Antibody responses to SARS-CoV-2 spike protein in a cohort of renal transplant recipients following two-dose primary immunization - A Caribbean country's perspective.

This study compares the humoral immune response of a cohort of renal transplant recipients (RTRs), in Trinidad & Tobago following two-dose primary immunization with non-mRNA vaccines amidst the COVID-19 pandemic. RTRs along with healthy, age-and gender-matched controls received either the adenoviral vector vaccine, AstraZeneca-Vaxzevria (AZ) or the inactivated vaccine, Beijing CNBG-BBIBP- CorV/Sinopharm (SP). Samples were taken after completion of a two-dose primary immunization during the period November 2021 to December 2021, at a mean interval of 138 days following immunization. 38/72 RTRs (53 %) failed to generate any protective antibody responses, compared with 7/73 participants, approximately 10 % in the healthy, age and gender-matched control group. In the RTRs, there was no significant correlation of their antibody concentration with either the timing of sample collection or the interval since transplantation. The study provides necessary information about the humoral response after two- doses of non-mRNA vaccines in a group of transplant recipients.

Overweight and Obesity in Children Are Associated with an Abundance of Firmicutes and Reduction of Bifidobacterium in Their Gastrointestinal Microbiota.

Background: Obesity in children continues to be a global epidemic. Given the recent focus on the potential role gut microbiota play in the development of obesity and the continuous rise of obesity in childhood worldwide, it has become necessary that the association between gut microbes and weight is explored in previously unexplored regions such as the Caribbean island of Trinidad. As such, our objective was to characterize the composition of the gut microbiota in children with obesity/overweight and children of normal weight to determine if there are any gut microbes associated with overweight and obesity. Methods: Fifty-one children provided stool samples and their BMIs were calculated and classified. 16S amplicons from stool samples were individually barcoded and sequenced in multiplex in the NextSeq 500 platform in a 150 bp paired-end modality and a complete gut microbiome profile was generated. Results: The relative abundance and diversity of the microbiota of the lean and children with obesity/overweight were analyzed against each other and showed that children with obesity/overweight recorded significantly more (p = 0.001) Firmicutes and significantly less Bifidobacterium (p = 0.039) than the children of normal weight. Children with obesity/overweight also recorded significantly (p = 0.009) reduced alpha diversity compared with the lean children. Conclusion: This study has shown associations of Firmicutes to obesity/overweight and Bifidobacterium species with healthy weight in children.

Atypical Chemokine Receptor 1 (DARC/ACKR1) in Breast Tumors Is Associated with Survival, Circulating Chemokines, Tumor-Infiltrating Immune Cells, and African Ancestry.

BACKGROUND: Tumor-specific immune response is an important aspect of disease prognosis and ultimately impacts treatment decisions for innovative immunotherapies. The atypical chemokine receptor 1 (ACKR1 or DARC) gene plays a pivotal role in immune regulation and harbors several single-nucleotide variants (SNV) that are specific to sub-Saharan African ancestry. METHODS: Using computational The Cancer Genome Atlas (TCGA) analysis, case-control clinical cohort Luminex assays, and CIBERSORT deconvolution, we identified distinct immune cell profile-associated DARC/ACKR1 tumor expression and race with increased macrophage subtypes and regulatory T cells in DARC/ACKR1-high tumors. RESULTS: In this study, we report the clinical relevance of DARC/ACKR1 tumor expression in breast cancer, in the context of a tumor immune response that may be associated with sub-Saharan African ancestry. Briefly, we found that for infiltrating carcinomas, African Americans have a higher proportion of DARC/ACKR1-negative tumors compared with white Americans, and DARC/ACKR1 tumor expression is correlated with proinflammatory chemokines, CCL2/MCP-1 (P <0.0001) and anticorrelated with CXCL8/IL8 (P <0.0001). Sub-Saharan African-specific DARC/ACKR1 alleles likely drive these correlations. Relapse-free survival (RFS) and overall survival (OS) were significantly longer in individuals with DARC/ACKR1-high tumors (P <1.0 × 10-16 and P <2.2 × 10-6, respectively) across all molecular tumor subtypes. CONCLUSIONS: DARC/AKCR1 regulates immune responses in tumors, and its expression is associated with sub-Saharan African-specific alleles. DARC/ACKR1-positive tumors will have a distinct immune response compared with DARC/AKCR1-negative tumors. IMPACT: This study has high relevance in cancer management, as we introduce a functional regulator of inflammatory chemokines that can determine an infiltrating tumor immune cell landscape that is distinct among patients of African ancestry.

Distinct Transcript Isoforms of the Atypical Chemokine Receptor 1 (ACKR1)/Duffy Antigen Receptor for Chemokines (DARC) Gene Are Expressed in Lymphoblasts and Altered Isoform Levels Are Associated with Genetic Ancestry and the Duffy-Null Allele.

The Atypical ChemoKine Receptor 1 (ACKR1) gene, better known as Duffy Antigen Receptor for Chemokines (DARC or Duffy), is responsible for the Duffy Blood Group and plays a major role in regulating the circulating homeostatic levels of pro-inflammatory chemokines. Previous studies have shown that one common variant, the Duffy Null (Fy-) allele that is specific to African Ancestry groups, completely removes expression of the gene on erythrocytes; however, these individuals retain endothelial expression. Additional alleles are associated with a myriad of clinical outcomes related to immune responses and inflammation. In addition to allele variants, there are two distinct transcript isoforms of DARC which are expressed from separate promoters, and very little is known about the distinct transcriptional regulation or the distinct functionality of these protein isoforms. Our objective was to determine if the African specific Fy- allele alters the expression pattern of DARC isoforms and therefore could potentially result in a unique signature of the gene products, commonly referred to as antigens. Our work is the first to establish that there is expression of DARC on lymphoblasts. Our data indicates that people of African ancestry have distinct relative levels of DARC isoforms expressed in these cells. We conclude that the expression of both isoforms in combination with alternate alleles yields multiple Duffy antigens in ancestry groups, depending upon the haplotypes across the gene. Importantly, we hypothesize that DARC isoform expression patterns will translate into ancestry-specific inflammatory responses that are correlated with the axis of pro-inflammatory chemokine levels and distinct isoform-specific interactions with these chemokines. Ultimately, this work will increase knowledge of biological mechanisms underlying disparate clinical outcomes of inflammatory-related diseases among ethnic and geographic ancestry groups.

Human papillomavirus genotypes and their prevalence in a cohort of women in Trinidad.

OBJECTIVE: Human papillomavirus (HPV) genotypes and their relative prevalences were determined in a cohort of 310 sexually active women in Trinidad, West Indies. METHODS: Cervical samples were collected with Ayre's spatulas and endocervical brushes. Samples were used for the conventional Papanicolaou test and for determining HPV genotypes by amplification of a section of the viral L1 gene, followed by DNA sequencing and probe hybridization. RESULTS: HPV infections were identified in 126 of 310 (40.6%) women. Of them, 83 (65.8%) were infected with high-risk HPV, 16 (12.7%) with low-risk HPV, and 27 (21.4%) with HPV types of unknown risk. HPV 52 (12.7%) was the most frequently occurring high-risk type, followed by HPV 66 (10.3%), HPV 16 (9.5%), and HPV 18 (8.6%). High-risk types HPV 16 and HPV 66 were each found in 3 (20.0%) and HPV 18 was found in 1 (6.6%) of the 15 women with abnormal cytology. CONCLUSIONS: Cervical HPV prevalence and heterogeneity of HPV genotypes are high in this Trinidad cohort. The relative importance of HPV genotypes in the development of cervical lesions needs further investigation in Trinidad in order to better understand the epidemiology of HPV infections as well as to determine the role of HPV testing in the screening, prevention, and control of cervical cancer. This pilot study provided important information on the prevalence of HPV genotypes, which will be used in future nationwide studies.

Human papillomavirus genotypes and their prevalence in a cohort of women in Trinidad / Genotipos del papilomavirus humano y su prevalencia en una cohorte de mujeres en Trinidad

OBJECTIVE: Human papillomavirus (HPV) genotypes and their relative prevalences were determined in a cohort of 310 sexually active women in Trinidad, West Indies. METHODS: Cervical samples were collected with Ayre's spatulas and endocervical brushes. Samples were used for the conventional Papanicolaou test and for determining HPV genotypes by amplification of a section of the viral L1 gene, followed by DNA sequencing and probe hybridization. RESULTS: HPV infections were identified in 126 of 310 (40.6 percent) women. Of them, 83 (65.8 percent) were infected with high-risk HPV, 16 (12.7 percent) with low-risk HPV, and 27 (21.4 percent) with HPV types of unknown risk. HPV 52 (12.7 percent) was the most frequently occurring high-risk type, followed by HPV 66 (10.3 percent), HPV 16 (9.5 percent), and HPV 18 (8.6 percent). High-risk types HPV 16 and HPV 66 were each found in 3 (20.0 percent) and HPV 18 was found in 1 (6.6 percent) of the 15 women with abnormal cytology. CONCLUSIONS: Cervical HPV prevalence and heterogeneity of HPV genotypes are high in this Trinidad cohort. The relative importance of HPV genotypes in the development of cervical lesions needs further investigation in Trinidad in order to better understand the epidemiology of HPV infections as well as to determine the role of HPV testing in the screening, prevention, and control of cervical cancer. This pilot study provided important information on the prevalence of HPV genotypes, which will be used in future nationwide studies.

OBJETIVO: Se determinaron los genotipos del papilomavirus humano (PVH) y su prevalencia relativa en una cohorte de 310 mujeres sexualmente activas de Trinidad, en la zona de las Indias Occidentales. MÉTODOS: Se tomaron muestras del cuello uterino con espátula de Ayre y cepillo endocervical. Las muestras se usaron para llevar a cabo la prueba convencional de Papanicolaou y para determinar los genotipos de PVH mediante la amplificación de una sección del gen vírico L1, seguida de secuenciación del ADN e hibridación con sonda. RESULTADOS: Se encontró una infección por PVH en 126 de las 310 mujeres (40,6 por ciento). De ellas, 83 (65,8 por ciento) estaban infectadas con PVH de alto riesgo, 16 (12,7 por ciento) con PVH de bajo riesgo, y 27 (21,4 por ciento) con tipos de PVH de riesgo desconocido. De los PVH de alto riesgo, el más frecuente fue el PVH 52 (12,7 por ciento), seguido por el PVH 66 (10,3 por ciento), el PVH 16 (9,5 por ciento) y el PVH 18 (8,6 por ciento). Entre las 15 mujeres con citología anormal se encontraron los PVH de alto riesgo 16 y 66 en 3 (20,0 por ciento) mujeres cada uno, y el PVH 18 en 1 (6,6 por ciento). CONCLUSIONES: Tanto la prevalencia de PVH en el cuello uterino como la heterogeneidad de los genotipos de PVH son elevadas en esta cohorte de Trinidad. La importancia relativa de los genotipos de PVH en la aparición de las lesiones cervicales requiere de mayor investigación en Trinidad para conocer más a fondo las características epidemiológicas de las infecciones por PVH, así como para determinar el papel del estudio de los PVH en la detección sistemática, la prevención y el control del cáncer del cuello uterino. Este estudio piloto suministró información importante sobre la prevalencia de los genotipos de PVH, que se usará en futuros estudios que se lleven a cabo en todo el país.

Effect of N-acetyl-L-cysteine on Cytokine Production by Human Peripheral Blood Mononuclear Cells.

OBJECTIVES: This study investigates the in vitro effect of the antioxidant drug, N-acetyl-L-cysteine (NAC), on cytokine production by peripheral blood mononuclear cells (PBMC). METHODS: PBMC were isolated by Ficoll-Hypaque, and stimulated with anti-CD3 antibodies, phytohaemagglutinin (PHA), lipopolysaccharide (LPS) for 24 hours in the presence or absence of 5 mM NAC. The cytokines produced were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Treatment with NAC significantly up-regulates the secretion of IL-1ß, IL-5 (interleukin) and IFN-γ (interferon) and down regulates IL-10 production, after anti-CD3 or PHA (p<0.05), but not after LPS stimulation. NAC also significantly increased total IL-12 secretion after anti-CD3 (but not PHA or LPS) stimulation and IL-12p40 after anti-CD3, PHA, and LPS stimulation (p <0.05). CONCLUSION: These results indicate that NAC up-regulated the production of pro-inflammatory cytokines, and down regulated anti-inflammatory cytokine production by PBMC, in a process which may be associated with increased levels of glutathione (GSH). Further work is required to determine whether this increase or decrease in cytokine production is due to direct effect of NAC.

Saharan dust clouds and human health in the English-speaking Caribbean: what we know and don't know.

Dust clouds travel across the Atlantic to the Americas and the Caribbean Islands. This long-range transport of dust leads to clouds that are enriched with small particles less than 10 microm aerodynamic diameter (PM10) which can reach human airways. The dust clouds also bring pollen, microbes, insects and chemicals, all of which could potentially have a negative impact on human health. This has led to a small number of retrospective studies being conducted on the islands of Barbados and Trinidad to look at possible associations between dust cover and acute asthma admissions to Emergency Rooms. The results have been conflicting. This review examines these studies, offers possible explanations for the differences in results, and suggests that there is a need for a prospective Caribbean-wide study to assess fully any relationship between African dust clouds and human respiratory and cardiovascular diseases.

Prevalence and antimicrobial susceptibility pattern of methicillin resistant Staphylococcus aureus isolates from Trinidad & Tobago.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) has become increasingly prevalent worldwide since it was first reported in a British hospital. The prevalence however, varies markedly in hospitals in the same country, and from one country to another. We therefore sought to document comprehensively the prevalence and antimicrobial susceptibility pattern of MRSA isolates in Trinidad and Tobago. METHODS: All Staphylococcus aureus isolates encountered in routine clinical specimens received at major hospitals in the country between 2000 and 2001 were identified morphologically and biochemically by standard laboratory procedures including latex agglutination test (Staphaurex Plus; Murex Diagnostics Ltd; Dartford, England); tube coagulase test with rabbit plasma (Becton, Dickinson & Co; Sparks, MD, USA), and DNase test using DNase agar (Oxoid Ltd; Basingstoke, Hampshire, England). MRSA screening was performed using Mueller-Hinton agar containing 6 mug oxacillin and 4% NaCl, latex agglutination test (Denka Seiken Co. Ltd, Tokyo, Japan) and E-test system (AB Biodisk, Solna, Sweden). Susceptibility to antimicrobial agents was determined by the modified Kirby Bauer disc diffusion method while methicillin MICs were determined with E-test system. RESULTS: Of 1,912 S. aureus isolates received, 12.8% were methicillin (oxacillin) resistant. Majority of the isolates were recovered from wound swabs (86.9%) and the least in urine (0.4%) specimens. Highest number of isolates was encountered in the surgical (62.3%) and the least from obstetrics and gynaecology (1.6%) facilities respectively. Large proportions of methicillin sensitive isolates are >85% sensitive to commonly used and available antimicrobials in the country. All MRSA isolates were resistant to ceftriaxone, erythromycin, gentamicin and penicillin but were 100% sensitive to vancomycin, rifampin and chloramphenicol. CONCLUSION: There is a progressive increase in MRSA prevalence in the country but the present rate is still low in comparison to values in some other countries. Vancomycin is still the drug of choice for treating multidrug resistant MRSA infections. Further use of molecular studies to monitor the epidemiology of MRSA in these hospitals in the country is highly recommended too.

Prevalence and antimicrobial susceptibility pattern of methicillin resistant Staphylococcus aureus isolates from Trinidad & Tobago

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) has become increasingly prevalent worldwide since it was first reported in a British hospital. We therefore sought to document comprehensively the prevalence and antimicrobial susceptibility pattern of MRSA isolates in Trinidad and Tobago. METHODS: All Staphylococcus aureus isolates encountered in routine clinical specimens received at major hospitals in the country between 2000 and 2001 were identified morphologically and biochemically by standard laboratory procedures including latex agglutination test. MRSA screening was performed using Mueller-Hinton agar containing 6 g oxacillin and 4 per cent NaCl, latex agglutination test (Denka Seiken Co. Ltd, Tokyo, Japan) and E-test system (AB Biodisk, Solna, Sweden). Susceptibility to antimicrobial agents was determined by the modified Kirby Bauer disc diffusion method while methicillin MICs were determined with E-test system. RESULTS: Of 1,912 S. aureus isolates received, 12.8 per cent were methicillin (oxacillin) resistant. Majority of the isolates were recovered from wound swabs (86.9 per cent) and the least in urine (0.4 per cent) specimens. Highest number of isolates was encountered in the surgical (62.3 per cent) and the least from obstetrics and gynaecology (1.6 per cent) facilities respectively. Large proportions of methicillin sensitive isolates are >85 per cent sensitive to commonly used and available antimicrobials in the country. All MRSA isolates were resistant to ceftriaxone, erythromycin, gentamicin and penicillin but were 100 per cent sensitive to vancomycin, rifampin and chloramphenicol. CONCLUSION: There is a progressive increase in MRSA prevalence in the country but the present rate is still low in comparison to values in some other countries. Vancomycin is still the drug of choice for treating multidrug resistant MRSA infections.

Blood lead levels in primary school children in Trinidad and Tobago.

This study is the first national baseline survey of blood lead levels (BLLs) conducted on primary school children (ages 5-7 years) in Trinidad and Tobago. A total of 1,761 students from 61 schools participated in the study over a 3-month period. Measurements of capillary BLLs were assessed as well as responses to a risk assessment questionnaire. BLLs ranged from <1 microg/dL to 28.6 microg/dL with a geometric mean of 2.8 microg/dL, which compared favourably with results from the U.S. 1991-94 National Health and Nutrition Examination Survey. Fifteen (0.9%) children had a BLL>or=10 microg/dL (10.8-28.6 microg/dL) of which three (0.2%) met the U.S. criteria for lead poisoning (BLL>or=20 microg/dL). Further environmental investigations are required to identify source(s) of lead exposure in cases with high BLL.

Comparison of prevalence and severity of asthma among adolescents in the Caribbean islands of Trinidad and Tobago: results of a nationwide cross-sectional survey.

BACKGROUND: Asthma is a growing problem in the Caribbean but the prevalence in most islands is unknown and possible inter-island variation in prevalence has not been determined. A nationwide cross-sectional survey was conducted to compare the prevalence of asthma symptoms among high school students in the two islands of the Republic of Trinidad and Tobago. METHODS: Questionnaire and video instruments based on those developed by the International Study of Asthma & Allergy in Childhood (ISAAC) were used to assess asthma prevalence among 6394 children (age range, 11-19 years; mean age, 14.08 yrs) in the second and third years of 35 randomly selected high schools in Trinidad and Tobago. This cross sectional survey was conducted between September and December 2002. RESULTS: A total of 4988 questionnaires were available for analysis (3519 in Trinidad and 1469 in Tobago). Among respondents from the two islands, there were no significant differences in the prevalence of ever wheezing (24.1% and 24.3% for Trinidad and Tobago, respectively, RR 0.99, 95% CI, 0.90-1.08); wheezing in the previous 12 months (13.1% & 13.4%, RR 0.98, 95% CI 0.84-1.15); a previous or current diagnosis of asthma (12.8% & 13.5%, RR 0.95, 95% CI 0.82-1.12) and night cough in the past 12 months (35.4% & 38.3%, RR 0.93, 95% CI 0.86-1.00). However, symptoms of severe asthma were significantly more common among students from Tobago and included having had more than one acute attack in the past year (13.4% & 15.8%, RR 0.85, 95% CI 0.73-1.00, p = 0.0004), night waking as a result of wheeze (7.4% & 10.9%, RR 0.68, 95% CI 0.56-0.83, p < 0.0001) and speech limitation in the past year (5.2% & 8.7%, RR 0.59, 95% CI 0.47-0.74, p < 0.001) Exercise-associated wheezing was also more frequent among Tobagonian adolescents (17.5% & 20.2%, RR 0.87, 95% CI 0.76 - 0.98, p = 0.04). CONCLUSION: Self-reported wheeze is common among adolescents in Trinidad and Tobago. Variation in symptoms was found between the two territories; high school students from Tobago, the less industrialized of the two islands, reported more symptoms of severe asthma and exercise-induced wheeze. Difference in the ethnic composition rather than socio-economic factors may be contributing to the observed differences in symptom prevalence.

Comparison of prevalence and severity of asthma among adolescents in the Caribbean islands of Trinidad and Tobago: results of a nationwide cross-sectional survey

BACKGROUND: A nationwide cross-sectional survey was conducted to compare the prevalence of asthma symptoms among high school students in the two islands of the Republic of Trinidad and Tobago. METHODS: Questionnaire and video instruments based on those developed by the International Study of Asthma & Allergy in Childhood (ISAAC) were used to assess asthma prevalence among 6394 children (age range, 11–19 years; mean age, 14.08 yrs) in the second and third years of 35 randomly selected high schools in Trinidad and Tobago. RESULTS: A total of 4988 questionnaires were available for analysis (3519 in Trinidad and 1469 in Tobago); wheezing in the previous 12 months (13.1 per cent & 13.4 per cent, RR 0.98, 95 per cent CI 0.84–1.15); a previous or current diagnosis of asthma (12.8 per cent & 13.5 per cent, RR 0.95, 95 per cent CI 0.82–1.12) and night cough in the past 12 months (35.4 per cent & 38.3 per cent, RR0.93, 95 per cent CI 0.86–1.00). However, symptoms of severe asthma were significantly more common among students from Tobago and included having had more than one acute attack in the past year (13.4 per cent & 15.8 per cent, RR 0.85, 95 per cent CI 0.73–1.00, p = 0.0004), night waking as a result of wheeze (7.4 per cent & 10.9 per cent, RR 0.68, 95 per cent CI 0.56–0.83, p < 0.0001) and speech limitation in the past year (5.2 per cent & 8.7 per cent, RR 0.59, 95 per cent CI 0.47–0.74, p < 0.001) Exercise-associated wheezing was also more frequent among Tobagonian adolescents (17.5 per cent & 20.2 per cent, RR 0.87, 95 per cent CI 0.76 – 0.98, p = 0.04). CONCLUSION: Self-reported wheeze is common among adolescents in Trinidad and Tobago. Variation in symptoms was found between the two territories; high school students from Tobago, the less industrialized of the two islands, reported more symptoms of severe asthma and exercise-induced wheeze.

Smoking at home is strongly associated with symptoms of asthma and rhinitis in children of primary school age in Trinidad and Tobago.

OBJECTIVE: To compare, in the twin-island republic of Trinidad and Tobago, the prevalence of symptoms of asthma and rhinitis among children of primary school age who are exposed to household environmental tobacco smoke with the prevalence of these symptoms in their colleagues without this exposure. METHODS: Between September and December 2002, questionnaires based on the instrument developed for the International Study of Asthma and Allergies in Childhood (ISAAC) were distributed, via the children in their schools, to parents of 6,611 Year 2 pupils (typically 6 years old) or Year 3 pupils (typically 7 years old) in 106 randomly selected schools in Trinidad and Tobago (5,511 pupils on Trinidad and 1,100 pupils on Tobago). We added to the standard ISAAC questionnaires two questions, one on household smoking and one on the ethnicity of the children. RESULTS: A total of 3 170 completed questionnaires were suitable for further analysis (2,618 from Trinidad and 552 from Tobago). On Trinidad 782 of the children (29.9%) lived in homes where one or both parents smoked, and 513 (19.6%) had other relatives in the household who smoked. On Tobago 94 of the pupils (17.0%) had parents who smoked, and 84 (15.4%) came from homes where other residents smoked. Parental smoking was significantly associated with wheezing (odds ratio (OR): 1.43; 95% confidence interval (CI): 1.11-1.83), exercise-induced wheezing (OR: 2.12; 95% CI: 1.59-2.82), nocturnal coughing (OR: 1.64; 95% CI: 1.37-1.97), and symptoms of rhinitis (OR: 1.35; 95% CI: 1.10-1.65) in the last 12 months as well as a history of hay fever/sinus problems (OR: 1.39; 95% CI: 1.11-1.74). Smoking in the home by adult residents other than parents was also significantly associated with all of these symptoms as well as a history of asthma (OR: 1.49; 95% CI: 1.13-1.97). In terms of ethnic differences, parental smoking was most prevalent in the homes of South Asian students, while smoking by other adults in the home occurred most commonly in the households of pupils of mixed race. CONCLUSIONS: Even in Trinidad and Tobago, which is a tropical environment where more time is spent outdoors and homes have more open ventilation than in temperate climates, environmental tobacco smoke exposure is closely associated with an increased prevalence of symptoms of asthma and rhinitis in primary-school-aged children.

Smoking at home is strongly associated with symptoms of asthma and rhinitis in children of primary school age in Trinidad and Tobago

OBJETIVO: Comparar, en las dos islas que integran la república de Trinidad y Tabago, la prevalencia de síntomas de asma y de rinitis en escolares de primaria expuestos al humo de tabaco en el ambiente domiciliario con la prevalencia de los mismos síntomas en coetáneos sin la exposición. MÉTODOS: Entre septiembre y diciembre de 2002, se distribuyeron cuestionarios basados en el instrumento elaborado para el Estudio Internacional de Asma y Alergias en la Niñez (ISAAC, por International Study of Asthma and Allergies in Childhood). La distribución la efectuaron los escolares de 106 escuelas escogidas aleatoriamente en Trinidad y Tabago (5 511 escolares en Trinidad y 1 100 en Tabago) entre los padres de 6 611 escolares de segundo o tercer grado (por lo general de 6 y 7 años de edad, respectivamente). Añadimos dos preguntas al cuestionario ISAAC, una de ellas sobre el tabaquismo en el domicilio y la otra sobre el origen étnico de los niños. RESULTADOS: Un total de 3 170 cuestionarios llenados se prestaron a análisis (2 618 de Trinidad y 552 de Tabago). En Trinidad 782 (29,9%) de los niños vivían en hogares donde uno de los padres o ambos padres fumaban, y 513 (19,6%) tenían otros parientes en el domicilio que fumaban. En Tabago 94 de los niños (17,0%) tenían padres que fumaban y 84 (15,4%) venían de hogares donde otros residentes fumaban. El tabaquismo en los padres mostró una asociación significativa con la presencia de sibilancias (razón de posibilidades [RP]: 1,43; intervalo de confianza de 95% [IC95%]: 1,11û 1,83), sibilancias provocadas por el ejercicio (RP: 2,12; IC95%: 1,59û2,82), tos nocturna (RP: 1,64; IC95%: 1,37û1,97) y síntomas de rinitis (RP: 1,35; IC95%: 1,10û1,65) en los 12 meses más recientes, así como antecedentes de fiebre del heno o problemas sinusales (RP: 1,39; IC95%: 1,11û1,74). La presencia en el domicilio de parientes fumadores distintos de los padres también mostró una asociación significativa con todos estos síntomas y con antecedentes de asma (RP: 1,49; IC95%: 1,13û1,97). En cuanto a diferencias por razones étnicas, el tabaquismo de los padres fue más frecuente en los hogares de escolares del sur del Asia, mientras que el tabaquismo de otros adultos en el domicilio se observó con más frecuencia en los hogares de escolares de raza mixta...