Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Using trained dogs and organic semi-conducting sensors to identify asymptomatic and mild SARS-CoV-2 infections: an observational study

BACKGROUND

A rapid, accurate, non-invasive diagnostic screen is needed to identify people with SARS-CoV-2 infection. We investigated whether organic semi-conducting (OSC) sensors and trained dogs could distinguish between people infected with asymptomatic or mild symptoms, and uninfected individuals, and the impact of screening at ports-of-entry.

METHODS

Odour samples were collected from adults, and SARS-CoV-2 infection status confirmed using RT-PCR. OSC sensors captured the volatile organic compound (VOC) profile of odour samples. Trained dogs were tested in a double-blind trial to determine their ability to detect differences in VOCs between infected and uninfected individuals, with sensitivity and specificity as the primary outcome. Mathematical modelling was used to investigate the impact of bio-detection dogs for screening.

RESULTS

About, 3921 adults were enrolled in the study and odour samples collected from 1097 SARS-CoV-2 infected and 2031 uninfected individuals. OSC sensors were able to distinguish between SARS-CoV-2 infected individuals and uninfected, with sensitivity from 98% (95% CI 95-100) to 100% and specificity from 99% (95% CI 97-100) to 100%. Six dogs were able to distinguish between samples with sensitivity ranging from 82% (95% CI 76-87) to 94% (95% CI 89-98) and specificity ranging from 76% (95% CI 70-82) to 92% (95% CI 88-96). Mathematical modelling suggests that dog screening plus a confirmatory PCR test could detect up to 89% of SARS-CoV-2 infections, averting up to 2.2 times as much transmission compared to isolation of symptomatic individuals only.

CONCLUSIONS

People infected with SARS-CoV-2, with asymptomatic or mild symptoms, have a distinct odour that can be identified by sensors and trained dogs with a high degree of accuracy. Odour-based diagnostics using sensors and/or dogs may prove a rapid and effective tool for screening large numbers of people.Trial Registration NCT04509713 (clinicaltrials.gov).

Detection of SARS-CoV-2 by Canine Olfaction: A Pilot Study

Background

As the number of coronavirus disease 2019 (COVID-19) cases continue to surge worldwide and new variants emerge, additional accurate, rapid, and noninvasive screening methods to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are needed. The number of COVID-19 cases reported globally is >455 million, and deaths have surpassed 6 million. Current diagnostic methods are expensive, invasive, and produce delayed results. While COVID-19 vaccinations are proven to help slow the spread of infection and prevent serious illness, they are not equitably available worldwide. Almost 40% of the world’s population remains unvaccinated. Evidence suggests that SARS-CoV-2 virus–associated volatile organic compounds found in the breath, urine, and sweat of infected individuals can be detected by canine olfaction. Medical detection dogs may be a feasible, accurate, and affordable SARS-CoV-2 screening method.

Methods

In this double-blinded, case–control, validation study, we obtained sweat samples from inpatients and outpatients tested for SARS-CoV-2 by a polymerase chain reaction test. Medical detection dogs were trained to distinguish SARS-CoV-2-positive samples from SARS-CoV-2-negative samples using reward-based reinforcement.

Results

Samples were obtained from 584 individuals (6–97 years of age; 24% positive SARS-CoV-2 samples and 76% negative SARS-CoV-2 samples). In the testing phase, all dogs performed with high accuracy in detecting SARS-CoV-2. The overall diagnostic sensitivity was 98%, and specificity was 92%. In a follow-up phase, 1 dog screened 153 patients for SARS-CoV-2 in a hospital setting with 96% diagnostic sensitivity and 100% specificity.

Conclusions

Canine olfaction is an accurate and feasible method for diagnosis of SARS-CoV-2, including asymptomatic and presymptomatic infected individuals.

Feasibility of integrating canine olfaction with chemical and microbial profiling of urine to detect lethal prostate cancer

Prostate cancer is the second leading cause of cancer death in men in the developed world. A more sensitive and specific detection strategy for lethal prostate cancer beyond serum prostate specific antigen (PSA) population screening is urgently needed. Diagnosis by canine olfaction, using dogs trained to detect cancer by smell, has been shown to be both specific and sensitive. While dogs themselves are impractical as scalable diagnostic sensors, machine olfaction for cancer detection is testable. However, studies bridging the divide between clinical diagnostic techniques, artificial intelligence, and molecular analysis remains difficult due to the significant divide between these disciplines. We tested the clinical feasibility of a cross-disciplinary, integrative approach to early prostate cancer biosensing in urine using trained canine olfaction, volatile organic compound (VOC) analysis by gas chromatography-mass spectroscopy (GC-MS) artificial neural network (ANN)-assisted examination, and microbial profiling in a double-blinded pilot study. Two dogs were trained to detect Gleason 9 prostate cancer in urine collected from biopsy-confirmed patients. Biopsy-negative controls were used to assess canine specificity as prostate cancer biodetectors. Urine samples were simultaneously analyzed for their VOC content in headspace via GC-MS and urinary microbiota content via 16S rDNA Illumina sequencing. In addition, the dogs' diagnoses were used to train an ANN to detect significant peaks in the GC-MS data. The canine olfaction system was 71% sensitive and between 70-76% specific at detecting Gleason 9 prostate cancer. We have also confirmed VOC differences by GC-MS and microbiota differences by 16S rDNA sequencing between cancer positive and biopsy-negative controls. Furthermore, the trained ANN identified regions of interest in the GC-MS data, informed by the canine diagnoses. Methodology and feasibility are established to inform larger-scale studies using canine olfaction, urinary VOCs, and urinary microbiota profiling to develop machine olfaction diagnostic tools. Scalable multi-disciplinary tools may then be compared to PSA screening for earlier, non-invasive, more specific and sensitive detection of clinically aggressive prostate cancers in urine samples.

Could bio-detection dogs be used to limit the spread of COVID-19 by travellers?

The COVID-19 epidemic has had an unprecedented impact on the tourism sector. Trained disease detection dogs could be used for non-invasive screening at border entry points to reduce the likelihood of re-introduction of SARS-CoV-2 and limit the need for the self-isolation of all passengers.

An Owner-Independent Investigation of Diabetes Alert Dog Performance

Objective: To quantify Diabetes Alert Dog (DAD) performance by using owner-independent measures.

Research Design and Methods: Eight owners of accredited DADs used a FreeStyle Libre Flash Glucose Monitoring System (FGMS). Concurrent Closed Circuit Television (CCTV) footage was collected for between 5 and 14 days in each owner's home or workplace. The footage was blind-coded for dogs' alerting behaviors. The sensitivity, False Positive Rate and Positive Predictive Values (PPV) of dogs' alerts to out-of-range (OOR) episodes were calculated. Ratings for 11 attributes describing participant's lifestyle and compliance (taken from each dog's instructor) and the percentage of DAD alerts responded to by the owner as per training protocol (taken from CCTV footage) were assessed for association with dog performance.

Results: Dogs alerted more often when their owners' glucose levels were outside vs. inside target range (hypoglycaemic 2.80-fold, p = 0.001; hyperglycaemic 2.29-fold, p = 0.005). Sensitivity to hypoglycaemic episodes ranged from 33.3 to 91.7%, the mean was 55.9%. Mean PPV for OOR episodes was 69.7%. Sensitivity and PPV were associated with aspects of the dog and owner's behavior, and the owner's adherence to training protocol.

Conclusions: Owner-independent methods support that some dogs alert to hypo- and hyperglycaemic events accurately, but performance varies between dogs. We find that DAD performance is affected by traits and behaviors of both the dog and owner. Combined with existing research showing the perceived psychosocial value and reduced critical health care needs of DAD users, this study supports the value of a DAD as part of a diabetes care plan. It also highlights the importance of ongoing training and continued monitoring to ensure optimal performance.

Application of quality improvement techniques to reduce parenteral nutrition wastage in a national intestinal failure unit

Objectives

Parenteral nutrition (PN) costs approximately £80 per day per bag. Unpredictable changes in patients' clinical condition, venous access loss or reasons related to the processes involved in administering PN can lead to PN wastage. Cost efficiencies are imperative to optimise limited resource utilisation in all current healthcare economies. We undertook a quality improvement (QI) project to reduce PN wastage in an adult acute hospital setting. The project SMART's (specific, measurable, achievable, realistic, time-based) objective was reducing in-patient PN wastage by 10% in 9 months using QI methodology on a national intestinal failure unit (IFU).

Method

Wastage reasons were evaluated through pareto charts to target waste reduction using 'Plan, Do, Study, Act' (PDSA) cycles. Variation was mapped using c-charts.

Results

12-week baseline wastage data predicted 1000 bags wasted per annum (p.a.). PDSA cycles actioned included: regular enhanced clinical team awareness of wastage; unused PN bags redistributed within expiry date; stock bag rotation; critical path analysis of PN bag journey; enhanced discharge planning/coordination; reorganisation of fridge PN storage according to weekday; changing ordering frequency and bag type (from tailored to standard) to increase flexibility around discharge date and PN weaning. Implementation of PDSA cycles led to a 34% reduction in PN wastage in 9 months.

Conclusion

In a high-use IFU, PN wastage is common and costly. Using a QI approach with concurrent PDSA cycles and a motivated multidisciplinary team, high levels of wastage reduction are possible with associated significant cost savings and from this study a predicted cost saving of approximately £30 000 p.a.

Using sniffing behavior to differentiate true negative from false negative responses in trained scent-detection dogs

False negatives are recorded in every chemical detection system, but when animals are used as a scent detector, some false negatives can arise as a result of a failure in the link between detection and the trained alert response, or a failure of the handler to identify the positive alert. A false negative response can be critical in certain scenarios, such as searching for a live person or detecting explosives. In this study, we investigated whether the nature of sniffing behavior in trained detection dogs during a controlled scent-detection task differs in response to true positives, true negatives, false positives, and false negatives. A total of 200 videos of 10 working detection dogs were pseudorandomly selected and analyzed frame by frame to quantify sniffing duration and the number of sniffing episodes recorded in a Go/No-Go single scent-detection task using an eight-choice test apparatus. We found that the sniffing duration of true negatives is significantly shorter than false negatives, true positives, and false positives. Furthermore, dogs only ever performed one sniffing episode towards true negatives, but two sniffing episodes commonly occurred in the other situations. These results demonstrate how the nature of sniffing can be used to more effectively assess odor detection by dogs used as biological detection devices.

Investigation into the value of trained glycaemia alert dogs to clients with type I diabetes

Previous studies have suggested that some pet dogs respond to their owners' hypoglycaemic state. Here, we show that trained glycaemia alert dogs placed with clients living with diabetes afford significant improvements to owner well-being. We investigated whether trained dogs reliably respond to their owners' hypoglycaemic state, and whether owners experience facilitated tightened glycaemic control, and wider psychosocial benefits. Since obtaining their dog, all seventeen clients studied reported positive effects including reduced paramedic call outs, decreased unconscious episodes and improved independence. Owner-recorded data showed that dogs alerted their owners, with significant, though variable, accuracy at times of low and high blood sugar. Eight out of the ten dogs (for which owners provided adequate records) responded consistently more often when their owner's blood sugars were reported to be outside, than within, target range. Comparison of nine clients' routine records showed significant overall change after obtaining their dogs, with seven clients recording a significantly higher proportion of routine tests within target range after obtaining a dog. HbA1C showed a small, non significant reduction after dog allocation. Based on owner-reported data we have shown, for the first time, that trained detection dogs perform above chance level. This study points to the potential value of alert dogs, for increasing glycaemic control, client independence and consequent quality of life and even reducing the costs of long-term health care.

Perioperative headache and day case surgery

BACKGROUND AND OBJECTIVE

Headache is a common and distressing morbidity associated with day case surgery. We undertook a prospective, observational study to identify risk factors associated with perioperative headache in a modern, day case surgery setting.

METHODS

Two hundred-and-thirty consecutive patients presenting for day case surgery were invited to complete a questionnaire about their previous experience of headache and various associated risk factors. Questionnaires were completed by 90% of patients. The presence of headache in the pre- or postoperative period was also documented. We used multivariate logistic regression to model perioperative headache.

RESULTS

Increased frequency of previous headache, odds ratio (95% confidence interval) 1.9 (1.2-2.8) (P = 0.004) and low alcohol consumption 0.90 (0.87-0.98) (P = 0.019) were significant predictors. A history of migraine showed a trend towards being predictive 1.9 (0.9-4.0) (P = 0.055). Some risk factors thought to be important such as caffeine withdrawal and duration of starvation and fluid deprivation were not associated with perioperative headache in this setting.

CONCLUSIONS

In this study of risk factors associated with perioperative headache in day case surgery, increased frequency of headache and low alcohol consumption were independent risk factors.

A comparison of the prevalence of respiratory illness and non-specific health symptoms in two Victorian cities

OBJECTIVE

To compare the prevalence of respiratory illness and non-specific health symptoms among adults and children aged 4-15 years living in Portland and Warrnambool, Victoria.

METHODS

A postal survey of 3,903 adults in Portland and Warrnambool systematically selected from the electoral roll was undertaken. Both an adults and children's questionnaire were enclosed in the mailing to each adult. If there were children aged 4-15 years in the household, an adult was asked to complete a questionnaire for the child who would next celebrate a birthday. Questionnaires were returned by 2,111 adults (54%) and for 585 children.

RESULTS

No significant differences in the prevalence of self-reported asthma or wheeze were observed among adults or children residing in Portland and Warrnambool. The likelihood of itchy eyes, skin rash and stuffy nose was significantly higher in Portland adults and children compared with those in Warrnambool. Dry cough at night was increased among Portland children, but not significantly so.

CONCLUSIONS

Higher rates of non-specific symptoms were observed in Portland but from a cross-sectional survey such as this, it is not possible to identify the cause of these higher rates. They may be related to environmental factors such as pollens or emissions from aluminium production, fertiliser production or bulk handling activities on the wharf, or they may be attributable to other factors such as response or recall bias.

Comparison of the effects of intravenous alfentanil and esmolol on the cardiovascular response to double-lumen endobronchial intubation

We compared the effect of alfentanil 10 microg.kg-1 and esmolol 1.5 mg.kg-1 on the cardiovascular responses to laryngoscopy and double-lumen endobronchial intubation in two groups of 20 ASA 2-3 patients undergoing pulmonary surgery, in a randomised double-blind study. Arterial pressure and heart rate decreased after induction of anaesthesia and increased after intubation in both groups (p < 0.05) but remained at or below baseline values, and changes were comparable in both groups. Plasma catecholamine concentrations decreased after induction of anaesthesia in both groups (p < 0.05). Epinephrine concentrations increased in the esmolol group after intubation (p < 0.05) but remained below baseline in the alfentanil group (p < 0.05). Norepinephrine concentrations increased significantly in both groups after intubation but were higher in the esmolol group (p < 0.05). Although both esmolol 1.5 mg.kg-1 and alfentanil 10 microg.kg-1 similarly attenuated the arterial pressure and heart rate response to endobronchial intubation, plasma catecholamine concentrations increased in the esmolol group to values greater than previously reported after tracheal intubation.

Routine antenatal Rhesus D immunoglobulin prophylaxis: the results of a prospective 10 year study

OBJECTIVE

To assess the clinical and financial impact, and identify the problems, of providing routine antenatal RhD immunoglobulin prophylaxis for Rhesus D negative nulliparae.

DESIGN

A retrospective (1980-1986) and prospective (1987-1996) comparison between two similar populations, one population with nulliparae offered routine RhD immunoglobulin 500 IU prophylaxis at 28 and 34 weeks of gestation part way through the study period, and the other population not offered prophylaxis at any time.

SETTING

Obstetric units in two counties (three health districts) with similar annual numbers of maternities and the Regional Blood Transfusion Service antenatal serology laboratory.

PARTICIPANTS

Non-sensitised Rhesus D negative pregnant nulliparae.

INTERVENTIONS

Intramuscular RhD immunoglobulin 500 IU at 28 and 34 weeks of gestation to eligible women booked for confinement in one county; the intervention not offered in the other county.

MAIN OUTCOME MEASURES

1. Rhesus D sensitised second pregnancy rate; 2. success in providing prophylaxis to eligible women; 3. serology laboratory activity changes; 4. potential savings from the prophylaxis programme.

RESULTS

Prophylaxis significantly reduced iso-immunisation in the next pregnancy when compared with historical (OR 0.28, CI 0.14-0.53; P < 0.0001) and contemporary controls (OR 0.43, CI 0.22-0.86; P = 0.02). However, success at achieving comprehensive prophylaxis was disappointing, with only 89% of eligible women receiving the first injection, 74% both injections, and for only 29% were both at the correct gestation. Fifty-two percent of women delivered after 40 weeks of gestation, beyond the period of adequate prophylaxis protection. The savings in antenatal interventions, neonatal care and possible long term ill-health that result from very preterm birth should be considerable.

CONCLUSION

Routine prophylaxis for nulliparae significantly reduces the incidence of sensitised next pregnancies with consequent savings, and its adoption nationwide should be encouraged. A programme offering antenatal prophylaxis for all Rhesus D negative women is unlikely to be economic. Improvement in uptake of prophylaxis is needed; alternative administration strategies should be explored.

Extreme exposure: the Sydney to Hobart yacht race and the role of prediction

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Epidemiology and detection of cervical cancer. Implementing the national screening policy

The epidemiological bases of primary prevention and early detection of cancer of the uterine cervix are presented with emphasis on recent developments that are important for clinical practice. The progress of the implementation of the Australian cervical cancer screening policy is also discussed. A Medline search on cervical cancer, 1991-1996, was supplemented by material from international and local authorities, including reports on all aspects of cervical screening in Australia. National and international patterns of risk factors, predictors of progression and regression of precancerous lesions, cervical cancer incidence and mortality are summarised, with emphasis on the most recent and local research. Human papilloma virus (HPV) types are important causes of cervical intra-epithelial neoplasia (CIN) and squamous cell carcinoma. Most cervical screening is performed during medical consultations; additional financial incentives to promote correct targeting of this screening test should be explored. The Commonwealth Government is developing a national policy for the training of persons to provide cervical screening to supplement that provided by medical practitioners. The improvements in the national application of cervical screening should continue with the development of quality assurance at all stages of the screening pathway.

Coronary artery disease following repair of tetralogy of Fallot: implications and management

A 62-year-old man underwent successful coronary artery bypass for unstable angina 34 years after a complete repair of tetralogy of Fallot. Coronary risk factors were hypertension and a positive family history. While coronary disease was the presenting complaint, he had evidence of widespread atherosclerosis. He is the first patient reported to undergo coronary artery bypass following repair of tetralogy of Fallot. Coronary artery disease complicating tetralogy of Fallot has been mentioned five times in the literature. As the population of patients who have undergone tetralogy of Fallot ages, the number showing signs of coronary disease will likely rise. Thus, vigilance regarding risk factor modification must encompass these patients as they age.

High prevalence of Helicobacter pylori antibodies in an institutionalized population: evidence for person-to-person transmission

OBJECTIVE

To evaluate the prevalence of H. pylori antibodies in mentally and physically handicapped adults living together in a long-term care facility.

METHODS

One hundred twenty-two institutionalized subjects from six living areas were compared to a normal representative Caucasian population obtained by random sampling from the urban population area of Melbourne. Serum samples from 1977 and 1989 from 122 subjects were tested for H. pylori antibody by an ELISA technique. The data were analyzed by Student's t test, chi 2 test and logistic regression.

RESULTS

Ninety-two of the 122 subjects (75%) from whom sera was collected in 1989 were seropositive for H. pylori, compared with only 23% in age- and sex-matched control subjects (p < 0.0001). The prevalence of H. pylori antibodies in 1977 was 34% (42/122). Of the remaining 80 seronegative subjects, 51 (61.4%) converted to became positive in the 12-yr interval. The annual seroconversion rate was 7.4%, with an average of 4.25 newly positive subjects each year. The prevalence of H. pylori in 1989 was significantly higher than in 1977 after adjustment for age (odds ratio 2.39, 95% CI 1.1-5.3, p = 0.03).

CONCLUSIONS

H. pylori antibodies are significantly more prevalent in institutionalized adults compared with controls from the general population. These data support the hypothesis that H. pylori is acquired by either fecal-oral or oral-oral transmission.

Tropospheric ozone: respiratory effects and Australian air quality goals

OBJECTIVE

To review the health effects of tropospheric ozone and discuss the implications for public health policy.

DESIGN

Literature review and consultation with scientists in Australia and overseas. Papers in English or with English language abstracts were identified by Medline search from the international peer reviewed published reports. Those from the period 1980-93 were read systematically but selected earlier papers were also considered. Reports on ozone exposures were obtained from environmental agencies in the region.

RESULTS

Exposure to ozone at concentrations below the current Australian air quality goal (0.12 ppm averaged over one hour) may cause impaired respiratory function. Inflammatory changes in the small airways and respiratory symptoms result from moderate to heavy exercise in the presence of ozone at levels of 0.08-0.12 ppm. The changes in respiratory function due to ozone are short lived, vary with the duration of exposure, may be modified by levels of other pollutants (such as sulphur dioxide and particulates), and differ appreciably between individuals. Bronchial lavage studies indicate that inflammation and other pathological changes may occur in the airways before reductions in air flow are detectable, and persist after respiratory function has returned to normal. It is not known whether exposures to ozone at low levels (0.08-0.12 ppm) cause lasting damage to the lung or, if such damage does occur, whether it is functionally significant. At present, it is not possible to identify confidently population subgroups with heightened susceptibility to ozone. People with asthma may be more susceptible to the effects of ozone than the general population but the evidence is not consistent. Recent reports suggest that ozone increases airway reactivity on subsequent challenge with allergens and other irritants. Animal studies are consistent with the findings in human populations.

CONCLUSION

A new one hour air quality ozone goal of 0.08 ppm for Australia, and the introduction of a four hour goal of 0.06 ppm are recommended on health grounds.

Stigmatisation of people with learning disabilities in general hospitals

Stigmatisation of people with learning disabilities is a barrier to good nursing care. In general, hospital nurses are likely to possess negative attitudes to those with learning disabilities. Structures and direct contact can minimise stigmatisation.

Case report: anti-Cra in pregnancy

A 39-year-old Grenadian multiparous patient presented in the 12th week of pregnancy. Her red cells were found to have the rare Cr(a-) (ISBT Number 202001) phenotype within the Cromer complex, and her serum contained anti-Cra. To date, anti-Cra has not been implicated in hemolytic disease of the newborn (HDN), but there are very few published reports on this topic. This case provided an excellent opportunity for study. The patient's serum showed no detectable functional activity in in vitro antibody-dependent, cell-mediated cytotoxicity assays, and no increase in the strength of the antibody during the pregnancy. The newborn infant showed no clinical signs of HDN, and was of normal weight. This case study suggests that anti- Cra is not implicated in HDN.

Paraspinal soft-tissue sarcoma. Classification of 14 cases

Fourteen patients were treated surgically for soft-tissue sarcoma arising in the paraspinal muscles. Eleven patients received adjuvant irradiation administered before or after resection. In describing the treatment and outcomes of these patients, a new classification of paraspinal soft-tissue sarcoma is introduced that is based on the anatomic relationship of the tumor to the spinal lamina and the epidural space. This classification can be used in planning combined modality treatment for paravertebral sarcomas. Lesions that extend through the lamina into the epidural space present an unanswered problem for local control.

A comparison of the impact of institutionalization on spouse and nonspouse caregivers

We report on a study of 106 spouse and nonspouse primary caregivers of cognitively impaired older people. Half of these caregivers cared for someone in a community setting, half cared for someone in an institution (a nursing home or hospital). The study used the multidimensional Caregiver Burden Inventory (CBI) to measure the burden that these caregivers felt. A 2 x 2 multivariate analysis of variance found an effect of the interaction of relationship and living arrangement on two CBI subscales: Time Dependence Burden and Developmental Burden. Spouses showed a significantly greater difference in Time Dependence Burden scores than did nonspouses in both living arrangement groups, and nonspouses showed a significantly greater difference in Developmental Burden than did spouses in both groups. We conclude with a discussion of how programs can help different types of caregivers cope with feelings of burden.

Cancer of the uterine cervix and screening of Aboriginal women

Carcinoma of the cervix has not been widely reported as an important health problem for Aboriginal women. From four sources, we have studied cervical cancer death rates, abnormalities detected by cervical cytology screening, and the proportion of women who had been screened. First, from the Northern Territory for the years 1979-1983, we present a relative risk of 6.3 (95% confidence interval, 3.0-11.6) for cervical cancer deaths in Aboriginal women compared with all Australian women. Second, the screening and disease rates in Aboriginal women were profiled within a large laboratory in Victoria. Since 1984, a fourfold increase in the number of smears taken at Aboriginal health services is apparent. In women attending these services, a high rate of significantly abnormal smears is evident. Third, to study the extent of screening, we interviewed Aboriginal women in a Victorian country setting and fourth, we examined a random sample of medical records from an Aboriginal Health Service. The proportion screened at least once rose from 5/47 (11%) among women whose most recent consultation with the Health Service was during the years 1974-1980 to 51/170 (31%) women who attended from 1981-1987 (p less than 0.01). Aboriginal communities may interpret these trends favourably as they encourage their women to be screened regularly to reduce cervical cancer mortality.

Application of a multidimensional caregiver burden inventory

Multidimensional measures of caregiver burden give a sensitive reading of caregivers' feelings and a sophisticated picture of caregivers' responses to the demands of care. This paper reports on the development of a 24-item, five-subscale Caregiver Burden Inventory (CBI) and demonstrates its use as a diagnostic tool for professional caregivers. It concludes with a discussion of several ways that professional caregivers can use this multidimensional measure of caregiver burden.

Caregiver response to Alzheimer's disease

Research on Alzheimer's Disease caregivers has tried to find a link between 1) the length of time a caregiver has been giving care; or 2) the physical condition of the patient and the experiences and needs of the caregiver. This study found no significant correlation between length of time a caregiver had given care to a particular patient and the caregiver's subjective feelings of caregiver burden. It found a significant, moderate correlation between caregiver burden and the patient's functional ability. It found that caregivers' subjective feelings and needs best predict their feelings of burden. This report concludes with suggestions on how to improve support for caregivers in light of these findings.

Foodborne Snow Mountain agent gastroenteritis in a school cafeteria

In 1984, an outbreak of gastroenteritis occurred at a school with 1,860 students in Brooklyn, NY. In a single-stage cluster sample of 375 students, 129 (34%) had illnesses that met our case definition of vomiting or diarrhea. The mean incubation period was 26 hours, and the mean illness duration was 24 hours. All case students had eaten in the cafeteria on at least one day between Nov 13 and 16, compared with 174/214 (81%) noncase students (P = 10(-8), Fisher exact test). Foods implicated were french fries (relative risk 1.7, 95% confidence limits 1.4, 2.0) and hamburgers (relative risk 1.6, 95%, confidence limits 1.2, 2.1). Two cafeteria employees had served those foods while affected by diarrhea. By a recently developed blocking enzyme-linked immunosorbent assay, six of 11 (55%) case students showed fourfold antibody increases between acute- and convalescent-phase serum samples for Snow Mountain agent, a Norwalk-like virus, compared with one of ten (10%) noncase students (P = .04, Fisher exact test). We strongly suspect, but cannot document conclusively, that the Snow Mountain agent was spread to students on a vector of hot foods contaminated by ill food handlers. Implicated foods conferred low relative risks and could only have accounted for 74% of cases of illness. The strong association between cafeteria exposure and illness, therefore, suggests that additional modes of spread occurred.

Labetalol compared with prindolol plus hydraliazine in the treatment of hypertension: a double-blind cross-over study

The hypotensive action of labetalol, a new drug with alpha-adrenoceptor and beta-adrenoceptor blocking action, was compared with that of a combination of prindolol and hydrallazine. Fourteen patients with mild to moderately severe hypertension completed a double-blind cross-over study with treatment periods of eight weeks. Both treatments were effective and, in the doses which were used, produced clinically significant lowering of blood pressure (reduction of mean blood pressure by more than 10 mm Hg) both in clinic and in home blood pressures in 12 of the 14 patients. The action of labetalol (600 mg twice a day) was approximately equivalent to that of prindolol (15 mg twice a day) plus hydrallazine (50 mg three times a day). There was a tendency for the second treatment (irrespective of nature) to be more effective than the first. However, when the results for each treatment were combined, the fall in the blood pressure due to labetalol was practically identical with that due to prindolol and hydrallazine. There were no toxic effects from either treatment and side effects were mild. Labetalol is a useful hypotensive drug with effect similar to that of a combination of a beta-adrenoceptor blocking drug and a vasodilator.