Effects of residential socioeconomic polarization on high blood pressure among nursing home residents

OBJECTIVE

Neighborhood concentration of racial, income, education, and housing deprivation is known to be associated with higher rates of hypertension. The objective of this study is to examine the association between tract-level spatial social polarization and hypertension in a cohort with relatively equal access to health care, a Veterans Affairs nursing home.

METHODS

41,973 long-term care residents aged ≥65 years were matched with tract-level Indices of Concentration at the Extremes across four socioeconomic domains. We modeled high blood pressure against these indices controlling for individual-level cardiovascular confounders.

RESULTS

We found participants who had resided in the most disadvantaged quintile had a 1.10 (95% 1.01, 1.19) relative risk of high blood pressure compared to those in the other quintiles for the joint measuring race/ethnicity and income domain.

CONCLUSIONS

We achieved our objective by demonstrating that concentrated deprivation is associated with worse cardiovascular outcomes even in a population with equal access to care. Measures that jointly consider economic and racial/ethnic polarization elucidate larger disparities than single domain measures.

Antihypertensive Medication and Fracture Risk in Older Veterans Health Administration Nursing Home Residents

Importance

Limited evidence exists on the association between initiation of antihypertensive medication and risk of fractures in older long-term nursing home residents.

Objective

To assess the association between antihypertensive medication initiation and risk of fracture.

Design, Setting, and Participants

This was a retrospective cohort study using target trial emulation for data derived from 29 648 older long-term care nursing home residents in the Veterans Health Administration (VA) from January 1, 2006, to October 31, 2019. Data were analyzed from December 1, 2021, to November 11, 2023.

Exposure

Episodes of antihypertensive medication initiation were identified, and eligible initiation episodes were matched with comparable controls who did not initiate therapy.

Main Outcome and Measures

The primary outcome was nontraumatic fracture of the humerus, hip, pelvis, radius, or ulna within 30 days of antihypertensive medication initiation. Results were computed among subgroups of residents with dementia, across systolic and diastolic blood pressure thresholds of 140 and 80 mm Hg, respectively, and with use of prior antihypertensive therapies. Analyses were adjusted for more than 50 baseline covariates using 1:4 propensity score matching.

Results

Data from 29 648 individuals were included in this study (mean [SD] age, 78.0 [8.4] years; 28 952 [97.7%] male). In the propensity score-matched cohort of 64 710 residents (mean [SD] age, 77.9 [8.5] years), the incidence rate of fractures per 100 person-years in residents initiating antihypertensive medication was 5.4 compared with 2.2 in the control arm. This finding corresponded to an adjusted hazard ratio (HR) of 2.42 (95% CI, 1.43-4.08) and an adjusted excess risk per 100 person-years of 3.12 (95% CI, 0.95-6.78). Antihypertensive medication initiation was also associated with higher risk of severe falls requiring hospitalizations or emergency department visits (HR, 1.80 [95% CI, 1.53-2.13]) and syncope (HR, 1.69 [95% CI, 1.30-2.19]). The magnitude of fracture risk was numerically higher among subgroups of residents with dementia (HR, 3.28 [95% CI, 1.76-6.10]), systolic blood pressure of 140 mm Hg or higher (HR, 3.12 [95% CI, 1.71-5.69]), diastolic blood pressure of 80 mm Hg or higher (HR, 4.41 [95% CI, 1.67-11.68]), and no recent antihypertensive medication use (HR, 4.77 [95% CI, 1.49-15.32]).

Conclusions and Relevance

Findings indicated that initiation of antihypertensive medication was associated with elevated risks of fractures and falls. These risks were numerically higher among residents with dementia, higher baseline blood pressures values, and no recent antihypertensive medication use. Caution and additional monitoring are advised when initiating antihypertensive medication in this vulnerable population.

Which older adults are at highest risk of prescribing cascades? A national study of the gabapentinoid-loop diuretic cascade

BACKGROUND

Prescribing cascades are important contributors to polypharmacy. Little is known about which older adults are at highest risk of experiencing prescribing cascades. We explored which older veterans are at highest risk of the gabapentinoid (including gabapentin and pregabalin)-loop diuretic (LD) cascade, given the dramatic increase in gabapentinoid prescribing in recent years.

METHODS

Using Veterans Affairs and Medicare claims data (2010-2019), we performed a prescription sequence symmetry analysis (PSSA) to assess loop diuretic initiation before and after gabapentinoid initiation among older veterans (≥66 years). To identify the cascade, we calculated the adjusted sequence ratio (aSR), which assesses the temporality of LD relative to gabapentinoid initiation. To explore high-risk groups, we used multivariable logistic regression with prescribing order modeled as a binary dependent variable. We calculated adjusted odds ratios (aORs), measuring the extent to which factors are associated with one prescribing order versus another.

RESULTS

Of 151,442 veterans who initiated a gabapentinoid, there were 1,981 patients who initiated a LD within 6 months after initiating a gabapentinoid compared to 1,599 patients who initiated a LD within 6 months before initiating a gabapentinoid. In the gabapentinoid-LD group, the mean age was 73 years, 98% were male, 13% were Black, 5% were Hispanic, and 80% were White. Patients in each group were similar across patient and health utilization factors (standardized mean difference <0.10 for all comparisons). The aSR was 1.23 (95% CI: 1.13, 1.34), strongly suggesting the cascade's presence. People age ≥85 years were less likely to have the cascade (compared to 66-74 years; aOR 0.74, 95% CI: 0.56-0.96), and people taking ≥10 medications were more likely to have the cascade (compared to 0-4 drugs; aOR 1.39, 95% CI: 1.07-1.82).

CONCLUSIONS

Among older adults, those who are younger and taking many medications may be at higher risk of the gabapentinoid-LD cascade, contributing to worsening polypharmacy and potential drug-related harms. We did not identify strong predictors of this cascade, suggesting that prescribing cascade prevention efforts should be widespread rather than focused on specific subgroups.

Synthetic Health Data Can Augment Community Research Efforts to Better Inform the Public During Emerging Pandemics

The COVID-19 pandemic had disproportionate effects on the Veteran population due to the increased prevalence of medical and environmental risk factors. Synthetic electronic health record (EHR) data can help meet the acute need for Veteran population-specific predictive modeling efforts by avoiding the strict barriers to access, currently present within Veteran Health Administration (VHA) datasets. The U.S. Food and Drug Administration (FDA) and the VHA launched the precisionFDA COVID-19 Risk Factor Modeling Challenge to develop COVID-19 diagnostic and prognostic models; identify Veteran population-specific risk factors; and test the usefulness of synthetic data as a substitute for real data. The use of synthetic data boosted challenge participation by providing a dataset that was accessible to all competitors. Models trained on synthetic data showed similar but systematically inflated model performance metrics to those trained on real data. The important risk factors identified in the synthetic data largely overlapped with those identified from the real data, and both sets of risk factors were validated in the literature. Tradeoffs exist between synthetic data generation approaches based on whether a real EHR dataset is required as input. Synthetic data generated directly from real EHR input will more closely align with the characteristics of the relevant cohort. This work shows that synthetic EHR data will have practical value to the Veterans' health research community for the foreseeable future.

Tutorial: Assessing the impact of nonignorable missingness on regression analysis using Index of Local Sensitivity to Nonignorability

Data sets with missing observations are common in psychology research. One typically analyzes such data by applying statistical methods that rely on the assumption that the missing observations are missing at random (MAR). This assumption greatly simplifies analysis but is unverifiable from the data at hand, and assuming it incorrectly may lead to bias. Thus we often wish to conduct sensitivity analyses to judge whether conclusions are robust to departures from MAR-that is, whether key findings would hold up even if MAR does not in fact hold. This article describes a class of sensitivity analyses derived from a measure of robustness called the Index of Local Sensitivity to Nonignorability (ISNI). ISNI is straightforward to compute and avoids the estimation of complicated non-MAR missing-data models. The accompanying R package isni implements the method for a range of commonly used regression models; the syntax is simple and similar to that for the regular analysis that assumes MAR. We illustrate the application of the method and software to address the credibility of MAR analyses in a series of analyses of real-world data sets from psychology research. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Frequency of Screening for Colorectal Cancer by Predicted Life Expectancy Among Adults 76-85 Years

This study assesses whether colorectal cancer screening varied by predicted life expectancy in a national sample of Veterans Affairs patients aged 76 to 85 years.

Medication misuse and overuse in community-dwelling persons with dementia

BACKGROUND

Persons with dementia (PWD) have high rates of polypharmacy. While previous studies have examined specific types of problematic medication use in PWD, we sought to characterize a broad spectrum of medication misuse and overuse among community-dwelling PWD.

METHODS

We included community-dwelling adults aged ≥66 in the Health and Retirement Study from 2008 to 2018 linked to Medicare and classified as having dementia using a validated algorithm. Medication usage was ascertained over the 1-year prior to an HRS interview date. Potentially problematic medications were identified by: (1) medication overuse including over-aggressive treatment of diabetes/hypertension (e.g., insulin/sulfonylurea with hemoglobin A1c < 7.5%) and medications inappropriate near end of life based on STOPPFrail and (2) medication misuse including medications that negatively affect cognition and medications from 2019 Beers and STOPP Version 2 criteria. To contextualize, we compared medication use to people without dementia through a propensity-matched cohort by age, sex, comorbidities, and interview year. We applied survey weights to make our results nationally representative.

RESULTS

Among 1441 PWD, median age was 84 (interquartile range = 78-89), 67% female, and 14% Black. Overall, 73% of PWD were prescribed ≥1 potentially problematic medication with a mean of 2.09 per individual in the prior year. This was notable across several domains, including 41% prescribed ≥1 medication that negatively affects cognition. Frequently problematic medications included proton pump inhibitors (PPIs), non-steroidal anti-inflammatory drugs (NSAIDs), opioids, antihypertensives, and antidiabetic agents. Problematic medication use was higher among PWD compared to those without dementia with 73% versus 67% prescribed ≥1 problematic medication (p = 0.002) and mean of 2.09 versus 1.62 (p < 0.001), respectively.

CONCLUSION

Community-dwelling PWD frequently receive problematic medications across multiple domains and at higher frequencies compared to those without dementia. Deprescribing efforts for PWD should focus not only on potentially harmful central nervous system-active medications but also on other classes such as PPIs and NSAIDs.

Clinical Outcomes of Intensive Inpatient Blood Pressure Management in Hospitalized Older Adults

Importance

Asymptomatic blood pressure (BP) elevations are common in hospitalized older adults, and widespread heterogeneity in the clinical management of elevated inpatient BPs exists.

Objective

To examine the association of intensive treatment of elevated inpatient BPs with in-hospital clinical outcomes of older adults hospitalized for noncardiac conditions.

Design, Setting, and Participants

This retrospective cohort study examined Veterans Health Administration data between October 1, 2015, and December 31, 2017, for patients aged 65 years or older hospitalized for noncardiovascular diagnoses and who experienced elevated BPs in the first 48 hours of hospitalization.

Interventions

Intensive BP treatment following the first 48 hours of hospitalization, defined as receipt of intravenous antihypertensives or oral classes not used prior to admission.

Main Outcome and Measures

The primary outcome was a composite of inpatient mortality, intensive care unit transfer, stroke, acute kidney injury, B-type natriuretic peptide elevation, and troponin elevation. Data were analyzed between October 1, 2021, and January 10, 2023, with propensity score overlap weighting used to adjust for confounding between those who did and did not receive early intensive treatment.

Results

Among 66 140 included patients (mean [SD] age, 74.4 [8.1] years; 97.5% male and 2.6% female; 17.4% Black, 1.7% Hispanic, and 75.9% White), 14 084 (21.3%) received intensive BP treatment in the first 48 hours of hospitalization. Patients who received early intensive treatment vs those who did not continued to receive a greater number of additional antihypertensives during the remainder of their hospitalization (mean additional doses, 6.1 [95% CI, 5.8-6.4] vs 1.6 [95% CI, 1.5-1.8], respectively). Intensive treatment was associated with a greater risk of the primary composite outcome (1220 [8.7%] vs 3570 [6.9%]; weighted odds ratio [OR], 1.28; 95% CI, 1.18-1.39), with the highest risk among patients receiving intravenous antihypertensives (weighted OR, 1.90; 95% CI, 1.65-2.19). Intensively treated patients were more likely to experience each component of the composite outcome except for stroke and mortality. Findings were consistent across subgroups stratified by age, frailty, preadmission BP, early hospitalization BP, and cardiovascular disease history.

Conclusions and Relevance

The study's findings indicate that among hospitalized older adults with elevated BPs, intensive pharmacologic antihypertensive treatment was associated with a greater risk of adverse events. These findings do not support the treatment of elevated inpatient BPs without evidence of end organ damage, and they highlight the need for randomized clinical trials of inpatient BP treatment targets.

Systolic blood pressure, antihypertensive treatment, and cardiovascular and mortality risk in VA nursing home residents

BACKGROUND

Optimal systolic BP (SBP) control in nursing home residents is uncertain, largely because this population has been excluded from clinical trials. We examined the association of SBP levels with the risk of cardiovascular (CV) events and mortality in Veterans Affairs (VA) nursing home residents on different numbers of antihypertensive medications.

METHODS

Our study included 36,634 residents aged ≥65 years with a VA nursing home stay of ≥90 days from October 2006-June 2019. SBP was averaged over the first week after admission and divided into categories. Cause-specific hazard ratios (HRs) of SBP categories with CV events (primary outcome) and all-cause mortality (secondary outcome) were examined using Cox regression and multistate modeling stratified by the number of antihypertensive medications used at admission (0, 1 or 2, and ≥3 medications).

RESULTS

More than 76% of residents were on antihypertensive therapy and 20% received ≥3 medications. In residents on antihypertensive therapy, a low SBP < 110 mmHg (compared with SBP 130 ~ 149 mmHg) was associated with a greater CV risk (adjusted HR [95% confidence interval]: 1.47 [1.28-1.68] in 1 or 2 medications group, and 1.41 [1.19-1.67] in ≥3 medications group). In residents on no antihypertensives, both low SBP < 110 mmHg and high SBP ≥ 150 mmHg were associated with higher mortality; while in residents receiving any antihypertensives, a low SBP was associated with higher mortality and the highest point estimates were for SBP < 110 mmHg (1.36 [1.28-1.45] in 1 or 2 medications group, and 1.47 [1.31-1.64] in ≥3 medications group).

CONCLUSIONS

The associations of SBP with CV and mortality risk varied by the intensity of antihypertensive treatment among VA nursing home residents. A low SBP among those receiving antihypertensives was associated with increased CV and mortality risk, and untreated high SBP was associated with higher mortality. More research is needed on the benefits and harms of SBP lowering in long-term care populations.

Can markers of disease severity improve the predictive power of claims-based multimorbidity indices?

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.

Development and validation of novel multimorbidity indices for older adults

BACKGROUND

Measuring multimorbidity in claims data is used for risk adjustment and identifying populations at high risk for adverse events. Multimorbidity indices such as Charlson and Elixhauser scores have important limitations. We sought to create a better method of measuring multimorbidity using claims data by incorporating geriatric conditions, markers of disease severity, and disease-disease interactions, and by tailoring measures to different outcomes.

METHODS

Health conditions were assessed using Medicare inpatient and outpatient claims from subjects age 67 and older in the Health and Retirement Study. Separate indices were developed for ADL decline, IADL decline, hospitalization, and death, each over 2 years of follow-up. We validated these indices using data from Medicare claims linked to the National Health and Aging Trends Study.

RESULTS

The development cohort included 5012 subjects with median age 76 years; 58% were female. Claims-based markers of disease severity and disease-disease interactions yielded minimal gains in predictive power and were not included in the final indices. In the validation cohort, after adjusting for age and sex, c-statistics for the new multimorbidity indices were 0.72 for ADL decline, 0.69 for IADL decline, 0.72 for hospitalization, and 0.77 for death. These c-statistics were 0.02-0.03 higher than c-statistics from Charlson and Elixhauser indices for predicting ADL decline, IADL decline, and hospitalization, and <0.01 higher for death (p < 0.05 for each outcome except death), and were similar to those from the CMS-HCC model. On decision curve analysis, the new indices provided minimal benefit compared with legacy approaches. C-statistics for both new and legacy indices varied substantially across derivation and validation cohorts.

CONCLUSIONS

A new series of claims-based multimorbidity measures were modestly better at predicting hospitalization and functional decline than several legacy indices, and no better at predicting death. There may be limited opportunity in claims data to measure multimorbidity better than older methods.

UNNECESSARY AND HARMFUL MEDICATION USE IN COMMUNITY DWELLING PERSONS WITH DEMENTIA

Persons with dementia (PWD) often have multiple comorbidities which results in extensive medication use despite potentially limited benefit and increased risk of adverse events. Compared to the nursing home, little is known about medication overuse and misuse among the ~70% of PWD in the community. Therefore, we examined medication use from Medicare Part D prescriptions among 1,289 community-dwelling PWD aged ≥66 from the Health and Retirement Study. We classified medication overuse as over-aggressive treatment of chronic conditions (e.g., insulin/sulfonylurea use with hemoglobin A1c<7.5%) and medications inappropriate near the end of life. We classified medication misuse as medications that negatively affect cognition (strongly anticholinergics/sedative-hypnotics) and problematic medications (using Beers and STOPP criteria). We describe the prevalence and patterns of different types of medication overuse/misuse. Frequently problematic medications included antipsychotics (9%), benzodiazepines (12%), and gabapentinoids (13%). Our findings highlight the burden of unnecessary/harmful medications among PWD and inform future deprescribing interventions.

Fingerstick glucose monitoring by cognitive impairment status in Veterans Affairs nursing home residents with diabetes

BACKGROUND

Guidelines recommend nursing home (NH) residents with cognitive impairment receive less intensive glycemic treatment and less frequent fingerstick monitoring. Our objective was to determine whether current practice aligns with guideline recommendations by examining fingerstick frequency in Veterans Affairs (VA) NH residents with diabetes across cognitive impairment levels.

METHODS

We identified VA NH residents with diabetes aged ≥65 residing in VA NHs for >30 days between 2016 and 2019. Residents were grouped by cognitive impairment status based on the Cognitive Function Scale: cognitively intact, mild impairment, moderate impairment, and severe impairment. We also categorized residents into mutually exclusive glucose-lowering medication (GLM) categories: (1) no GLMs, (2) metformin only, (3) sulfonylureas/other GLMs (+/- metformin but no insulin), (4) long-acting insulin (+/- oral/other GLMs but no short-acting insulin), and (5) any short-acting insulin. Our outcome was mean daily fingersticks on day 31 of NH admission.

RESULTS

Among 13,637 NH residents, mean age was 75 years and mean hemoglobin A1c was 7.0%. The percentage of NH residents on short-acting insulin varied by cognitive status from 22.7% in residents with severe cognitive impairment to 33.9% in residents who were cognitively intact. Mean daily fingersticks overall on day 31 was 1.50 (standard deviation = 1.73). There was a greater range in mean fingersticks across GLM categories compared to cognitive status. Fingersticks ranged widely across GLM categories from 0.39 per day (no GLMs) to 3.08 (short-acting insulin), while fingersticks ranged slightly across levels of cognitive impairment from 1.11 (severe cognitive impairment) to 1.59 (cognitively intact).

CONCLUSION

NH residents receive frequent fingersticks regardless of level of cognitive impairment, suggesting that cognitive status is a minor consideration in monitoring decisions. Future studies should determine whether decreasing fingersticks in NH residents with moderate/severe cognitive impairment can reduce burdens without compromising safety.

[The related factors of postoperative recurrence in trigeminalneuralgia patients undergoing fully neuroendoscopic microvascular decompression]

Objective: To evaluate the related factors of postoperative recurrence intrigeminal neuralgia (TN) patients treated with fully neuroendoscopic microvascular decompression (MVD). Methods: The clinical baseline data and preoperative MRI imaging data of 112 patients with TN treated by neuroendoscopic MVD from December 2008 to December 2020 in the Department of Neurosurgery, Beijing Shijitan Hospital Affiliated to Capital Medical University were retrospectively analyzed, including: area ratio of cerebellopontine area (CPA)(healthy side/affected side), trigeminal nerve(TGN)length ratio(healthy side/affected side), TGN angle ratio(healthy side/affected side), and criminal vessel type. Multivariate Cox proportional hazards model was used to analyze the factors affecting postoperative recurrence. Results: Among the 112 patients in this group, there were 49 males and 63 females. The age ranged from 20 to 82 (59±9) years, and the course of disease was 0.05 to 30.00 (5.60±5.15) years. Pain was located on the left side in 43 cases (38.39%) and on the right side in 69 cases (61.61%), respectively. All patients were followed up for more than 1 year, with an average follow-up time of 21.5 months, and 11 cases recurred. Multivariate Cox regression analysis revealed that disease duration≥3 years(HR=9.34, 95%CI:1.12-39.07), CPA area ratio(healthy side/affected side)>1 (HR=27.47, 95%CI:1.69-44.20), criminal vessel type with vein(HR=35.39, 95%CI:1.26-18.60) and criminal vessel type with arteriovenous (HR=46.07, 95%CI: 2.74-27.75) were the main factors influencing recurrence of MVD surgery (all P<0.05). Conclusion: The disease duration≥3 years, CPA area ratio(healthy side/affected side)>1, and criminal vessel type with vein/arteriovenous are the relevant factors that affect the recurrence rate after the fully neuroendoscopic MVD treatment for trigeminal neuralgia.

Trends in blood pressure diagnosis, treatment, and control among VA nursing home residents, 2007-2018

BACKGROUND

Inadequate treatment of high blood pressure (BP) can lead to preventable adverse events in nursing home residents, while excessive treatment can lead to associated harms.

METHODS

Data were extracted from the VA electronic health record and Bar Code Medication Administration system on 40,079 long-term care residents aged ≥65 years from October 2006 through September 2018 (FY2007-2018). Hypertension prevalence at admission was identified by ICD code(s) in the year prior, and antihypertensive medication use was defined as administration ≥50% of days. BP measures were averaged over 2-year epochs.

RESULTS

The age-standardized prevalence of hypertension diagnosis at admission increased from 75.2% in FY2007-2008 to 85.1% in FY2017-2018 (p-value for trend <0.001). Rates of BP treatment and control among residents with hypertension at admission declined slightly over time (p-values for trend <0.001) but remained high (80.3% treated in FY2017-2018, 80.1% with average BP <140/90 mmHg). The age-adjusted prevalence of chronic low BP (average <90/60 mmHg) also declined from 11.1% in FY2007-2008 to 4.7% in FY2017-2018 (p-value for trend <0.001). Persons identified as Black race or Hispanic ethnicity and those with a history of diabetes, stroke, and renal disease were less likely to have an average BP <140/90 mmHg.

CONCLUSIONS

Hypertension is well controlled in VA nursing homes, and recent trends of less intensive BP control were accompanied by a lower prevalence of chronic low BP. Nonetheless, some high-risk populations have average BP levels >140/90 mmHg. Future research is needed to better understand the benefits and harms of BP control in nursing home residents.

Glycemic treatment deintensification practices in nursing home residents with type 2 diabetes

BACKGROUND

Older nursing home (NH) residents with glycemic overtreatment are at significant risk of hypoglycemia and other harms and may benefit from deintensification. However, little is known about deintensification practices in this setting.

METHODS

We conducted a cohort study from January 1, 2013 to December 31, 2019 among Veterans Affairs (VA) NH residents. Participants were VA NH residents age ≥65 with type 2 diabetes with a NH length of stay (LOS) ≥ 30 days and an HbA1c result during their NH stay. We defined overtreatment as HbA1c <6.5 with any insulin use, and potential overtreatment as HbA1c <7.5 with any insulin use or HbA1c <6.5 on any glucose-lowering medication (GLM) other than metformin alone. Our primary outcome was continued glycemic overtreatment without deintensification 14 days after HbA1c.

RESULTS

Of the 7422 included residents, 17% of residents met criteria for overtreatment and an additional 23% met criteria for potential overtreatment. Among residents overtreated and potentially overtreated at baseline, 27% and 19%, respectively had medication regimens deintensified (73% and 81%, respectively, continued to be overtreated). Long-acting insulin use and hyperglycemia ≥300 mg/dL before index HbA1c were associated with increased odds of continued overtreatment (odds ratio [OR] 1.37, 95% confidence interval [CI] 1.14-1.65 and OR 1.35, 95% CI 1.10-1.66, respectively). Severe functional impairment (MDS-ADL score ≥ 19) was associated with decreased odds of continued overtreatment (OR 0.72, 95% CI 0.56-0.95). Hypoglycemia was not associated with decreased odds of overtreatment.

CONCLUSIONS

Overtreatment of diabetes in NH residents is common and a minority of residents have their medication regimens appropriately deintensified. Deprescribing initiatives targeting residents at high risk of harms and with low likelihood of benefit such as those with history of hypoglycemia, or high levels of cognitive or functional impairment are most likely to identify NH residents most likely to benefit from deintensification.

Sliding scale insulin use in a national cohort study of nursing home residents with type 2 diabetes

BACKGROUND

Guidelines discourage sliding scale insulin (SSI) use after the first week of a nursing home (NH) admission. We sought to determine the prevalence of SSI and identify factors associated with stopping SSI or transitioning to another short-acting insulin regimen.

METHODS

In an observational study from October 1, 2013, to June 30, 2017 of non-hospice Veterans Affairs NH residents with type 2 diabetes and an NH admission over 1 week, we compared the weekly prevalence of SSI versus two other short-acting insulin regimens - fixed dose insulin (FDI) or correction dose insulin (CDI, defined as variable SSI given alongside fixed doses of insulin) - from week 2 to week 12 of admission. Among those on SSI in week 2, we examined factors associated with stopping SSI or transitioning to other regimens by week 5. Factors included demographics (e.g., age, sex, race/ethnicity), frailty-related factors (e.g., comorbidities, cognitive impairment, functional impairment), and diabetes-related factors (e.g., HbA1c, long-acting insulin use, hyperglycemia, and hypoglycemia).

RESULTS

In week 2, 21% of our cohort was on SSI, 8% was on FDI, and 7% was on CDI. SSI was the most common regimen in frail subgroups (e.g., 18% of our cohort with moderate-severe cognitive impairment was on SSI vs 5% on FDI and 4% on CDI). SSI prevalence decreased steadily from 21% to 16% at week 12 (p for linear trend <0.001), mostly through stopping SSI. Diabetes-related factors (e.g., hyperglycemia) were more strongly associated with continuing SSI or transitioning to a non-SSI short-acting insulin regimen than frailty-related factors.

CONCLUSIONS

SSI is the most common method of administering short-acting insulin in NH residents. More research needs to be done to explore why sliding scale use persists weeks after NH admission and explore how we can replace this practice with safer, more effective, and less burdensome regimens.

Comparing Machine Learning to Regression Methods for Mortality Prediction Using Veterans Affairs Electronic Health Record Clinical Data

BACKGROUND

It is unclear whether machine learning methods yield more accurate electronic health record (EHR) prediction models compared with traditional regression methods.

OBJECTIVE

The objective of this study was to compare machine learning and traditional regression models for 10-year mortality prediction using EHR data.

DESIGN

This was a cohort study.

SETTING

Veterans Affairs (VA) EHR data.

PARTICIPANTS

Veterans age above 50 with a primary care visit in 2005, divided into separate training and testing cohorts (n= 124,360 each).

MEASUREMENTS AND ANALYTIC METHODS

The primary outcome was 10-year all-cause mortality. We considered 924 potential predictors across a wide range of EHR data elements including demographics (3), vital signs (9), medication classes (399), disease diagnoses (293), laboratory results (71), and health care utilization (149). We compared discrimination (c-statistics), calibration metrics, and diagnostic test characteristics (sensitivity, specificity, and positive and negative predictive values) of machine learning and regression models.

RESULTS

Our cohort mean age (SD) was 68.2 (10.5), 93.9% were male; 39.4% died within 10 years. Models yielded testing cohort c-statistics between 0.827 and 0.837. Utilizing all 924 predictors, the Gradient Boosting model yielded the highest c-statistic [0.837, 95% confidence interval (CI): 0.835-0.839]. The full (unselected) logistic regression model had the highest c-statistic of regression models (0.833, 95% CI: 0.830-0.835) but showed evidence of overfitting. The discrimination of the stepwise selection logistic model (101 predictors) was similar (0.832, 95% CI: 0.830-0.834) with minimal overfitting. All models were well-calibrated and had similar diagnostic test characteristics.

LIMITATION

Our results should be confirmed in non-VA EHRs.

CONCLUSION

The differences in c-statistic between the best machine learning model (924-predictor Gradient Boosting) and 101-predictor stepwise logistic models for 10-year mortality prediction were modest, suggesting stepwise regression methods continue to be a reasonable method for VA EHR mortality prediction model development.

Do functional status and Medicare claims data improve the predictive accuracy of an electronic health record mortality index? Findings from a national Veterans Affairs cohort

Background

Electronic health record (EHR) prediction models may be easier to use in busy clinical settings since EHR data can be auto-populated into models. This study assessed whether adding functional status and/or Medicare claims data (which are often not available in EHRs) improves the accuracy of a previously developed Veterans Affairs (VA) EHR-based mortality index.

Methods

This was a retrospective cohort study of veterans aged 75 years and older enrolled in VA primary care clinics followed from January 2014 to April 2020 (n = 62,014). We randomly split participants into development (n = 49,612) and validation (n = 12,402) cohorts. The primary outcome was all-cause mortality. We performed logistic regression with backward stepwise selection to develop a 100-predictor base model using 854 EHR candidate variables, including demographics, laboratory values, medications, healthcare utilization, diagnosis codes, and vitals. We incorporated functional measures in a base + function model by adding activities of daily living (range 0-5) and instrumental activities of daily living (range 0-7) scores. Medicare data, including healthcare utilization (e.g., emergency department visits, hospitalizations) and diagnosis codes, were incorporated in a base + Medicare model. A base + function + Medicare model included all data elements. We assessed model performance with the c-statistic, reclassification metrics, fraction of new information provided, and calibration plots.

Results

In the overall cohort, mean age was 82.6 years and 98.6% were male. At the end of follow-up, 30,263 participants (48.8%) had died. The base model c-statistic was 0.809 (95% CI 0.805-0.812) in the development cohort and 0.804 (95% CI 0.796-0.812) in the validation cohort. Validation cohort c-statistics for the base + function, base + Medicare, and base + function + Medicare models were 0.809 (95% CI 0.801-0.816), 0.811 (95% CI 0.803-0.818), and 0.814 (95% CI 0.807-0.822), respectively. Adding functional status and Medicare data resulted in similarly small improvements among other model performance measures. All models showed excellent calibration.

Conclusions

Incorporation of functional status and Medicare data into a VA EHR-based mortality index led to small but likely clinically insignificant improvements in model performance.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03126-z.

Attitudes toward deprescribing among older adults with dementia in the United States

BACKGROUND

People with dementia (PWD) take medications that may be unnecessary or harmful. This problem can be addressed through deprescribing, but it is unclear if PWD would be willing to engage in deprescribing with their providers. Our goal was to investigate attitudes toward deprescribing among PWD.

METHODS

This was a cross-sectional study of 422 PWD aged ≥65 years who completed the medications attitudes module of the National Health and Aging Trends Study (NHATS) in 2016. Proxies provided responses when a participant was unable to respond due to health or cognitive problems. Attitudinal outcomes comprised responses to two statements from the patients' attitudes toward deprescribing questionnaire and its revised version (representing belief about the necessity of one's medications and willingness to deprescribe); another elicited the maximum number of pills that a respondent would be comfortable taking.

RESULTS

The weighted sample represented over 1.8 million PWD; 39% were 75 to 84 years old and 38% were 85 years or older, 60% were female, and 55% reported six or more regular medications. Proxies provided responses for 26% of PWD. Overall, 22% believed that they may be taking one or more medicines that they no longer needed, 87% were willing to stop one or more of their medications, and 50% were uncomfortable taking five or more medications. Attitudinal outcomes were similar across sociodemographic and clinical factors. PWD taking ≥6 medications were more likely to endorse a belief that at least one medication was no longer necessary compared to those taking <6 (adjusted probability 29% [95% confidence interval (CI), 22%-38%] vs. 13% [95% CI, 8%-20%]; p = 0.004); the same applied for willingness to deprescribe (92% [95% CI, 87%-95%] vs. 83% [95% CI, 76%-89%]; p = 0.04).

CONCLUSIONS

A majority of PWD are willing to deprescribe, representing an opportunity to improve quality of life for this vulnerable population.

Predicting Life Expectancy to Target Cancer Screening Using Electronic Health Record Clinical Data

BACKGROUND

Guidelines recommend breast and colorectal cancer screening for older adults with a life expectancy >10 years. Most mortality indexes require clinician data entry, presenting a barrier for routine use in care. Electronic health records (EHR) are a rich clinical data source that could be used to create individualized life expectancy predictions to identify patients for cancer screening without data entry.

OBJECTIVE

To develop and internally validate a life expectancy calculator from structured EHR data.

DESIGN

Retrospective cohort study using national Veteran's Affairs (VA) EHR databases.

PATIENTS

Veterans aged 50+ with a primary care visit during 2005.

MAIN MEASURES

We assessed demographics, diseases, medications, laboratory results, healthcare utilization, and vital signs 1 year prior to the index visit. Mortality follow-up was complete through 2017. Using the development cohort (80% sample), we used LASSO Cox regression to select ~100 predictors from 913 EHR data elements. In the validation cohort (remaining 20% sample), we calculated the integrated area under the curve (iAUC) and evaluated calibration.

KEY RESULTS

In 3,705,122 patients, the mean age was 68 years and the majority were male (97%) and white (85%); nearly half (49%) died. The life expectancy calculator included 93 predictors; age and gender most strongly contributed to discrimination; diseases also contributed significantly while vital signs were negligible. The iAUC was 0.816 (95% confidence interval, 0.815, 0.817) with good calibration.

CONCLUSIONS

We developed a life expectancy calculator using VA EHR data with excellent discrimination and calibration. Automated life expectancy prediction using EHR data may improve guideline-concordant breast and colorectal cancer screening by identifying patients with a life expectancy >10 years.

Exploring the Dynamics of Week-to-Week Blood Pressure in Nursing Home Residents Before Death

BACKGROUND

Aging is accompanied by an overall dysregulation of many dynamic physiologic processes including those related to blood pressure (BP). While year-to-year BP variability is associated with cardiovascular events and mortality, no studies have examined this trend with more frequent BP assessments. Our study objective is to take the next step to examine week-to-week BP dynamics-pattern, variability, and complexity-before death.

METHODS

Using a retrospective study design, we assessed BP dynamics in the 6 months before death in long-term nursing home residents between 1 October 2006 and 30 September 2017. Variability was characterized using SD and mean squared error after adjusting for diurnal variations. Complexity (i.e., amount of novel information in a trend) was examined using Shannon's entropy (bits). Generalized linear models were used to examine factors associated with overall BP variability.

RESULTS

We identified 17,953 nursing home residents (98.0% male, 82.5% White, mean age 80.2 years, and mean BP 125.7/68.6 mm Hg). Despite a slight trend of decreasing systolic week-to-week BP over time (delta = 7.2 mm Hg), week-to-week complexity did not change in the 6 months before death (delta = 0.02 bits). Average weekly BP variability was stable until the last 3-4 weeks of life, at which point variability increased by 30% for both systolic and diastolic BP. Factors associated with BP variability include average weekly systolic/diastolic BP, days in the nursing home, days in the hospital, and changes to antihypertensive medications.

CONCLUSIONS

Week-to-week BP variability increases substantially in the last month of life, but complexity does not change. Changes in care patterns may drive the increase in BP variability as one approaches death.

Association of Antihypertensives and Cognitive Impairment in Long-Term Care Residents

BACKGROUND

Certain classes of antihypertensive medication may have different associations with cognitive impairment.

OBJECTIVE

To examine the association between prevalent use of antihypertensive medications that stimulate (thiazides, dihydropyridine calcium channel blockers, angiotensin type I receptor blockers) versus inhibit (angiotensin-converting enzyme inhibitors, beta-blockers, non-dihydropyridine calcium channel blockers) type 2 and 4 angiotensin II receptors on cognitive impairment among older adults residing in Veterans Affairs (VA) nursing homes for long-term care.

METHODS

Retrospective cohort study. Long-term care residents aged 65 + years admitted to a VA nursing home from 2012 to 2019 using blood pressure medication and without cognitive impairment at admission. Main exposure was prevalent use of angiotensin II receptor type 2 and 4-'stimulating' (N = 589), 'inhibiting' (N = 3,219), or 'mixed' (N = 1,715) antihypertensive medication regimens at admission. Primary outcome was any cognitive impairment (Cognitive Function Scale).

RESULTS

Over an average of 5.4 months of follow-up, prevalent use of regimens containing exclusively 'stimulating' antihypertensives was associated with a lower risk of any incident cognitive impairment as compared to prevalent use of regimens containing exclusively 'inhibiting' antihypertensives (HR 0.83, 95% CI 0.74-0.93). Results for the comparison between 'mixed' versus 'inhibiting' regimens were in the same direction but not statistically significant (HR 0.96, 95% CI 0.88-1.06).

CONCLUSION

For residents without cognitive impairment at baseline, prevalent users of regimens containing exclusively antihypertensives that stimulate type 2 and 4 angiotensin II receptors had lower rates of cognitive impairment as compared to prevalent users of regimens containing exclusively antihypertensives that inhibit these receptors. Residual confounding cannot be ruled out.

Blood Pressure Variability and Complexity in Nursing Home Residents Before Death

Blood pressure (BP) is a complex dynamic system in the human body and an important determinant of healthy aging. Exploring BP as a dynamic data system may provide important insights into how BP patterns can provide complementary information to the static, one-time BP measurements that are more commonly used for clinical decision making. Thus, we sought to describe BP as a dynamic data system in older adults nearing death. Using a prospective cohort study design, we assessed BP measures 6 months before death in Veterans Health Administrative nursing home residents between 10/1/2006 and 9/30/2017. Variability was characterized using standard deviation and mean square error after adjusting for diurnal variations. Complexity (i.e., amount of novel information vs. redundancy) was examined using Shannon’s entropy (bits). Generalized linear models were used to examine factors associated with overall BP variability. We identified 17,953 patients (98.0% male, 82.5% White, mean age 80.2 years, and mean BP 125.7/68.6 mmHg). In the last 6 months of life, systolic BP decreased slightly (□-7.2mmHg). Variability was stable until the last month of life, at which point variability increased by as much as 30%. In contrast, complexity did not change in the 6 months before death (□0.02 bits). Factors associated with BP variability before death include hospitalizations, hospice care, and medication changes. Systolic BP decreases in the last 6 months before death, and BP variability increases in the last month of life. Further, the increase in BP variability may be driven by increasingly complex care patterns as one approaches death.

Deprescribing Blood Pressure Treatment in VA Long-Term Care Residents

There is growing interest in deprescribing of antihypertensive medications in response to adverse effects, or when a patient’s situation evolves such that the benefits are outweighed by the harms. We conducted a retrospective cohort study to evaluate the incidence and predictors of deprescribing of antihypertensive medication among VA long-term care residents ≥ 65 years admitted between 2006 and 2017. Data were extracted from the VA electronic health record, CMS Minimum Data Set, and Bar Code Medication Administration. Deprescribing was defined as a reduction in the number of antihypertensive medications, sustained for 2 weeks. Potentially triggering events for deprescribing included low blood pressure (<90/60 mmHg), acute renal impairment (creatinine increase of 50%), electrolyte imbalance (potassium below 3.5 mEq/L, sodium decrease by 5 mEq/L), and fall in the past 30 days. Among 22,826 VA nursing home residents on antihypertensive medication, 57% had describing event during their stay (median length of stay = 6 months). Deprescribing events were most common in the first 4 weeks after admission and the last 4 weeks of life. Among potentially triggering events, acute renal impairment was associated with greatest increase in the likelihood of deprescribing over the subsequent 4 weeks: among residents with this event, 32.7% were described compared to 7.3% in those without (risk difference = 25.5%, p<0.001). Falls were associated with the smallest increased risk of deprescribing (risk difference = 2.1%, p<0.001) of the events considered. Deprescribing of antihypertensive medications is common among VA nursing home residents, especially after a potential renal adverse event.

Blood Pressure Control and Cardiovascular and Mortality Risk in VA Nursing Home Residents

Optimal blood pressure (BP) control in nursing home residents is controversial and this population has been excluded from trials. We evaluated the associations of BP level with cardiovascular (CV) events and all-cause mortality across antihypertensive medication categories in Veterans Affairs (VA) nursing home residents. Data for 18,589 residents aged 65 years and older was obtained from the VA Corporate Data Warehouse from October 2006 through September 2017. Baseline systolic BP (SBP) and diastolic BP (DBP) were divided into categories and analyses were stratified by antihypertensive therapy (0, 1, and ≥2 medications). Over a median follow-up of 1.8 years, CV events occurred in 3,519 (19%) residents and 15,897 (86%) residents died. In participants on no BP medications, high SBP (>150 mmHg) was associated with a greater risk of CV events (adjusted [cause-specific] hazard ratio, 1.39; 95% confidence interval, 0.94-2.06) compared with normal SBP (110-130mmHg). By contrast, in participants on ≥2 BP medications, the subgroup with low SBP (<110 mmHg) had a higher CV risk (1.38; 1.20-1.57). For DBP, in participants without BP medications, there were no differences in CV risk across DBP subgroups. Whereas among those on 1 or ≥2 medications, DBP <60 mmHg was associated with a higher CV risk (1.26; 1.03-1.55 and 1.35; 1.18-1.54, respectively) compared with normal DBP (70-80 mmHg). Participants with low SBP (<110 mmHg) and DBP (<70 mmHg) had an increased mortality risk regardless of the number of medications. These findings suggest a potential risk of low BP among nursing home residents on multiple antihypertensive medications.

Intensification of Diabetes Medications at Hospital Discharge and Clinical Outcomes in Older Adults in the Veterans Administration Health System

IMPORTANCE

Transient elevations of blood glucose levels are common in hospitalized older adults with diabetes and may lead clinicians to discharge patients with more intensive diabetes medications than they were using before hospitalization.

OBJECTIVE

To investigate outcomes associated with intensification of outpatient diabetes medications at discharge.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study assessed patients 65 years and older with diabetes not taking insulin who were hospitalized in the Veterans Health Administration Health System between January 1, 2011, and September 28, 2016, for common medical conditions. Data analysis was performed from January 1, 2020, to March 31, 2021.

EXPOSURE

Discharge with intensified diabetes medications, defined as filling a prescription at hospital discharge for a new or higher-dose medication than was being used before hospitalization. Propensity scores were used to construct a matched cohort of patients who did and did not receive diabetes medication intensifications.

MAIN OUTCOMES AND MEASURES

Coprimary outcomes of severe hypoglycemia and severe hyperglycemia were assessed at 30 and 365 days using competing risk regressions. Secondary outcomes included all-cause readmissions, mortality, change in hemoglobin A1c (HbA1c) level, and persistent use of intensified medications at 1 year after discharge.

RESULTS

The propensity-matched cohort included 5296 older adults with diabetes (mean [SD] age, 73.7 [7.7] years; 5212 [98.4%] male; and 867 [16.4%] Black, 47 [0.9%] Hispanic, 4138 [78.1%] White), equally split between those who did and did not receive diabetes medication intensifications at hospital discharge. Within 30 days, patients who received medication intensifications had a higher risk of severe hypoglycemia (hazard ratio [HR], 2.17; 95% CI, 1.10-4.28), no difference in risk of severe hyperglycemia (HR, 1.00; 95% CI, 0.33-3.08), and a lower risk of death (HR, 0.55; 95% CI, 0.33-0.92). At 1 year, no differences were found in the risk of severe hypoglycemia events, severe hyperglycemia events, or death and no difference in change in HbA1c level was found among those who did vs did not receive intensifications (mean postdischarge HbA1c, 7.72% vs 7.70%; difference-in-differences, 0.02%; 95% CI, -0.12% to 0.16%). At 1 year, 48.0% (591 of 1231) of new oral diabetes medications and 38.5% (548 of 1423) of new insulin prescriptions filled at discharge were no longer being filled.

CONCLUSIONS AND RELEVANCE

In this national cohort study, among older adults hospitalized for common medical conditions, discharge with intensified diabetes medications was associated with an increased short-term risk of severe hypoglycemia events but was not associated with reduced severe hyperglycemia events or improve HbA1c control. These findings indicate that short-term hospitalization may not be an effective time to intervene in long-term diabetes management.

Deprescribing Blood Pressure Treatment in Long-Term Care Residents

OBJECTIVES

To evaluate the incidence of deprescribing of antihypertensive medication among older adults residing in Veterans Affairs (VA) nursing homes for long-term care and rates of deprescribing after potentially triggering events.

DESIGN

Retrospective cohort study.

SETTING AND PARTICIPANTS

Long-term care residents aged 65 years and older admitted to a VA nursing home from 2006 to 2019 and using blood pressure medication at admission.

METHODS

Data were extracted from the VA electronic health record, and Centers for Medicare & Medicaid Services Minimum Data Set and Bar Code Medication Administration. Deprescribing was defined on a rolling basis as a reduction in the number or dose of antihypertensive medications, sustained for ≥2 weeks. We examined potentially triggering events for deprescribing, including low blood pressure (<90/60 mmHg), acute renal impairment (creatinine increase of 50%), electrolyte imbalance (potassium below 3.5 mEq/L, sodium decrease by 5 mEq/L), and falls.

RESULTS

Among 31,499 VA nursing home residents on antihypertensive medication, 70.4% had ≥1 deprescribing event (median length of stay = 6 months), and 48.7% had a net reduction in antihypertensive medications over their stay. Deprescribing events were most common in the first 4 weeks after admission and the last 4 weeks of life. Among potentially triggering events, a 50% increase in serum creatinine was associated with the greatest increase in the likelihood of deprescribing over the subsequent 4 weeks: residents with this event had a 41.7% chance of being deprescribed compared with 11.5% in those who did not (risk difference = 30.3%, P < .001). A fall in the past 30 days was associated with the smallest magnitude increased risk of deprescribing (risk difference = 3.8%, P < .001) of the events considered.

CONCLUSIONS AND IMPLICATIONS

Deprescribing of antihypertensive medications is common among VA nursing home residents, especially after a potential renal adverse event.

Predicting Life Expectancy Using Veterans Affairs Electronic Health Record Data

Electronic health records (EHRs) are a rich source of health data that could be used to create individualized life expectancy predictions to aid in clinical decision-making for long-term preventative treatments, such as cancer screening. Few previous studies have incorporated all possible predictors from the EHR. We aimed to screen and incorporate a large number of possible predictors from EHR data into a life expectancy (LE) prediction equation. Using the national Veteran’s Affairs (VA) EHR databases, we identified all patients aged 50+ with a primary care visit during 2005 and assessed demographics, diseases, medications, laboratory results, healthcare utilization, and vital signs during the one year prior to the visit. Mortality follow-up was complete through 2017. We used an 80% random sample for model development and a 20% random sample for model validation. We used a Gompertz survival model with backwards selection to identify approximately 100 variables for the final LE prediction equation. In 1,263,595 VA patients, the mean age was 68 years and the majority were male (94%) and white (87%). During 12 years of follow-up, 602,576 (47.7%) died. Of 930 predictors from the EHR, 99 were included in the LE prediction equation. Harrell’s C-statistic was 0.7705 (95%CI: 0.7693, 0.7718). The model estimated 10-year life expectancy with sensitivity of 81.6% (81.4%, 81.8%) and specificity of 68.8% (68.5%, 69.1%). In conclusion, we developed an LE prediction equation from hundreds of predictors in the VA EHR with good discrimination and calibration that may help clinicians weigh the potential benefit of long-term preventative treatments.

A Wasteful and Harmful Practice: Sliding Scale Insulin Use Among Nursing Home Veterans

The American Medical Directors Association and the American Diabetes Association discourage the use of sliding scale insulin (SSI) in nursing home residents with diabetes due to its association with hypoglycemia, hyperglycemia, nursing burden, and patient discomfort. However, prevalence of SSI use is unclear. We used Veterans Affairs (VA) data from October 2013 to September 2016 to determine the weekly prevalence of SSI among 22,847 veterans with diabetes admitted to VA nursing homes (NHs). Average age was 75.3 (SD 8.3) years, mean A1c was 7.3% (SD 1.6%) and 57% were admitted from hospital. We first identified residents receiving any short-acting insulin. We then classified short-acting insulin use into three mutually exclusive regimens: (1) fixed scheduled doses, (2) SSI, defined as a variable dose of short-acting insulin without a concurrent fixed dose or (3) bolus with correction (BWC), defined as a variable dose given concurrently with a fixed dose that day. During the first week of NH admission, 64.7% of residents with diabetes received no short-acting insulin, 7.4% received fixed scheduled doses, 6.3% received BWC and 21.4% were on SSI. At week 12, the prevalence of fixed dose and BWC regimens was unchanged from baseline (fixed dose = 8.4%; BWC = 7.0%). In contrast, the prevalence of SSI decreased weekly to 15.8% (p for linear trend < 0.0001). Although SSI prevalence decreased from week 1 to week 12, 51% of residents on short-acting insulin were still using SSI in their 12th week of their NH stay.

Role of carbon nanoparticle suspension in sentinel lymph node biopsy for early-stage cervical cancer: a prospective study

OBJECTIVE

To evaluate the clinical diagnostic validity of carbon nanoparticle suspension (CNS) in sentinel lymph node biopsy (SLNB) for assessing lymphatic spread of early-stage cervical cancer.

DESIGN

A prospective study.

SETTING AND POPULATION

356 cases.

METHODS

We enrolled 356 stage Ia2-IIa2 cervical cancer patients to undergo SLNB using CNS, followed by systematic pelvic lymphadenectomy. All lymph node specimens were assessed using conventional histopathologic ± pathologic ultrastaging analyses.

MAIN OUTCOME MEASURES

Sentinel lymph node detection rate (DR), clinical diagnostic validity and various related factors were analysed.

RESULTS

CNS identified 1456 SLNs in 325 patients. The overall SLN DR was 91.29%. A significantly higher DR was found for patients with tumours <20 mm (97.75% versus 71.91%; P < 0.001). Two patients had false-negative results. SLNB with CNS had sensitivity of 96.65%, false-negative rate (FNR) of 4.35% and negative predictive value (NPV) of 99.29%. Importantly, sensitivity (100%), NPV (100%) and FNR (0%) were improved when testing the subgroup of patients with tumours <20 mm (267 cases). There were no observed differences in DR based on pathological type or grade, stage, depth of stromal invasion, surgical approach, menopausal status or prior treatment with chemotherapy (P > 0.05).

CONCLUSIONS

Sentinel lymph node biopsy with CNS results in favourable DR, sensitivity and NPV for women with early-stage cervical cancer with small tumour sizes. SLNB with CNS is safe, feasible and relatively effective for guiding precise surgical treatment of early-stage cervical cancer.

TWEETABLE ABSTRACT

Sentinel lymph node biopsy with carbon nanoparticle suspension is safe and feasible for early-stage cervical cancer.

Association of Functional, Cognitive, and Psychological Measures With 1-Year Mortality in Patients Undergoing Major Surgery

Importance

More older adults are undergoing major surgery despite the greater risk of postoperative mortality. Although measures, such as functional, cognitive, and psychological status, are known to be crucial components of health in older persons, they are not often used in assessing the risk of adverse postoperative outcomes in older adults.

Objective

To determine the association between measures of physical, cognitive, and psychological function and 1-year mortality in older adults after major surgery.

Design, Setting, and Participants

Retrospective analysis of a prospective cohort study of participants 66 years or older who were enrolled in the nationally representative Health and Retirement Study and underwent 1 of 3 types of major surgery.

Exposures

Major surgery, including abdominal aortic aneurysm repair, coronary artery bypass graft, and colectomy.

Main Outcomes and Measures

Our outcome was mortality within 1 year of major surgery. Our primary associated factors included functional, cognitive, and psychological factors: dependence in activities of daily living (ADL), dependence in instrumental ADL, inability to walk several blocks, cognitive status, and presence of depression. We adjusted for other demographic and clinical predictors.

Results

Of 1341 participants, the mean (SD) participant age was 76 (6) years, 737 (55%) were women, 99 (7%) underwent abdominal aortic aneurysm repair, 686 (51%) coronary artery bypass graft, and 556 (42%) colectomy; 223 (17%) died within 1 year of their operation. After adjusting for age, comorbidity burden, surgical type, sex, race/ethnicity, wealth, income, and education, the following measures were significantly associated with 1-year mortality: more than 1 ADL dependence (29% vs 13%; adjusted hazard ratio [aHR], 2.76; P = .001), more than 1 instrumental ADL dependence (21% vs 14%; aHR, 1.32; P = .05), the inability to walk several blocks (17% vs 11%; aHR, 1.64; P = .01), dementia (21% vs 12%; aHR, 1.91; P = .03), and depression (19% vs 12%; aHR, 1.72; P = .01). The risk of 1-year mortality increased within the increasing risk factors present (0 factors: 10.0%; 1 factor: 16.2%; 2 factors: 27.8%).

Conclusions and Relevance

In this older adult cohort, 223 participants (17%) who underwent major surgery died within 1 year and poor function, cognition, and psychological well-being were significantly associated with mortality. Measures in function, cognition, and psychological well-being need to be incorporated into the preoperative assessment to enhance surgical decision-making and patient counseling.

Prevalence of Diabetes Medication Intensifications in Older Adults Discharged From US Veterans Health Administration Hospitals

Importance

Elevated blood glucose levels are common in hospitalized older adults and may lead clinicians to intensify outpatient diabetes medications at discharge, risking potential overtreatment when patients return home.

Objective

To assess how often hospitalized older adults are discharged with intensified diabetes medications and the likelihood of benefit associated with these intensifications.

Design, Setting, and Participants

This retrospective cohort study examined patients aged 65 years and older with diabetes not previously requiring insulin. The study included patients who were hospitalized in a Veterans Health Administration hospital for common medical conditions between 2011 and 2013.

Main Outcomes and Measures

Intensification of outpatient diabetes medications, defined as receiving a new or higher-dose medication at discharge than was being taken prior to hospitalization. Mixed-effect logistic regression models were used to control for patient and hospitalization characteristics.

Results

Of 16 178 patients (mean [SD] age, 73 [8] years; 15 895 [98%] men), 8535 (53%) had a preadmission hemoglobin A1c (HbA1c) level less than 7.0%, and 1044 (6%) had an HbA1c level greater than 9.0%. Overall, 1626 patients (10%) were discharged with intensified diabetes medications including 781 (5%) with new insulins and 557 (3%) with intensified sulfonylureas. Nearly half of patients receiving intensifications (49% [791 of 1626]) were classified as being unlikely to benefit owing to limited life expectancy or already being at goal HbA1c, while 20% (329 of 1626) were classified as having potential to benefit. Both preadmission HbA1c level and inpatient blood glucose recordings were associated with discharge with intensified diabetes medications. Among patients with a preadmission HbA1c level less than 7.0%, the predicted probability of receiving an intensification was 4% (95% CI, 3%-4%) for patients without elevated inpatient blood glucose levels and 21% (95% CI, 15%-26%) for patients with severely elevated inpatient blood glucose levels.

Conclusions and Relevance

In this study, 1 in 10 older adults with diabetes hospitalized for common medical conditions was discharged with intensified diabetes medications. Nearly half of these individuals were unlikely to benefit owing to limited life expectancy or already being at their HbA1c goal.

GERIATRIC MEASURES AS PREDICTORS OF 1-YEAR MORTALITY IN MAJOR SURGERY PATIENTS

A growing proportion of older adults are undergoing major surgery despite the higher risk of post-operative mortality. Geriatric measures (i.e. physical, cognitive, and psychosocial function) are often not included in studies evaluating post-operative outcomes in older adults. Our goal was to determine the association of geriatric measures and 1-year mortality in older adults after major surgery. We analyzed longitudinal data from the Health and Retirement Study linked to Medicare claims (N=1364 participants), age ≥ 65 and who underwent abdominal aortic aneurysm [AAA] repair, coronary artery bypass graft [CABG], or colectomy. Our outcome was mortality within 1 year of the major operation. Predictors included the following geriatric measures: dependence in activities of daily living (ADL), dependence in independent activities of daily living (IADL), mobility ability, and dementia, and depression. We analyzed using multivariate cox proportional hazard models. Mean participant age was 76±6 years, 56% were women, 11% underwent a AAA repair, 50% CABG, 40% colectomy; 18% died within 1 year of their major operation. After adjusting for age, comorbidity burden, surgical type, gender, race, wealth, income, and education, the following measures were significantly associated with 1-year mortality: depression (adjusted HR (aHR): 1.53, p=0.03), dementia (aHR: 1.90, p=0.03), >1 ADL dependence (aHR: 2.35, p<0.01), >1 IADL dependence (aHR: 1.95, p<0.01), and inability to walk several blocks (aHR: 1.69, p<0.01). In this cohort, 18% of participants who underwent major surgery died within 1 year and function, cognition, and psychological well-being were significantly associated with mortality. These measures should be incorporated into pre-operative assessment.

Clinical Outcomes After Intensifying Antihypertensive Medication Regimens Among Older Adults at Hospital Discharge

IMPORTANCE

Transient elevations of blood pressure (BP) are common in hospitalized older adults and frequently lead practitioners to prescribe more intensive antihypertensive regimens at hospital discharge than the patients were using before hospitalization.

OBJECTIVE

To investigate the association between intensification of antihypertensive regimens at hospital discharge and clinical outcomes after discharge.

DESIGN, SETTING, AND PARTICIPANTS

In this retrospective cohort study, patients 65 years and older with hypertension who were hospitalized in Veterans Health Administration national health system facilities from January 1, 2011, to December 31, 2013, for common noncardiac conditions were studied. Data analysis was performed from October 1, 2018, to March 10, 2019.

EXPOSURES

Discharge with antihypertensive intensification, defined as receiving a prescription at hospital discharge for a new or higher-dose antihypertensive than was being used before hospitalization. Propensity scores were used to construct a matched-pairs cohort of patients who did and did not receive antihypertensive intensifications at hospital discharge.

MAIN OUTCOMES AND MEASURES

The primary outcomes of hospital readmission, serious adverse events, and cardiovascular events were assessed by competing risk analysis. The secondary outcome was the change in systolic BP within 1 year of hospital discharge.

RESULTS

The propensity-matched cohort included 4056 hospitalized older adults with hypertension (mean [SD] age, 77 [8] years; 3961 men [97.7%]), equally split between those who did vs did not receive antihypertensive intensifications at hospital discharge. Groups were well matched on all baseline covariates (all standardized mean differences <0.1). Within 30 days, patients receiving intensifications had a higher risk of readmission (hazard ratio [HR], 1.23; 95% CI, 1.07-1.42; number needed to harm [NNH], 27; 95% CI, 16-76) and serious adverse events (HR, 1.41; 95% CI, 1.06-1.88; NNH, 63; 95% CI, 34-370). At 1 year, no differences were found in cardiovascular events (HR, 1.18; 95% CI, 0.99-1.40) or change in systolic BP among those who did vs did not receive intensifications (mean BP, 134.7 vs 134.4; difference-in-differences estimate, 0.6 mm Hg; 95% CI, -2.4 to 3.7 mm Hg).

CONCLUSIONS AND RELEVANCE

Among older adults hospitalized for noncardiac conditions, prescription of intensified antihypertensives at discharge was not associated with reduced cardiac events or improved BP control within 1 year but was associated with an increased risk of readmission and serious adverse events within 30 days.

Comparison of Pharmacy Database Methods for Determining Prevalent Chronic Medication Use

BACKGROUND

Pharmacy dispensing data are frequently used to identify prevalent medication use as a predictor or covariate in observational research studies. Although several methods have been proposed for using pharmacy dispensing data to identify prevalent medication use, little is known about their comparative performance.

OBJECTIVES

The authors sought to compare the performance of different methods for identifying prevalent outpatient medication use.

RESEARCH DESIGN

Outpatient pharmacy fill data were compared with medication reconciliation notes denoting prevalent outpatient medication use at the time of hospital admission for a random sample of 207 patients drawn from a national cohort of patients admitted to Veterans Affairs hospitals. Using reconciliation notes as the criterion standard, we determined the test characteristics of 12 pharmacy database algorithms for determining prevalent use of 11 classes of cardiovascular and diabetes medications.

RESULTS

The best-performing algorithms included a 180-day fixed look-back period approach (sensitivity, 93%; specificity, 97%; and positive predictive value, 89%) and a medication-on-hand approach with a grace period of 60 days (sensitivity, 91%; specificity, 97%; and positive predictive value, 91%). Algorithms that have been commonly used in previous studies, such as defining prevalent medications to include any medications filled in the prior year or only medications filled in the prior 30 days, performed less well. Algorithm performance was less accurate among patients recently receiving hospital or nursing facility care.

CONCLUSION

Pharmacy database algorithms that balance recentness of medication fills with grace periods performed better than more simplistic approaches and should be considered for future studies which examine prevalent chronic medication use.

Intensification of older adults' outpatient blood pressure treatment at hospital discharge: national retrospective cohort study

OBJECTIVES

To assess how often older adults admitted to hospital for common non-cardiac conditions were discharged with intensified antihypertensive treatment, and to identify markers of appropriateness for these intensifications.

DESIGN

Retrospective cohort study.

SETTING

US Veterans Administration Health System.

PARTICIPANTS

Patients aged 65 years or over with hypertension admitted to hospital with non-cardiac conditions between 2011 and 2013.

MAIN OUTCOME MEASURES

Intensification of antihypertensive treatment, defined as receiving a new or higher dose antihypertensive agent at discharge compared with drugs used before admission. Hierarchical logistic regression analyses were used to control for characteristics of patients and hospitals.

RESULTS

Among 14 915 older adults (median age 76, interquartile range 69-84), 9636 (65%) had well controlled outpatient blood pressure before hospital admission. Overall, 2074 (14%) patients were discharged with intensified antihypertensive treatment, more than half of whom (1082) had well controlled blood pressure before admission. After adjustment for potential confounders, elevated inpatient blood pressure was strongly associated with being discharged on intensified antihypertensive regimens. Among patients with previously well controlled outpatient blood pressure, 8% (95% confidence interval 7% to 9%) of patients without elevated inpatient blood pressure, 24% (21% to 26%) of patients with moderately elevated inpatient blood pressure, and 40% (34% to 46%) of patients with severely elevated inpatient blood pressure were discharged with intensified antihypertensive regimens. No differences were seen in rates of intensification among patients least likely to benefit from tight blood pressure control (limited life expectancy, dementia, or metastatic malignancy), nor in those most likely to benefit (history of myocardial infarction, cerebrovascular disease, or renal disease).

CONCLUSIONS

One in seven older adults admitted to hospital for common non-cardiac conditions were discharged with intensified antihypertensive treatment. More than half of intensifications occurred in patients with previously well controlled outpatient blood pressure. More attention is needed to reduce potentially harmful overtreatment of blood pressure as older adults transition from hospital to home.

Hypoglycemia in Hospice Patients With Type 2 Diabetes in a National Sample of Nursing Homes

This retrospective cohort study examines whether patients with type 2 diabetes on hospice are assessed for dysglycemia, receive insulin or oral hypoglycemic medications, or experience hypoglycemia and hyperglycemia in the nursing home setting.

Appropriate dose of Lactobacillus buchneri supplement improves intestinal microbiota and prevents diarrhoea in weaning Rex rabbits

This study examined the effects on intestinal microbiota and diarrhoea of Lactobacillus buchneri supplementation to the diet of weaning Rex rabbits. To this end, rabbits were treated with L. buchneri at two different doses (LC: 104 cfu/g diet and HC: 105 cfu/g diet) for 4 weeks. PCR-DGGE was used to determine the diversity of the intestinal microbiota, while real-time PCR permitted the detection of individual bacterial species. ELISA and real-time PCR allowed the identification of numerous cytokines in the intestinal tissues. Zonula occludens-1, polymeric immunoglobulin receptor and immunoglobulin A genes were examined to evaluate intestinal barriers. Results showed that the biodiversity of the intestinal microbiota of weaning Rex rabbits improved in the whole tract of the treated groups. The abundance of most detected bacterial species was highly increased in the duodenum, jejunum and ileum after L. buchneri administration. The species abundance in the HC group was more increased than in the LC group when compared to the control. Although the abundance of Enterobacteriaceae exhibited a different pattern, Escherichia coli was inhibited in all treatment groups. Toll-like receptor (TLR)2 and TLR4 genes were down-regulated in all intestinal tissues as the microbiota changed. In the LC group, the secretion of the inflammatory cytokine tumour necrosis factor-α was reduced, the gene expression of the anti-inflammatory cytokine interleukin (IL)-4 was up-regulated and the expression of intestinal-barrier-related genes was enhanced. Conversely, IL-4 expression was increased and the expression of other tested genes did not change in the HC group. The beneficial effects of LC were greater than those of HC or the control in terms of improving the daily weight gain and survival rate of weaning Rex rabbits and reducing their diarrhoea rate. Therefore, 104 cfu/g L. buchneri treatment improved the microbiota of weaning Rex rabbits and prevented diarrhoea in these animals.

Estimated GFR Before and After Bariatric Surgery in CKD

BACKGROUND

Several reviews have recently detailed the beneficial effects of weight loss surgery for kidney function. However, these studies have a number of limitations, including small sample size, few done in chronic kidney disease (CKD) stages 3 and 4, and many not including the main bariatric surgery procedures used in the United States today.

STUDY DESIGN

This was an observational retrospective cohort study comparing propensity score-matched bariatric surgery patients and nonsurgery control patients who were referred for, but did not have, surgery. Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy were also compared using propensity matching.

SETTING & PARTICIPANTS

Patients (714 surgery patients; 714 controls) were from a large integrated health care system, a mean of 58±8 (SD) years old, and mostly women (77%) and non-Hispanic whites (56%) and had diabetes mellitus (66%) and/or hypertension (91%).

PREDICTOR

Predictors at the time of surgery or referral to surgery were age, sex, race/ethnicity, weight, and presence of diabetes and/or hypertension.

OUTCOMES

The primary outcome for this study was change in estimated glomerular filtration rate (eGFR) from serum creatinine level over a median 3-year follow-up period.

MEASUREMENTS

Serum creatinine was used to calculate eGFR using the CKD-EPI (CKD Epidemiology Collaboration) creatinine equation.

RESULTS

Surgery patients had 9.84 (95% CI, 8.05-11.62) mL/min/1.73m² greater eGFRs than controls at a median 3 years' follow-up and RYGB patients had 6.60 (95% CI, 3.42-9.78) mL/min/1.73m² greater eGFRs than sleeve gastrectomy patients during the same period.

LIMITATIONS

This study is limited by its nonrandomized observational study design, estimation of GFR, and large changes in muscle mass, which may affect serum creatinine level independent of changes in kidney function.

CONCLUSIONS

Bariatric surgery, especially the RYGB procedure, results in significant improvements for up to 3 years in eGFRs for patients with CKD stages 3 and 4.

[Non-Invasive Diagnosis of Ocular Graft-versus-Host Disease]

Ocular graft-vs-host disease (GvHD) is a major complication following allogenic blood stem cell transplantation (aBSCT) leading to a disturbance of the ocular surface integrity with a broad range of severity. Leading symptom is a pronounced autoinflammatory reaction in particular at the ocular surface with typical features of dry eye disease. Potential complications include visual loss, pain and damage to the ocular structures with, e. g. corneal ulcerations. Diagnosis and treatment of ocular GvHD are a challenge for attending ophthalmologists and require intensive interdisciplinary patient care in particular with haemato-oncologists. First and follow-up examinations consist of several diagnostic steps that include quantitative and qualitative analysis of tearfilm, visual acuity, ocular surface and retinal integrity, cataract development and subjective symptoms. Available tests are mostly evaluated for usage in dry eye diagnosis but are, however, mostly unspecific for diagnosing ocular GvHD reliably. Only combinations of several clinical tests together with the experience of specialised ophthalmologists may lead to the certain diagnosis and treatment decisions at state. This review illustrates the available established and innovative non-invasive diagnostic tests and evaluates their potential use for diagnosing ocular GvHD.

[Analysis of nuclear DNA gene types of Leishmania isolates from hilly and plain foci of China]

AIM

To analyse the nuclear DNA (nDNA) polymorphism of Leishmania isolates from hilly and plain foci of China.

METHODS

nDNA were analysed by endonuclease digestion, Southern blotting and chromosomal localization. Probes were labeled with digoxigenin.

RESULTS

Using gp63 gene probe, similar hybridization bands were found to be existed between nDNAs of Leishmania donovani Jiangsu human isolate and L. d. Jeddah, also between nDNAs of L. d. Sichuan human isolate and L. infantum. Using beta-tubulin gene probe, there were two similar hybridization bands existed between nDNAs of L. d. Jiangsu human isolate and L. d. Jeddah, and three similar hybridization bands existed between nDNAs of L. d. Sichuan canine isolate and L. d. Gansu canine isolate, and two similar hybridization bands existed between nDNA of L. d. Sichuan canine isolate and L. d. Wenchuan human isolate.

CONCLUSION

Homology exists between L. d. Jiangsu human isolate and L. d. Jeddah from plain foci, between L. d. Sichuan human isolate from hilly foci and L. infantum, between L. d. Sichuan canine isolate and L. d. Gansu canine isolate from hilly foci. Homology as well as differences exist between L. d. Sichuan canine isolate and L. d. Wenchuan human isolate. Heterogeneity exists between isolates from hilly foci and plain foci.

Medial axis reformation: a new visualization method for CT angiography

RATIONALE AND OBJECTIVES

The authors performed this study to evaluate a new method (medial axis reformation [MAR]) for visualizing three-dimensional vascular data at electron-beam computed tomographic (CT) angiography.

MATERIALS AND METHODS

MAR was performed automatically with a personal computer-based workstation. After the region of interest was edited, voxels were divided into groups according to their path lengths. Centroids of groups were connected to form the medial axis. Then, the medial axis was refined with multiscale medial response. Bifurcations were also detected and refined. Finally, curved sections were generated through the branches and laid out onto a single image by using a splitting method. The authors performed MAR during electron-beam CT angiography of coronary arteries, common carotid arteries, and iliac arteries.

RESULTS

MAR displayed curved sections of branched vessels on one image, cut through the axis of vessels to show the vessel diameter objectively, and allowed the viewing direction to be altered arbitrarily.

CONCLUSION

Results of preliminary applications demonstrate that MAR is a valuable new visualization method for CT angiography.

Evaluation of coronary artery bypass graft patency using three-dimensional reconstruction and flow study of electron beam tomography

OBJECTIVE

To establish and evaluate two protocols for the noninvasive visualization and assessment of coronary artery bypass graft (CABG) patency on electron beam tomography (EBT).

METHODS

Two hundred and fourteen consecutive patients who underwent coronary artery bypass graft surgery were scanned using both EBT angiography with 3-dimensional reconstruction and EBT flow study with time-density-curve analysis.

RESULTS

There were 589 CABGs evaluated in this study (10 grafts were excluded because of artifacts). Among them, 133 (98.5%) of 135 arterial grafts were patent, and 345 (77.7%) of 444 saphenous-vein grafts were patent. Within 5 years or between 5 and 10 years after operation, arterial graft patency exceeded venous graft patency (P < 0.001). Three-dimensional EBT angiography achieved higher sensitivity, specificity and accuracy (97.7%, 94.1% and 96.7%, respectively) than did EBT flow study (88.4%, 82.4% and 85.2%, respectively) for evaluating occlusion or patency of CABG. The intra-graft flow of patent arterial and venous grafts were 4.9 +/- 2.2 ml.min-1.g-1 and 6.9 +/- 2.8 ml.min-1.g-1, respectively (P < 0.001).

CONCLUSION

The combination of EBT three-dimensional reconstruction and flow study can be more effective in the assessment of CABG anatomy and quantification of patent CABG blood flow.

[Effect of rhubarb on oxygen radicals leakage from mitochondria of intestinal mucosa in burned rats]

OBJECTIVE

To investigate the effects of rhubarb on oxygen radicals leakage from the mitochondria of intestinal mucosa in burned rats.

METHODS

The activity of cytochrome oxidase and superoxide dismutase (SOD) in mitochondria isolated from intestinal mucosa of burn model of rats was used to evaluate the oxygen radicals leakage from the mitochondria. And the SOD and malondialdehyde (MDA) levels in plasma, liver, intestinal mucosa and its mitochondria were also determined.

RESULTS

After burn injury, the activity of cytochrome oxidase in intestinal mucosa decreased as the time elapses, rhubarb could improve it obviously. Furthermore, rhubarb could reduce the massive consumption of SOD and production of MDA obviously increased in plasma, liver, intestinal mucosa and its mitochondria after burning.

CONCLUSION

Rhubarb could enhance the activity of cytochrome oxidase and SOD in small intestine mucosal epithelia in burned rats, thus the oxygen radicals leakage from the mitochondria to be reduced.

Evaluation of electron beam tomographic coronary arteriography with three-dimensional reconstruction in healthy subjects

In this study, the authors evaluated the performance characteristics of contrast-enhanced electron-beam tomography (EBT) with three-dimensional reconstruction in defining the coronary artery lumen in healthy subjects. Thirty patients with normal coronary angiograms by selective coronary arteriography (SCA) underwent contrast-enhanced EBT examination. Measured parameters included degree of luminal enhancement, intravascular contrast-to-noise ratio (CNR), and diameter and length of visualized lumen. Ventricular cavity, aortic blood pool, and coronary artery attenuation were found to be significantly different before and after intravenous injection of contrast material (p < 0.001). CNR decreased from proximal to distal segments within each vessel (p < 0.001), with a peak of 11.2 +/- 2.3 occurring in the proximal left anterior descending coronary artery (LAD) to a low of 4.8 +/- 2.0 in the distal left circumflex (LCX). Luminal diameters visualized by EBT had no significant difference with that of SCA (p > 0.05). Therefore, EBT angiography with three-dimensional reconstruction allows for noninvasive coronary arteriography revealing long segments of the major coronary arteries in normal subjects.