whether an individual with a given disease had outpatient visits to a specialist who typically treats that disease; and ICD-9 codes which connote more versus less advanced or symptomatic manifestations of a disease. Using Medicare claims linked with Health and Retirement Study data, we tested whether including these markers improved ability to predict ADL decline, IADL decline, hospitalization, and death compared to equivalent models which only included the presence or absence of diseases.

RESULTS: Of 5012 subjects, median age was 76 years and 58% were female. For a majority of diseases tested individually, adding each of the 7 severity markers yielded minimal increase in c-statistic (≤0.002) for outcomes of ADL decline and mortality compared to models considering only the presence versus absence of disease. Gains in predictive power were more substantial for a small number of individual diseases. Inclusion of the most promising marker in multi-disease multimorbidity indices yielded minimal gains in c-statistics (<0.001-0.007) for predicting ADL decline, IADL decline, hospitalization, and death compared to indices without these markers.

CONCLUSIONS: Claims-based markers of disease severity did not contribute meaningfully to the ability of multimorbidity indices to predict ADL decline, mortality, and other important outcomes.

%B Journal of the American Geriatrics Society %V 71 %P 845-857 %G eng %N 3 %R 10.1111/jgs.18150 %0 Journal Article %J The Journal of Gerontology: Series B %D 2021 %T Changes in Health Care Access and Utilization for Low-SES Adults Age 51-64 after Medicaid Expansion. %A Tipirneni, Renuka %A Helen G Levy %A Kenneth M. Langa %A Ryan J McCammon %A Zivin, Kara %A Jamie E Luster %A Karmakar, Monita %A John Z. Ayanian %K Affordable Care Act %K Hospitalization %K Medicaid %K Retirement %X

OBJECTIVES: Whether the Affordable Care Act (ACA) insurance expansions improved access to care and health for adults age 51-64 has not been closely examined. This study examined longitudinal changes in access, utilization, and health for low-socioeconomic status adults age 51-64 before and after the ACA Medicaid expansion.

METHODS: Longitudinal difference-in-differences (DID) study before (2010-2014) and after (2016) Medicaid expansion, including N=2,088 noninstitutionalized low-education adults age 51-64 (N=633 in Medicaid expansion states, N=1,455 in non-expansion states) from the nationally representative biennial Health and Retirement Study. Outcomes included coverage (any, Medicaid, private), access (usual source of care, difficulty finding doctor, foregone care, cost-related medication nonadherence, out-of-pocket costs), utilization (outpatient visit, hospitalization), and health status.

RESULTS: Low-education adults age 51-64 had increased rates of Medicaid coverage (+10.6 percentage points [pp] in expansion states, +3.2 pp in non-expansion states, DID +7.4 pp, p=0.001) and increased likelihood of hospitalizations (+9.2 pp in expansion states, -1.1 pp in non-expansion states, DID +10.4 pp, p=0.003) in Medicaid expansion compared with non-expansion states after 2014. Those in expansion states also had a smaller increase in limitations in paid work/housework over time, compared to those in non-expansion states (+3.6 pp in expansion states, +11.0 pp in non-expansion states, DID -7.5 pp, p=0.006). There were no other significant differences in access, utilization or health trends between expansion and non-expansion states.

DISCUSSION: After Medicaid expansion, low-education status adults age 51-64 were more likely to be hospitalized, suggesting poor baseline access to chronic disease management and pent-up demand for hospital services.

%B The Journal of Gerontology: Series B %V 76 %P 1218-1230 %G eng %N 6 %R 10.1093/geronb/gbaa123 %0 Journal Article %J J Gerontol B Psychol Sci Soc Sci %D 2003 %T Cognitive function and acute care utilization. %A Walsh, Edith G. %A Bei Wu %A Mitchell, Janet B. %A Lisa F Berkman %K Aged %K Cognition Disorders %K Female %K Geriatric Assessment %K Health Behavior %K Health Status %K Hospitalization %K Hospitals %K Humans %K Length of Stay %K Male %K Neuropsychological tests %K Outpatient Clinics, Hospital %K Severity of Illness Index %K United States %X

OBJECTIVES: Little is known about variation in cognitive function across the aged population, or how use and costs of health care vary with cognitive impairment. This study was designed to create a typology of cognitive function in a nationally representative sample, and evaluate acute care use in relation to cognitive function, holding constant confounding factors. By including proxy assessments of cognitive function, this is the first study to include individuals unable to respond themselves.

METHODS: We analyzed the baseline year of the Asset and Health Dynamics Among the Oldest Old (AHEAD) survey, sponsored by the National Institute on Aging, to create three levels of cognitive function, using direct measures for self-respondents (n = 6,651) and proxy evaluations for the others (n = 792). We used a two-part model to predict the likelihood of using various health services and to evaluate intensity of care among users.

RESULTS: Sixteen percent, 64%, and 20% of the sample fell into the low, moderate, and high cognitive function groups, respectively, that differed significantly on almost all demographic and health status measures, and some utilization measures. Controlling for other health and functional status measures, lower cognitive function had a significant and negative effect on outpatient services, but did not affect hospital use directly.

DISCUSSION: Lower cognitive function may be a barrier to outpatient care, but these analyses should be repeated using administrative use and cost data.

%B J Gerontol B Psychol Sci Soc Sci %I 58B %V 58 %P S38-49 %8 2003 Jan %G eng %N 1 %L pubs_2003_Walsh_etal.pdf %1 http://www.ncbi.nlm.nih.gov/pubmed/12496307?dopt=Abstract %4 Cognitive Function/Health Care Utilization %$ 13572 %R 10.1093/geronb/58.1.s38