Pre-hospitalization dysphagia and feeding tube placement in nursing home residents with advanced dementia

BACKGROUND

Despite research demonstrating the risks of using feeding tubes in persons with advanced dementia, they continue to be placed. The natural history of dysphagia among patients with advanced dementia has not been examined. We conducted a secondary analysis of a national cohort of persons with advanced dementia staying at a nursing home stay before hospitalization to examine (1) pre-hospitalization dysphagia prevalence and (2) risk of feeding tube placement during hospitalization based on preexisting dysphagia.

METHODS

A retrospective cohort study consisting of all nursing home (NH) residents (≥66 years) with advanced dementia (Cognitive Function Scale score ≥2), a hospitalization between 2013-2017, and a Minimum Data Set (MDS) 3.0 assessment within 120 days before hospitalization. Pre-hospitalization dysphagia status and surgically placed feeding tube insertion during hospitalization were determined by MDS 3.0 swallowing items and ICD-9 codes, respectively. A multivariate logistic model clustering on hospital was used to examine the association of dysphagia with percutaneous endoscopic gastrostomy (PEG) feeding tube placement after adjustment for confounders.

RESULTS

Between 2013 and 2017, 889,983 persons with NH stay with advanced dementia (mean age: 84.5, SD: 7.5, and 63.5% female) were hospitalized. Pre-hospitalization dysphagia was documented in 5.4% (n = 47,574) and characterized by oral dysphagia (n = 21,438, 2.4%), pharyngeal dysphagia (n = 24,257, 2.7%), and general swallowing complaints/pain (n = 14,928, 1.7%). Overall, PEG feeding tubes were placed in 3529 patients (11.2%) with pre-hospitalization dysphagia, whereas 27,893 (88.8%) did not have pre-hospitalization dysphagia according to MDS 3.0 items. Feeding tube placement risk increased with the number of dysphagia items noted on the pre-hospitalization MDS (6 vs. 0 dysphagia variables: OR = 5.43, 95% CI: 3.19-9.27).

CONCLUSIONS

Based on MDS 3.0 assessment, only 11% of PEG feeding tubes were inserted in persons with prior dysphagia. Future research is needed on whether this represents inadequate assessment or the impact of potentially reversible intercurrent illness resulting in feeding tube placement.

Comparison of the Pathway to Hospice Enrollment Between Medicare Advantage and Traditional Medicare

Importance

Older adults in Medicare Advantage (MA) enroll in hospice at higher rates than those in traditional Medicare (TM), but it is unclear whether the pathway of care prior to hospice use differs between MA and TM.

Objective

To examine the site of care prior to hospice enrollment for MA beneficiaries compared with those in TM.

Design, Setting, and Participants

This population-based, retrospective cross-sectional study used Medicare claims data for decedents in calendar years 2011, 2013, 2016, and 2018 who enrolled in hospice in the last 90 days of life. Data were analyzed from February 11, 2022, to October 24, 2022.

Exposures

Enrollment in MA or TM in the last month of life.

Main Outcomes and Measures

The main outcome was the site of care prior to hospice enrollment, defined as hospital, nursing home, and home with or without home health, dichotomized as community vs hospital in a logistic regression model. Covariates included decedent demographics, hospice primary diagnosis, and county-level MA penetration. Differences in hospice length of stay between MA beneficiaries and TM beneficiaries were assessed using linear and logistic regression models.

Results

In this study of 3 164 959 decedents, mean (SD) age was 83.1 (8.6) years, 55.8% were female, and 28.8% were enrolled in MA. Decedents in MA were more likely to enroll in hospice from a community setting than were those in TM, although the gap narrowed over time from an unadjusted 11.1% higher rate of community enrollment in MA vs TM in 2011 (50.1% vs 39.0%) to 8.1% in 2018 (46.4% vs 38.3%). In the primary adjusted analysis over the entire study period, MA enrollment was associated with an 8.09-percentage point (95% CI, 7.96-8.21 percentage points) higher rate of hospice enrollment from the community vs all other sites. This association remained in multiple sensitivity analyses to account for potential differences in the populations enrolled in MA vs TM. The mean overall hospice length of stay was 0.29 days (95% CI, 0.24-0.34 days) longer for MA decedents compared with TM decedents.

Conclusions and Relevance

Compared with TM beneficiaries, those in MA were more likely to enroll in hospice from community settings vs following inpatient stays. However, hospice length of stay was not substantially different between MA and TM. Further research is needed to understand how MA plans influence hospice use and the direct association with quality of end-of-life care as reported by older adults and their families.

DYSPHAGIA FOLLOWING HOSPITALIZATION IN NURSING HOME RESIDENTS WITH ALZHEIMER’S DISEASE AND RELATED DEMENTIAS

Dysphagia frequently occurs in nursing home (NH) residents with Alzheimer’s Disease and Related Dementias (ADRD), often leading to serious health outcomes (e.g., pneumonia, malnutrition, reduced quality of life). While it is known that hospitalized NH residents with ADRD experience high rates of iatrogenic complications, dysphagia following discharge has not been examined. A retrospective cohort of all NH residents in the US (older adults aged ≥66) with advanced ADRD (Cognitive Function Scale ≥2), hospitalized between 2013-2017, and without a feeding tube or reported dysphagia on a Minimum Data Set (MDS) 3.0 assessment within 120 days prior to hospitalization was constructed. Treatment with intermittent mandatory ventilation (IMV) or non-invasive ventilation (NIV) during hospitalization and dysphagia status on the first post-hospitalization MDS was recorded. Data were analyzed using descriptive statistics and random effects multivariate logistic models that adjusted for age, gender, race/ethnicity, CFS score, ADL score, and comorbidities. Among the 805,199 residents with ADRD who survived the hospitalization and returned to the NH, new onset dysphagia occurred in 53,807 (6.7%; 95% CI 6.6-6.7) of residents. After adjustment, invasive mechanical ventilation (IMV) use was associated with increased risk of new onset of dysphagia (AOR 1.5; 95% CI 1.4-1.6) and non-invasive mechanical ventilation (NIMV) only slightly increased the risk (AOR 1.3; 95% 1.2-1.3). NH residents with ADRD are at risk for dysphagia following hospitalization. These findings emphasize the importance of swallowing evaluation and dysphagia treatment during hospitalization for ADRD patients, especially those treated with IMV or NIV, to prevent further negative health outcomes.

Pathway to Hospice: How Has Place of Care before Hospice Changed with the Growth of Hospice in the United States?

Background: Hospice use among Medicare decedents increased from 21.6% in 2000 to 51.6% in 2019. Whether this growth has been accompanied by more referrals to hospice directly from the community is not known. Objective: To assess trends in place of care before hospice enrollment. Design: Retrospective cohort from 2011 to 2018. Subjects: Medicare decedents age ≥66 years. Measure: Location of care before hospice enrollment in the last 90 days of life, defined as: the community with and without home health, short- or long-term nursing facility, or inpatient hospital. A county-level random effects model examined changes in enrollment from the community after adjusting for admitting diagnosis, age, race/ethnicity, sex, and Medicaid participation. Results: Among hospice enrollees (N = 7,650,933), 27.7% transitioned to hospice from the community, 31.8% transitioned from the hospital, and 10.1% transitioned after short- or long-term nursing facility stay. Rates of enrollment to hospice from the community remained stable from 35.1% in 2011 to 34.3% in 2018. After adjustment, the proportion enrolling in hospice from the community decreased by 1.2% (95% confidence interval -1.0% to 1.4%). Place of care before hospice enrollment in 2018 varied by hospice admitting diagnosis, with patients with cancer more likely to enroll from the community (39.5%) and patients with cerebrovascular accidents from the hospital (53.2%). Prior place of care varied by state, with Florida having the highest rate of the enrollment following hospitalization (47.8%). Conclusion: Despite the growth of hospice, the site of care before hospice enrollment has remained relatively stable and was strongly influenced by region.

Mechanical Ventilation and Survival in Patients With Advanced Dementia in Medicare Advantage

CONTEXT

Medicare Advantage (MA) cares for an increasing proportion of traditional Medicare (TM) patients although, the association of MA on low-value care among hospitalized patients is uncertain.

OBJECTIVES

We sought to determine whether invasive mechanical ventilation (IMV) use or mortality differs among hospitalized patients with advanced dementia (AD) enrolled in MA vs. TM and the influence of hospital MA concentration.

METHODS

Retrospective cohort of hospitalized Medicare patients from 2016 to 2017 who were ≥66 years old with AD (n=147,153) and had a hospitalization with an assessment completed during a nursing home stay ≤120 days prior to that hospitalization indicating AD and severe cognitive/functional impairment. MA enrollment was ascertained at hospitalization; IMV use and 30- and 365-day mortality were determined via Medicare data. Multivariable logistic regression models clustered by hospital were used.

RESULTS

Among hospitalized Medicare patients with AD, 27,253 (19%) were enrolled in MA, mean age was 84 (95% CI: 83.9-84.0) and 92,736 (63%) were female. Enrollment in MA was associated with increased IMV use (Adjusted Odds Ratio(AOR)=1.11, 95% CI: 1.04-1.18), 30- (Adjusted Hazard Ratio(AHR)=1.09, 95% CI: 1.05-1.12) and 365-day mortality (AHR=1.12, 95% CI: 1.08-1.16) compared to TM. Use of IMV was not different based on concentration of MA at the hospital level.

CONCLUSION

MA may reduce hospitalizations, however, once hospitalized, patients with AD enrolled in MA experience higher rates of IMV use and worse 30- and 365-day mortality compared to TM patients. Higher hospital concentration of MA did not reduce use of IMV. MA may not offer significant benefits in reducing low-value care among patients hospitalized with serious illness, questioning the benefits of this care model.

Dementia diagnosis in the hospital and outcomes among patients with advanced dementia documented in the Minimum Data Set

BACKGROUND

Individuals with dementia do not always have a diagnosis of dementia noted on their hospital claims. Whether this lack of documentation is associated with patient outcomes is unknown. We examined the association between a dementia diagnosis listed on a hospital claim and patient outcomes among individuals with a Minimum Data Set (MDS) assessment.

METHODS

A retrospective cohort study was conducted using administrative claims data and nursing home MDS assessments. Hospitalized patients aged 66 and older with advanced dementia noted on an MDS assessment completed within 120 days prior to their first hospitalization in 2017 were included. Advanced dementia was defined based on an MDS diagnosis of dementia, dependency in four or more activities of daily living, and a Cognitive Function Scale score indicative of moderate to severe impairment. Multilevel regression with a random intercept at the hospital level was used to examine the relationship between documentation of dementia in inpatient hospital Medicare claims and the following patient outcomes after adjusting for patient and hospital characteristics: invasive mechanical ventilation (IMV) use, intensive care unit or coronary care unit (ICU/CCU) use, 30-day mortality, and hospital length of stay (LOS).

RESULTS

In 2017, among 120,989 patients with advanced dementia and a nursing home stay, 90.57% had a dementia diagnosis on their hospital claims. In adjusted models, documentation of a dementia diagnosis was associated with lower use of the ICU/CCU (adjusted odds ratio [AOR]: 0.78 [95% confidence interval 0.74, 0.81]), use of IMV (AOR: 0.50 [0.47, 0.54]), and 30-day mortality (AOR: 0.81 [0.77, 0.85]). Patients with a dementia diagnosis had a shorter LOS.

CONCLUSIONS

Among patients with advanced dementia, those whose dementia diagnosis was documented on their inpatient hospital Medicare claim experienced lower use of ICU/CCU, use of IMV, lower 30-day mortality, and shorter LOS than those whose diagnosis was not documented.

Trends in Noninvasive and Invasive Mechanical Ventilation Among Medicare Beneficiaries at the End of Life

IMPORTANCE

End-of-life care is costly, and decedents often experience overtreatment or low-quality care. Noninvasive ventilation (NIV) may be a palliative approach to avoid invasive mechanical ventilation (IMV) among select patients who are hospitalized at the end of life.

OBJECTIVE

To examine the trends in NIV and IMV use among decedents with a hospitalization in the last 30 days of life.

DESIGN, SETTING, AND PARTICIPANTS

This population-based cohort study used a 20% random sample of Medicare fee-for-service beneficiaries who had an acute care hospitalization in the last 30 days of life and died between January 1, 2000, and December 31, 2017. Sociodemographic, diagnosis, and comorbidity data were obtained from Medicare claims data. Data analysis was performed from September 2019 to July 2020.

EXPOSURES

Use of NIV or IMV.

MAIN OUTCOMES AND MEASURES

Validated International Classification of Diseases, Ninth Revision, Clinical Modification or International Statistical Classification of Diseases, Tenth Revision, Clinical Modification procedure codes were reviewed to identify use of NIV, IMV, both NIV and IMV, or none. Four subcohorts of Medicare beneficiaries were identified using primary admitting diagnosis codes (chronic obstructive pulmonary disease [COPD], congested heart failure [CHF], cancer, and dementia). Measures of end-of-life care included in-hospital death (acute care setting), hospice enrollment at death, and hospice enrollment in the last 3 days of life. Random-effects logistic regression examined NIV and IMV use adjusted for sociodemographic characteristics, admitting diagnosis, and comorbidities.

RESULTS

A total of 2 470 435 Medicare beneficiaries (1 353 798 women [54.8%]; mean [SD] age, 82.2 [8.2] years) were hospitalized within 30 days of death. Compared with 2000, the adjusted odds ratio (AOR) for the increase in NIV use was 2.63 (95% CI, 2.46-2.82; % receipt: 0.8% vs 2.0%) for 2005 and 11.84 (95% CI, 11.11-12.61; % receipt: 0.8% vs 7.1%) for 2017. Compared with 2000, the AOR for the increase in IMV use was 1.04 (95% CI, 1.02-1.06; % receipt: 15.0% vs 15.2%) for 2005 and 1.63 (95% CI, 1.59-1.66; % receipt: 15.0% vs 18.2%) for 2017. In subanalyses comparing 2017 with 2000, similar trends found increased NIV among patients with CHF (% receipt: 1.4% vs 14.2%; AOR, 14.14 [95% CI, 11.77-16.98]) and COPD (% receipt: 2.7% vs 14.5%; AOR, 8.22 [95% CI, 6.42-10.52]), with reciprocal stabilization in IMV use among patients with CHF (% receipt: 11.1% vs 7.8%; AOR, 1.07 [95% CI, 0.95-1.19]) and COPD (% receipt: 17.4% vs 13.2%; AOR, 1.03 [95% CI, 0.88-1.21]). The AOR for increased NIV use was 10.82 (95% CI, 8.16-14.34; % receipt: 0.4% vs 3.5%) among decedents with cancer and 9.62 (95% CI, 7.61-12.15; % receipt: 0.6% vs 5.2%) among decedents with dementia. The AOR for increased IMV use was 1.40 (95% CI, 1.26-1.55; % receipt: 6.2% vs 7.6%) among decedents with cancer and 1.28 (95% CI, 1.17-1.41; % receipt: 5.7% vs 6.2%) among decedents with dementia. Among decedents with NIV vs IMV use, lower rates of in-hospital death (50.3% [95% CI, 49.3%-51.3%] vs 76.7% [95% CI, 75.9%-77.5%]) and hospice enrollment in the last 3 days of life (57.7% [95% CI, 56.2%-59.3%] vs 63.0% [95% CI, 60.9%-65.1%]) were observed along with higher rates of hospice enrollment (41.3% [95% CI, 40.4%-42.3%] vs 20.0% [95% CI, 19.2%-20.7%]).

CONCLUSIONS AND RELEVANCE

This study found that the use of NIV rapidly increased from 2000 through 2017 among Medicare beneficiaries at the end of life, especially among persons with cancer and dementia. The findings suggest that trials to evaluate the outcomes of NIV are warranted to inform discussions about the goals of this therapy between clinicians and patients and their health care proxies.

The Black and White of Invasive Mechanical Ventilation in Advanced Dementia

BACKGROUND/OBJECTIVES

Over the past decade, feeding tube use in nursing home residents with advanced dementia has declined by 50% among white and black patients. Little is known about whether a similar reduction has occurred in other invasive interventions, such as mechanical ventilation.

DESIGN

Retrospective cohort study.

SETTING

Acute-care hospitals in the United States.

PARTICIPANTS

Medicare beneficiaries with advanced dementia who previously resided in a nursing home and were hospitalized between 2001 and 2014 with pneumonia and/or septicemia and of either black or white race.

MEASUREMENT

Invasive mechanical ventilation (IMV), as identified by International Classification of Diseases (ICD) procedure codes. Two multivariable logistic regression models examined the association between race and the likelihood of receiving IMV, adjusting for patients' demographics, physical function, and comorbidities. A hospital fixed-effects model examined the association of race within a hospital, whereas a random-effects logistic model was used to estimate the between-hospital variation in the probability of receiving IMV and examine the overall association of race and use of IMV.

RESULTS

Between 2001 and 2014, 289,017 patients with advanced dementia were hospitalized for pneumonia or septicemia. Use of IMV increased from 3.7% to 12.1% in white patients and from 8.6% to 21.8% in blacks. Among those ventilated, 1-year mortality rates remained high, at 82.7% for whites and 84.2% for blacks dying in 2013. Compared with whites, blacks had a higher odds of receiving IMV in the fixed-effects (within-hospital) model (adjusted odds ratio (AOR) = 1.34; 95% confidence interval (CI) = 1.29-1.39) and in the random-effects (between-hospital) model (AOR = 1.46; 95% CI = 1.40-1.51).

CONCLUSION

IMV use in patients with advanced dementia has increased substantially, with black patients having a larger increase than whites, based, in part, on the hospitals where black patients receive care.

Continuity of Hospital Care and Feeding Tube Use in Cognitively Impaired Hospitalized Persons

OBJECTIVES

Hospitalists are increasingly the attending physician for hospitalized patients, and the scheduling of their shifts can affect patient continuity. For dementia patients, the impact is unknown.

DESIGN

Longitudinal study using physician billing claims between 2000 and 2014 to examine the association of continuity of care with the insertion of a feeding tube (FT).

SETTING

US hospitals.

PARTICIPANTS

Between 2000 and 2014, 166,056 hospitalizations of patients with a prior nursing home stay, advanced cognitive impairment, and impairments in four or more activities of daily living (mean age = 84.2 years; 30.4% male; 81.0% white).

MEASUREMENTS

Continuity of care measured at the hospital level with the Sequential Continuity Index (SECON; range = 0 to 100; higher score indicates higher continuity).

RESULTS

Rates of a hospitalist acting as the attending physician increased from 9.6% in 2000 to 22.6% in 2010, whereas a primary care physician with a predominant outpatient focus acting as the attending physician decreased from 50.3% in 2000 to 12.6% in 2014. Post-2010, a mixture of physician specialties increased from 55.5% to 66.4% with a reduction in hospitalists from 22.6% (2010) to 14.1% (2013). Continuity of care decreased over time with SECON dropping from 63.0 to 43.5. Adjusting for patient baseline risk factors, a nonlinear association was observed between SECON and FT insertion. Using cubic splines in the multivariate logistics regression model, the risk of FT insertion in hospitals where the SECON score dropped from 82 to 23 had an adjusted risk ratio (ARR) of FT insertion of 1.48 (95% confidence interval [CI] = 1.34-1.63); hospitals in which SECON dropped from 51 to 23 had an ARR of FT insertion of 1.38 (95% CI = 1.27-1.50).

CONCLUSION

Hospitalized dementia patients in hospitals in which continuity of care was lower had higher rates of FT insertions. Newer models of care are needed to enhance care continuity and thus ensure treatment consistent with likely outcomes of care and goals of care. J Am Geriatr Soc 68:1852-1856, 2020.

Site of Death, Place of Care, and Health Care Transitions Among US Medicare Beneficiaries, 2000-2015

IMPORTANCE

End-of-life care costs are high and decedents often experience poor quality of care. Numerous factors influence changes in site of death, health care transitions, and burdensome patterns of care.

OBJECTIVE

To describe changes in site of death and patterns of care among Medicare decedents.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study among a 20% random sample of 1 361 870 decedents who had Medicare fee-for-service (2000, 2005, 2009, 2011, and 2015) and a 100% sample of 871 845 decedents who had Medicare Advantage (2011 and 2015) and received care at an acute care hospital, at home or in the community, at a hospice inpatient care unit, or at a nursing home.

EXPOSURES

Secular changes between 2000 and 2015.

MAIN OUTCOMES AND MEASURES

Medicare administrative data were used to determine site of death, place of care, health care transitions, which are changes in location of care, and burdensome patterns of care. Burdensome patterns of care were based on health care transitions during the last 3 days of life and multiple hospitalizations for infections or dehydration during the last 120 days of life.

RESULTS

The site of death and patterns of care were studied among 1 361 870 decedents who had Medicare fee-for-service (mean [SD] age, 82.8 [8.4] years; 58.7% female) and 871 845 decedents who had Medicare Advantage (mean [SD] age, 82.1 [8.5] years; 54.0% female). Among Medicare fee-for-service decedents, the proportion of deaths that occurred in an acute care hospital decreased from 32.6% (95% CI, 32.4%-32.8%) in 2000 to 19.8% (95% CI, 19.6%-20.0%) in 2015, and deaths in a home or community setting that included assisted living facilities increased from 30.7% (95% CI, 30.6%-30.9%) in 2000 to 40.1% (95% CI, 39.9%-30.3% ) in 2015. Use of the intensive care unit during the last 30 days of life among Medicare fee-for-service decedents increased from 24.3% (95% CI, 24.1%-24.4%) in 2000 and then stabilized between 2009 and 2015 at 29.0% (95% CI, 28.8%-29.2%). Among Medicare fee-for-service decedents, health care transitions during the last 3 days of life increased from 10.3% (95% CI, 10.1%-10.4%) in 2000 to a high of 14.2% (95% CI, 14.0%-14.3%) in 2009 and then decreased to 10.8% (95% CI, 10.6%-10.9%) in 2015. The number of decedents enrolled in Medicare Advantage during the last 90 days of life increased from 358 600 in 2011 to 513 245 in 2015. Among decedents with Medicare Advantage, similar patterns in the rates for site of death, place of care, and health care transitions were observed.

CONCLUSIONS AND RELEVANCE

Among Medicare fee-for-service beneficiaries who died in 2015 compared with 2000, there was a lower likelihood of dying in an acute care hospital, an increase and then stabilization of intensive care unit use during the last month of life, and an increase and then decline in health care transitions during the last 3 days of life.

How integrated are services for patients with chronic obstructive pulmonary disease? Perceptions of patients and health care providers

Chronic obstructive pulmonary disease (COPD) is a common cause of hospital readmissions worldwide. Outcomes for COPD patients improve if care is more integrated. COPD patients and their health care providers at a district hospital and community health service were interviewed about their perceptions of integration of care. Patients were confused about provider roles, had little understanding of their disease, had difficulty accessing services and did not have COPD action plans. Health care providers espoused integration of COPD care. Care was reasonably well integrated in the hospital. Integration of care was compromised in the community because COPD patients went to the emergency department when symptoms became unmanageable, while only attending their GPs for routine booked appointments. Integration could be improved if health care providers spent more time with patients, promoting understanding of the disease, supporting self-management and liaising with other providers. Patients would benefit from an action plan and additional support. Potentially preventable COPD admissions will continue without action to improve integration of community services and patients’ understanding of their condition.

Reduction of nitrogenase Fe protein from Azotobacter vinelandii by dithionite: quantitative and qualitative effects of nucleotides, temperature, pH and reaction buffer

Oxidized Fe protein from Azotobacter vinelandii (Av2(0)) was reduced by dithionite (DT) in the absence and presence of nucleotides, over the temperature range 10-40 degrees C, over the pH range 7-8, and in various buffers--inorganic phosphate, TES, HEPES, and Tris. The reduction of each species of Fe protein--Av2(0), Av2(0)(MgATP)2, and Av2(0)(MgADP)2--was resolved into at least three exponential phases, with relative amplitudes of each phase varying over the range of experimental conditions, suggesting a dynamic population shift of kinetically distinct species. The rapid phase of Av2(0) reduction predominated at low temperature and pH, and in Tris buffer; rapid Av2(0)(MgATP)2 reduction was favored at high temperature and pH, and in phosphate buffer; and Av2(0)(MgADP)2 reduction was favored under more physiologically relevant conditions of 20 degrees C, pH 7.5, and in phosphate buffer. The rates of reduction of Fe protein species did not change with buffer, but temperature and pH do have an effect on the rates. With the appropriate constants, an empirically derived equation estimates the rate of Fe protein reduction at any temperature and pH within the limits 10-40 degrees C and pH 7-8, for a given species of Fe protein, and a given phase of the reaction. At 23.0 degrees C and pH 7.4, the rate of the dominant phase of Av2(0) reduction is 1.9 x 10(8) M(-1) s(-1). Under the same conditions, the rates of the two dominant phases of Av2(0)(MgATP)2 reduction are 1.2 x 10(6) and 1.5 x10 (5) M(-1) s(-1); and the rate of the dominant phase of Av2(0)(MgADP)2 reduction is 3.5 x 10(6) in M(-1) s(-1). Thermodynamic activation parameters for each phase of reduction were calculated. No breaks in the Arrhenius plots for any Fe protein species were observed.

Multiple risk factor evaluation in a hypertension clinic

Hypertension is associated with abnormal lipoprotein metabolism, which may be exacerbated by some groups of antihypertensive drugs and represents an additional powerful coronary heart disease risk factor. Of our Hypertension Clinic population, 75% had a total fasting serum cholesterol greater than 5.2 mmol/l. Dietary advice and adjustment of antihypertensive therapy has achieved significant reductions in total cholesterol, serum triglycerides and body weight (14%, 18% and 4.3%, respectively) in a cohort of 65 patients reassessed over a period of 3-21 months. The reduction in cholesterol is likely to represent at least a 28% reduction in the risk of a major coronary heart disease event, even before taking account of any improvement in other coronary heart disease risk factors.