The Incremental Value of Magnetic Resonance Imaging for Identification of Apical Pouch in Patients with Apical Variant of Hypertrophic Cardiomyopathy.

BACKGROUND: The development of a left ventricular (LV) apical pouch in patients with apical hypertrophic cardiomyopathy (aHCM) has been thought to be the transition point that can become an apical aneurysm, which is linked to higher risk of adverse events. In our study, we sought to compare the ability of transthoracic echocardiography (echo) and cardiac magnetic resonance imaging (cMRI) to accurately identify the presence of an apical pouch or aneurysm in patients with aHCM. METHODS: We retrospectively reviewed the charts of all consecutive patients that had features of aHCM on imaging. Data from cMRI and echo examinations were abstracted, and the ability of these diagnostic modalities to identify the presence of a LV apical pouch and aneurysm was analyzed. RESULTS: Of 31 patients with aHCM, 17 (54.8%) had an apical pouch and 2 were found to have apical aneurysm (6.5%) on cMRI. Echo with and without perflutren contrast was able to accurately identify both aneurysms, but only 47.1% (8/17) of apical pouches seen by cMRI. Two patients had apical thrombus that was identified by cMRI, but not by echo. CONCLUSION: Our findings indicate that cMRI is superior to echo in identifying apical pouches in patients with aHCM. Our results also suggest that in patients undergoing echo, the use of perflutren contrast for LV opacification increases the diagnostic yield. Further study is necessary to delineate whether earlier identification of an apical pouch will be of clinical benefit for patients with aHCM by altering clinical management and avoiding adverse cardiovascular events.

Chest pain and diarrhea: a case of Campylobacter jejuni-associated myocarditis.

BACKGROUND: Diarrhea and chest pain are common symptoms in patients presenting to the emergency department (ED). However, rarely is a relationship between these two symptoms established in a single patient. OBJECTIVE: Describe a case of Campylobacter-associated myocarditis. CASE REPORT: A 43-year-old man with a history of hypertension presented to the ED with angina-like chest pain and a 3-day history of diarrhea. Electrocardiogram revealed ST-segment elevation in the lateral leads. Coronary angiogram revealed no obstructive coronary artery disease. Troponin T rose to 1.75 ng/mL. Cardiac magnetic resonance imaging showed subepicardial and mid-myocardial enhancement, particularly in the anterolateral wall and interventricular septum, consistent with a diagnosis of myocarditis. Stool studies were positive for Campylobacter jejuni. CONCLUSIONS: Campylobacter-associated myocarditis is rare, but performing the appropriate initial diagnostic testing, including stool cultures, is critical to making the diagnosis. Identifying the etiology of myocarditis as bacterial will ensure that appropriate treatment with antibiotics occurs in addition to any cardiology medications needed for supportive care.

It begins with the right supervisor: importance of mentorship and clinician-investigator trainee satisfaction levels in Canada.

PURPOSE: Clinician Investigator Trainee Association of Canada/ Association des cliniciens-chercheurs en formation du Canada (CITAC/ACCFC) represents the interests of clinician-investigator (CI) trainees across Canada. To better advocate for the successful training of CI trainees in Canada, CITAC/ACCFC conducted a survey to assess satisfaction with their training and to find what factors were most associated with satisfaction level. METHODS: A nominal scale-based psychometric survey was conducted online in 2009 on CI trainees in Canada (including MD/MSc, MD/PhD, or CIP/SSP). One hundred fifteen out of a target population of approximately 350-400 responded. Survey respondents were asked to rate their level of satisfaction in four areas: 1) quality of training, 2) financial support, 3) mentorship satisfaction and 4) program structure. Ratings in these four areas were also combined to produce a measure of overall satisfaction. RESULTS: At least half of the respondents were 'completely satisfied' in each of the four categories other than mentorship. While 98% of respondents considered mentorship as important to their success, 62% expressed some level of dissatisfaction with the level of mentorship received. Moreover, increased levels of mentorship were strongly associated with increased levels of overall satisfaction. CONCLUSION: The discrepancy between CI trainees' perceived importance of mentorship and the level of satisfaction in mentorship received reveals a strategic area where CI training should be improved. Recognizing that good mentorship in a CI training program often begins with one's research supervisor, the CITAC/ACCFC has compiled six specific recommendations for finding a good supervisor.

Effects of risk factors on evoked pain patterns in rat models of experimental knee osteoarthritis.

Pain experiences in patients with knee osteoarthritis (OA) may be influenced differently by OA risk factors, reducing the translatability of preclinical research into the clinic. Our objective was to contrast evoked pain patterns after exposure to different OA risk factors including acute joint trauma, chronic instability, or obesity/metabolic syndrome using rat models of experimental knee OA. We tested longitudinal patterns of evoked pain behaviors (knee pressure pain threshold and hindpaw withdrawal threshold) in young male rats exposed to different OA-inducing risk factors including (1) nonsurgical joint trauma (impact-induced anterior cruciate ligament (ACL) rupture); (2) surgical joint destabilization (ACL + medial meniscotibial ligament transection); and (3) high fat/sucrose (HFS) diet-induced obesity. Histopathology for synovitis, cartilage damage, and subchondral bone morphology was performed. Pressure pain threshold was reduced (more pain) most, and earlier by joint trauma (Week 4-12) and HFS (Week 8-28) than by joint destabilization (Week 12). Hindpaw withdrawal threshold was reduced transiently after joint trauma (Week 4), with smaller and later reductions after joint destabilization (Week 12), but not with HFS. Synovial inflammation occurred at Week 4 after joint trauma and instability but only coincided with pain behaviors after joint trauma. Cartilage and bone histopathology were most severe after joint destabilization and least severe with HFS. The pattern, intensity, and timing of evoked pain behaviors varied due to OA risk factor exposure and were inconsistently associated with histopathological OA features. These findings may help to explain the challenges with translating preclinical OA pain research to multimorbid clinical OA contexts.

Transcatheter Aortic Valve Replacement Prognostication with Augmented Mean Arterial Pressure.

BACKGROUND: Post-transcatheter aortic valve replacement (TAVR) patient outcome is an important research topic. To accurately assess post-TAVR mortality, we examined a family of new echo parameters (augmented systolic blood pressure (AugSBP) and arterial mean pressure (AugMAP)) derived from blood pressure and aortic valve gradients. METHODS: Patients in the Mayo Clinic National Cardiovascular Diseases Registry-TAVR database who underwent TAVR between 1 January 2012 and 30 June 2017 were identified to retrieve baseline clinical, echocardiographic and mortality data. AugSBP, AugMAP and valvulo-arterial impedance (Zva) (Zva) were evaluated using Cox regression. Receiver operating characteristic curve analysis and the c-index were used to assess the model performance against the Society of Thoracic Surgeons (STS) risk score. RESULTS: The final cohort contained 974 patients with a mean age of 81.4 ± 8.3 years old, and 56.6% were male. The mean STS risk score was 8.2 ± 5.2. The median follow-up duration was 354 days, and the one-year all-cause mortality rate was 14.2%. Both univariate and multivariate Cox regression showed that AugSBP and AugMAP parameters were independent predictors for intermediate-term post-TAVR mortality (all p < 0.0001). AugMAP1 < 102.5 mmHg was associated with a 3-fold-increased risk of all-cause mortality 1-year post-TAVR (hazard ratio 3.0, 95%confidence interval 2.0-4.5, p < 0.0001). A univariate model of AugMAP1 surpassed the STS score model in predicting intermediate-term post-TAVR mortality (area under the curve: 0.700 vs. 0.587, p = 0.005; c-index: 0.681 vs. 0.585, p = 0.001). CONCLUSIONS: Augmented mean arterial pressure provides clinicians with a simple but effective approach to quickly identify patients at risk and potentially improve post-TAVR prognosis.

Using Augmented Mean Arterial Pressure to Identify High Mortality Risk Patients With Moderate Aortic Stenosis.

OBJECTIVE: To study the usefulness of a novel echocardiographic marker, augmented mean arterial pressure (AugMAP = [(mean aortic valve gradient + systolic blood pressure) + (2 × diastolic blood pressure)] / 3), in identifying high-risk patients with moderate aortic stenosis (AS). PATIENTS AND METHODS: Adults with moderate AS (aortic valve area, 1.0-1.5 cm2) at Mayo Clinic sites from January 1, 2010, through December 31, 2020, were identified. Baseline demographic, echocardiographic, and all-cause mortality data were retrieved. Patients were grouped into higher and lower AugMAP groups using a cutoff value of 80 mm Hg for analysis. Kaplan-Meier and Cox regression models were used to assess the performance of AugMAP. RESULTS: A total of 4563 patients with moderate AS were included (mean ± SD age, 73.7±12.5 years; 60.5% men). Median follow-up was 2.5 years; 36.0% of patients died. The mean ± SD left ventricular ejection fraction (LVEF) was 60.1%±11.4%, and the mean ± SD AugMAP was 99.1±13.1 mm Hg. Patients in the lower AugMAP group, with either preserved or reduced LVEF, had significantly worse survival performance (all P<.001). Multivariate Cox regression showed that AugMAP (hazard ratio, 0.962; 95% CI, 0.942 to 0.981 per 5-mm Hg increase; P<.001) and AugMAP less than 80 mm Hg (hazard ratio, 1.477; 95% CI, 1.241 to 1.756; P<.001) were independently associated with all-cause mortality. CONCLUSION: AugMAP is a simple and effective echocardiographic marker to identify high-risk patients with moderate AS independent of LVEF. It can potentially be used in the candidate selection process if moderate AS becomes indicated for aortic valve intervention in the future.

Developing an Echocardiography-Based, Automatic Deep Learning Framework for the Differentiation of Increased Left Ventricular Wall Thickness Etiologies.

AIMS: Increased left ventricular (LV) wall thickness is frequently encountered in transthoracic echocardiography (TTE). While accurate and early diagnosis is clinically important, given the differences in available therapeutic options and prognosis, an extensive workup is often required to establish the diagnosis. We propose the first echo-based, automated deep learning model with a fusion architecture to facilitate the evaluation and diagnosis of increased left ventricular (LV) wall thickness. METHODS AND RESULTS: Patients with an established diagnosis of increased LV wall thickness (hypertrophic cardiomyopathy (HCM), cardiac amyloidosis (CA), and hypertensive heart disease (HTN)/others) between 1/2015 and 11/2019 at Mayo Clinic Arizona were identified. The cohort was divided into 80%/10%/10% for training, validation, and testing sets, respectively. Six baseline TTE views were used to optimize a pre-trained InceptionResnetV2 model. Each model output was used to train a meta-learner under a fusion architecture. Model performance was assessed by multiclass area under the receiver operating characteristic curve (AUROC). A total of 586 patients were used for the final analysis (194 HCM, 201 CA, and 191 HTN/others). The mean age was 55.0 years, and 57.8% were male. Among the individual view-dependent models, the apical 4-chamber model had the best performance (AUROC: HCM: 0.94, CA: 0.73, and HTN/other: 0.87). The final fusion model outperformed all the view-dependent models (AUROC: HCM: 0.93, CA: 0.90, and HTN/other: 0.92). CONCLUSION: The echo-based InceptionResnetV2 fusion model can accurately classify the main etiologies of increased LV wall thickness and can facilitate the process of diagnosis and workup.

Effect of positional changes on inferior vena cava size.

AIM: To study the effect of positional change on inferior vena cava (IVC) diameter. The influence of positional change on IVC size is not well studied. Although the American Society of Echocardiography guidelines for chamber quantification recommend imaging the IVC in the left lateral position, many labs routinely image the IVC from the supine position. METHODS AND RESULTS: Forty-three patients (age 39.5 ± 9.4) with normal echocardiographic findings were studied. Subcostal imaging was used to assess the IVC in the supine and left lateral positions. IVC dimensions, hepatic vein (HV) Doppler and tricuspid regurgitation (TR) jet velocity were measured. IVC systolic and diastolic dimensions were larger in the supine compared with the left lateral position (17.2 ± 4.1 vs. 10.9 ± 4.4 mm, P < 0.001; 16.2 ± 4.5 vs. 9.9 ± 4.4 mm, P < 0.001, respectively). Position had no influence on HV systolic and diastolic peak velocity. (35.4 ± 23.7 vs. 31.8 ± 35.0 cm/s, P = 0.461; 24.2 ± 19.5 vs. 25.4 ± 31.9 cm/s, P = 0.775, respectively). CONCLUSIONS: The IVC dimension is larger in the supine position independent of the cardiac cycle. This may be due to increased intra-abdominal pressure and compression of the IVC by the liver in the left lateral position. HV systolic and diastolic peak Doppler velocities were not influenced by position.

Multimodality imaging showing complete cardiovascular involvement by Erdheim-Chester disease.

Erdheim-Chester disease (ECD) is a multisystem non-Langerhans form of cell histiocytosis. Histiocytic infiltration leads to xanthogranulomatous infiltrates of multiple organ systems. Erdheim-Chester disease was first reported in 1930, only 320 cases reported in the literature. Cardiac involvement in ECD carries worst prognosis beside the central nervous system. We report the first case with pan-cardiac involvement diagnosed with multimodality imaging.

Environmental contamination and risk factors for geohelminth transmission in three informal settlements in Durban metropole, South Africa.

Informal settlements/slums are characterised by a lack of adequate sanitation and safe drinking water. Contaminated soil and water sources combined with poor hygiene and environmental conditions results in the transmission of soil transmitted helminths to humans. The aim of the present study was to assess environmental contamination and risk factors for geohelminth transmission in three informal settlements in Durban, South Africa. Each settlement had different types of sanitation facilities namely; flush toilets, pit latrines and chemical toilets. Thirty adult members from 30 households from each settlement were interviewed to determine their knowledge, attitudes and behaviour on geohelminth transmission. Furthermore, two hundred soil samples were collected from areas considered potential sources of infection and processed for the detection and identification of geohelminth eggs. Prevalence and intensities of geohelminth infections from school-age children were also assessed. From the total collection in the three settlements, 31.6% (95/190) were positive for geohelminth eggs with Ascaris lumbricoides, Trichuris trichiura and Taenia spp. eggs being recovered. Quarry Road West (57%; 114/200) showed the highest levels of soil contamination followed by Briardene (27%; 54/200) and Smithfield (11%; 22/200). Stool samples collected from 135 children were found to contain parasite eggs of A. lumbricoides and T. trichiura. Prevalences and intensities of infection were highest in Quarry Road West for both A. lumbricoides (42%, 57/135; 6.0eggs/g) and T. trichiura (10%, 14/135; 1.9eggs/g) and 9.6% (13/135) harboured dual infections. Open defaecation by community members was observed as the main contributing factor for the presence of geohelminth eggs in soil.

Impact of community piped water coverage on re-infection with urogenital schistosomiasis in rural South Africa.

Previously, we demonstrated that coverage of piped water in the seven years preceding a parasitological survey was strongly predictive of Schistosomiasis haematobium infection in a nested cohort of 1976 primary school children (Tanser, 2018). Here, we report on the prospective follow up of infected members of this nested cohort (N = 333) for two successive rounds following treatment. Using a negative binomial regression fitted to egg count data, we found that every percentage point increase in piped water coverage was associated with 4.4% decline in intensity of re-infection (incidence rate ratio = 0.96, 95% CI: 0.93-0.98, p=0.004) among the treated children. We therefore provide further compelling evidence in support of the scaleup of piped water as an effective control strategy against Schistosoma haematobium transmission.

Preoperative dobutamine stress echocardiographic findings and subsequent short-term adverse cardiac events after orthotopic liver transplantation.

Cardiovascular (CV) complications are the leading cause of non-graft-related death in orthotopic liver transplant (OLT) patients. Pretransplant cardiac evaluation using dobutamine stress echocardiography (DSE) is commonly utilized for risk stratification of OLT candidates. To determine if clinical and echocardiographic variables identify patients with increased CV risk, we performed a retrospective chart review of all 284 patients that underwent OLT at our institution between June 1999 and August 2005. Of these patients, 157 had a DSE prior to their OLT. Serious adverse CV events occurring during surgery and up to 4 months post-transplantation were defined as cardiac-related death, myocardial infarction (MI), new heart failure, or asystole or unstable ventricular arrhythmia requiring acute treatment. Sixteen of 157 patients (10%) had an adverse CV event with 2 deaths. These included ventricular tachycardia (n = 8), asystole (n = 2), MI (n = 5), and new heart failure (n = 1). Nine of the 16 CV events occurred at the time of surgery (including both deaths), 5 occurred postoperatively, and 3 occurred after hospital discharge. Variables that correlated with increased CV events were inability during DSE to achieve >82% of the maximum predicted heart rate (22% versus 6%, P = 0.01), a peak rate pressure product during DSE of <16,333 (17% versus 5%, P = 0.02), and a Model for End-Stage Liver Disease (MELD) score of >24 at the time of OLT. A multivariate model calculated from the DSE maximum achieved heart rate (MAHR) and MELD score (result = 3.78 + 0.07 MELD - 0.05 MAHR) identified a 47% risk for a value > 0 versus a 6% risk for a value < 0 (P < 0.001). In conclusion, the maximum heart rate achieved during DSE together with the MELD score may be a predictor of adverse CV events up to 4 months post-OLT. A large prospective study is needed to more decisively support this conclusion.

Echocardiographic assessment of left ventricular diastolic function and filling pressure in atrial fibrillation.

Diastolic dysfunction has been linked to 2 epidemics: atrial fibrillation (AF) and heart failure. The presence and severity of diastolic dysfunction are associated with an increased risk for first AF and first heart failure in patients with sinus rhythm. Furthermore, the risk for heart failure is markedly increased once AF develops. The evaluation of diastolic function once AF has developed remains a clinical challenge. The conventional use of Doppler echocardiography for the assessment and grading of diastolic dysfunction relies heavily on evaluating the relation of ventricular and atrial flow characteristics. The mechanical impairment of the left atrium and the variable cycle lengths in AF render the evaluation of diastolic function difficult. A few Doppler echocardiographic methods have been proved clinically useful for the estimation of diastolic left ventricular filling pressures in AF, but these appear to be underutilized. Several innovative methods are emerging that promise to provide greater precision in diastolic function assessment, but their clinical utility in AF remains to be established. In conclusion, this review provides an up-to-date discussion of the evaluation of diastolic function assessment in AF and how it may be important in the clinical management of patients with AF.

Impact of the scale-up of piped water on urogenital schistosomiasis infection in rural South Africa.

Recent work has estimated that sub-Saharan Africa could lose US$3.5 billion of economic productivity every year as a result of schistosomiasis and soil-transmitted helminthiasis. One of the main interventions to control schistosomiasis is the provision of safe water to limit the contact with infected water bodies and break the cycle of transmission. To date, a rigorous quantification of the impact of safe water supplies on schistosomiasis is lacking. Using data from one of Africa's largest population-based cohorts, we establish the impact of the scale-up of piped water in a typical rural South African population over a seven-year time horizon. High coverage of piped water in the community decreased a child's risk of urogenital schistosomiasis infection eight-fold (adjusted odds ratio = 0.12, 95% CI 0.06-0.26, p<0.001). The provision of safe water could drive levels of urogenital schistosomiasis infection to low levels of endemicity in rural African settings.

Predictors of Trypanosoma lewisi in Rattus norvegicus from Durban, South Africa.

This study investigated associations between Trypanosoma lewisi and Xenopsylla cheopis, a common cyclical vector of T. lewisi; Polyplax spinulosa, a reported mechanical vector; and Laelaps echidnina and Laelaps lamborni, 2 rodent mites of Rattus norvegicus in Durban, South Africa. In total, 379 R. norvegicus individuals were live-trapped at 48 sites in 4 locality types around Durban during a 1-yr period. Rats were euthanized, cardiac blood was taken to check for hemoparasites, and ectoparasites were removed for identification. Parasite species richness was higher in pups (2.11) and juveniles (1.02) than adults (0.87). Most rats in the study harbored 1 or 2 of the 5 parasites surveyed. Rats with trypanosomes and fleas were more prevalent in the city center and harbor, where juveniles were most affected. Rats with lice were more prevalent in informal settlements and urban/peri-urban areas, where pups had the highest infestations. There was a significant positive association between rats with fleas and trypanosomes and a negative association between rats with lice and trypanosomes. Location and rat age were significant predictors of T. lewisi, X. cheopis, and P. spinulosa. Mites showed no strong association with trypanosomes. Ectoparasite associations are possibly habitat and life-cycle related. We conclude that Durban's city center, which offers rats harborage, an unsanitary environment, and availability of food, is a high-transmission area for fleas and trypanosomes, and consequently a potential public health risk.

Effects of Pectus Excavatum Repair on Right and Left Ventricular Strain.

BACKGROUND: The cardiopulmonary benefits of pectus excavatum repair have been debated. Echocardiographic speckle-tracking strain and strain rate have been used to evaluate and detect subclinical myocardial dysfunction in patients receiving cardiotoxic chemotherapy, and patients with valvular heart disease. This technology was applied to evaluate the effects of pectus excavatum surgery on left ventricular (LV) and right ventricular (RV) function. METHODS: Speckle tracing strain evaluation was performed on intraoperative transesophageal echocardiographic images acquired immediately before and after Nuss repair in adult patients (aged 18 years or more) from 2011 to 2014. Standard severity and compression indices were measured on chest imaging performed before pectus excavatum repair. RESULTS: In total, 165 patients with transesophageal echocardiographic images during repair were reviewed (71.5% male; mean age 33.0 years; range, 18 to 71; Haller index 5.7; range, 2.3 to 24.3). Significant improvement after repair was seen in global RV longitudinal strain (-13.5% ± 4.1% to -16.7% ± 4.4%, p < 0.0001) and strain rate (-1.3 ± 0.4 s-1 to -1.4 ± 0.4 s-1, p = 0.0102); LV global circumferential strain (-18.7% ± 5.7% to -23.5% ± 5.8%, p < 0.0001) and strain rate (-1.5 ± 0.5 s-1 to -1.9 ± 0.8 s-1, p = 0.0003); and LV radial strain (24.1% ± 13.5% to 31.1% ± 16.4%, p = 0.0050). There was a strong correlation between preoperative right atrial compression on transesophageal echocardiogram and improvement in RV global longitudinal strain rate immediately after pectus repair. CONCLUSIONS: Mechanical compression and impaired RV and LV strain is improved by Nuss surgical repair of pectus deformity.

Relation of electrocardiographic criteria for left atrial enlargement to two-dimensional echocardiographic left atrial volume measurements.

Left atrial (LA) enlargement by 2-dimensional (2-D) echocardiography predicts adverse cardiovascular outcomes. Electrocardiographic (ECG) criteria for LA enlargement are based on M-mode echocardiographic LA diameter, which is inferior to 2-D-derived LA volumes. This study compared established ECG criteria for LA enlargement with atrial volume obtained by 2-D echocardiography to determine if traditional ECG criteria accurately represent LA chamber enlargement, therefore offering a low-cost screening tool. A total of 261 randomly selected patients who underwent electrocardiography and 2-D echocardiography were enrolled. ECG parameters and electronically derived P-wave medians were analyzed with electronic calipers for maximal accuracy. LA volumes by 2-D echocardiography were measured with Simpson's method of discs, with enlargement defined as 32 ml/m(2). Sensitivity and specificity tables and receiver-operating characteristic curves were constructed for each criterion. Univariate and multivariate analyses were performed for predictors of 2-D echocardiographic LA enlargement. LA enlargement was present in 43% of patients. ECG P-wave duration was the most sensitive for the detection of LA enlargement (69%) but had low specificity (49%). Conversely, a biphasic P wave was the most specific (92%) but had low sensitivity (12%). The maximum area under the receiver-operating characteristic curve for any criterion was 0.64, too low to be of clinical utility. In conclusion, established ECG criteria for LA enlargement do not reliably reflect LA enlargement and lack sufficient predictive value to be useful clinically. These results suggest that P-wave abnormalities should be noted as nonspecific LA abnormalities, with the term "LA enlargement" no longer used.

Choice of treatment for fever at household level in Malawi: examining spatial patterns.

BACKGROUND: Although malaria imposes an enormous burden on Malawi, it remains a controllable disease. The key strategies for control are based on early diagnosis and prompt treatment with effective antimalarials. Its success, however, depends on understanding the factors influencing health care decision making at household level, which has implications for implementing policies aimed at promoting health care practices and utilization. METHODS: An analysis of patterns of treatment-seeking behaviour among care-givers of children of malarial fever in Malawi, based on the 2000 Malawi demographic and health survey, is presented. The choice of treatment provider (home, shop, or formal hospital care, others) was considered as a multi-categorical response, and a multinomial logistic regression model was used to investigate determinants of choosing any particular provider. The model incorporated random effects, at subdistrict level, to measure the influence of geographical location on the choice of any treatment provider. Inference was Bayesian and based on Markov chain Monte Carlo techniques. RESULTS AND CONCLUSION: Spatial variation was found in the choice of a provider and determinants of choice of any provider differed. Important risk factors included place of residence, access to media, care-giver's age and care factors including unavailability and inaccessibility of care. A greater effort is needed to improve the quality of malaria home treatment or expand health facility utilization, at all levels of administration if reducing malaria is to be realised in Malawi. Health promotion and education interventions should stress promptness of health facility visits, improved access to appropriate drugs, and accurate dosing for home-based treatments.

Geographical disparities in core population coverage indicators for roll back malaria in Malawi.

BACKGROUND: Implementation of known effective interventions would necessitate the reduction of malaria burden by half by the year 2010. Identifying geographical disparities of coverage of these interventions at small area level is useful to inform where greatest scaling-up efforts should be concentrated. They also provide baseline data against which future scaling-up of interventions can be compared. However, population data are not always available at local level. This study applied spatial smoothing methods to generate maps at subdistrict level in Malawi to serve such purposes. METHODS: Data for the following responses from the 2000 Malawi Demographic and Health Survey (DHS) were aggregated at subdistrict level: (1) households possessing at least one bednet; (2) children under 5 years who slept under a bednet the night before the survey; (3) bednets retreated with insecticide within past 6-12 months preceding the survey; (4) children under 5 who had fever two weeks before the survey and received treatment within 24 hours from the onset of fever; and (5) women who received intermittent preventive treatment of malaria during their last pregnancy. Each response was geographically smoothed at subdistrict level by applying conditional autoregressive models using Markov Chain Monte Carlo simulation techniques. RESULTS: The underlying geographical patterns of coverage of indicators were more clear in the smoothed maps than in the original unsmoothed maps, with relatively high coverage in urban areas than in rural areas for all indicators. The percentage of households possessing at least one bednet was 19% (95% credible interval (CI): 16-21%), with 9% (95% CI: 7-11%) of children sleeping under a net, while 18% (95% CI: 16-19%) of households had retreated their nets within past 12 months prior to the survey. The northern region and lakeshore areas had high bednet coverage, but low usage and re-treatment rates. Coverage rate of children who received antimalarial treatment within 24 hours after onset of fever was consistently low for most parts of the country, with mean coverage of 4.8% (95% CI: 4.5-5.0%). About 48% (95% CI: 47-50%) of women received antimalarial prophylaxis during their pregnancy, with highest rates in the southern and northern areas. CONCLUSION: The striking geographical patterns, for example between predominantly urban and rural areas, may reflect spatial differences in provider compliance or coverage, and can partly be explained by socio-economic and cultural differences. The wide gap between high bed net coverage and low retreatment rates may reflect variation in perceptions about malaria, which may be addressed by implementing information, education and communication campaigns or introducing long lasting insecticide nets. Our results demonstrate that DHS data, with appropriate methodology, can provide acceptable estimates at sub-national level for monitoring and evaluation of malaria control goals.

Modelling the effect of malaria endemicity on spatial variations in childhood fever, diarrhoea and pneumonia in Malawi.

BACKGROUND: Co-morbidity with conditions such as fever, diarrhoea and pneumonia is a common phenomenon in tropical Africa. However, little is known about geographical overlaps in these illnesses. Spatial modelling may improve our understanding of the epidemiology of the diseases for efficient and cost-effective control. METHODS: This study assessed subdistrict-specific spatial associations of the three conditions (fever, diarrhoea and pneumonia) in relation to malaria endemicity. We used data from the 2000 Malawi demographic and health survey which captured the history of childhood morbidities 2 weeks prior to the survey date. The disease status of each child in each area was the outcome of interest and was modelled using a trivariate logistic regression model, and incorporated random effects to measure spatial correlation. RESULTS: The risk of fever was positively associated with high and medium malaria endemicity levels relative to low endemicity level, while for diarrhoea and pneumonia we observed marginal positive association at high endemicity level relative to low endemicity level, controlling for confounding covariates and heterogeneity. A positive spatial correlation was found between fever and diarrhoea (r = 0.29); while weak associations were estimated between fever and pneumonia (r = 0.01); and between diarrhoea and pneumonia (r = 0.05). The proportion of structured spatial variation compared to unstructured variation was 0.67 (95% credible interval (CI): 0.31-0.91) for fever, 0.67 (95 % CI: 0.27-0.93) for diarrhoea, and 0.87 (95% CI: 0.62-0.96) for pneumonia. CONCLUSION: The analysis suggests some similarities in subdistrict-specific spatial variation of childhood morbidities of fever, diarrhoea and pneumonia, and might be a result of shared and overlapping risk factors, one of which is malaria endemicity.