Population-based cohort study of variation in the use of emergency cholecystectomy for benign gallbladder diseases

Background

The aims of this prospective population-based cohort study were to identify the patient and hospital characteristics associated with emergency cholecystectomy, and the influences of these in determining variations between hospitals.

Methods

Data were collected for consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing the performance of emergency cholecystectomy were analysed by means of multilevel, multivariable logistic regression modelling using a two-level hierarchical structure with patients (level 1) nested within hospitals (level 2).

Results

Data were collected on 4744 cholecystectomies from 165 hospitals. Increasing age, lower ASA fitness grade, biliary colic, the need for further imaging (magnetic retrograde cholangiopancreatography), endoscopic interventions (endoscopic retrograde cholangiopancreatography) and admission to a non-biliary centre significantly reduced the likelihood of an emergency cholecystectomy being performed. The multilevel model was used to calculate the probability of receiving an emergency cholecystectomy for a woman aged 40 years or over with an ASA grade of I or II and a BMI of at least 25·0 kg/m2, who presented with acute cholecystitis with an ultrasound scan showing a thick-walled gallbladder and a normal common bile duct. The mean predicted probability of receiving an emergency cholecystectomy was 0·52 (95 per cent c.i. 0·45 to 0·57). The predicted probabilities ranged from 0·02 to 0·95 across the 165 hospitals, demonstrating significant variation between hospitals.

Conclusion

Patients with similar characteristics presenting to different hospitals with acute gallbladder pathology do not receive comparable care.

Understanding of informed consent by demented individuals

BACKGROUND

The informed consent process is central to the conduct of research but may be difficult for cognitively impaired participants to understand. The authors developed a brief test addressing the elements of informed consent for a specific minimum-risk nontreatment research protocol.

OBJECTIVE

To evaluate and document understanding of informed consent by elderly research participants across a range of dementia severity.

METHODS

The elements of informed consent regarding participation in a longitudinal study of healthy aging and dementia were reviewed with both demented (n = 250) and nondemented (n = 165) participants who then completed a short test requiring yes-no responses to assess understanding of these elements. Demented participants had very mild, mild, or moderate dementia as staged by the Clinical Dementia Rating.

RESULTS

After adjusting for education, performance on the test varied with dementia severity in mean differences and by correlation. All nondemented and very mildly demented participants and 92% of mildly demented participants provided correct answers for at least 8 of 10 true-false items, whereas only 67% of the moderately demented participants achieved this level of accuracy.

CONCLUSIONS

Demented individuals, very mild and mild, understood informed consent information for this nontreatment research study. Understanding notably declined in the moderate stage of dementia. Brief tests may be useful as one method to assess understanding of the consent process for specific studies.

Diagnosis of bovine brucellosis using a homogeneous fluorescence polarization assay

To evaluate the fluorescence polarization assay (FPA) for the serological diagnosis of bovine brucellosis, 118 sera from cattle which were culture positive for Brucella abortus, 1751 sera from cattle from premises containing cattle infected with B. abortus, 1222 sera from cattle vaccinated with B. abortus strain 19 and 1199 sera from cattle with no evidence of brucellosis were tested in Argentina, Chile, Mexico and in the American states of Iowa, Missouri and Texas. Initial determination of serological positivity and negativity was based upon reactivity in currently used serological tests, consisting of a rapid screening test, the rose-bengal or the buffered plate antigen tests, followed by a second serological test, the complement fixation test. Sensitivity of the FPA (sera from culture positive animals) ranged from 87.5% to 100%. Serological positivity of cattle from infected premises ranged from 65.5% to 99.0% while the % negative cattle in herds without evidence of brucellosis was between 94.9 and 100%. Of B. abortus strain 19 vaccinated cattle which were positive in at least one in-use serological tests, 88.2% were negative in the FPA. In contrast, previous Canadian studies, sensitivity values were 99.0% and 100% and the specificity in both cases was 100%. This discrepancy was probably due to the use of less well characterized sera in the current study.

Clinicopathologic studies in cognitively healthy aging and Alzheimer's disease: relation of histologic markers to dementia severity, age, sex, and apolipoprotein E genotype

OBJECTIVE

To study differences between subjects with Alzheimer disease (AD) and cognitively intact control subjects, with respect to brain histologic markers of AD, and the relationship of those markers in the AD group to severity of dementia, age at death, sex, and apolipoprotein E genotype.

SETTING

Washington University Alzheimer's Disease Research Center, St Louis, Mo.

DESIGN AND SUBJECTS

Consecutive neuropathologic series of 224 prospectively studied volunteer research subjects, 186 with dementia of the Alzheimer type (DAT) or "incipient" DAT and confirmed to have AD by postmortem examination and 13 cognitively intact subjects, confirmed to lack postmortem findings of AD.

MAIN OUTCOME MEASURES

Brain densities (number per square millimeter) of senile plaques and neurofibrillary tangles, extent of cerebral amyloid angiopathy, cortical Lewy bodies, and apolipoprotein E genotype.

RESULTS

Neocortical neurofibrillary tangle densities were substantially correlated with dementia severity, and to a greater degree than was true for senile plaque densities. When infarcts, hemorrhages, and Parkinson disease changes coexisted with AD, neurofibrillary tangle and senile plaque densities were lower. Plaque-predominant AD was found in a greater proportion of subjects with milder than more severe dementia. Entorhinal cortical Lewy bodies were no more frequent in plaque-predominant AD than in the remaining AD cases. Increasing age at death was negatively correlated with dementia severity and densities of senile plaques and neurofibrillary tangles. The apolipoprotein E epsilon4 allele frequency was greater in AD than in control subjects but decreased with increasing age. After controlling for dementia severity, senile plaque densities were only weakly related to epsilon4 allele frequency, and only in hippocampus. However, the degree of cerebral amyloid angiopathy was clearly related to epsilon4 allele frequency. Among subjects diagnosed during life as having DAT or incipient DAT, only 7% were found to have a neuropathologic disorder other than AD causing their dementia.

CONCLUSIONS

(1) The order of the strength of relationships between densities of histologic markers and dementia severity in AD is neurofibrillary tangles greater than cored senile plaques greater than total senile plaques. (2) Advanced age at death is associated with somewhat less severe dementia and fewer senile plaques and neurofibrillary tangles. (3) Plaque-predominant AD may represent a developmental stage in AD. (4) Despite a substantial effect of apolipoprotein E epsilon4 as a risk factor for AD, on decreasing the age at AD onset, and increasing the amount of cerebral amyloid angiopathy, its effect on senile plaque densities is variable and complex, being confounded with age, dementia severity, and methodologic differences. (5) Stringent clinical diagnostic criteria for DAT, even in the very mild stage, and senile plaque-based neuropathologic criteria for AD are highly accurate.

Clinical dementia rating training and reliability in multicenter studies: the Alzheimer's Disease Cooperative Study experience

Global ratings of dementia severity are used increasingly in clinical trials of antidementia compounds. Such ratings are clinically relevant, but their reliability in multicenter settings has not been determined. To evaluate the reliability of one global scale, the Clinical Dementia Rating (CDR), 82 investigators of the multicenter Alzheimer's Disease Cooperative Study participated in a training and reliability protocol using videotaped assessments of subjects in various stages of Alzheimer's disease. Following training, overall agreement of the investigators with "gold standard" CDR scores was 83%. These results indicate that the training protocol is useful for establishing good levels of agreement in staging dementia severity and that the CDR can be standardized as a clinical global scale for multicenter studies of Alzheimer's disease.

Cross-national interrater reliability of dementia diagnosis in the elderly and factors associated with disagreement

Thirteen researchers from five centers in Australia, Germany, the Netherlands, United Kingdom, and United States applied DSM-III-R and Clinical Dementia Rating (CDR) syndrome-level dementia criteria to written vignettes of 100 elderly people identified in clinics or community surveys. Subjects ranged in type from cognitively intact to severely demented and many were also frail, partially sighted, or deaf. This paper concerns reliability within and between centers, and the relationship between reliability and factors such as diagnostic criteria, dementia severity, and respondents' clinical characteristics. Within-center interrater reliability was high, more so for "yes-no" DSM-III-R diagnoses than the multi-level CDR. Between-center rates were lower but still moderate to good. Concordance was lower for intermediate dementia levels than for no dementia and severe dementia. Physical disability made an additional contribution to uncertainty but deafness, poor vision, anxiety, and depression had no discernible effects. Reliability levels are likely to be lower in representative aged populations than in carefully selected clinical groups.

Longitudinal study of EEG and evoked potentials in neurologically asymptomatic HIV infected subjects

Serial electroencephalograms (EEGs) and multimodality evoked potentials (EPs) were performed along with neurological and neuropsychological evaluation, cerebrospinal fluid assessment and magnetic resonance imaging at 6 month intervals in 73 neurologically asymptomatic HIV infected subjects. The results were compared with 50 age- and sex-matched controls. EEG was abnormal in 2 subjects (3%) initially and was abnormal in 7 (9%) subjects by the last examination. EEG abnormality (diffuse slowing) correlated significantly with slowed reaction time in neuropsychological testing (P < 0.05). VEP and BAEP provided low yields of 1.3% and 4% respectively. SEP was abnormal in 7 (9%) of the subjects initially and in 10 (13%) subjects by the last testing, with 80% of the abnormalities seen on the posterior tibial study. In 3 subjects, initial SEP abnormalities predicted later development of myelopathy and peripheral neuropathy. Event-related auditory evoked potentials were performed in 39 subjects. They were abnormal in 5 subjects initially (12%) and in 6 subjects (15%) by the last examination and more commonly in advanced stages of the illness with lower T4 counts. This data shows the evolution and association of electrophysiological abnormalities in early HIV infection and suggests a predictive value for SEP in HIV infected asymptomatic individuals.

Prevalence and severity of morbidity among Gujarati Asian elders: a controlled comparison

Asian elders make relatively heavy use of health services: this may be due to higher levels of morbidity, but controlled comparisons have not been carried out. A comparison of the prevalence and severity of chronic diseases and use of health services of Asian and indigenous elders was made. A sample of 59 Gujarati Asians of mean age 62.9 years and 59 indigenous subjects of mean age 63.9 years of whom 42% (25 in each group) were female drawn from a general practice was studied. Asian subjects had a higher prevalence of diagnosed diseases, with the exception of chronic obstructive airways disease, but lower risk of falls and urinary incontinence. Asian subjects had higher life satisfaction scores and lower prevalence of depressed mood. Asian women were more likely to have had contact with primary care services. Both Asian men and women had more frequent hospital admissions, but similar levels of out-patient attendance. Body mass index, blood pressure and shoulder joint range of movement were similar for both Asians and the indigenous population. Asian subjects had significantly lower peak expiratory flow rates and hand grip strength. Asian elders have a higher risk of chronic diseases, but the impact of disease (indicated by life satisfaction, mood, and common disabilities) is less than among the indigenous population. Lower peak expiratory flow rates and grip strength among Asian elders are of concern since they may lead to premature arrival at age-related thresholds of physical capacity essential for independence in activities of daily living.

Reliability of clinical nurse specialists in the staging of dementia

We studied the reliability of master's-prepared clinical nurse specialists for the identification and staging of dementia, using videotapes of physician assessments of both healthy older persons and those with senile dementia of the Alzheimer type. The Washington University (St Louis, Mo) Clinical Dementia Rating system was the staging instrument. The results from three nurses, each reviewing 25 videotaped assessments, indicate that agreement is high between clinical nurse specialists and physicians for the presence and severity of dementia (kappa = .75). This study suggests that clinical nurse specialists can use the Clinical Dementia Rating scale effectively, and thus reliably identify and stage dementia.

Fatal disseminated cryptococcosis following intraocular involvement

A 33-year-old man was treated with systemic steroids for a retinal inflammatory lesion before the diagnosis of cryptococcal retinitis and meningitis was suspected. He died from central nervous system disease despite treatment with parenteral antifungals. Histopathological studies demonstrated ocular and disseminated systemic infection with Cryptococcus neoformans. Direct cryptococcal involvement of the eye is rare and is usually associated with disseminated disease. Systemic steroids must be used with caution, and patients who take these drugs require frequent monitoring.

Toxicity of intravitreal injection of fluconazole in the rabbit

Fluconazole is a new bis-triazole derivative proven highly effective against Candida in various animal models. To determine its potential use in exogenous fungal endophthalmitis, 13 New Zealand white rabbits were given intravitreal injections of up to 100 micrograms/0.1 mL of the antifungal. All eyes underwent biomicroscopy, ophthalmoscopy and electroretinography before and after the procedure. No evidence of toxic intraocular effects was detected with these techniques or on light microscopy, performed 8 days after injection. The results suggest that fluconazole has potential application in the treatment of exogenous fungal endophthalmitis.