The Construction of a Multidomain Risk Model of Alzheimer's Disease and Related Dementias.

BACKGROUND: Alzheimer's disease (AD) and related dementia (ADRD) risk is affected by multiple dependent risk factors; however, there is no consensus about their relative impact in the development of these disorders. OBJECTIVE: To rank the effects of potentially dependent risk factors and identify an optimal parsimonious set of measures for predicting AD/ADRD risk from a larger pool of potentially correlated predictors. METHODS: We used diagnosis record, survey, and genetic data from the Health and Retirement Study to assess the relative predictive strength of AD/ADRD risk factors spanning several domains: comorbidities, demographics/socioeconomics, health-related behavior, genetics, and environmental exposure. A modified stepwise-AIC-best-subset blanket algorithm was then used to select an optimal set of predictors. RESULTS: The final predictive model was reduced to 10 features for AD and 19 for ADRD; concordance statistics were about 0.85 for one-year and 0.70 for ten-year follow-up. Depression, arterial hypertension, traumatic brain injury, cerebrovascular diseases, and the APOE4 proxy SNP rs769449 had the strongest individual associations with AD/ADRD risk. AD/ADRD risk-related co-morbidities provide predictive power on par with key genetic vulnerabilities. CONCLUSION: Results confirm the consensus that circulatory diseases are the main comorbidities associated with AD/ADRD risk and show that clinical diagnosis records outperform comparable self-reported measures in predicting AD/ADRD risk. Model construction algorithms combined with modern data allows researchers to conserve power (especially in the study of disparities where disadvantaged groups are often grossly underrepresented) while accounting for a high proportion of AD/ADRD-risk-related population heterogeneity stemming from multiple domains.

Expanding the scope of health disparities research in Alzheimer's disease and related dementias: Recommendations from the "Leveraging Existing Data and Analytic Methods for Health Disparities Research Related to Aging and Alzheimer's Disease and Related Dementias" Workshop Series.

Topics discussed at the "Leveraging Existing Data and Analytic Methods for Health Disparities Research Related to Aging and Alzheimer's Disease and Related Dementias" workshop, held by Duke University and the Alzheimer's Association with support from the National Institute on Aging, are summarized.  Ways in which existing data resources paired with innovative applications of both novel and well-known methodologies can be used to identify the effects of multi-level societal, community, and individual determinants of race/ethnicity, sex, and geography-related health disparities in Alzheimer's disease and related dementia are proposed.  Current literature on the population analyses of these health disparities is summarized with a focus on identifying existing gaps in knowledge, and ways to mitigate these gaps using data/method combinations are discussed at the workshop.  Substantive and methodological directions of future research capable of advancing health disparities research related to aging are formulated.

Optogenetic and chemogenetic manipulation of seizure threshold in mice.

Here, we present a protocol using optogenetics or chemogenetics to assess the neuronal circuits contributing to seizure initiation. Both approaches allow for targeted control of neuronal populations in vivo and can be combined with experimental manipulations to acutely induce seizures in rodent models. We describe how to (1) introduce and (2) activate optogenetic or chemogenetic actuators while (3) inducing seizures via hyperthermia in a mouse model of epilepsy. This protocol can be adapted for use in other induced seizure models. For complete details on the use and execution of this protocol, please refer to Mattis et al. (2022).1.

Epidemiology of geographic disparities in heart failure among US older adults: a Medicare-based analysis.

BACKGROUND: There are prominent geographic disparities in the life expectancy (LE) of older US adults between the states with the highest (leading states) and lowest (lagging states) LE and their causes remain poorly understood. Heart failure (HF) has been proposed as a major contributor to these disparities. This study aims to investigate geographic disparities in HF outcomes between the leading and lagging states. METHODS: The study was a secondary data analysis of HF outcomes in older US adults aged 65+, using Center for Disease Control and Prevention sponsored Wide-Ranging Online Data for Epidemiologic Research (CDC WONDER) database and a nationally representative 5% sample of Medicare beneficiaries over 2000-2017. Empiric estimates of death certificate-based mortality from HF as underlying cause of death (CBM-UCD)/multiple cause of death (CBM-MCD); HF incidence-based mortality (IBM); HF incidence, prevalence, and survival were compared between the leading and lagging states. Cox regression was used to investigate the effect of residence in the lagging states on HF incidence and survival. RESULTS: Between 2000 and 2017, HF mortality rates (per 100,000) were higher in the lagging states (CBM-UCD: 188.5-248.6; CBM-MCD: 749.4-965.9; IBM: 2656.0-2978.4) than that in the leading states (CBM-UCD: 79.4-95.6; CBM-MCD: 441.4-574.1; IBM: 1839.5-2138.1). Compared to their leading counterparts, lagging states had higher HF incidence (2.9-3.9% vs. 2.2-2.9%), prevalence (15.6-17.2% vs. 11.3-13.0%), and pre-existing prevalence at age 65 (5.3-7.3% vs. 2.8-4.1%). The most recent rates of one- (77.1% vs. 80.4%), three- (59.0% vs. 60.7%) and five-year (45.8% vs. 49.8%) survival were lower in the lagging states. A greater risk of HF incidence (Adjusted Hazards Ratio, AHR [95%CI]: 1.29 [1.29-1.30]) and death after HF diagnosis (AHR: 1.12 [1.11-1.13]) was observed for populations in the lagging states. The study also observed recent increases in CBMs and HF incidence, and declines in HF prevalence, prevalence at age 65 and survival with a decade-long plateau stage in IBM in both leading and lagging states. CONCLUSION: There are substantial geographic disparities in HF mortality, incidence, prevalence, and survival across the U.S.: HF incidence, prevalence at age 65 (age of Medicare enrollment), and survival of patients with HF contributed most to these disparities. The geographic disparities and the recent increase in incidence and decline in survival underscore the importance of HF prevention strategies.

Vulnerability to Hypertension Is a Major Determinant of Racial Disparities in Alzheimer's Disease Risk.

BACKGROUND: Higher incidence levels of Alzheimer's disease (AD) in Black Americans are well documented. However, quantitative explanations of this disparity in terms of risk-factor diseases acting through well-defined pathways are lacking. METHODS: We applied a Blinder-Oaxaca-based algorithm modified for censored data to a 5% random sample of Medicare beneficiaries age 65+ to explain Black/White disparities in AD risk in terms of differences in exposure and vulnerability to morbidity profiles based on 10 major AD-risk-related diseases. RESULTS: The primary contribution to racial disparities in AD risk comes from morbidity profiles that included hypertension with about 1/5th of their contribution due to differences in prevalence (exposure effect) and 4/5ths to differences in the effects of the morbidity profile on AD risk (vulnerability effect). In total, disease-related effects explained a higher proportion of AD incidence in Black Americans than in their White counterparts. CONCLUSIONS: Disease-related causes may represent some of the most straightforward targets for targeted interventions aimed at the reduction of racial disparities in health among US older adults. Hypertension is a manageable and potentially preventable condition responsible for the majority of the Black/White differences in AD risk, making mitigation of the role of this disease in engendering higher AD incidence in Black Americans a prominent concern.

Extended anesthesia exposure for abdominal and pelvic procedures in older adults with colorectal cancer: Associations with chart dementia diagnoses.

BACKGROUND: We hypothesized that cumulative anesthesia exposure over the course of routine treatment of colorectal cancer in older adults can increase long-term risk of Alzheimer's disease (AD), Alzheimer's disease-related dementias (ADRD), and other chronic neurocognitive disorders (CND). METHODS: We conducted a SEER-Medicare-based retrospective cohort study of 84,770 individuals age 65 years and older diagnosed with colorectal cancer between 1998 and 2007 using a proportional hazards model with inverse probability weighted estimators. The primary exploratory variable was a time-variant measure of cumulative anesthesia exposure for abdominal and pelvic procedures, updated continuously. RESULTS: Our primary outcomes, AD and ADRD, occurred in 6005/84,770 (7.1%) and 14,414/83,444 (17.3%) individuals respectively. No statistically significant association was found between cumulative anesthesia exposure and AD (hazard ratio [HR], 0.993; 95% CI, 0.973-1.013). However, it was moderately associated with the risk of ADRD (HR, 1.016; 95% CI, 1.004-1.029) and some secondary outcomes including most notably: cerebral degeneration (HR, 1.048; 95% CI, 1.033-1.063), hepatic encephalopathy (HR, 1.133; 95% CI, 1.101-1.167), encephalopathy-not elsewhere classified (HR,1.095; 95% CI: 1.076-1.115), and incident/perioperative delirium (HR, 1.022; 95% CI, 1.012-1.032). Furthermore, we observed an association between perioperative delirium and increased risk of AD (HR, 2.05; 95% CI, 1.92-2.09). CONCLUSION: Cumulative anesthesia exposure for abdominal and pelvic procedures was not associated with increased risk of AD directly and had a small but statistically significant association with ADRD and a number of other CNDs. Cumulative anesthesia exposure was also associated with perioperative delirium, which had an independent adverse association with AD risk.

Epidemiology of Geographic Disparities of Myocardial Infarction Among Older Adults in the United States: Analysis of 2000-2017 Medicare Data.

Background: There are substantial geographic disparities in the life expectancy (LE) across the U.S. with myocardial infarction (MI) contributing significantly to the differences between the states with highest (leading) and lowest (lagging) LE. This study aimed to systematically investigate the epidemiology of geographic disparities in MI among older adults. Methods: Data on MI outcomes among adults aged 65+ were derived from the Center for Disease Control and Prevention-sponsored Wide-Ranging Online Data for Epidemiologic Research database and a 5% sample of Medicare Beneficiaries for 2000-2017. Death certificate-based mortality from MI as underlying/multiple cause of death (CBM-UCD/CBM-MCD), incidence-based mortality (IBM), incidence, prevalence, prevalence at age 65, and 1-, 3-, and 5-year survival, and remaining LE at age 65 were estimated and compared between the leading and lagging states. Cox model was used to investigate the effect of residence in the lagging states on MI incidence and survival. Results: Between 2000 and 2017, MI mortality was higher in the lagging than in the leading states (per 100,000, CBM-UCD: 236.7-583.7 vs. 128.2-357.6, CBM-MCD: 322.7-707.7 vs. 182.4-437.7, IBM: 1330.5-1518.9 vs. 1003.3-1197.0). Compared to the leading states, lagging states had higher MI incidence (1.1-2.0% vs. 0.9-1.8%), prevalence (10.2-13.1% vs. 8.3-11.9%), pre-existing prevalence (2.5-5.1% vs. 1.4-3.6%), and lower survival (70.4 vs. 77.2% for 1-year, 63.2 vs. 67.2% for 3-year, and 52.1 vs. 58.7% for 5-year), and lower remaining LE at age 65 among MI patients (years, 8.8-10.9 vs. 9.9-12.8). Cox model results showed that the lagging states had greater risk of MI incidence [Adjusted hazards ratio, AHR (95% Confidence Interval, CI): 1.18 (1.16, 1.19)] and death after MI diagnosis [1.22 (1.21, 1.24)]. Study results also showed alarming declines in survival and remaining LE at age 65 among MI patients. Conclusion: There are substantial geographic disparities in MI outcomes, with lagging states having higher MI mortality, incidence, and prevalence, lower survival and remaining LE at age 65. Disparities in MI mortality in a great extent could be due to between-the-state differences in MI incidence, prevalence at age 65 and survival. Observed declines in survival and remaining LE require an urgent analysis of contributing factors that must be addressed.

Exposure to low-dose ambient fine particulate matter PM2.5 and Alzheimer's disease, non-Alzheimer's dementia, and Parkinson's disease in North Carolina.

Alzheimer's disease (AD), non-AD dementia, and Parkinson's disease (PD) are increasingly common in older adults, yet all risk factors for their onset are not fully understood. Consequently, environmental exposures, including air pollution, have been hypothesized to contribute to the etiology of neurodegeneration. Because persistently elevated rates of AD mortality in the southern Piedmont area of North Carolina (NC) have been documented, we studied mortality and hospital admissions for AD, non-AD dementia, and PD in residential populations aged 65+ with long-term exposures to elevated levels of ambient air particulate matter 2.5 (PM2.5) exceeding the World Health Organization (WHO) air quality standards (≥10µg/m3). Health data were obtained from the State Center for Health Statistics and the Healthcare Cost and Utilization Project. PM2.5 levels were obtained from the MODIS/MISR and SeaWiFS datafiles. Residents in the Study group of elevated air particulate matter (87 zip codes with PM2.5≥10µg/m3) were compared to the residents in the Control group with low levels of air particulate matter (81 zip codes with PM2.5≤7.61µg/m3), and were found to have higher age-adjusted rates of mortality and hospital admissions for AD, non-AD dementia, and PD, including a most pronounced increase in AD mortality (323/100,000 vs. 257/100,000, respectively). After adjustment for multiple co-factors, the risk of death (odds ratio, or OR) from AD in the Study group (OR = 1.35, 95%CI[1.24-1.48]) was significantly higher than ORs of non-AD dementia or PD (OR = 0.97, 95%CI[0.90-1.04] and OR = 1.13, 95%CI[0.92-1.31]). The OR of hospital admissions was significantly increased only for AD as a primary case of hospitalization (OR = 1.54, 95%CI[1.31-1.82]). Conclusion: NC residents aged 65+ with long-term exposures to ambient PM2.5 levels exceeding the WHO standard had significantly increased risks of death and hospital admissions for AD. The effects for non-AD dementia and PD were less pronounced.

Analysis of Time Trends in Alzheimer's Disease and Related Dementias Using Partitioning Approach.

BACKGROUND: Understanding the dynamics of epidemiologic trends in Alzheimer's disease (AD) and related dementias (ADRD) and their epidemiologic causes is vital to providing important insights into reducing the burden associated with these conditions. OBJECTIVE: To model the time trends in age-adjusted AD/ADRD prevalence and incidence-based mortality (IBM), and identify the main causes of the changes in these measures over time in terms of interpretable epidemiologic quantities. METHODS: Trend decomposition was applied to a 5%sample of Medicare beneficiaries between 1991 and 2017. RESULTS: Prevalence of AD was increasing between 1992 and 2011 and declining thereafter, while IBM increased over the study period with a significant slowdown in its rate of growth from 2011 onwards. For ADRD, prevalence and IBM increased through 2014 prior to taking a downwards turn. The primary determinant responsible for declines in prevalence and IBM was the deceleration in the increase and eventual decrease in incidence rates though changes in relative survival began to affect the overall trends in prevalence/IBM in a noticeable manner after 2008. Other components showed only minor effects. CONCLUSION: The prevalence and IBM of ADRD is expected to continue to decrease. The directions of these trends for AD are not clear because AD incidence, the main contributing component, is decreasing but at a decreasing rate suggesting a possible reversal. Furthermore, emerging treatments may contribute through their effects on survival. Improving ascertainment of AD played an important role in trends of AD/ADRD over the 1991-2009/10 period but this effect has exhausted itself by 2017.

Geographic disparities in mortality from Alzheimer's disease and related dementias.

OBJECTIVES: The regions with highest and lowest Alzheimer's disease (AD) mortality across the United States at state/county levels were identified and their contribution to the differences in total mortality rates between these regions was evaluated. The disease, disease group, sex, race/ethnicity, and place-of-death-related inter-region differences that engender the disparity in mortality were quantitatively described. The hypothesis that inter-regional differences in filling out death certificates are a major contributor to differences in AD mortality was tested. DESIGN: Retrospective evaluation of death certificate data. SETTING: The United States. PARTICIPANTS: Deceased US residents, 1999-2018. METHODS: Region-specific age-adjusted mortality rates and group-specific rate decomposition. RESULTS: The county clusters with the highest and lowest AD mortality rates were in Washington (WA) and New York (NY), respectively, with other notable high-mortality clusters on the border of Tennessee, Georgia, and Alabama as well as in North Dakota and South Dakota. These patterns were stable over the 1999-2018 period. AD had the highest contribution to total mortality difference between WA and NY (156%, higher in WA), in contrast circulatory diseases had a contribution of comparable magnitude (154%) but were higher in NY. Differences in cause-of-death certificate coding, either through coding of non-AD dementias, or other conditions accompanying a potential AD death could not account for differences in AD mortality between NY and WA. CONCLUSIONS: Inter-regional differences in filling out death certificates were not a major contributor to variation in AD mortality between the regions with the highest and lowest rates. The respective mitigation of the effects of neural and circulatory diseases and several other high-impact conditions would not negate the disparity in mortality between NY and WA.

Chemotherapy and the Risk of Alzheimer's Disease in Colorectal Cancer Survivors: Evidence From the Medicare System.

PURPOSE: Evidence on the nature of the relationship between patients receiving chemotherapy as an essential part of guideline-concordant cancer care and the onset of Alzheimer's Disease (AD) and other adverse cognitive outcomes has been mixed. Biological mechanisms were proposed to support both a potentially beneficial and an adverse role. To explore the relationship between chemotherapy and onset of AD and other neurocognitive disorders (ND) in colorectal cancer survivors. METHODS: We conducted a retrospective cohort study of 135,834 individuals older than 65 years diagnosed with colorectal cancer between 1998 and 2007, using SEER-Medicare data. A proportional hazards model was used before and after the use of inverse probability weighting to account for populational differences between the chemotherapy and nonchemotherapy groups. Weights were normalized to the total sample size. RESULTS: After inverse probability weighting, chemotherapy was associated with decreased AD risk (hazard ratio [HR]: 0.791; 95% CI: 0.758 to 0.824) and lower risk for the majority of other ND including AD-related diseases (HR: 0.823; CI: 0.802 to 0.844), dementia (permanent mental disorder) (HR: 0.807; CI: 0.782 to 0.832), and dementia (senile) (HR: 0.772; CI: 0.745 to 0.801). The only adverse effect to remain significant was cerebral degeneration (excluding AD) (HR: 1.067; CI: 1.033 to 1.102). The effects for AD remained after treatment was stratified by chemotherapy agent type and remained significant for up to 6 years past diagnosis. CONCLUSION: Chemotherapy use in colorectal cancer survivors demonstrated an association with reduced risk for AD and other ND.

Uterine Cancer Mortality in White and African American Females in Southeastern North Carolina.

The residents of southeastern North Carolina (NC) are exposed to multiple socioeconomic and environmental risk factors and have higher mortality rates for a number of diseases. Uterine cancer mortality is known to vary dramatically by race, so we analyzed uterine cancer mortality in populations defined by zip codes in this area to investigate the contributions of various environmental risk factors to race-specific disease patterns. Methods. Zip code specific mortality and hospital admissions for uterine cancer from 2007 to 2013 were analyzed using the NC State Center for Health Statistics data and the Inpatient Database of the Healthcare Cost and Utilization Project datafiles, respectively. Results were adjusted for age, income, education, health insurance coverage, prevalence of current smokers, and density of primary care providers. Results. Uterine cancer mortality rates were generally higher in African American (32.5/100,000, 95% CI = 18.9-46.1) compared to White (19.6/100,000, 95% CI = 12.3-26.9) females. Odds ratios (ORs) of uterine cancer death were higher in White females (OR = 2.27, p < 0.0001) residing within zip codes with hog concentrated animal feeding operations (CAFOs) (hog density >215 hogs/km2) than in White females residing in non-CAFO communities. African American females living near CAFOs had less pronounced increase of uterine cancer death (OR = 1.08, p=0.7657). Conclusion. White females living in adjacent to hog CAFOs areas of southeastern NC have lower rates of mortality from uterine cancer than African American females, but they have higher odds of death compared to their counterparts living in other NC areas. African American females living near CAFOs also have modest increases from their high baseline mortality. While the observed associations do not prove a causation, improving access to screening and medical care is important to mitigate this health issues in southeastern NC.

Partitioning of time trends in prevalence and mortality of lung cancer.

BACKGROUND: Time trends of lung cancer prevalence and mortality are the result of three competing processes: changes in the incidence rate, stage-specific survival, and ascertainment at early stages. Improvements in these measures act concordantly to improve disease-related mortality, but push the prevalence rate in opposite directions making a qualitative interpretation difficult. The goal of this paper is to evaluate the relative contributions of these components to changes in lung cancer prevalence and mortality. METHODS: Partitioning of prevalence and mortality trends into their components using SEER data for 1973-2013. RESULTS: The prevalence of lung cancer increases for females and decreases for males. In 1998, the former was due to increased incidence (45%-50% of total trend), improved survival (40%-45%), and increased ascertainment at early stages (10%-15%). In males, a rapidly declining incidence rate overpowered the effects of survival and ascertainment resulting in an overall decrease in prevalence over time. Trends in lung cancer mortality are determined by incidence during 1993-2002 with noticeable contribution of survival after 2002. CONCLUSION: Lung cancer incidence was the main driving force behind trends in prevalence and mortality. Improved survival played essential role from 2000 onwards. Trends in stage ascertainment played a small but adverse role. Our results suggest that further improvement in lung cancer mortality can be achieved through advances in early stage ascertainment, especially for males, and that in spite of success in treatment, adenocarcinoma continues to exhibit adverse trends (especially in female incidence) and its role among other histology-specific lung cancers will increase in the near future.

Mortality and Health Outcomes in North Carolina Communities Located in Close Proximity to Hog Concentrated Animal Feeding Operations.

BACKGROUND Life expectancy in southeastern North Carolina communities located in an area with multiple concentrated animal feeding operations (CAFOs) after adjusting for socioeconomic factors remains low. We hypothesized that poor health outcomes in this region may be due to converging demographic, socioeconomic, behavioral, and access-to-care factors and are influenced by the presence of hog CAFOs.METHODS We studied mortality, hospital admissions, and emergency department (ED) usage for health conditions potentially associated with hog CAFOs-anemia, kidney disease, infectious diseases, and low birth weight (LBW)-in North Carolina communities located in zip codes with hog CAFOs (Study group 1), in zip codes with > 215hogs/km2 (Study group 2), and without hog CAFOs (Control group). We compared cause-specific age-adjusted rates, the odds ratios (ORs) of events in multivariable analyses (adjusted for 6 co-factors), and the changes of ORs relative to the distance to hog CAFOs.RESULTS Residents from Study groups 1 and 2 had higher rates of all-cause mortality, infant mortality, mortality of patients with multimorbidity, mortality from anemia, kidney disease, tuberculosis, and septicemia, and higher rates of ED visits and hospital admissions for LBW infants than the residents in the Control group. In zip codes with > 215hogs/km2, mortality ORs were 1.50 for anemia (P < 0.0001), 1.31 for kidney disease (P < 0.0001), 2.30 for septicemia (P < 0.0001), and 2.22 for tuberculosis (P = 0.0061).LIMITATIONS This study included a lack of individual measurements on environmental contaminants, biomarkers of exposures and co-factors, and differences in residential and occupational locations.CONCLUSION North Carolina communities located near hog CAFOs had higher all-cause and infant mortality, mortality due to anemia, kidney disease, tuberculosis, septicemia, and higher hospital admissions/ED visits of LBW infants. Although not establishing causality with exposures from hog CAFOs, our findings support the need for future studies to determine factors that influence these outcomes, as well as the need to improve screening and diagnostic strategies for these diseases in North Carolina communities adjacent to hog CAFOs.

The Impact of Coal-Powered Electrical Plants and Coal Ash Impoundments on the Health of Residential Communities.

BACKGROUND In North Carolina, coal-burning power plants remain the major source of electrical production. Coal burning generates coal ash that is stored in landfills and slurry ponds that are often located near residential communities, signifying high potential for environmental contamination and increasing health risks. We reviewed the literature on potential health effects of coal-burning plants to summarize current knowledge on health risks.METHODS We searched English-language publications issued between January 1, 1987, and December 31, 2017, on PubMed and Google Scholar.RESULTS The algorithm of identification, screening, eligibility, and inclusion/exclusion we used provided 113 peer-reviewed publications selected for the review. Over the past 30 years, scientists reported that the people living in close proximity to coal-fired plants had higher rates of all-cause and premature mortality, increased risk of respiratory disease and lung cancer, cardiovascular disease, poorer child health, and higher infant mortality. The elevated health risk was associated with exposure to air pollutants from the power plant emissions and to a spectrum of heavy metals and radioactive isotopes in coal ash.CONCLUSION In North Carolina, further studies are required to profile the severity of the cumulative impacts of multiple air, water, and soil contaminants related to coal-burning power plants and coal ash impoundments on human health and the environment. Prioritized study directions on evaluation of health impacts of coal-burning power plants in North Carolina are suggested.

The Health Impacts of Environmental Policy: The North Carolina Clean Smokestacks Act.

The North Carolina Clean Smokestacks Act and related policies led to substantial decreases of emitted air pollutants from coal-fired power plants. Improved air quality was associated with statewide improvements in respiratory, cardiovascular, and cerebrovascular health in North Carolina. The effectiveness of environmental policies can be monitored for impact on both environmental and health outcomes.

Time trends in the prevalence of cancer and non-cancer diseases among older U.S. adults: Medicare-based analysis.

Longer lifespan is accompanied by a larger number of chronic diseases among older adults. Because of a growing proportion of older adults in the U.S., this brings the problem of age-related morbidity to the forefront as a major contributor to rising medical expenditures. We evaluated 15-year time trends (from 1998 to 2013) in the prevalence of 48 acute and chronic non-cancer diseases and cancers in older U.S. adults aged 65+ and estimated the annual percentage changes of these prevalence trends using SEER-Medicare and HRS-Medicare data. We found that age-adjusted prevalence of cancers of kidney, pancreas, and melanoma, as well as diabetes, renal disease, limb fracture, depression, anemia, weight deficiency, dementia/Alzheimer's disease, drug/medications abuse and several other diseases/conditions increased over time. Conversely, prevalence of myocardial infarction, heart failure, cardiomyopathy, pneumonia/influenza, peptic ulcer, and gastrointestinal bleeding, among others, decreased over time. There are also diseases whose prevalence did not change substantially over time, e.g., a group of fast progressing cancers and rheumatoid arthritis. Analysis of trends of multiple diseases performed simultaneously within one study design with focus on the same time interval and the same population for all diseases allowed us to provide insight into the epidemiology of these conditions and identify the most alarming and/or unexpected trends and trade-offs. The obtained results can be used for health expenditures planning for growing sector of older adults in the U.S.

Time Trends in the Prevalence of Neurocognitive Disorders and Cognitive Impairment in the United States: The Effects of Disease Severity and Improved Ascertainment.

BACKGROUND: Trends in the prevalence of cognitive impairment (CI) based on cognitive assessment instruments are often inconsistent with those of neurocognitive disorders (ND) based on Medicare claims records. OBJECTIVE: We hypothesized that improved ascertainment and resulting decrease in disease severity at the time of diagnosis are responsible for this phenomenon. METHODS: Using Medicare data linked to the Health and Retirement Study (1992-2012), we performed a joint analysis of trends in CI and ND to test our hypothesis. RESULTS: We identified two major contributors to the divergent directions in CI and ND trends: reductions in disease severity explained more than 60% of the differences between CI and ND prevalence over the study period; the remaining 40% was explained by a decrease in the fraction of undiagnosed individuals. DISCUSSION: Improvements in the diagnoses of ND diseases were a major contributor to reported trends in ND and CI. Recent forecasts of CI and ND trends in the U.S. may be overly pessimistic.

Identifying the causes of the changes in the prevalence patterns of diabetes in older U.S. adults: A new trend partitioning approach.

AIMS: To identify how efforts to control the diabetes epidemic and the resulting changes in diabetes mellitus, type II (T2D) incidence and survival have affected the time-trend of T2D prevalence. METHODS: A newly developed method of trend decomposition was applied to a 5% sample of Medicare administrative claims filed between 1991 and 2012. RESULTS: Age-adjusted prevalence of T2D for adults age 65+ increased at an average annual percentage change of 2.31% between 1992 and 2012. Primary contributors to this trend were (in order of magnitude): improved survival at all ages, increased prevalence of T2D prior to age of Medicare eligibility, decreased incidence of T2D after age of Medicare eligibility. CONCLUSIONS: Health services supported by the Medicare system, coupled with improvements in medical technology and T2D awareness efforts provide effective care for individuals age 65 and older. However, policy maker attention should be shifted to the prevention of T2D in younger age groups to control the increase in prevalence observed prior to Medicare eligibility.

Mortality and Macrovascular Risk in Elderly With Hypertension and Diabetes: Effect of Intensive Drug Therapy.

BACKGROUND: This study identifies the effect of intensive drug therapy (IDT) in individuals age 65+ with diabetes (type 2 diabetes mellitus (T2D)) and hypertension on all-cause death, congestive heart failure (CHF), hospitalization for myocardial infarction (MI), and stroke or transient ischemic attack (TIA). METHODS: Individuals from the Medicare 5% dataset with hypertension and T2D undergoing IDT for these conditions were propensity score matched to a nonintensive drug-therapy group. Hazard ratios (HRs) were obtained using the Cox proportional hazard model. RESULTS: IDT was associated with increased risk of CHF (HR 2.32; 95% confidence interval (CI) 2.32-2.38), MI (HR 4.27; 95% CI 4.05-4.52), and stroke or TIA (HR 1.80; 95% CI 1.70-1.89) but decreased risk of death (HR 0.95; 95% CI 0.93-0.97). Risk for CHF (HR 0.73; 95% CI 0.71-0.73), MI (HR 0.64; 95% CI 0.62-0.67), stroke or TIA (HR 0.82; 95% CI 0.78-0.86), and death (HR 0.29; 95% CI 0.28-0.29) was decreased by adherence to diabetes management guidelines. CONCLUSIONS: Use of IDT in a high-risk population delays death but not severe macrovascular outcomes. Protective effects of IDT in high-risk patients likely outweigh polypharmacy-related health concerns.