Cardio-oncology: an overview on outpatient management and future developments

Recent advances in the early detection and treatment of cancer have led to increasing numbers of cancer survivors worldwide. Nonetheless, despite major improvements in the outcome of these patients, long-term side effects of radio- and chemotherapy affect both patient survival and quality of life, independent of the oncological prognosis. Chemotherapy-related cardiac dysfunction is one of the most notorious short-term side effects of anticancer treatment, occurring in ~10% of patients. Progression to overt heart failure carries a strikingly poor prognosis with a 2-year mortality rate of 60%. Early detection of left ventricular damage by periodic monitoring and prompt initiation of heart failure treatment is key in improving cardiovascular prognosis. To meet the growing demand for a specialised interdisciplinary approach for the prevention and management of cardiovascular complications induced by cancer treatment, a new discipline termed cardio-oncology has evolved. However, an uniform, multidisciplinary approach is currently lacking in the Netherlands. This overview provides an introduction and comprehensive summary of this emerging discipline and offers a practical strategy for the outpatient management of this specific patient population.     

Repeated epinephrine doses during prolonged cardiopulmonary resuscitation have limited effects on myocardial blood flow: a randomized porcine study

In cases where antidiabetic monotherapy is unable to sufficiently control glucose levels in patients with type-2 diabetes, treatment needs to be intensified. Determining factors that may be predictors for the occurrence of comorbidities in these patients is essential for improving the efficacy of clinical diabetes care. The DiaRegis prospective cohort study included 3,810 type-2 diabetics for whom the treating physician aimed to intensify and optimise antidiabetic treatment due to insufficient glucose control. Treatment intensification was defined as increasing the dose of the originally prescribed drug, and/or selecting an alternative drug, and/or prescribing an additional drug. The aims were to monitor the co-morbidity burden of type-2 diabetic patients over a follow-up of two years, and to identify multivariable adjusted predictors for the development of comorbidity and cardiovascular events. A total of 3,058 patients completed the 2 year follow-up. A substantial proportion of these patients had co-morbidities such as vascular disease, neuropathy, and heart failure at baseline. After treatment intensification, there was an increased use of DPP-4 inhibitors, insulin, and GLP-1 analogues, achieving reductions in HbA1c, fasting plasma glucose, and postprandial glucose. During the 2 year period 2.5% of patients (n = 75) died, 3.2% experienced non-fatal macrovascular events, 11.9% experienced microvascular events, and 4.3% suffered onset of heart failure. Predictors for combined macro-/microvascular complications/heart failure/death were found to be age (OR 1.36; 95% CI 1.10–1.68), prior vascular disease (1.73; 1.39–2.16), and history of heart failure (2.78; 2.10–3.68). Determining the factors that contribute to co-morbidities during intensive glucose-lowering treatment is essential for improving the efficacy of diabetes care. Our results indicate that age, prior vascular disease, and heart failure constitute important predictors of poor cardiovascular outcomes in patients receiving such therapy.     

Statin therapy in heart failure

PURPOSE OF REVIEW: The 3-hydroxy-3-methylglutaryl-coenzyme-A reductase inhibitors, or statins, have been shown to reduce cardiovascular morbidity and mortality among a wide spectrum of patients with established atherosclerotic vascular disease. Mounting experimental and clinical evidence also suggest a potential benefit as well as theoretical harm of statin therapy in patients with heart failure. RECENT FINDINGS: This article briefly summarizes the therapeutic properties of statins that may be of benefit to patients with heart failure and the theoretical adverse effects of cholesterol reduction in this group of patients. A number of nonrandomized clinical studies over the past several years have shown an association between statin use and reduced overall mortality. Several large-scale randomized studies designed to confirm these findings are currently under way. SUMMARY: Statin therapy appears to improve clinical outcomes in patients with both ischemic and nonischemic cardiomyopathy independently of their cholesterol-lowering properties. The theoretical adverse properties of statins in heart failure patients have not been substantiated in small to medium-sized clinical trials. Although the encouraging results of these preliminary studies suggest a role for statin therapy in heart failure, larger studies are needed to validate these findings. Several ongoing randomized trials are currently under way to evaluate the effect of statin therapy on cardiovascular outcomes in heart failure patients. The results of these studies, expected in the next several years, should provide scientific evidence for the role of statins in the treatment of failure.     

Association between Precipitation Upstream of a Drinking Water Utility and Nurse Advice Calls Relating to Acute Gastrointestinal Illnesses

Background

The River Göta Älv is a source of fresh-water for the City of Gothenburg (Sweden). We recently identified a clear association between upstream precipitation and indicator bacteria concentrations in the river water outside the intake to the drinking water utility. This study aimed to determine if variation in the incidence of acute gastrointestinal illnesses is associated with upstream precipitation.

Methods

We acquired data, covering 1494 days, on the daily number of telephone calls to the nurse advice line from citizens in Gothenburg living in areas with Göta Älv as a fresh-water supply. We separated calls relating to gastrointestinal illnesses from other medical concerns, and analyzed their association with precipitation using a distributed lag non-linear Poisson regression model, adjusting for seasonal patterns and covariates. We used a 0–21-day lag period for precipitation to account for drinking water delivery times and incubation periods of waterborne pathogens.

Results

The study period contained 25,659 nurse advice calls relating to gastrointestinal illnesses. Heavy rainfall was associated with increased calls the same day and around 5–6 days later. Consecutive days of wet weather were also found to be associated with an increase in the daily number of gastrointestinal concerns. No associations were identified between precipitation and nurse advice calls relating to other medical concerns.

Conclusion

An increase in nurse advice calls relating to gastrointestinal illnesses around 5–6 days after heavy rainfall is consistent with a hypothesis that the cause could be related to drinking water due to insufficient barriers in the drinking water production, suggesting the need for improved drinking water treatment.     

Nurse practitioners in accident and emergency departments: what do they do?

OBJECTIVE--To determine the distribution and scope of nurse practitioner schemes in accident and emergency departments in England and Wales; to describe the caseloads of doctors and nurse practitioners on two representative days; and to estimate the number of patients managed by nurse practitioners in the year to 31 March 1991. DESIGN--A postal survey of accident and emergency departments and a content analysis of case notes of new patients attending a representative sample of accident and emergency departments on two days. SETTING--All accident and emergency departments in England and Wales. PARTICIPANTS--Survey: 560 nurses in charge of accident and emergency departments. Census: case notes of 5814 patients in 37 accident and emergency departments. MAIN OUTCOME MEASURES--Survey: number of accident and emergency departments with nurse practitioner schemes. Census: demographic and clinical characteristics of new patients attending and whether nurse practitioner or doctor made diagnoses and ordered investigations, treatments, referrals, discharges. RESULTS--513 replies (92%) from 465 surveyed functioning accident and emergency departments and 48 departments recently closed. 27 (6%) departments used designated nurse practitioners and 159 (34%) "unofficial" nurse practitioners. Only 530 (9%) of the 5814 patients in the census were managed entirely or mainly by nurse practitioners, with higher proportions in ophthalmic departments (nearly 30%) and minor casualty departments (over 40%) than in major departments (3%). Most patients managed by nurse practitioners (86%) had minor trauma. In the year ending 31 March 1991 an estimated 390,000 (95% confidence interval 260,000 to 520,000) patients out of a total of 12.5 million (3.1%, 2.1% to 4.1%) were clinically managed by a nurse practitioner. CONCLUSIONS--Designated nurse practitioner schemes are rare. The volume and range of nurse practitioner work in major general accident and emergency departments is small compared with those in specialised and minor accident and emergency departments.     

The effect of a comprehensive lifestyle intervention on cardiovascular risk factors in pharmacologically treated patients with stable cardiovascular disease compared to usual care: a randomised controlled trial

ABSTRACT: BACKGROUND: The additional benefit of lifestyle interventions in patients receiving cardioprotective drug treatment to improve cardiovascular risk profile is not fully established.The objective was to evaluate the effectiveness of a target-driven multidisciplinary structured lifestyle intervention programme of 6 months duration aimed at maximum reduction of cardiovascular risk factors in patients with cardiovascular disease (CVD) compared with usual care. METHODS: A single centre, two arm, parallel group randomised controlled trial was performed. Patients with stable established CVD and at least one lifestyle-related risk factor were recruited from the vascular and cardiology outpatient departments of the university hospital. Blocked randomisation was used to allocate patients to the intervention (n = 71) or control group (n = 75) using an on-site computer system combined with allocations in computer-generated tables of random numbers kept in a locked computer file. The intervention group received the comprehensive lifestyle intervention offered in a specialised outpatient clinic in addition to usual care. The control group continued to receive usual care. Outcome measures were the lifestyle-related cardiovascular risk factors: smoking, physical activity, physical fitness, diet, blood pressure, plasma total/HDL/LDL cholesterol concentrations, BMI, waist circumference, and changes in medication. RESULTS: The intervention led to increased physical activity/fitness levels and an improved cardiovascular risk factor profile (reduced BMI and waist circumference). In this setting, cardiovascular risk management for blood pressure and lipid levels by prophylactic treatment for CVD in usual care was already close to optimal as reflected in baseline levels. There was no significant improvement in any other risk factor. CONCLUSIONS: Even in CVD patients receiving good clinical care and using cardioprotective drug treatment, a comprehensive lifestyle intervention had a beneficial effect on some cardiovascular risk factors. In the present era of cardiovascular therapy and with the increasing numbers of overweight and physically inactive patients, this study confirms the importance of risk factor control through lifestyle modification as a supplement to more intensified drug treatment in patients with CVD.Trial registrationISRCTN69776211 at http://www.controlled-trials.com.     

Modeling the relationship between LVAD support time and gene expression changes in the human heart by penalized partial least squares

MOTIVATION: Heart failure affects more than 20 million people in the world. Heart transplantation is the most effective therapy, but the number of eligible patients far outweighs the number of available donor hearts. The left mechanical ventricular assist device (LVAD) has been developed as a successful substitution therapy that aids the failing ventricle while a patient is waiting for the donor heart. We obtained genomics data from paired human heart samples harvested at the time of LVAD implant and explant. The heart failure patients in our study were supported by the LVAD for various periods of time. The goal of this study is to model the relationship between the time of LVAD support and gene expression changes. RESULTS: To serve the purpose, we propose a novel penalized partial least squares (PPLS) method to build a regression model. Compared with partial least squares and Breiman's random forest method, PPLS gives the best prediction results for the LVAD data.     

Inflammatory mediators and the failing heart: a translational approach

Recent studies have identified the importance of proinflammatory mediators in regulating cardiac structure in health and disease. Recent studies suggest that cytokines that are expressed within the myocardium in response to a environmental injury, namely tumor necrosis factor-alpha (TNF), interleukin-1 (IL-1) and the interleukin-6 (IL-6) family of cytokines play an important role in initiating and integrating homeostatic responses within the heart. However, these "stress-activated" cytokines all have the potential to produce cardiac decompensation when expressed at sufficiently high concentrations. Indeed, there is now a growing appreciation that these molecules may play an important role in mediating disease progression in the failing heart. The growing appreciation of the pathophysiological consequences of sustained expression of proinflammatory mediators in pre-clinical and clinical heart failure models culminated in a series of multicenter clinical trials that utilized "targeted" approaches to neutralize tumor necrosis factor (TNF) in patients with moderate to advanced heart failure. However, these targeted approaches have resulted in worsening heart failure, thereby raising a number of important questions about what role, if any, proinflammatory cytokines play in the pathogenesis of heart failure. This review will summarize the tremendous growth of knowledge that has taken place in this field, with a focus on what we have learned from the negative clinical trials, as well as the potential direction of future research in this area.     

Trends in the incidence and outcomes of heart failure in Ontario, Canada: 1997 to 2007

Background:

Heart failure is a leading cause of admission to hospital, but whether the incidence of heart failure is increasing or decreasing is uncertain. We examined temporal trends in the incidence and outcomes of heart failure in Ontario, Canada.

Methods:

Using population-based administrative databases of hospital discharge abstracts and physician health insurance claims, we identified 419 551 incident cases of heart failure in Ontario between Apr. 1, 1997, and Mar. 31, 2008. All patients were classified as either inpatients or outpatients based on the patient’s location at the time of the initial diagnosis. We tracked subsequent outcomes through linked administrative databases.

Results:

The age- and sex-standardized incidence of heart failure decreased 32.7% from 454.7 per 100 000 people in 1997 to 306.1 per 100 000 people in 2007 (p < 0.001). A comparable decrease in incidence occurred in both inpatient and outpatient settings. The greatest relative decrease occurred in patients aged 85 and over. Over the study period, 1-year risk-adjusted mortality decreased from 17.7% in 1997 to 16.2% in 2007 (p = 0.02) for outpatients, with a nonsignificant decrease from 35.7% in 1997 to 33.8% in 2007 (p = 0.1) for inpatients.

Interpretation:

The incidence of heart failure decreased substantially during the study period. Nevertheless, the prognosis for patients with heart failure remains poor and is associated with high mortality.Heart failure is a leading cause of admission to hospital and is associated with a poor long-term prognosis. In 1996, it was projected that the number of incident hospital admissions for heart failure in Canada would more than double by 2025 because of the aging population and increasing numbers of myocardial infarction survivors.¹ By 2000, patients with heart failure accounted for the second highest number of hospital days in Canada, and the estimated 1-year case-fatality rate, after the first hospital admission, exceeded 35%.^2,3 However, some recent studies suggest that admission and mortality rates for heart failure may actually be falling. It is unclear whether these changes represent lower rates of new incident cases, fewer readmissions, a shift to more outpatient care or improved survival.^4,5We sought to examine temporal trends in the incidence and outcomes of heart failure in Ontario, Canada, in both inpatient and outpatient settings to assess the progress made in reducing the population burden of heart failure and to gain insight into the effectiveness of current preventive and therapeutic strategies.     

Uncovering heart failure with preserved ejection fraction in patients with type 2 diabetes in primary care: time for a change

Undetected heart failure appears to be an important health problem in patients with type 2 diabetes and aged ≥ 60 years. The prevalence of previously unknown heart failure in these patients is high, steeply rises with age, and is overall higher in women than in men. The majority of the patients with newly detected heart failure have a preserved ejection fraction. A diagnostic algorithm to detect or exclude heart failure in these patients with variables from the medical files combined with items from history taking and physical examination provides a good to excellent accuracy. Annual screening appears to be cost-effective. Both unrecognised heart failure with reduced and with preserved ejection fraction were associated with a clinically relevant lower health status in patients with type 2 diabetes. Also the prognosis of these patients was worse than of those without heart failure. Existing disease-management programs for type 2 diabetes pay insufficient attention to early detection of cardiovascular diseases, including heart failure. We conclude that more attention is needed for detection of heart failure in older patients with type 2 diabetes.     

Joint Impact of Clinical and Behavioral Variables on the Risk of Unplanned Readmission and Death after a Heart Failure Hospitalization

Most current methods for modeling rehospitalization events in heart failure patients make use of only clinical and medications data that is available in the electronic health records. However, information about patient-reported functional limitations, behavioral variables and socio-economic background of patients may also play an important role in predicting the risk of readmission in heart failure patients. We developed methods for predicting the risk of rehospitalization in heart failure patients using models that integrate clinical characteristics with patient-reported functional limitations, behavioral and socio-economic characteristics. Our goal was to estimate the predictive accuracy of the joint model and compare it with models that make use of clinical data alone or behavioral and socio-economic characteristics alone, using real patient data. We collected data about the occurrence of hospital readmissions from a cohort of 789 heart failure patients for whom a range of clinical and behavioral characteristics data is also available. We applied the Cox model, four different variants of the Cox proportional hazards framework as well as an alternative non-parametric approach and determined the predictive accuracy for different categories of variables. The concordance index obtained from the joint prediction model including all types of variables was significantly higher than the accuracy obtained from using only clinical factors or using only behavioral, socioeconomic background and functional limitations in patients as predictors. Collecting information on behavior, patient-reported estimates of physical limitations and frailty and socio-economic data has significant value in the predicting the risk of readmissions with regards to heart failure events and can lead to substantially more accurate events prediction models.     

Prognosis Analysis of Heart Failure Based on Recurrent Attention Model

ObjectivesHeart failure is a group of complex clinical syndromes that lead to ventricular filling or impaired ejection ability due to abnormal heart structure or function. Difficult treatment, poor prognosis and high mortality are the main characteristics of heart failure. According to admission data and past medical use, the 30-day mortality rate of patients with heart failure was obtained and the main characteristics affecting the 30-day mortality of patients with heart failure were determined.Material and methodsBased on the data of April 2016 to July 2018 of Shanxi Acadeny of Medical Sciences, and we chose 4,682 information on heart failure patients, of which 539 died in the hospital by screening. We built a 30-day mortality prediction model for patients with heart failure. The model can fuse clinical data and text data through multiple kernel learning, and input the fused data into the recurrent attention model. It can not only predict the 30-day mortality of patients with heart failure, but also the influencing factors of prognosis of patients with heart failure were also obtained.ResultsThe prediction accuracy of the recurrent attention network is obviously higher than that of other machine learning models, and the accuracy rate reaches 93.4%. The AUC value of the area under the ROC curve of the model reaches 87%, which is obviously higher than that of the traditional machine learning models such as decision tree, naive Bayesian and support vector machine. In addition, the model can also reach a conclusion that New York heart function classification, age, NT—ProBNP, LVEF, β-blockers, ventricular arrhythmia, high blood pressure, coronary heart disease (CHD) and bronchitis were independent risk factors for death. And patients with revascularization, ACEI/ARB drugs, β-blockers, spironolactone have a better prognosis than non-users. This provides an important reference for doctors to better treat and manage patients with heart failure.ConclusionExperiments show that the prognostic effect of the recurrent attention model is significantly higher than that of other traditional machine learning models. Because the model increases the attention mechanism, the important features affecting the prognostic results are obtained, which enables doctors to prescribe drugs according to the symptoms, take timely precautions and help patients to treat in time.     

Endogenous cardiotonic steroids and cardiovascular disease,where to next?

Ever since British Physician William Withering first described the use of foxglove extract for treatment of patients with congestive heart failure in 1785, cardiotonic steroids have been used clinically to treat heart failure and more recently atrial fibrillation. Due to their ability to bind and inhibit the ubiquitous transport enzyme sodium potassium pump, thus regulating intracellular Na⁺ concentration in every living cell, they are also an essential tool for research into the sodium potassium pump structure and function. Exogenous CTS have been clearly demonstrated to affect cardiovascular system through modulation of vagal tone, cardiac contraction (via ionic changes) and altered natriuresis. Reports of a number of endogenous CTS, since the 1980s, have intensified research into their physiologic and pathophysiologic roles and opened up novel therapeutic targets. Substantive evidence pointing to the role of endogenous ouabain and marinobufagenin, the two most prominent CTS, in development of cardiovascular disease has accumulated. Nevertheless, their presence, structure, biosynthesis pathways and even mechanism of action remain unclear or controversial. In this review the current state-of-the-art, the controversies and the remaining questions surrounding the role of endogenous cardiotonic steroids in health and disease are discussed.     

The post-infarction nurse practitioner project

Objectives To confirm the feasibility of nurse practitioner interventionin non-high-risk patients with recent myocardial infarction (MI). Design Observational study. Setting Acute coronary care unit in a teaching hospital. Methods We performed an open-label feasibility study to identify non-high-risk MI patients and evaluate the outcome of a new nurse practitioner intervention programme. The initial pilot phase served to identify the non-high-risk population. In the subsequent confirmation phase, 500 consecutive non-high-risk post-MI patients with preserved LV function without heart failure were included to receive nurse practitioner management. The nurse practitioner intervention started on transfer from the coronary care unit to the cardiology ward and continued thereafter for up to 30 days. Main outcome measures Time to first event analysis of death from all causes or repeat myocardial infarction. Results 500 Patients without signs of heart failure or depressed LV function were identified as nonhigh- risk and eligible for inclusion in the nurse practitioner intervention programme. In the implementation phase, none of the patients died and 0.9% developed a repeat myocardial infarction after 30 days of follow-up. Compared with the pilot phase, patients in the implementation phase spent fewer days in hospital (mean 11.1 versus 6.2 days; p<0.001). Conclusion It is feasible to identify non-high-risk post-MI patients, who can be managed adequately by a nurse practitioner. Embedding experienced nurse practitioners within critical care pathways may result in significant decreases in length of hospital stay. (Neth Heart J 2009;17:61-7.)     

Metabolic modulation and cellular therapy of cardiac dysfunction and failure

At present the prevalence of heart failure rises along with aging of the population. Current heart failure therapeutic options are directed towards disease prevention via neurohormonal antagonism (β-blockers, angiotensin converting enzyme inhibitors and/or angiotensin receptor blockers and aldosterone antagonists), symptomatic treatment with diuretics and digitalis and use of biventricular pacing and defibrillators in a special subset of patients. Despite these therapies and device interventions heart failure remains a progressive disease with high mortality and morbidity rates. The number of patients who survive to develop advanced heart failure is increasing. These patients require new therapeutic strategies. In this review two of emerging therapies in the treatment of heart failure are discussed: metabolic modulation and cellular therapy. Metabolic modulation aims to optimize the myocardial energy utilization via shifting the substrate utilization from free fatty acids to glucose. Cellular therapy on the other hand has the goal to achieve true cardiac regeneration. We review the experimental data that support these strategies as well as the available pharmacological agents for metabolic modulation and clinical application of cellular therapy.     

Twenty-four hour monitoring of heart rate and activity in patients with diabetes mellitus: a comparison with clinic investigations.

Heart rate and activity were recorded continuously in 11 selected diabetics during a normal day, and the observations were compared with results obtained in the same patients in the diabetic outpatient clinic 10 months earlier. Both sets of findings agreed well in heart rate variability and postural tachycardia. In patients with well-controlled diabetes simple tests of reflex cardiovascular control produce results that may be useful in following the course of diabetic autonomic neuropathy.     

End-stage heart failure and mechanical circulatory support: feasibility of discharge from hospital

Background. Due to the shortage of donor hearts, mechanical circulatory support is increasingly being used as a bridge to transplantation. In order to allow for more widespread use of ventricular assist devices it is mandatory that patients are not continuously hospitalised. We present the results of our experience with patients with end-stage heart failure, discharged from hospital after implantation of a ventricular assist device and followed in an outpatient setting. Methods. After an intensive training and education programme, focusing on the management of the percutaneous driveline and instructions on how to handle in case of an alarm or malfunction of the device, patients were discharged. They were followed in the outpatient department. All regular and unplanned visits were registered, including readmissions. Results. Twenty-seven patients treated with a ventricular assist device were discharged from hospital. There were 37 extra visits, of these, 27 were device related resulting in 21 readmissions (0.78/patient). We treated eight infectious episodes in four patients, all device related. Furthermore seven thromboembolic episodes occurred in four patients. One patient died because of multiorgan failure seven weeks after he was readmitted with an urosepsis. In our experience of 11.4 patient years at home while on the device, only 5% of the time was spent in hospital for complications. In comparison with patients on an assist device who stayed in hospital until transplantation, there were no more complications. Conclusion. This study demonstrates that patients with end-stage heart failure, treated with a ventricular assist device, can be safely discharged from hospital, with an acceptable rate of readmissions. It results in a fair quality of life, with a high degree of independence of the patient. (Neth Heart J 2007; 15:45-50.)     

Automated birdsong recognition in complex acoustic environments: a review

Conservationists are increasingly using autonomous acoustic recorders to determine the presence/absence and the abundance of bird species. Unlike humans, these recorders can be left in the field for extensive periods of time in any habitat. Although data acquisition is automated, manual processing of recordings is labour intensive, tedious, and prone to bias due to observer variations. Hence automated birdsong recognition is an efficient alternative. However, only few ecologists and conservationists utilise the existing birdsong recognisers to process unattended field recordings because the software calibration time is exceptionally high and requires considerable knowledge in signal processing and underlying systems, making the tools less user‐friendly. Even allowing for these difficulties, getting accurate results is exceedingly hard. In this review we examine the state‐of‐the‐art, summarising and discussing the methods currently available for each of the essential parts of a birdsong recogniser, and also available software. The key reasons behind poor automated recognition are that field recordings are very noisy, calls from birds that are a long way from the recorder can be faint or corrupted, and there are overlapping calls from many different birds. In addition, there can be large numbers of different species calling in one recording, and therefore the method has to scale to large numbers of species, or at least avoid misclassifying another species as one of particular interest. We found that these areas of importance, particularly the question of noise reduction, are amongst the least researched. In cases where accurate recognition of individual species is essential, such as in conservation work, we suggest that specialised (species‐specific) methods of passive acoustic monitoring are required. We also believe that it is important that comparable measures, and datasets, are used to enable methods to be compared.     

Out-of-hours visits in a group practice.

In one year 1644 out-of-hours calls were undertaken by a partnership of eight doctors working in a deprived inner urban area and a deprived large council housing estate; of these calls 332 were performed between the hours of 11 pm and 7 am. The number of calls required in the housing estate, 1077, was about twice as many as in the inner urban area, although the same doctors were using the same criteria for a visit. The rate of visits of 107 per 1000 patients in the housing estate was much higher than in other published series. The reasons for this difference appeared to be related to the comparative youth of parents and the number of young children.