Multimorbidity, Mental Illness, and Quality of Care: Preventable Hospitalizations among Medicare Beneficiaries

Providing family planning counseling services for women with chronic medical conditions in an inpatient setting: A randomized feasibility trial

OBJECTIVES

This study aimed to evaluate the feasibility and effectiveness of providing bedside family planning services to women with chronic medical conditions in the inpatient setting.

STUDY DESIGN

We initiated a parallel randomized controlled trial of patients listed as female aged 18 to 44 years who were admitted to the hospital from February 2018 to May 2021 with at least one chronic medical condition associated with lower rates of contraception usage and no documentation of contraception. Patients who confirmed they were not using contraception were enrolled and randomized to one of the three arms. They received bedside family planning counseling and an offer of contraception prior to discharge (oral contraceptive pills, etonogestrel implant, or medroxyprogesterone injection), received a flyer recommending they talk with their outpatient physician about contraception, or received standard care. The primary outcomes were contraception use at 3 months and 12 months after discharge.

RESULTS

Altogether 76 subjects were enrolled and randomized with 22 in the counseling arm and 27 each in the other arms. In the counseling arm, five (23%; 95% CI: 8.0%-45%) elected to receive contraception prior to discharge. Inferential statistics at follow-up were not able to be calculated due to high attrition.

CONCLUSIONS

Providing counseling and offering immediate contraception initiation in the inpatient setting may be a feasible approach to improving contraception access for this population. Additional investigation into the acceptability, efficacy, and generalizability of this approach is warranted.

IMPLICATIONS

Utilizing the inpatient setting may be a feasible approach for delivering contraception counseling to women with chronic medical conditions. This approach merits further study for effectiveness and acceptability. This study highlights the need for contraceptive counseling and initiation to become a standard part of hospital care for pregnancy-capable individuals.

Defining Multimorbidity in Older Patients Hospitalized with Medical Conditions

BACKGROUND

The term "multimorbidity" identifies high-risk, complex patients and is conventionally defined as ≥2 comorbidities. However, this labels almost all older patients as multimorbid, making this definition less useful for physicians, hospitals, and policymakers.

OBJECTIVE

Develop new medical condition-specific multimorbidity definitions for patients admitted with acute myocardial infarction (AMI), heart failure (HF), and pneumonia patients. We developed three medical condition-specific multimorbidity definitions as the presence of single, double, or triple combinations of comorbidities - called Qualifying Comorbidity Sets (QCSs) - associated with at least doubling the risk of 30-day mortality for AMI and pneumonia, or one-and-a-half times for HF patients, compared to typical patients with these conditions.

DESIGN

Cohort-based matching study PARTICIPANTS: One hundred percent Medicare Fee-for-Service beneficiaries with inpatient admissions between 2016 and 2019 for AMI, HF, and pneumonia.

MAIN MEASURES

Thirty-day all-location mortality KEY RESULTS: We defined multimorbidity as the presence of ≥1 QCS. The new definitions labeled fewer patients as multimorbid with a much higher risk of death compared to the conventional definition (≥2 comorbidities). The proportions of patients labeled as multimorbid using the new definition versus the conventional definition were: for AMI 47% versus 87% (p value<0.0001), HF 53% versus 98% (p value<0.0001), and pneumonia 57% versus 91% (p value<0.0001). Thirty-day mortality was higher among patients with ≥1 QCS compared to ≥2 comorbidities: for AMI 15.0% versus 9.5% (p<0.0001), HF 9.9% versus 7.0% (p <0.0001), and pneumonia 18.4% versus 13.2% (p <0.0001).

CONCLUSION

The presence of ≥2 comorbidities identified almost all patients as multimorbid. In contrast, our new QCS-based definitions selected more specific combinations of comorbidities associated with substantial excess risk in older patients admitted for AMI, HF, and pneumonia. Thus, our new definitions offer a better approach to identifying multimorbid patients, allowing physicians, hospitals, and policymakers to more effectively use such information to consider focused interventions for these vulnerable patients.

Physical and psychiatric comorbidities among patients with severe mental illness as seen in Uganda

While psychiatric and physical comorbidities in severe mental illness (SMI) have been associated with increased mortality and poor clinical outcomes, problem has received little attention in low- and middle-income countries (LMICs). This study established the prevalence of psychiatric (schizophrenia, bipolar affective disorder, and recurrent major depressive disorder) and physical (HIV/AIDS, syphilis, hypertension and obesity) comorbidities and associated factors among 1201 out-patients with SMI (schizophrenia, depression and bipolar affective disorder) attending care at two hospitals in Uganda. Participants completed an assessment battery including structured, standardised and locally translated instruments. SMIs were established using the MINI International Neuropsychiatric Interview version 7.2. We used logistic regression to determine the association between physical and psychiatric comorbidities and potential risk factors. Bipolar affective disorder was the most prevalent (66.4%) psychiatric diagnoses followed by schizophrenia (26.6%) and recurrent major depressive disorder (7.0%). Prevalence of psychiatric comorbidity was 9.1%, while physical disorder comorbidity was 42.6%. Specific comorbid physical disorders were hypertension (27.1%), obesity (13.8%), HIV/AIDS (8.2%) and syphilis (4.8%). Potentially modifiable factors independently significantly associated with psychiatric and physical comorbidities were: use of alcohol for both syphilis and hypertension comorbidities; and use of a mood stabilisers and khat in comorbidity with obesity. Only psychiatric comorbidity was positively associated with the negative outcomes of suicidality and risky sexual behaviour. The healthcare models for psychiatric care in LMICs such as Uganda should be optimised to address the high burden of psychiatric and physical comorbidities.

Incipient dementia and avoidable hospital admission in persons with osteoarthritis

Objective

To investigate the associations between incipient dementia (ID) and hospitalization for ambulatory care sensitive conditions (ACSCs) among people with osteoarthritis (OA) of the peripheral joints.

Methods

Among individuals aged 51-99 years residing in Skåne, Sweden, in 2009, we identified those with a doctor-diagnosed OA and no dementia during 1998-2009 (n ​= ​57,733). Treating ID as a time-varying exposure, we followed people from January 1, 2010 or their 60th birthday (whichever occurred last) until hospitalization for ACSCs, death, 100th birthday, relocation outside Skåne, or December 31, 2019 (whichever occurred first). Using age as time scale, we applied flexible parametric survival models, adjusted for confounders, to assess the associations between ID and hospitalization for ACSCs.

Results

There were 58 and 33 hospitalizations for ACSCs per 1000 person-years among OA people with and without ID, respectively. The association between ID and hospitalization for any ACSCs was age-dependent with higher risk in ages<86 years and lower risks in older ages. Between ages 60 and 100 years, persons with ID had, on average, 5.8 (95% CI 0.9, 10.7), 1.6 (-2.6, 5.9) and 3.1 (2.3, 4.0) fewer hospital-free years for any, chronic and acute ACSCs, respectively, compared with persons without ID.

Conclusions

Among persons with OA, while ID was associated with increased risks of hospitalization for ACSCs in younger ages, it was associated with decreased risk in oldest ages. These results suggest the need for improvement in quality of ambulatory care including the continuity of care for people with OA having dementia.

Quality Indicators for High-Need Patients: a Systematic Review

BACKGROUND

Healthcare systems are increasingly implementing programs for high-need patients, who often have multiple chronic conditions and complex social situations. Little, however, is known about quality indicators that might guide healthcare organizations and providers in improving care for high-need patients. We sought to conduct a systematic review to identify potential quality indicators for high-need patients.

METHODS

This systematic review (CRD42020215917) searched PubMed, CINAHL, and EMBASE; guideline clearing houses ECRI and GIN; and Google scholar. We included publications suggesting, evaluating, and utilizing indicators to assess quality of care for high-need patients. Critical appraisal of the indicators addressed the development process, endorsement and adoption, and characteristics, such as feasibility. We standardized indicators by patient population subgroups to facilitate comparisons across different indicator groups.

RESULTS

The search identified 6964 citations. Of these, 1382 publications were obtained as full text, and 53 studies met inclusion criteria. We identified over 1700 quality indicators across studies. Quality indicator characteristics varied widely. The scope of the selected indicators ranged from detailed criterion (e.g., "annual eye exam") to very broad categories (e.g., "care coordination"). Some publications suggested disease condition-specific indicators (e.g., diabetes), some used condition-independent criteria (e.g., "documentation of the medication list in the medical record available to all care agencies"), and some publications used a mixture of indicator types.

DISCUSSION

We identified and evaluated existing quality indicators for a complex, heterogeneous patient group. Although some quality indicators were not disease-specific, we found very few that accounted for social determinants of health and behavioral factors. More research is needed to develop quality indicators that address patient risk factors.

The importance of chronic conditions for potentially avoidable hospitalizations among non-Hispanic Black and non-Hispanic White older adults in the US: a cross-sectional observational study

Background

Non-Hispanic (NH) Black older adults experience substantially higher rates of potentially avoidable hospitalization compared to NH White older adults. This study explores the top three chronic conditions preceding hospitalization and potentially avoidable hospitalization among NH White and NH Black Medicare beneficiaries in the United States.

Methods

Data on 4993 individuals (4,420 NH White and 573 NH Black individuals) aged ≥ 65 years from 2014 Medicare claims were linked with sociodemographic data from previous rounds of the Health and Retirement Study. Conditional inference random forests were used to rank the importance of chronic conditions in predicting hospitalization and potentially avoidable hospitalization separately for NH White and NH Black beneficiaries. Multivariable logistic regression with the top three chronic diseases for each outcome adjusted for sociodemographic characteristics were conducted to quantify the associations.

Results

In total, 22.1% of NH White and 24.9% of NH Black beneficiaries had at least one hospitalization during 2014. Among those with hospitalization, 21.3% of NH White and 29.6% of NH Black beneficiaries experienced at least one potentially avoidable hospitalization. For hospitalizations, chronic kidney disease, heart failure, and atrial fibrillation were the top three contributors among NH White beneficiaries and acute myocardial infarction, chronic obstructive pulmonary disease (COPD), and chronic kidney disease were the top three contributors among NH Black beneficiaries. These chronic conditions were associated with increased odds of hospitalization for both groups. For potentially avoidable hospitalizations, asthma, COPD, and heart failure were the top three contributors among NH White beneficiaries and fibromyalgia/chronic pain/fatigue, COPD, and asthma were the top three contributors among NH Black beneficiaries. COPD and heart failure were associated with increased odds of potentially avoidable hospitalization among NH White beneficiaries, whereas only COPD was associated with increased odds of potentially avoidable hospitalizations among NH Black beneficiaries.

Conclusion

Having at least one hospitalization and at least one potentially avoidable hospitalization was more prevalent among NH Black than NH White Medicare beneficiaries. This suggests greater opportunity for increasing prevention efforts among NH Black beneficiaries. The importance of COPD for potentially avoidable hospitalizations further highlights the need to focus on prevention of exacerbations for patients with COPD, possibly through greater access to primary care and continuity of care.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-022-07849-y.

Mental Health Conditions and Hospitalizations for Ambulatory Care Sensitive Conditions Among Veterans with Diabetes

BACKGROUND

Veterans with diabetes and mental health conditions have a higher risk for suboptimal care and complications related to their diseases than veterans with diabetes who do not have mental health conditions. We hypothesized that among veterans with diabetes, patients with mental health conditions are more likely to be hospitalized for ambulatory care sensitive conditions (ACSC) than those without mental health conditions.

OBJECTIVES

To examine the association between depression, anxiety, and serious mental illness and hospitalizations for ACSC among veterans with diabetes after controlling for demographics and comorbidities.

METHODS

We used a retrospective cohort design with merged Veterans Health Administration (VHA) and Medicare electronic health records from 2008 to 2010. Andersen's Behavioral Model of Health Services Use was used to select the variables associated with hospitalizations for ACSC (ie, predisposing, enabling and need characteristics, personal health practices, and external environment). We used chi-square tests and logistic regressions for our analyses.

RESULTS

Among the dual VHA/Medicare-enrolled veterans with any hospitalization in 2010, 30% had hospitalizations for ACSC. Veterans with diabetes and co-occurring depression were at increased likelihood to be hospitalized for ACSC, after adjusting for all other covariates (adjusted odds ratio, 1.08; 95% confidence interval, 1.04-1.11). Similar findings were observed for anxiety. Veterans with serious mental illness were as likely as veterans without serious mental illness to be hospitalized for ACSC.

CONCLUSION

Veterans with depression and anxiety were more likely to be hospitalized for any or acute ACSC than veterans without mental health conditions. Patients hospitalized for acute ACSC were more susceptible than patients hospitalized for chronic ACSC to have mental health conditions. As the VHA continues to evolve from care provider to community care payer (per the Veterans Affairs MISSION Act), our results highlight the ongoing importance of care coordination and communication between payers and providers.

Potentially Preventable Medical Hospitalizations and Emergency Department Visits by the Behavioral Health Population

This study investigated geographic variation in potentially preventable medical outcomes that might be used to monitor access to high-quality medical care in the behavioral health population. Analyzing public and non-public data sources from California on adults admitted between 2009 and 2011 to all non-federal licensed medical inpatient (N = 6,603,146) or emergency department units (N = 21,011,958) revealed that 33.6% of nearly 1 million potentially preventable hospitalizations and 9.8% of 1.5 million potentially preventable emergency department visits were made by people with mental or substance use disorder diagnoses. Across California counties or county groups (N = 36), a higher preventable hospitalization rate in the behavioral health population was associated with higher poverty, higher primary care safety net utilization, and fewer mental health providers. Although further validation is required, rates of potentially preventable encounters, particularly hospitalizations, may be useful measures of access to high-quality care in the behavioral health population.

Defining Multimorbidity in Older Surgical Patients

BACKGROUND

There are numerous definitions of multimorbidity (MM). None systematically examines specific comorbidity combinations accounting for multiple testing when exploring large datasets.

OBJECTIVES

Develop and validate a list of all single, double, and triple comorbidity combinations, with each individual qualifying comorbidity set (QCS) more than doubling the odds of mortality versus its reference population. Patients with at least 1 QCS were defined as having MM.

RESEARCH DESIGN

Cohort-based study with a matching validation study.

SUBJECTS

All fee-for-service Medicare patients between age 65 and 85 without dementia or metastatic solid tumors undergoing general surgery in 2009-2010, and an additional 2011-2013 dataset.

MEASURES

30-day all-location mortality.

RESULTS

There were 576 QCSs (2 singles, 63 doubles, and 511 triples), each set more than doubling the odds of dying. In 2011, 36% of eligible patients had MM. As a group, multimorbid patients (mortality rate=7.0%) had a mortality Mantel-Haenszel odds ratio=1.90 (1.77-2.04) versus a reference that included both multimorbid and nonmultimorbid patients (mortality rate=3.3%), and Mantel-Haenszel odds ratio=3.72 (3.51-3.94) versus only nonmultimorbid patients (mortality rate=1.6%). When matching 3151 pairs of multimorbid patients from low-volume hospitals to similar patients in high-volume hospitals, the mortality rates were 6.7% versus 5.2%, respectively (P=0.006).

CONCLUSIONS

A list of QCSs identified a third of older patients undergoing general surgery that had greatly elevated mortality. These sets can be used to identify vulnerable patients and the specific combinations of comorbidities that make them susceptible to poor outcomes.

Type of Multimorbidity and Patient-Doctor Communication and Trust among Elderly Medicare Beneficiaries

Background. Effective communication and high trust with doctor are important to reduce the burden of multimorbidity in the rapidly aging population of the US. However, the association of multimorbidity with patient-doctor communication and trust is unknown. Objective. We examined the relationship between multimorbidity and patient-doctor communication and trust among the elderly. Method. We used the Medicare Current Beneficiary Survey (2012) to analyze the association between multimorbidity and patient-doctor communication and trust with multivariable logistic regressions that controlled for patient's sociodemographic characteristics, health status, and satisfaction with care. Results. Most elderly beneficiaries reported effective communication (87.5-97.5%) and high trust (95.4-99.1%) with their doctors. The elderly with chronic physical and mental conditions were less likely than those with only physical conditions to report effective communication with their doctor (Adjusted Odds Ratio [95% Confidence Interval] = 0.80 [0.68, 0.96]). Multimorbidity did not have a significant association with patient-doctor trust. Conclusions. Elderly beneficiaries had high trust in their doctors, which was not affected by the presence of multimorbidity. Elderly individuals who had a mental condition in addition to physical conditions were more likely to report ineffective communication. Programs to improve patient-doctor communication with patients having cooccurring chronic physical and mental health conditions may be needed.

The impact of multiple chronic diseases on hospitalizations for ambulatory care sensitive conditions

BACKGROUND

The high financial burden of avoidable hospitalizations has led to an increase of the study of hospitalizations for ambulatory care sensitive conditions (ACSC). There is limited information on the impact of secondary diagnoses on these hospitalizations, although patients' social and demographic characteristics, as well as the coexistence of multiple diseases are often identified in the literature as risk factors for avoidable hospitalizations. This study explores the impact of chronic conditions on the likelihood of hospitalizations for ACSC.

METHODS

Data were extracted from the Portuguese hospital discharge database. Avoidable hospitalizations were identified according to the Canadian Institute for Healthcare Information, and chronic conditions were identified according to criteria set by the Agency for Healthcare Research and Quality. A retrospective study analysing all patients hospitalized for an ACSC and all patients hospitalized for non-ACSC was made, using multiple logistic regression models to identify the impact of chronic conditions on the risk of admission.

RESULTS

The risk of an avoidable hospitalization increases by a factor of 1.35 (95 % CI [1.34;1.35]) for each additional chronic condition, and 1.55 (95 % CI [1.55;1.56]) for each additional body system affected. The respiratory and circulatory systems have the most impact on the risk of ACSC, increasing the risk by 8.72 (95 % CI [8.58;8.86]) and 3.01 (95 % CI [2.95;3.06]), respectively.

CONCLUSIONS

The number of chronic conditions and the body systems affected increase the risk of hospital admissions for ACSC.

Ambulatory Care Sensitive Hospitalizations among Medicaid Beneficiaries with Chronic Conditions

OBJECTIVES

This study examined the relationship between ambulatory care sensitive hospitalizations (ACSH) and patient-level and county-level variables.

METHODS

Utilizing a retrospective cohort approach, multi-state Medicaid claims data from 2007-2008 was used to examine ACSH at baseline and follow-up periods. The study cohort consisted of adult, non-elderly Medicaid beneficiaries with chronic physical conditions, who were continuously enrolled in fee-for-service programs, not enrolled in Medicare, and did not die during the study period (N=7,021). The dependent variable, ACSH, was calculated in the follow-up year using an algorithm from the Agency for Healthcare Research and Quality algorithm. Patient-level (demographic, health status, continuity of care) and county-level (density of healthcare providers and facilities, socio-economic characteristics, local economic conditions) factors were included as independent variables. Multivariable logistic regression models were used to examine the relationship between ACSH and independent variables.

RESULTS

In this study population, 8.2% had an ACSH. African-Americans were more likely to have an ACSH [AOR=1.55, 95% CI 1.16, 2.07] than Caucasians. Adults with schizophrenia were more likely to have an ACSH, compared to those without schizophrenia [AOR=1.54, 95% CI 1.16, 2.04]. Residents in counties with a higher number of community mental health centers [AOR=0.88, 95% CI 0.80, 0.97] and rural health centers [AOR=0.98, 95% CI 0.95, 0.99] were less likely to have an ASCH.

CONCLUSIONS

Programs and interventions designed to reduce the risk of ACSH may be needed to target specific population subgroups and improve healthcare infrastructure.

Multiple chronic conditions and healthcare costs among adults

The prevalence of multiple chronic conditions (MCC) is increasing among individuals of all ages. MCC are associated with poor health outcomes. The presence of MCC has profound healthcare utilization and cost implications for public and private insurance payers, individuals, and families. Investigators have used a variety of definitions for MCC to evaluate costs associated with MCC. The objective of this article is to examine the current literature in estimating excess costs associated with MCC among adults. The discussion highlights some of the theoretical and technical merits of various MCC definitions and models used to estimate the excess costs associated with MCC.

Type of Multimorbidity and Complementary and Alternative Medicine Use among Adults

Objective. To examine the association between type of multimorbidity and CAM use among adults with multimorbidity. Methods. The current study used a cross-sectional design with retrospective data from 2012 National Health Interview Survey. Multimorbidity was classified into two groups: (1) adults with coexisting physical and mental illnesses and (2) adults with two or more chronic physical illnesses only. CAM use was measured using a set of 18 variables. Logistic regression and multinomial logistic regressions were used to assess the association between the type of multimorbidity and ever used CAM, CAM use in the past 12 months, and type of CAM. Results. Overall, 31.2% of adults with coexisting physical and mental illnesses and 20.1% of adults with only physical illnesses used CAM in the past 12 months. Adults with coexisting physical and mental illnesses were more likely to ever use CAM (AOR = 1.68, 95% CI = 1.49, 1.90), use CAM in the past 12 months (AOR = 1.32, 95% CI = 1.15, 1.52), and use mind-body therapies in the past 12 months (AOR = 1.36, 95% CI = 1.16, 1.59) compared to adults with only physical illnesses. Conclusion. Multimorbidity of chronic physical and mental illnesses was associated with higher CAM use.

Explaining the increased health care expenditures associated with gastroesophageal reflux disease among elderly Medicare beneficiaries with chronic obstructive pulmonary disease: a cost-decomposition analysis

OBJECTIVE

To estimate excess health care expenditures associated with gastroesophageal reflux disease (GERD) among elderly individuals with chronic obstructive pulmonary disease (COPD) and examine the contribution of predisposing characteristics, enabling resources, need variables, personal health care practices, and external environment factors to the excess expenditures, using the Blinder-Oaxaca linear decomposition technique.

METHODS

This study utilized a cross-sectional, retrospective study design, using data from multiple years (2006-2009) of the Medicare Current Beneficiary Survey linked with fee-for-service Medicare claims. Presence of COPD and GERD was identified using diagnoses codes. Health care expenditures consisted of inpatient, outpatient, prescription drugs, dental, medical provider, and other services. For the analysis, t-tests were used to examine unadjusted subgroup differences in average health care expenditures by the presence of GERD. Ordinary least squares regressions on log-transformed health care expenditures were conducted to estimate the excess health care expenditures associated with GERD. The Blinder-Oaxaca linear decomposition technique was used to determine the contribution of predisposing characteristics, enabling resources, need variables, personal health care practices, and external environment factors, to excess health care expenditures associated with GERD.

RESULTS

Among elderly Medicare beneficiaries with COPD, 29.3% had co-occurring GERD. Elderly Medicare beneficiaries with COPD/GERD had 1.5 times higher ($36,793 vs $24,722 [P<0.001]) expenditures than did those with COPD/no GERD. Ordinary least squares regression revealed that individuals with COPD/GERD had 36.3% (P<0.001) higher expenditures than did those with COPD/no GERD. Overall, 30.9% to 43.6% of the differences in average health care expenditures were explained by differences in predisposing characteristics, enabling resources, need variables, personal health care practices, and external environment factors between the two groups. Need factors explained up to 41% of the differences in average health care expenditures between the two groups.

CONCLUSION

Among elderly Medicare beneficiaries with COPD, the presence of GERD was associated with higher expenditures. Need factors primarily contributed to the differences in average health care expenditures, suggesting that the comanagement of chronic conditions may reduce excess health care expenditures associated with GERD.

Depression and ambulatory care sensitive hospitalizations among Medicare beneficiaries with chronic physical conditions

OBJECTIVE

We examined the association between depression and hospitalizations for Ambulatory Care Sensitive Conditions (H-ACSC) among Medicare beneficiaries with chronic physical conditions.

METHODS

We used a retrospective longitudinal design using multiple years (2002-2009) of linked fee-for-service Medicare claims and survey data from Medicare Current Beneficiary Survey to create six longitudinal panels. We followed individuals in each panel for a period of 3-years; first year served as the baseline and subsequent 2-years served as the follow-up. We measured depression, chronic physical conditions and other characteristics at baseline and examined H-ACSC at follow-up. We identified chronic physical conditions from survey data and H-ACSC and depression from fee-for-service Medicare claims. We analyzed unadjusted and adjusted relationships between depression and the risk of H-ACSC with chi-square tests and logistic regressions.

RESULTS

Among all Medicare beneficiaries, 9.3% had diagnosed depression. Medicare beneficiaries with depression had higher rates of any H-ACSC as compared to those without depression (13.6% vs. 7.7%). Multivariable regression indicated that, compared to those without depression, Medicare beneficiaries with depression were more likely to experience any H-ACSC.

CONCLUSIONS

Depression was associated with greater risk of H-ACSC, suggesting that health care quality measures may need to include depression as a risk-adjustment variable.

Research priorities in geriatric palliative care: multimorbidity

With global aging and scientific advances extending survival, the number of adults experiencing multiple chronic conditions has grown substantially and is projected to increase by another third between 2000 and 2030. Among the many challenges posed by multimorbidity, some of the most pressing include how to characterize and measure comorbid conditions, understand symptoms and illness burden, and provide person-centered care in the context of competing health care priorities and increasing complexity. In this white paper emanating from a National Institute on Aging supported conference to discuss research gaps at the geriatrics-palliative care interface, the authors review common definitions of multimorbidity; describe the association between multimorbidity and quality of life, functional status, quality of care, and health care utilization; note content and methodological gaps in multimorbidity evidence; and make recommendations regarding research priorities in this area of expanding public health impact.