Nitisinone arrests ochronosis and decreases rate of progression of Alkaptonuria: Evaluation of the effect of nitisinone in the United Kingdom National Alkaptonuria Centre

QUESTION

Does Nitisinone prevent the clinical progression of the Alkaptonuria?

FINDINGS

In this observational study on 39 patients, 2 mg of daily nitisinone inhibited ochronosis and significantly slowed the progression of AKU over a three-year period.

MEANING

Nitisinone is a beneficial therapy in Alkaptonuria.

BACKGROUND

Nitisinone decreases homogentisic acid (HGA), but has not been shown to modify progression of Alkaptonuria (AKU).

METHODS

Thirty-nine AKU patients attended the National AKU Centre (NAC) in Liverpool for assessments and treatment. Nitisinone was commenced at V1 or baseline. Thirty nine, 34 and 22 AKU patients completed 1, 2 and 3 years of monitoring respectively (V2, V3 and V4) in the VAR group. Seventeen patients also attended a pre-baseline visit (V0) in the VAR group. Within the 39 patients, a subgroup of the same ten patients attended V0, V1, V2, V3 and V4 visits constituting the SAME Group. Severity of AKU was assessed by calculation of the AKU Severity Score Index (AKUSSI) allowing comparison between the pre-nitisinone and the nitisinone treatment phases.

RESULTS

The ALL (sum of clinical, joint and spine AKUSSI features) AKUSSI rate of change of scores/patient/month, in the SAME group, was significantly lower at two (0.32 ± 0.19) and three (0.15 ± 0.13) years post-nitisinone when compared to pre-nitisinone (0.65 ± 0.15) (p < .01 for both comparisons). Similarly, the ALL AKUSSI rate of change of scores/patient/month, in the VAR group, was significantly lower at one (0.16 ± 0.08) and three (0.19 ± 0.06) years post-nitisinone when compared to pre-nitisinone (0.59 ± 0.13) (p < .01 for both comparisons). Combined ear and ocular ochronosis rate of change of scores/patient/month was significantly lower at one, two and three year's post-nitisinone in both VAR and SAME groups compared with pre-nitisinone (p < .05).

CONCLUSION

This is the first indication that a 2 mg dose of nitisinone slows down the clinical progression of AKU. Combined ocular and ear ochronosis progression was arrested by nitisinone.

Applied Machine Learning for the Prediction of Growth of Abdominal Aortic Aneurysm in Humans

Objective

Accurate prediction of abdominal aortic aneurysm (AAA) growth in an individual can allow personalised stratification of surveillance intervals and better inform the timing for surgery. The authors recently described the novel significant association between flow mediated dilatation (FMD) and future AAA growth. The feasibility of predicting future AAA growth was explored in individual patients using a set of benchmark machine learning techniques.

Methods

The Oxford Abdominal Aortic Aneurysm Study (OxAAA) prospectively recruited AAA patients undergoing the routine NHS management pathway. In addition to the AAA diameter, FMD was systemically measured in these patients. A benchmark machine learning technique (non-linear Kernel support vector regression) was applied to predict future AAA growth in individual patients, using their baseline FMD and AAA diameter as input variables.

Results

Prospective growth data were recorded at 12 months (360 ± 49 days) in 94 patients. Of these, growth data were further recorded at 24 months (718 ± 81 days) in 79 patients. The average growth in AAA diameter was 3.4% at 12 months, and 2.8% per year at 24 months. The algorithm predicted the individual's AAA diameter to within 2 mm error in 85% and 71% of patients at 12 and 24 months.

Conclusions

The data highlight the utility of FMD as a biomarker for AAA and the value of machine learning techniques for AAA research in the new era of precision medicine.

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Flow mediated dilatation of brachial artery is a biomarker of AAA progression.

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It is feasible to predict future AAA growth in individuals using machine learning techniques.

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Endothelial dysfunction is a key feature in human AAA disease.

The impact of neighbourhood walkability on the effectiveness of a structured education programme to increase objectively measured walking

Background

Incorporating physical activity into daily activities is key for the effectiveness of lifestyle education interventions aimed at improving health outcomes; however, consideration of the environmental context in which individuals live is not always made. Walkability is a characteristic of the physical environment, and may be a potential facilitator to changing physical activity levels.

Methods

Using data collected during the Walking Away from Diabetes randomized controlled trial, we examined the association between the walkability of the home neighbourhood and physical activity of participants. We also determined whether home neighbourhood walkability of participants was associated with the intervention effect of the education programme.

Results

Data from 706 participants were available for analysis. Neighbourhood walkability was not significantly associated with any of the physical activity measures at baseline, or at 12, 24 or 36 months following the intervention (P > 0.05 for all). There was no association between walkability and change in purposeful steps/day from baseline to 36 months in the usual care or intervention arm; 25.77 (-99.04, 150.58) and 42.97 (-327.63, 413.45), respectively.

Conclusion

Neighbourhood walkability appeared to have no association with objectively measured physical activity in this population. Furthermore, the walkability of participant's neighbourhood did not influence the effectiveness of a lifestyle programme.

Adiposity and Cortisol Response to Stress in Indian Adolescents

OBJECTIVE

We examined associations of different adiposity measures with cortisol responses during the Trier Social Stress Test for children (TSST-C).

DESIGN

Descriptive study.

SETTING

Holdsworth Memorial Hospital, Mysore, India.

PARTICIPANTS

Adolescents aged 13.5y from a birth cohort were recruited (N=269, 133 boys).

METHODS

The stressor (TSST-C) was 5-minutes each of public speaking and mental arithmetic tasks in front of two unfamiliar 'judges'. Salivary cortisol concentrations were measured at baseline and at regular intervals after TSST-C. Weight, height, sub scapular and triceps skinfold thickness, and waist and hip circumference were measured, and percentage body fat was estimated (fat%; bioimpedance). Body mass index (BMI) and Waist-to-hip ratio (WHR) were calculated. All variables were converted into within-cohort SD scores before analysis. Stress-induced change in cortisol concentrations from baseline (cortisol response) was examined in relation to adiposity.

RESULTS

Stress increased cortisol concentrations significantly from baseline (mean (SD): 5.5 (6.4) ng/mL; P<0.001). Higher WHR was associated with lower cortisol response at 20 and 30-minutes after stress (~0.13 SD decrease in cortisol response per SD higher WHR, P<0.05). Higher fat% was also associated with lower cortisol response only in girls 20-minutes post-stress (0.23 SD lower response per SD higher fat%, P=0.004). Sum of skinfold thickness and BMI were not associated with cortisol responses.

CONCLUSION

Abdominal adiposity is associated with reduced hypothalamic-pituitary-adrenal axis reactivity to stress in this adolescent population.

Semantic fluency in deaf children who use spoken and signed language in comparison with hearing peers

BACKGROUND

Deafness has an adverse impact on children's ability to acquire spoken languages. Signed languages offer a more accessible input for deaf children, but because the vast majority are born to hearing parents who do not sign, their early exposure to sign language is limited. Deaf children as a whole are therefore at high risk of language delays.

AIMS

We compared deaf and hearing children's performance on a semantic fluency task. Optimal performance on this task requires a systematic search of the mental lexicon, the retrieval of words within a subcategory and, when that subcategory is exhausted, switching to a new subcategory. We compared retrieval patterns between groups, and also compared the responses of deaf children who used British Sign Language (BSL) with those who used spoken English. We investigated how semantic fluency performance related to children's expressive vocabulary and executive function skills, and also retested semantic fluency in the majority of the children nearly 2 years later, in order to investigate how much progress they had made in that time.

METHODS & PROCEDURES

Participants were deaf children aged 6-11 years (N = 106, comprising 69 users of spoken English, 29 users of BSL and eight users of Sign Supported English-SSE) compared with hearing children (N = 120) of the same age who used spoken English. Semantic fluency was tested for the category 'animals'. We coded for errors, clusters (e.g., 'pets', 'farm animals') and switches. Participants also completed the Expressive One-Word Picture Vocabulary Test and a battery of six non-verbal executive function tasks. In addition, we collected follow-up semantic fluency data for 70 deaf and 74 hearing children, nearly 2 years after they were first tested.

OUTCOMES & RESULTS

Deaf children, whether using spoken or signed language, produced fewer items in the semantic fluency task than hearing children, but they showed similar patterns of responses for items most commonly produced, clustering of items into subcategories and switching between subcategories. Both vocabulary and executive function scores predicted the number of correct items produced. Follow-up data from deaf participants showed continuing delays relative to hearing children 2 years later.

CONCLUSIONS & IMPLICATIONS

We conclude that semantic fluency can be used experimentally to investigate lexical organization in deaf children, and that it potentially has clinical utility across the heterogeneous deaf population. We present normative data to aid clinicians who wish to use this task with deaf children.

Peri-operative chest physiotherapy for paediatric cardiac patients: a systematic review and meta-analysis

BACKGROUND

Chest physiotherapy (CPT) is implemented before and after congenital heart disease (CHD) surgery in paediatrics to prevent and treat postoperative pulmonary complications (PPC). Currently, there are no systematic reviews or meta-analyses on the efficacy of CPT in this population.

OBJECTIVE

To conduct a systematic review and meta-analysis to determine whether peri-operative CPT is safe and effective for paediatric patients with CHD.

DATA SOURCES

A literature search was conducted on PEDro, MEDLINE, CINAHL, Informit, The Cochrane Library and Scopus in March and April 2016.

ELIGIBILITY CRITERIA

English peer-reviewed articles that utilised CPT before or after cardiac surgery for paediatric CHD. Systematic reviews were excluded.

DATA EXTRACTION AND SYNTHESIS

Completed by two independent researchers using the Crowe Critical Appraisal Tool. Data were collated using a piloted data extraction tool. Mix Version 2.0.1.4 was used for meta-analysis, and data were extracted using an odds ratio (with a random effects model).

RESULTS

Eleven studies met the inclusion criteria for the systematic review. Variable results were found regarding the effect of CPT on peripheral oxygen saturation and pain. Meta-analysis showed that CPT did not prevent pneumonia (odds ratio (OR) 2.01; 95% confidence interval (CI) 0.80 to 5.05; P=0.13), and did not prevent or treat atelectasis (OR 1.27; 95% CI 0.18 to 8.87; P=0.81).

LIMITATIONS

There was a lack of high-quality studies. The included studies were comprised of heterogeneous treatment, limiting external validity.

CONCLUSION

Active therapies such as mobilisation, deep breathing and incentive spirometry were more effective than passive treatment. Percussion led to oxygen desaturation, and percussion, vibration and suctioning increased the risk of developing atelectasis. Systematic review registration number CRD42015024768.

Initial validation of a virtual blood draw exposure paradigm for fear of blood and needles

Fear of blood, injections, and needles commonly prevents or delays individuals' receipt of health care, such as vaccines or blood draws. Innovative methods are needed to overcome these fears and reduce anxiety related to activities of this nature. The present study describes initial testing of an arm illusion paradigm that may prove useful during early phases of graded exposure for people with blood and needle fear. Seventy-four undergraduate students aged 18-29 years were tested. In line with study aims, results indicated that the virtual blood draw paradigm promoted strong perceptions of arm ownership and elicited significant changes in physiological indices (blood pressure, heart rate, electrodermal activity, respiratory rate) in response to key procedure elements (e.g., needle insertion). Further, bivariate correlations indicated that individual differences in self-reported blood and needle fear collected prior to the illusion paradigm were significantly associated with presyncopal symptoms reported following the procedure. In regression analyses, self-reported measures of blood and needle fear explained unique variance in presyncopal symptoms even after controlling for general state anxiety. These findings provide initial support for the virtual blood draw paradigm as a promising tool to help provide graded exposure to medical procedures involving needles and blood draw.

Screening protocols to monitor respiratory status in primary immunodeficiency disease: findings from a European survey and subclinical infection working group

Many patients with primary immunodeficiency (PID) who have antibody deficiency develop progressive lung disease due to underlying subclinical infection and inflammation. To understand how these patients are monitored we conducted a retrospective survey based on patient records of 13 PID centres across Europe, regarding the care of 1061 adult and 178 paediatric patients with PID on immunoglobulin (Ig) G replacement. The most common diagnosis was common variable immunodeficiency in adults (75%) and hypogammaglobulinaemia in children (39%). The frequency of clinic visits varied both within and between centres: every 1-12 months for adult patients and every 3-6 months for paediatric patients. Patients diagnosed with lung diseases were more likely to receive pharmaceutical therapies and received a wider range of therapies than patients without lung disease. Variation existed between centres in the frequency with which some clinical and laboratory monitoring tests are performed, including exercise tests, laboratory testing for IgG subclass levels and specific antibodies, and lung function tests such as spirometry. Some tests were carried out more frequently in adults than in children, probably due to difficulties conducting these tests in younger children. The percentage of patients seen regularly by a chest physician, or who had microbiology tests performed following chest and sinus exacerbations, also varied widely between centres. Our survey revealed a great deal of variation across Europe in how frequently patients with PID visit the clinic and how frequently some monitoring tests are carried out. These results highlight the urgent need for consensus guidelines on how to monitor lung complications in PID patients.

Temporal dissociation of salience and prediction error responses to appetitive and aversive taste

The feedback-related negativity (FRN), a frontocentral ERP occurring 200-350 ms after emotionally valued outcomes, has been posited as the neural correlate of reward prediction error, a key component of associative learning. Recent evidence challenged this interpretation and has led to the suggestion that this ERP expresses salience instead. Here, we distinguish between utility prediction error and salience by delivering or withholding hedonistically matched appetitive and aversive tastes, and measure ERPs to cues signaling each taste. We observed a typical FRN (computed as the loss-minus-gain difference wave) to appetitive taste, but a reverse FRN to aversive taste. When tested axiomatically, frontocentral ERPs showed a salience response across tastes, with a particularly early response to outcome delivery, supporting recent propositions of a fast, unsigned, and unspecific response to salient stimuli. ERPs also expressed aversive prediction error peaking at 285 ms, which conformed to the logic of an axiomatic model of prediction error. With stimuli that most resemble those used in animal models, we did not detect any frontocentral ERP signal for utility prediction error, in contrast with dominant views of the functional role of the FRN ERP. We link the animal and human literature and present a challenge for current perspectives on associative learning research using ERPs.