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Dive into the research topics where Raj K. Rajakulasingam is active.

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Featured researches published by Raj K. Rajakulasingam.


The Lancet Respiratory Medicine | 2015

Vitamin D3 supplementation in patients with chronic obstructive pulmonary disease (ViDiCO): a multicentre, double-blind, randomised controlled trial

Adrian R. Martineau; Wai Yee James; Richard Hooper; Neil Barnes; David A. Jolliffe; Claire L Greiller; Kamrul Islam; David McLaughlin; Angshu Bhowmik; Peter Timms; Raj K. Rajakulasingam; Marion Rowe; Timothy R Venton; Aklak Choudhury; David E Simcock; Mark Wilks; Amarjeet Degun; Zia Sadique; William Monteiro; Christopher Corrigan; Catherine Hawrylowicz; Chris Griffiths

BACKGROUND Patients with chronic obstructive pulmonary disease (COPD) often have vitamin D deficiency, which is associated with increased susceptibility to upper respiratory infection-a major precipitant of exacerbation. Multicentre trials of vitamin D supplementation for prevention of exacerbation and upper respiratory infection in patients with COPD are lacking. We therefore investigated whether vitamin D3 (colecalciferol) supplementation would reduce the incidence of moderate or severe COPD exacerbations and upper respiratory infections. METHODS We did a randomised, double-blind, placebo-controlled trial of vitamin D3 supplementation in adults with COPD in 60 general practices and four Acute National Health Service Trust clinics in London, UK. Patients were allocated to receive six 2-monthly oral doses of 3 mg vitamin D3 or placebo over 1 year in a 1:1 ratio using computer-generated permuted block randomisation. Participants and study staff were masked to treatment assignment. Coprimary outcomes were time to first moderate or severe exacerbation and first upper respiratory infection. Analysis was by intention to treat. A prespecified subgroup analysis was done to assess whether effects of the intervention on the coprimary outcomes were modified by baseline vitamin D status. This trial is registered with ClinicalTrials.gov, number NCT00977873. FINDINGS 240 patients were randomly allocated to the vitamin D3 group (n=122) and placebo group (n=118). Vitamin D3 compared with placebo did not affect time to first moderate or severe exacerbation (adjusted hazard ratio 0·86, 95% CI 0·60-1·24, p=0·42) or time to first upper respiratory infection (0·95, 0·69-1·31, p=0·75). Prespecified subgroup analysis showed that vitamin D3 was protective against moderate or severe exacerbation in participants with baseline serum 25-hydroxyvitamin D concentrations of less than 50 nmol/L (0·57, 0·35-0·92, p=0·021), but not in those with baseline 25-hydroxyvitamin D levels of at least 50 nmol/L (1·45, 0·81-2·62, p=0·21; p=0·021 for interaction between allocation and baseline serum 25-hydroxyvitamin D status). Baseline vitamin D status did not modify the effect of the intervention on risk of upper respiratory infection (pinteraction=0·41). INTERPRETATION Vitamin D3 supplementation protected against moderate or severe exacerbation, but not upper respiratory infection, in patients with COPD with baseline 25-hydroxyvitamin D levels of less than 50 nmol/L. Our findings suggest that correction of vitamin D deficiency in patients with COPD reduces the risk of moderate or severe exacerbation. FUNDING UK National Institute for Health Research.


Thorax | 2015

Double-blind randomised placebo-controlled trial of bolus-dose vitamin D3 supplementation in adults with asthma (ViDiAs)

Adrian R. Martineau; Beverley MacLaughlin; Richard Hooper; Neil Barnes; David A. Jolliffe; Claire L Greiller; Kate Kilpin; David McLaughlin; Gareth Fletcher; Charles A. Mein; Mimoza Hoti; Robert Walton; Jonathan Grigg; Peter Timms; Raj K. Rajakulasingam; Angshu Bhowmik; Marion Rowe; Timothy R Venton; Aklak Choudhury; David E Simcock; Zia Sadique; William Monteiro; Christopher Corrigan; Catherine Hawrylowicz; Chris Griffiths

Rationale Asthma exacerbations are commonly precipitated by viral upper respiratory infections (URIs). Vitamin D insufficiency associates with susceptibility to URI in patients with asthma. Trials of vitamin D in adults with asthma with incidence of exacerbation and URI as primary outcome are lacking. Objective To conduct a randomised controlled trial of vitamin D3 supplementation for the prevention of asthma exacerbation and URI (coprimary outcomes). Measurements and methods 250 adults with asthma in London, UK were allocated to receive six 2-monthly oral doses of 3 mg vitamin D3 (n=125) or placebo (n=125) over 1 year. Secondary outcomes included asthma control test and St Georges Respiratory Questionnaire scores, fractional exhaled nitric oxide and concentrations of inflammatory markers in induced sputum. Subgroup analyses were performed to determine whether effects of supplementation were modified by baseline vitamin D status or genotype for 34 single nucleotide polymorphisms in 11 vitamin D pathway genes. Main results 206/250 participants (82%) were vitamin D insufficient at baseline. Vitamin D3 did not influence time to first severe exacerbation (adjusted HR 1.02, 95% CI 0.69 to 1.53, p=0.91) or first URI (adjusted HR 0.87, 95% CI 0.64 to 1.16, p=0.34). No clinically important effect of vitamin D3 was seen on any of the secondary outcomes listed above. The influence of vitamin D3 on coprimary outcomes was not modified by baseline vitamin D status or genotype. Conclusions Bolus-dose vitamin D3 supplementation did not influence time to exacerbation or URI in a population of adults with asthma with a high prevalence of baseline vitamin D insufficiency. Trial registration number NCT00978315 (ClinicalTrials.gov).


European Respiratory Journal | 2016

Omalizumab reduces bronchial mucosal IgE and improves lung function in non-atopic asthma.

Prathap Pillai; Yih-Chih Chan; Shih-Ying Wu; Line Ohm-Laursen; Clare Thomas; Stephen R. Durham; Andrew Menzies-Gow; Raj K. Rajakulasingam; Sun Ying; Hannah J. Gould; Christopher Corrigan

Omalizumab therapy of non-atopic asthmatics reduces bronchial mucosal IgE and inflammation and preserves/improves lung function when disease is destabilised by staged withdrawal of therapy. 18 symptomatic, non-atopic asthmatics were randomised (1:1) to receive omalizumab or identical placebo treatment in addition to existing therapy for 20 weeks. Bronchial biopsies were collected before and after 12–14 weeks of treatment, then the patients destabilised by substantial, supervised reduction of their regular therapy. Primary outcome measures were changes in bronchial mucosal IgE+ cells at 12–14 weeks, prior to regular therapy reduction, and changes in lung function (forced expiratory volume in 1 s) after destabilisation at 20 weeks. Quality of life was also monitored. Omalizumab but not placebo therapy significantly reduced median total bronchial mucosal IgE+ cells (p<0.01) but did not significantly alter median total mast cells, plasma cells, B lymphocytes, eosinophils and plasmablasts, although the latter were difficult to enumerate, being distributed as disperse clusters. By 20 weeks, lung function declined in the placebo-treated patients but improved in the omalizumab treated patients, with significant differences in absolute (p=0.04) and % predicted forced expiratory volume in 1 s (p=0.015). Omalizumab therapy of non-atopic asthmatics reduces bronchial mucosal IgE+ mast cells and improves lung function despite withdrawal of conventional therapy. Omalizumab reduces mucosal IgE and improves lung function in non-atopic asthma http://ow.ly/CHFu3034fcC


The Journal of Steroid Biochemistry and Molecular Biology | 2018

Prevalence, determinants and clinical correlates of vitamin D deficiency in adults with inhaled corticosteroid-treated asthma in London, UK

David A. Jolliffe; Kate Kilpin; Beverley MacLaughlin; Claire L Greiller; Richard Hooper; Neil Barnes; Peter Timms; Raj K. Rajakulasingam; Angshu Bhowmik; Aklak Choudhury; David E Simcock; Elina Hyppönen; Christopher Corrigan; Robert Walton; Chris Griffiths; Adrian R. Martineau

Vitamin D deficiency is common in children with asthma, and it associates with poor asthma control, reduced forced expiratory volume in one second (FEV1) and increased requirement for inhaled corticosteroids (ICS). Cross-sectional studies investigating the prevalence, determinants and clinical correlates of vitamin D deficiency in adults with asthma are lacking. We conducted a multi-centre cross-sectional study in 297 adults with a medical record diagnosis of ICS-treated asthma living in London, UK. Details of potential environmental determinants of vitamin D status, asthma control and medication use were collected by questionnaire; blood samples were taken for analysis of serum 25(OH)D concentration and DNA extraction, and participants underwent measurement of weight, height and fractional exhaled nitric oxide concentration (FeNO), spirometry and sputum induction for determination of lower airway eosinophil counts (n=35 sub-group). Thirty-five single nucleotide polymorphisms (SNP) in 11 vitamin D pathway genes (DBP, DHCR7, RXRA, CYP2R1, CYP27B1, CYP24A1, CYP3A4 CYP27A1, LRP2, CUBN, VDR) were typed using Taqman allelic discrimination assays. Linear regression was used to identify environmental and genetic factors independently associated with serum 25(OH)D concentration, and to determine whether vitamin D status was independently associated with Asthma Control Test (ACT) score, ICS dose, FeNO, forced vital capacity (FVC), FEV1 or lower airway eosinophilia. Mean serum 25(OH)D concentration was 50.6nmol/L (SD 24.9); 162/297 (54.5%) participants were vitamin D deficient (serum 25(OH)D concentration <50nmol/L). Lower vitamin D status was associated with higher body mass index (P=0.014), non-White ethnicity (P=0.036), unemployment (P for trend=0.012), lack of vitamin D supplement use (P<0.001), sampling in Winter or Spring (P for trend <0.001) and lack of a recent sunny holiday abroad (P=0.030), but not with potential genetic determinants. Vitamin D status was not found to associate with any marker of asthma control investigated. Vitamin D deficiency is common among UK adults with ICS-treated asthma, and classical environmental determinants of serum 25(OH)D operate in this population. However, in contrast to studies conducted in children, we found no association between vitamin D status and markers of asthma severity or control.


The Journal of Steroid Biochemistry and Molecular Biology | 2018

Prevalence, determinants and clinical correlates of vitamin D deficiency in patients with Chronic Obstructive Pulmonary Disease in London, UK

David A. Jolliffe; Wai Yee James; Richard Hooper; Neil Barnes; Claire L Greiller; Kamrul Islam; Angshu Bhowmik; Peter Timms; Raj K. Rajakulasingam; Aklak Choudhury; David E Simcock; Elina Hyppönen; Robert Walton; Christopher Corrigan; Chris Griffiths; Adrian R. Martineau

Vitamin D deficiency is common in patients with chronic obstructive pulmonary disease (COPD), yet a comprehensive analysis of environmental and genetic determinants of serum 25-hydroxyvitamin D (25[OH]D) concentration in patients with this condition is lacking. We conducted a multi-centre cross-sectional study in 278 COPD patients aged 41-92 years in London, UK. Details of potential environmental determinants of vitamin D status and COPD symptom control and severity were collected by questionnaire, and blood samples were taken for analysis of serum 25(OH)D concentration and DNA extraction. All participants performed spirometry and underwent measurement of weight and height. Quadriceps muscle strength (QS) was measured in 134 participants, and sputum induction with enumeration of lower airway eosinophil and neutrophil counts was performed for 44 participants. Thirty-seven single nucleotide polymorphisms (SNP) in 11 genes in the vitamin D pathway (DBP, DHCR7, CYP2R1, CYP27B1, CYP24A1, CYP27A1, CYP3A4, LRP2, CUBN, RXRA, and VDR) were typed using Taqman allelic discrimination assays. Linear regression was used to identify environmental and genetic factors independently associated with serum 25(OH)D concentration and to determine whether vitamin D status or genetic factors independently associated with % predicted forced expiratory volume in one second (FEV1), % predicted forced vital capacity (FVC), the ratio of FEV1 to FVC (FEV1:FVC), daily inhaled corticosteroid (ICS) dose, respiratory quality of life (QoL), QS, and the percentage of eosinophils and neutrophils in induced sputum. Mean serum 25(OH)D concentration was 45.4nmol/L (SD 25.3); 171/278 (61.5%) participants were vitamin D deficient (serum 25[OH]D concentration <50nmol/L). Lower vitamin D status was independently associated with higher body mass index (P=0.001), lower socio-economic position (P=0.037), lack of vitamin D supplement consumption (P<0.001), sampling in Winter or Spring (P for trend=0.006) and lack of a recent sunny holiday (P=0.002). Vitamin D deficiency associated with reduced % predicted FEV1 (P for trend=0.060) and % predicted FVC (P for trend=0.003), but it did not associate with FEV1:FVC, ICS dose, QoL, QS, or the percentage of eosinophils or neutrophils in induced sputum. After correction for multiple comparisons testing, genetic variation in the vitamin D pathway was not found to associate with serum 25(OH)D concentration or clinical correlates of COPD severity. Vitamin D deficiency was common in this group of COPD patients in the UK, and it associated independently with reduced % predicted FEV1 and FVC. However, genetic variation in the vitamin D pathway was not associated with vitamin D status or severity of COPD.


The Lancet | 2015

P2X3 receptor antagonist in chronic cough

Richard Turner; Raj K. Rajakulasingam; Angshu Bhowmik; Graham Bothamley

244 www.thelancet.com Vol 386 July 18, 2015 of an underlying cough trigger” such as “refl ux disease, asthma, and postnasal drip”. However, 25% of patients had a productive cough, and patients with a forced expiratory volume in 1 s to forced vital capacity ratio less than 70% (the accepted defi nition for COPD) were included. Thus, in figure 2 of the Article, it would be interesting to know the identity of patients with a productive cough, and a possible diagnosis of chronic bronchitis. P2X receptors appear to be key for taste sensation. This might have unmasked participants and aff ected their subjective assessment of the active drug. However, the gustatory effect might itself have been antitussive and counterbalanced such con founding. This study has raised important questions, which will be valuable in the search for treatments for chronic cough.


Case Reports | 2014

Recurrent lip swelling: a diagnostic challenge

Sonam Lakhani; Sheena Barnett; Anwar R. Tappuni; Raj K. Rajakulasingam

A Caucasian woman in her late 20s was referred to the allergy/chest clinic by her general practitioner with an 8-month history of recurrent facial angio-oedema. She had no history of urticaria or airways symptoms and denied any similar problems previously. She had no family history of similar illness and was not on any regular medications. There was no history of atopy. Initially, a clinical diagnosis of idiopathic angio-oedema was made. Despite being treated with several antihistamines with doses equivalent to 40 mg of cetirizine/day, her problem had failed to respond satisfactorily. Later on, she also revealed history of intermittent gastrointestinal symptoms such as abdominal pain and diarrhoea. Routine investigations were unremarkable. The patient was referred to a dermatology clinic and a diagnosis of orofacial granulomatosis was suggested: a rare granulomatous disease presenting with lip enlargement, which may or may not be associated with Crohns disease. A biopsy of the oral mucosa was consistent with this diagnosis.


The Journal of Allergy and Clinical Immunology | 2014

Allergen-specific IgE is not detectable in the bronchial mucosa of nonatopic asthmatic patients

Prathap Pillai; Cailong Fang; Yih-Chih Chan; Mohamed H. Shamji; Clare Harper; Shih-Ying Wu; Line Ohm-Laursen; Stephen R. Durham; Andrew Menzies-Gow; Raj K. Rajakulasingam; Sun Ying; Christopher Corrigan; Hannah J. Gould


The Lancet | 2003

Combined salmeterol and fluticasone for COPD

Ramzi Y Khamis; Raj K. Rajakulasingam


Thorax | 2014

S95 Double-blind Multi-centre Randomised Controlled Trial Of Vitamin D3 Supplementation In Adults With Inhaled Corticosteroid-treated Asthma (vidias)

Adrian R. Martineau; Beverley MacLaughlin; Richard Hooper; Neil Barnes; David A. Jolliffe; Aklak Choudhury; Raj K. Rajakulasingam; Angshu Bhowmik; David E Simcock; Jonathan Grigg; Christopher Corrigan; Catherine Hawrylowicz; Cj Griffiths

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Adrian R. Martineau

Queen Mary University of London

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David A. Jolliffe

Queen Mary University of London

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Neil Barnes

Queen Mary University of London

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Aklak Choudhury

The Queen's Medical Center

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Chris Griffiths

Queen Mary University of London

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Claire L Greiller

Queen Mary University of London

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Richard Hooper

Queen Mary University of London

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