Browsing by Author "Camargo Jr., Carlos A."

Now showing 1 - 5 of 5
  • Thumbnail Image
    Item
    Association between obesity and atopic dermatitis in children: A case-control study in a high obesity prevalence population
    (2022) Iturriaga, Carolina; Bustos, María Francisca; Le Roy, Catalina; Rodríguez, Rocío; Cifuentes, Lorena; Silva-Valenzuela, Sergio; Vera-Kellet, Cristián; Cristi, Francisca; Pérez-Mateluna, Guillermo; Cabalín, Carolina; Hoyos-Bachiloglu, Rodrigo; Camargo Jr., Carlos A.; Borzutzky Schachter, Arturo
    Background/Objective: Atopic dermatitis (AD) is a chronic inflammatory skin disease. Research suggests an association between obesity and AD, although evidence is lacking from Latin American populations. This study evaluated the association of obesity with AD in children from Chile, a country with high obesity prevalence. Methods: A case-control study was performed in children with active AD (cases) and healthy controls (HCs) from Santiago, Chile. Body mass index was evaluated by z-score (z-BMI), with overweight defined as z-BMI ≥+1 and <+2, and obesity as z-BMI ≥+2. Abdominal obesity was defined by a waist circumference-to-height ratio (WHR) ≥0.5. AD severity was evaluated by Scoring AD (SCORAD) index. Results: A total of 174 children with AD and 101 controls were included. AD patients had similar overweight (27% vs. 28%) and obesity (21% vs. 26%) rates as HCs (p = .65). Abdominal obesity rates were also comparable (64% vs. 62%, p = .81). In sex-specific analyses, girls with AD had higher abdominal obesity rates than HCs (71% vs. 53%, p < .05) while boys with AD had lower abdominal obesity rates than HCs (53% vs. 75%, p = .03). Among children with AD, higher z-BMI or WHR did not correlate with higher SCORAD, eosinophil counts or total IgE. Conclusion: In our study, Chilean children with AD had high but similar rates of obesity as HCs, but showed sex-specific associations of abdominal obesity and AD. Further research is needed to evaluate these associations and the roles that weight excess and weight loss could play in the pathogenesis and treatment of AD.
  • Thumbnail Image
    Item
    Oral vitamin D modulates the epidermal expression of the vitamin D receptor and cathelicidin in children with atopic dermatitis
    (2022) Cabalín, Carolina; Pérez-Mateluna, Guillermo; Iturriaga, Carolina; Camargo Jr., Carlos A.; Borzutzky Schachter, Arturo
    Although vitamin D (VD) is known to have multiple effects on the skin and immunity, its effects on atopic dermatitis (AD) severity remain unclear. We investigated whether oral cholecalciferol (VD3) supplementation changes stratum corneum expression of the vitamin D receptor (vdr), and the epidermal alarmins Cathelicidin Antimicrobial Peptide (camp/LL-37) and Thymic Stromal Lymphopoietin (tslp) in children with AD. We conducted an open-label supplementation study with weekly oral VD3 for six weeks in children with AD. Serum 25-hydroxyvitamin D (25OHD), lesional Staphylococcus aureus colonization, and AD severity evaluated by SCORAD index were evaluated before and after supplementation. Tape stripping (TS) was performed on non-lesional and lesional skin to measure mRNA expression of vdr, camp, and tslp through RT-qPCR and LL-37 peptide by ELISA. Twenty-two children with moderate–severe AD received weekly oral VD3 for six weeks. Total serum 25OHD increased from 45.1 ± 23 to 93.5 ± 24.3 nmoL/L (p < 0.0001), while SCORAD decreased from 41.4 ± 13.5 to 31.5 ± 15.8 (p < 0.0001). After treatment, epidermal gene expression of camp increased significantly in non-lesional (p = 0.014) and lesional (p = 0.0007) tape stripping samples, while vdr only increased in lesional skin samples (p < 0.0001). LL-37 peptide increased significantly only in lesional skin samples (p = 0.008). Gene expression of tslp did not change after oral VD3 treatment. In children with AD, oral VD3 supplementation was associated with improved VD status and AD severity, as well as increased VDR and Cathelicidin expression in lesional skin, which provide mechanistic clues on its effects.
  • Thumbnail Image
    Item
    Solar radiation is inversely associated with inflammatory bowel disease admissions
    (2017) Jaime Méndez, María Francisca; Riutort, Maria C.; Álvarez Lobos, Manuel; Hoyos Bachiloglu, Rodrigo Andrés; Camargo Jr., Carlos A.; Borzutzky Schachter, Arturo
  • Thumbnail Image
    Item
    Vitamin D deficiency rickets in an adolescent with severe atopic dermatitis
    (2014) Borzutzky Schachter, Arturo; Grob Lunecke, Francisca Andrea; Camargo Jr., Carlos A.; Martínez Aguayo, Alejandro Gregorio
  • Thumbnail Image
    Item
    Vitamin D supplementation to prevent acute respiratory infections: a systematic review and meta-analysis of aggregate data from randomised controlled trials
    (2021) Jolliffe, David A.; Camargo Jr., Carlos A.; Sluyter, John D.; Aglipay, Mary; Aloia, John F.; Ganmaa, Davaasambuu; Bergman, Peter; Bischoff-Ferrari, Heike A.; Borzutzky Schachter, Arturo; Damsgaard, Camilla T.; Dubnov-Raz, Gal; Esposito, Susanna; Gilham, Clare; Ginde, Adit A.; Golan-Tripto, Inbal; Goodall, Emma C.; Grant, Cameron C.; Griffiths, Christopher J.; Hibbs, Anna Maria; Janssens, Wim; Vaman Khadilkar, Anuradha; Laaksi, Ilkka; Lee, Margaret T.; Loeb, Mark; Maguire, Jonathon L.; Majak, Paweł; Mauger, David T.; Manaseki-Holland, Semira; Murdoch, David R.; Nakashima, Akio; Neale, Rachel E.; Pham, Hai; Rake, Christine; Rees, Judy R.; Rosendahl, Jenni; Scragg, Robert; Shah, Dheeraj; Shimizu, Yoshiki; Simpson-Yap, Steve; Trilok-Kumar, Geeta; Urashima, Mitsuyoshi; Martineau, Adrian R.
    Background: A 2017 meta-analysis of data from 25 randomised controlled trials (RCTs) of vitamin D supplementation for the prevention of acute respiratory infections (ARIs) revealed a protective effect of this intervention. We aimed to examine the link between vitamin D supplementation and prevention of ARIs in an updated meta-analysis. Methods: For this systematic review and meta-analysis, we searched MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, and the ClinicalTrials.gov registry for studies listed from database inception to May 1, 2020. Double-blind RCTs of vitamin D3, vitamin D2, or 25-hydroxyvitamin D (25[OH]D) supplementation for any duration, with a placebo or low-dose vitamin D control, were eligible if they had been approved by a research ethics committee, and if ARI incidence was collected prospectively and prespecified as an efficacy outcome. Studies reporting results of long-term follow-up of primary RCTs were excluded. Aggregated study-level data, stratified by baseline 25(OH)D concentration and age, were obtained from study authors. Using the proportion of participants in each trial who had one or more ARIs, we did a random-effects meta-analysis to obtain pooled odds ratios (ORs) and 95% CIs to estimate the effect of vitamin D supplementation on the risk of having one or more ARIs (primary outcome) compared with placebo. Subgroup analyses were done to estimate whether the effects of vitamin D supplementation on the risk of ARI varied according to baseline 25(OH)D concentration (<25 nmol/L vs 25·0–49·9 nmol/L vs 50·0–74·9 nmol/L vs >75·0 nmol/L), vitamin D dose (daily equivalent of <400 international units [IU] vs 400–1000 IU vs 1001–2000 IU vs >2000 IU), dosing frequency (daily vs weekly vs once per month to once every 3 months), trial duration (≤12 months vs >12 months), age at enrolment (<1·00 years vs 1·00–15·99 years vs 16·00–64·99 years vs ≥65·00 years), and presence versus absence of airway disease (ie, asthma only, COPD only, or unrestricted). Risk of bias was assessed with the Cochrane Collaboration Risk of Bias Tool. The study was registered with PROSPERO, CRD42020190633. Findings: We identified 1528 articles, of which 46 RCTs (75 541 participants) were eligible. Data for the primary outcome were obtained for 48 488 (98·1%) of 49 419 participants (aged 0–95 years) in 43 studies. A significantly lower proportion of participants in the vitamin D supplementation group had one or more ARIs (14 332 [61·3%] of 23 364 participants) than in the placebo group (14 217 [62·3%] of 22 802 participants), with an OR of 0·92 (95% CI 0·86–0·99; 37 studies; I2=35·6%, pheterogeneity=0·018). No significant effect of vitamin D supplementation on the risk of having one or more ARIs was observed for any of the subgroups defined by baseline 25(OH)D concentration. However, protective effects of supplementation were observed in trials in which vitamin D was given in a daily dosing regimen (OR 0·78 [95% CI 0·65–0·94]; 19 studies; I2=53·5%, pheterogeneity=0·003), at daily dose equivalents of 400–1000 IU (0·70 [0·55–0·89]; ten studies; I2=31·2%, pheterogeneity=0·16), for a duration of 12 months or less (0·82 [0·72–0·93]; 29 studies; I2=38·1%, pheterogeneity=0·021), and to participants aged 1·00–15·99 years at enrolment (0·71 [0·57–0·90]; 15 studies; I2=46·0%, pheterogeneity=0·027). No significant interaction between allocation to the vitamin D supplementation group versus the placebo group and dose, dose frequency, study duration, or age was observed. In addition, no significant difference in the proportion of participants who had at least one serious adverse event in the vitamin supplementation group compared with the placebo group was observed (0·97 [0·86–1·07]; 36 studies; I2=0·0%, pheterogeneity=0·99). Risk of bias within individual studies was assessed as being low for all but three trials. Interpretation: Despite evidence of significant heterogeneity across trials, vitamin D supplementation was safe and overall reduced the risk of ARI compared with placebo, although the risk reduction was small. Protection was associated with administration of daily doses of 400–1000 IU for up to 12 months, and age at enrolment of 1·00–15·99 years. The relevance of these findings to COVID-19 is not known and requires further investigation.