The role of economies of scale in the cost of dialysis across the world: a macroeconomic perspective

BACKGROUND

The treatment of chronic kidney disease through dialysis is a considerable expense in most health systems. The two chief methods of providing dialysis, haemodialysis (HD) and peritoneal dialysis (PD) have significant differences in cost composition and factors of production. The aim of this article is to identify and quantify the macroeconomic variables that influence the relative cost of such modalities across different countries.

METHODS

From previously published literature, we extracted the estimates of HD/PD cost ratios in a total of 46 countries. We conducted a multivariate regression analysis using the estimated HD/PD cost ratio in each country, with several country level indicators as explanatory variables. We found a strong statistical effect of the following variables on the HD/PD cost ratio: country's level of development, economies of scale and percentage of private health-care expenditure.

RESULTS

The statistical effects on HD/PD ratio by local manufacturing and relaxed import regulation of PD equipment were calculated and were found to be very significant.

CONCLUSIONS

it is possible for a country to still reap the benefits of economies of scale in provision of PD, even in the absence of a large enough market to make local production of PD equipment feasible in that country.

Healthcare systems and chronic kidney disease: putting the patient in control

Today, health policy seems to be on the top of governments' agendas around the world. Healthcare systems are challenged by a number of phenomena happening on a global scale; these trends include demographic change in terms of an ageing population, an increase in chronic disease, patients having higher expectations on healthcare delivery and above all a major pressure on public finances to slow increasing healthcare expenditures. Such developments are forcing policy-makers to reform healthcare systems. First, there is a tendency towards decentralization of responsibilities. Second, governments are moving towards reimbursement schemes rewarding good outcomes and performance. Third, great importance is being attributed to transparency and accountability, and to introduce competition in healthcare. Fourth, attention is being shifted from simple treatment of a disease towards preventive initiatives, in a more holistic approach to health. Finally, healthcare policy-makers are recognizing the importance of empowering patients to give them control over decisions regarding their own health. These dynamics can be observed in chronic kidney disease, the management of which is a huge economic burden to healthcare systems globally, and which represents a good example of a field where important changes can be witnessed in therapy, technology, delivery and financing.

The use of in utero MRI to supplement ultrasound in the foetus at high risk of developmental brain or spine abnormality

OBJECTIVES

It is widely accepted that the diagnosis of foetal central nervous system (CNS) abnormalities can be improved by performing MRI examinations in utero. Most of the published literature has concentrated on pregnancies in which a developmental abnormality has been detected (or suspected) on ultrasound in an otherwise low-risk pregnancy. In this paper, we test the hypothesis that in utero MRI of the foetal brain in high-risk pregnancies will detect abnormalities not shown by ultrasound at a rate that justifies its use in clinical practice.

METHODS

100 females were recruited into the study from foeto-maternal or clinical genetic departments. They all had a foetus/child with a CNS malformation from an earlier pregnancy, which led to an increased risk of recurrence being quoted for the present pregnancy. All in utero MRI examinations were performed on 1.5 T clinical MRI systems at 18 weeks gestational age or later.

RESULTS

In 78% of cases, the ultrasound and MRI results agreed and showed no abnormality. In 13%, ultrasound and MRI described identical abnormal findings. In 9%, the ultrasound and MRI examinations had discrepant findings; in all these cases the MRI findings described more serious CNS pathology. The effects on management were judged to be major, by at least one assessor, in 7/9 of those cases.

CONCLUSION

As in many other situations involving antenatal detection of CNS abnormalities, in utero MRI should be considered in females with increased risk of foetal CNS malformation based on the results of an earlier pregnancy. Advances in knowledge In utero MRI of the foetus has an important role in antenatal diagnosis of females carrying a foetus with an increased risk of a brain abnormality.

An assessment of knowledge, attitudes and behaviour regarding the human papillomavirus

OBJECTIVES

This report is based on a study conducted in February 2010 that assessed the knowledge and attitudes toward cervical cancer and human papillomavirus (HPV) in Grenada which has a high incidence of cervical cancer.

METHODS

The participants were 71 students at the St George's University. There were 58 females and 13 males who participated in the study, a ratio of 4.5:1. Participants were asked to complete a survey on their knowledge and attitudes about HPV cervical cancer and the associated risk factors. Other evaluations of their levels of risk and Pap smear practices were also assessed.

RESULTS

The data reflected low knowledge and infrequent screening practices, from a public health perspective, when compared with developed countries. The data showed a significant deficit in knowledge of both males and females. Almost 95% of the women surveyed were able to correctly identify the purpose of a Pap smear as compared to 69.2% of the men surveyed. When the participants were asked what was the cause of cervical cancer 63.8% of women and 53.8% of males were correctly able to identify the HPV.

CONCLUSIONS

Enhanced educational programmes are needed to reduce the burden of cervical cancer that exists in Grenada.

The use of in utero MR imaging to delineate developmental brain abnormalities in multifetal pregnancies

BACKGROUND AND PURPOSE

iuMR has been shown to increase the detection rate of developmental abnormalities of the CNS, though most reports are limited to singleton pregnancies. The hypothesis tested in this study was that iuMR performed in multifetal pregnancies will show additional information about fetal CNS abnormalities in a similar proportion of cases when compared with singleton pregnancies.

MATERIALS AND METHODS

Fifty women with multifetal pregnancies were recruited consecutively carrying at least 1 fetus with a suspected developmental fetal CNS abnormality on sonography. All had iuMR at the same center by using the same MR imaging protocol. When the sonography and MR imaging reports were discrepant, 1 fetomaternal expert assessed the reports independently to predict in what percentage a change in prognosis/counseling would have occurred if iuMR was included in the diagnostic pathway.

RESULTS

There was agreement between the sonography and iuMR reports in 66% and disagreement in 34% of cases. The major cause for discrepancy was the presence or absence of the corpus callosum, which accounted for 10/17 of the disagreements. In 12/17 of the discrepant cases, the effect on management was judged to be significant.

CONCLUSIONS

We conclude that iuMR has a similar rate of discrepancy to sonography in multifetal pregnancies compared with the published data concerning singleton pregnancies. Our analysis of the effect on management shows that changes in the decision to consider termination of pregnancy would have occurred in 12/17 of the discrepant cases (ie, in 24% of our cases overall).

Brenneria salicis Associated with Watermark Disease Symptoms on Salix alba in Italy

From 1999 to 2010, withering of white willow was observed on trees growing along roads or irrigation canals in Torino, Alessandria, and Vercelli provinces of Italy, with incidence varying from 15, 25, and 30%, respectively. In spring and autumn 2008, six samples from withering branches with bark cankers were collected. On the bark surface near the cankers, iridescent traces of dried ooze were found. Tissues immediately below the cankers were dark with water-soaked, olive-colored edges. In some cases, the xylem appeared affected. Small fragments taken from the affected tissue on both edges of bark alterations and darkened vessels were crushed into mortars with sterile saline. Ten-fold serial dilutions (10^-1, 10^-2) were also performed. Aliquots of 0.1 ml were plated on nutrient agar and incubated at 25°C for 4 days. Bacterial colonies were ivory to white, circular, and bright, with a diameter of ~2 mm. Isolates were negative for Gram staining, presence of arginine dehydrolase, oxidase, phenylalanine deaminase, urease, hydrolysis of gelatin and starch, nitrate reduction, acidity from d-arabinose, cellobiose, lactose, maltose, trehalose, xylose, and pectinolytic activity on potato slices; positive for the presence of catalase and levan, fermentative metabolism of glucose, acid production from aesculin, l-arabinose, dextrose, d-galactose, inositol, d-mannitol, α-methylglucoside, raffinose, salicin and sucrose, H₂S production from cysteine, and bright yellow pigment production on autoclaved potato tissue. They were not fluorescent on King's medium B and did not induce hypersensitivity reaction on tobacco leaf. Similar results were obtained with Brenneria salicis control strain, LMG 6089, except for acid production from α-methylglucoside (negative) and l-arabinose (negative). Acid production from α-methylglucoside has been reported for the Japanese strains of B. salicis, which do not produce acidity from inositol (4). Genomic DNA was extracted (1) from three isolates, and PCR reactions were performed with Es1A and Es4B primers (2) that amplify a 553-bp fragment from the 16S rDNA of B. salicis. The isolates showed a PCR product of expected size, like the positive control LMB 6089. On the basis of colony features, biochemical tests, and the PCR assay, we conclude that the isolates belong to B. salicis, a pathogen reported in Belgium, Germany, Great Britain, the Netherlands, Hungary, Japan, and New Zealand (2,3) but, as well as watermark disease symptoms, never previously reported in Italy. In summer 2009, pathogenicity tests were performed by inoculating young, white willow plants with B. salicis suspensions of ~1 to 2 × 10⁹ CFU/ml placed with a syringe at the intersection of 1-year-old branches on the trunk. However, a year later, no symptoms of disease have been noted on the inoculated plants. According to the literature, pathogenicity tests rarely lead to the expected results because the bacterium can survive for many years in latent form, breaking out only when proper environmental conditions occur (3). Also the tests with B. salicis LMG 6089 gave negative results. Further investigation is necessary to clarify the relationships between this bacterium and the environment in causing withering of white willows in Piedmont. References: (1) W. P. Chen and T. T. Kuo. Nucleic Acids Res. 21:2260, 1993. (2) L. Hauben et al. Appl. Environ. Microbiol. 64:3966, 1998. (3) M. Maes et al. Environ. Microbiol. 11:1453, 2009. (4) Y. Sakamoto et al. Plant Pathol. 48:613, 1999.

Fetuses with ventriculomegaly diagnosed in the second trimester of pregnancy by in utero MR imaging: what happens in the third trimester?

BACKGROUND AND PURPOSE

Although MR imaging of the fetal brain has been shown to provide additional diagnostic information, the optimal timing of the study and the value of repeat studies remain unclear. The primary purpose of this study was to look for structural abnormalities of the fetal brain shown at 30-32 weeks' gestational age but not on the 20-24 weeks' study in fetuses originally referred with isolated VM. In particular, we wished to study the hypothesis that third-trimester fetal MR imaging studies would not show extra brain abnormalities compared with the second-trimester studies in this group.

MATERIALS AND METHODS

Ninety-nine women were admitted for a fetal MR study between 20-24 weeks' gestational age, and 46 of these women agreed to return for a second MR imaging examination at 30-32 weeks' gestational age. The other women were either lost to follow-up or declined the invitation to return. Two experienced observers measured the width of the trigones, and the results were compared, to test reliability. Changes in the degree of VM are reported along with changes in the diagnosis of structural brain abnormalities.

RESULTS

There was excellent reproducibility of trigone measurements between the 2 observers, with a mean absolute difference of <1 mm in the 40 fetuses that were ultimately shown to have isolated VM. Twenty-eight of 40 fetuses studied had mild VM on the first iuMR imaging examination, but in just more than half, the category of VM changed between the studies (5 had become normal-sized, 7 had progressed to moderate, 3 had become severe, and 13 remained mild). In 1 case, hypogenesis of the corpus callosum was recognized at 30-32 weeks but had not been reported on the 20-24 weeks' examination; the other 5 fetuses had brain pathology recognized on both fetal MR studies.

CONCLUSIONS

Trigone measurements can be made in a highly repeatable fashion on iuMR imaging. We have not shown any major advantage in repeating iuMR imaging at 30-32 weeks' gestation in terms of improved diagnosis of other structural brain abnormalities. With the converse of that argument, however, our data suggest that there is no advantage in delaying iuMR imaging studies to 30-32 weeks in the hope of improving detection rates.

A prospective study of fetuses with isolated ventriculomegaly investigated by antenatal sonography and in utero MR imaging

BACKGROUND AND PURPOSE

Fetal ventriculomegaly (VM) is important because of its high prevalence and high risk of association with other brain abnormalities. The purpose of this article was to investigate the hypotheses that including in utero MR imaging (iuMR) in the diagnostic pathway for fetuses with isolated VM on antenatal imaging will show other brain abnormalities in a high proportion of cases and that these will have a significant effect on clinical management.

MATERIALS AND METHODS

One hundred forty-seven pregnant women were recruited prospectively from 8 fetomaternal centers in Britain. All of the fetuses had VM diagnosed on sonography but no other abnormality. iuMR was performed, and the results of the examinations were compared with those of sonography. Two fetomaternal experts made independent assessments of the effects of any new diagnoses on clinical management.

RESULTS

Categoric assessments of ventricular size were the same in approximately 90% of fetuses. Other abnormalities were shown in 17% of fetuses. The most frequent additional brain abnormality shown on iuMR was agenesis of the corpus callosum. Severe VM was associated with an approximately 10-fold increase in the risk of another brain abnormality being present when compared with fetuses with mild VM. The most profound effects on clinical management, however, were found in cases of mild VM.

CONCLUSIONS

This work supports our hypotheses by showing a high detection rate of other brain pathology when iuMR was used to supplement antenatal sonography (17%). In a high proportion of cases, the detection of the extra pathology would have led to significant changes in clinical management.

Co- and counter-current spontaneous imbibition into groups of capillary tubes with lateral connections permitting cross-flow

A model for co- and counter-current imbibition through independent capillaries has already been developed and experiments conducted to verify the theory [E. Unsal, G. Mason, N.R. Morrow, D.W. Ruth, J. Colloid Interface Sci. 306 (2007) 105]. In this paper, the work is extended to capillaries which are connected laterally and in which cross-flow can take place. The fundamental pore geometry is a rod in an angled round-bottomed slot with a gap between the rod and a capping glass plate. The surfaces of the slot, rod and plate form capillaries and interconnecting passages which have non-axisymmetric cross-sections. Depending on the gap size either (i) a large single meniscus, (ii) two menisci one on each side of the rod, or (iii) three menisci, one between the rod and the glass additional to the ones on each side can be formed. A viscous refined oil was applied to one end of the capillaries and co-current and counter-current spontaneous imbibition experiments were performed. The opposite end was left open to the atmosphere for co-current experiments. When the gap between the rod and the plate was large, the imbibing oil advanced into the tubes with the meniscus in the largest capillary always lagging behind the two menisci in the other two smaller capillaries. For counter-current imbibition experiments the open end was sealed and connected to a sensitive pressure transducer. In some experiments, the oil imbibed into the smaller capillaries and expelled air as a series of bubbles from the end of the largest capillary. In other experiments, the oil was allowed to imbibe part way into the tubes before counter-current imbibition was started. The meniscus curvatures of the capillaries have been calculated using the Mayer and Stowe-Princen method for different cell slot angles and gap sizes using a value of zero for the contact angle. These values have been compared with actual values by measuring the capillary rise in the tubes; agreement was very close. A model for co-current and counter-current imbibition has also been developed. The significance of this model is that some hydraulic/capillary properties are common for both co-current and counter-current imbibition. The experiments give an illustration of behavior expected in a real porous material and verify the importance of the 'perfect cross-flow' modification to the 'bundle of parallel tubes' model.

A randomised trial of two methods of issuing prenatal test results: the ARIA (Amniocentesis Results: Investigation of Anxiety) trial

BACKGROUND

Many pregnant women experience anxiety while waiting for the results of diagnostic tests. Policies and practices intended to reduce this anxiety require evaluation.

OBJECTIVES

To test the following two hypotheses: * That giving amniocentesis results out on a fixed date alters maternal anxiety during the waiting period, compared with a policy of telling parents that the result will be issued "when available" (i.e. variable date). * That issuing early results from a rapid molecular test alters maternal anxiety during the waiting period, compared with not receiving any results prior to the karyotype. The effects of the two interventions on anxiety 1 month after receiving karyotype results were also examined.

DESIGN

A multicentre, randomised, controlled, open fixed sample, 2 x 2 factorial design trial, with equal randomisation.

SETTING

The prenatal diagnosis clinics in 12 hospitals in England offering amniocentesis as a diagnostic test for Down's syndrome.

SAMPLE

Two hundred and twenty-six women who had had an amniocentesis were randomised between June 2002 and July 2004. Eight women with abnormal results or test failure were excluded post-randomisation.

INTERVENTIONS

Issuing karyotype results on a prespecified fixed date, rather than issuing them as soon as they became available. Issuing karyotype results alone, or subsequent to issuing results from a rapid molecular test for the most common chromosomal abnormalities.

MAIN OUTCOME MEASURES

Average anxiety during the waiting period, calculated using daily scores from the short version of the Spielberger State-Trait Anxiety Inventory (STAI). Anxiety 1 month after receiving karyotype results, measured using the short form STAI.

RESULTS

Issuing early results from a partial but rapid test reduced maternal anxiety by a clinically significant amount during the waiting period (mean daily score 12.5 versus 14.8; scale score difference -2.36, 95% CI -1.2, -3.6), compared with receiving only the full karyotype results. There was no evidence that giving out karyotype results on a fixed or on a variable date altered maternal anxiety during the waiting period (mean daily score 13.2 versus 14.2; scale score difference -1.02, 95% CI -2.2, 0.2). One month after receiving normal karyotype results, anxiety was low in all groups, but women who had been given rapid test results tended to be more anxious than those who had not (mean single day score 9.2 versus 8.3; mean scale score difference 0.95, 95% CI -0.03, 1.9). This small to moderate effect did not reach conventional levels of statistical significance.

CONCLUSIONS

Rapid testing was a beneficial addition to karyotyping, at least in the short term. This does not necessarily imply that early results would be preferred to comprehensive ones if women had to choose between them. Because there are no clear advantages in anxiety terms of issuing karyotype results as soon as they become available, or on a fixed date, women could be given a choice between them.

Amniocentesis results: investigation of anxiety. The ARIA trial

OBJECTIVES

The Amniocentesis Results: Investigation of Anxiety (ARIA) trial tested two hypotheses: first, that giving amniocentesis results out on a fixed date alters maternal anxiety during the waiting period, compared with a policy of telling parents that the result will be issued 'when available' (i.e. a variable date), and secondly, that issuing early results from a rapid molecular test alters maternal anxiety during the waiting period, compared with not receiving any results prior to the karyotype. The effects of the two interventions on anxiety 1 month after receiving karyotype results were also examined.

DESIGN

A multi-centre, randomised, controlled, open fixed sample, 2 x 2 factorial design trial, with equal randomisation.

SETTING

Twelve hospitals in England offering amniocentesis as a diagnostic test for Down's syndrome.

PARTICIPANTS

A total of 226 women who had had an amniocentesis were randomised between June 2002 and July 2004. Eight women with abnormal results or test failure were excluded post-randomisation.

INTERVENTIONS

Issuing karyotype results on a prespecified fixed date, rather than issuing them as soon as they became available and issuing karyotype results alone, or subsequent to issuing results from a rapid molecular test for the most common chromosomal abnormalities.

MAIN OUTCOME MEASURES

Average anxiety during the waiting period, calculated using daily scores from the short version of the Spielberger State-Trait Anxiety Inventory (STAI). Recalled anxiety, measured 1 month after receiving karyotype results, using a rating scale. Anxiety at the 1-month follow-up, measured using the short-form STAI.

RESULTS

There was no evidence that giving out karyotype results on a fixed or on a variable date altered maternal anxiety during the waiting period. However, the analysis only had sufficient power to detect a moderate to large effect. Issuing early results from a partial, but rapid, test reduced maternal anxiety during the waiting period, compared with receiving only the full karyotype results. This was a moderate to large effect. In addition, group differences in recalled anxiety reflected fairly closely the differences in anxiety women had experienced while waiting for results. One month after receiving normal karyotype results, anxiety was low in all groups, but women who had been given rapid test results were more anxious than those who had not. This was a small to moderate effect.

CONCLUSIONS

Since there are no clear advantages in anxiety terms of issuing karyotype results as soon as they become available, or on a fixed date, women could be given a choice between them. Rapid testing was a beneficial addition to karyotyping, at least in the short term. This does not necessarily imply that early results would be preferred to comprehensive ones if women had to choose between them. There should be further research, including more qualitative studies, into the causes, characteristics and consequences of anxiety associated with prenatal testing. The effects of different testing regimes on short- and long-term anxiety, on the preferences of women and on the relationship between anxiety and preference should be investigated. More research is needed on the ways in which information might be used to minimise anxiety in different testing regimes. Further research is also required into the policy implications of incorporating individual preferences for different testing regimes into prenatal testing programmes.