Prevalence and risk factors of airflow obstruction in a Caribbean population.

SETTING: The prevalence of airflow obstruction (AO) in the Caribbean population is unknown.OBJECTIVE: To measure the prevalence of and risk factors for AO (post-bronchodilator ratio of forced expiratory volume in 1 sec to forced vital capacity of <0.7) in the Trinidad and Tobago general population using the Burden of Obstructive Lung Disease methodology.DESIGN: National cross-sectional, stratified, cluster sampling of adults aged ≥40 years.RESULTS: AO prevalence was 9.5% among 1104 participants, most of whom were unaware of this. Compared to those aged 40-49 years, the adjusted odds ratio of AO by age group was 2.73 (60-69 years) and 3.30 (≥70 years). Risk factors for AO were unemployment (OR 4.31), being retired (OR 2.17), smoking ≥20 pack-years (OR 1.88) and exposure to dusty jobs for more than 1 year (OR 2.06). Related symptoms were history of wheezing, unscheduled visits to the doctor or admission to hospital for breathing problems and in subjects with at least one respiratory symptom (OR 1.90), at least one risk factor (OR 2.81), either symptoms or risk factors (OR 3.71) and both symptoms and risk factors (OR 5.78) (P < 0.05 in all cases).CONCLUSION: AO prevalence in the general population of Trinidad and Tobago aged ≥40 years was 9.5%, almost all of which was undiagnosed. AO was associated with smoking, age >59 years, lack of employment and working in a dusty job.

Occupational dust exposure is independently associated with Chronic Obstructive Pulmonary Disease (COPD) in Trinidad and Tobago population

Objective: COPD is a leading cause of mortality and morbidity worldwide. Although cigarette smoking is a well-known risk factor for COPD, nonsmokers may account for one fourth to half of all cases. The Burden of Obstructive Lung Disease in Trinidad and Tobago (BOLD-TT) study objective was to measure the COPD prevalence and its risk factors in the local population aged 40 years and older. Design and Methodology: In this cross-sectional survey participants were selected using two-stage stratified-cluster sampling to represent the national population in terms of gender, age and ethnic distributions. Quality assured spirometry and questionnaires were administered. Results: Among the 1,104 participants, 36% reported occupational dust exposure for more than one year and about 40% of them were never-smokers. Overall 9.5% (95% CI: 7.78 to 11.23%) of the studied population showed COPD, accounting for an estimated 49,170 persons (95% CI = 40,267; 58,124) in Trinidad and Tobago. The majority (60%) of the diagnosed COPD was attributable to non-smoking causes, and more than half of them reported occupational dust exposure. Multiple logistic regression analysis confirmed COPD's independent association with working in a dusty job (OR 2.05; 95% CI=1.26, 3.35). Conclusions: Risk of COPD in the Trinidad and Tobago general population is significantly associated with occupational dust exposure which is probably contributing about one-third of current COPD burden. International studies showed that only about 15% of overall COPD could be ascribed to occupational risk factors. The higher occupational related COPD risk in the local population should be further studied prospectively.

Indo-Caribbean population has lower vital capacities than Afro-Caribbean population in Trinidad and Tobago

Objective: Low forced vital capacity (FVC) is a good predictor of mortality and morbidity including cardiovascular disease, diabetes and chronic kidney disease in the general population. Objective of the current post-hoc analysis was to compare the FVCs among the major ethnic groups of Trinidad and Tobago. Design and Methodology: The Burden of Obstructive Lung Disease in Trinidad and Tobago (BOLD-TT) study was conducted to measure the COPD prevalence and its risk factors in the local population of 40 years and older by using questionnaires and quality assured spirometry. The participants were selected using two-stage stratified, cluster sampling to represent the national population in terms of gender, age and ethnic distributions. To avoid the influence of contentious international spirometry predictive values, FVC was used as a continuous variable after adjusting for age, gender, height and height square. Results: Among the 1,104 participants, 42% were Indo- Caribbeans, and 36% were Afro-Caribbeans. Indo- Caribbeans had a similar prevalence of abnormal waist circumference (57.0% vs. 58.7%; p=0.751), a lower prevalence of obesity (30.0% vs. 41.8%; p=0.008), but a higher prevalence of abnormal waist-hip ratio (74.1% vs. 57.5%; p<0.001) and diabetes (21% vs. 10%; p<0.001) than the Afro- Caribbeans. Multiple regression analysis indicated that FVC was independently associated with ethnicity and revealed lower volumes in Indo- Caribbean participants than Afro-Caribbeans (-180ml; 95%CI:-90ml,-269ml; p<0.001). Conclusions: The Indo-Caribbean population has a lower FVC than the Afro-Caribbean population which was independent of age, gender, and height. Healthrelated consequences of low FVC among local ethnic groups warrant further research using longitudinal studies.

Universal access to screening and management of diabetes in pregnancy in Trinidad using an ICT solution

Objective: Undetected diabetes in pregnancy (DiP) can lead to deleterious consequences. Strengthening health systems and implementing national standardized protocols for screening and management can improve outcomes. This study aimed to achieve consensus on clinical guidelines and facilitate universal screening using standardized testing and an app. Design and Methodology: An integrated care model was developed and antenatal caregivers were trained on screening and management of DiP. A secure Information and Communication Technologies (ICT) solution for real-time communication of results was designed and piloted as the reporting system. The app provided automatic alerts to patients and doctors facilitating timely intervention and offered self-management tools. Pregnant women ≥ 18 years, n = 655 at two antenatal clinics in Trinidad (1 public and 1 private hospital) were screened using a standard 75g 2-hour oral glucose tolerance test (OGTT) after an overnight fast. Seven lab technologists and 24 doctors were trained to use the app. Cost-effectiveness was assessed. Results: National consensus was achieved with 197 antenatal caregivers, for universal screening for DiP. The app facilitated a reporting system of blood glucose results and delivered real-time SMS text and e-mail alerts to participants. 10.1% of participants had abnormal fasting glucose and 14.1% had at least one abnormal reading between 0hr to 2hrs. Universal screening for GDM was cost-effective in the local setting. Results: National consensus was achieved with 197 antenatal caregivers, for universal screening for DiP. The app facilitated a reporting system of blood glucose results and delivered real-time SMS text and e-mail alerts to participants. 10.1% of participants had abnormal fasting glucose and 14.1% had at least one abnormal reading between 0hr to 2hrs. Universal screening for GDM was cost-effective in the local setting. Conclusions: The high prevalence of DiP in T&T justifies the need for universal screening and related health systems change. Training healthcare teams in DiP screening and ICT-enabled management are essential elements of a standardized health system which features real-time reporting.

Asymptomatic 'normal' subjects may have a respiratory health burden as assessed by the St Georges Respiratory Questionnaire (SGRQ)

Objectives: The Burden of Obstructive Lung Disease study in Trinidad and Tobago identified subjects with obstruction and no symptoms in approximately 5% of the general population over 40 years old. We reviewed data from a previously published study involving asymptomatic subjects to determine respiratory health burden and relation to lung function. Results: Subject characteristics were: 16 (64%) males, Mean (SD) age 64.8 (6.78) years, forced expiratory volume (FEV1) 2.25 (0.77)L, forced vital capacity (FVC) 2.91 (1.02) L, FEV1/FVC 78.1 (8.31)%. Parameters assessed were FEV1 (1.21 to 3.69 L); FVC (1.32 to 4.88 L); FEV1/FVC (65.2 - 94.7%); SGRQ Total Score (0 to 20.8). Three subjects (12%) had a FEV1/FVC ratio of less than 70%. The correlations (rho, p) of total SGRQ scores were FEV1 (-0.62, 0.001), FEV1% (-0.52, 0.008); FVC (-0.69, < 0.001). Conclusion: Asymptomatic normal elderly subjects had significant respiratory health burden as measured by the SGRQ and this was worse in those with a lower FEV1%. This may apply to elderly persons in the general population.

Sex and social class inequities in physical and mental health: an analysis using data from the Burden of Obstructive Lung Disease Trinidad and Tobago (BOLD-TT) study

Objectives: To examine sex and social class differences in physical and mental health in the Trinidad and Tobago population aged ≥40 years. Design and Methodology: Data from the BOLD-TT study, which included a stratified cluster sample of 1104 persons, were analysed. The Veteran Rand (VR)-12 instrument assessed physical (general health, physical functioning and role playing and bodily pain) and mental health (vitality, role-emotional, mental health and social functioning); using a physical health component (PCS) and mental health component (MCS) scores. Highest level of education attained, and employment status were used as measures of social class. General Linear Models were used to examine differences in PCS and MCS by sex, education and employment, controlling for age. Results: Mean age of the participants was 54.1 (SD10.8) years; 59.9% were females; 47% had no/primary education; 56% were employed. Mean PCS and MCS (SEM) scores were 47.8 (0.3) and 54.7 (0.3). Females had lower mean PCS and MCS than males (p<.001 in each case). There were significant mean differences in PCS (p<.001) and MCS (p=.04) by employment status. Persons who were not working had lower mean PCS (p<.001) and MCS (p=.002) than those employed. There were differences in PCS by education (p=.019); persons with no/primary education had lower PCS than those with post-secondary and university education. Multiple regression identified employment (p<.001) and education (p=.097) as independent predictors of PCS while sex (p=.002) and employment (p=.021) predicted MCS. Conclusion: The VR-12 provided initial results indicating health inequities i.e. poorer health status among females, the unemployed and uneducated.

Prevalence of COPD in Trinidad and Tobago - A National Study

Purpose: Chronic Obstructive Pulmonary Disease (COPD) is preventable and treatable, yet it is the third leading cause of death and fifth leading cause of disability globally. Local studies in restricted settings have reported about 20% COPD prevalence, but the national prevalence and risk factors are unknown. We aimed to measure the prevalence of COPD and its risk factors in Trinidad and Tobago as part of the multicentre Burden of Obstructive Lung Disease (BOLD) Study. Research Design and Methodology Used: A cross-sectional study was conducted during 2014-2015 using the BOLD standardised protocol. A stratified cluster sample of non-institutionalised males and females aged ≥ 40 years (N = 1104) and a sample of 18-39 year olds (N = 807) were selected. Questionnaires on respiratory symptoms, health status, and exposure to COPD risk factors were administered and spirometry conducted before and after bronchodilator. Spirometry quality control measures utilised were (1) direct spirometer feedback and (2) BOLD international centre review. Spirometry readings below international standards required technician retraining. Post- bronchodilator forced expiratory volume in the first second of expiration (FEV1) was expressed as a percentile of the forced vital capacity (FVC). COPD was defined by FEV1/FVC < 70% and a smoker as having smoked >200 cigarettes in a lifetime. Logistic regression was used to examine associations a (expressed as Odds Ratios (OR) and multivariate logistic regression to determine independent risk factors. Findings: There was a 95% response rate The mean age (SD) of these participants was 54 (11) years and Body Mass Index (BMI) 29 (7) kg/m2; with N (%) males, 443 (40) males; Afro-Trinidadians 400 (37), Indos 454(42), Mixed 234 (21), ever-smokers 302 (27), current smokers 157 (14), Adverse events 13(<1%)]. The prevalence of COPD was 9.5%, Of those with COPD, only 4% reported a previous doctor diagnosed COPD. COPD was more likely among those aged 60-69 years or over 70 (OR=4.15 and 5.88 respectively, p<0.001), among males (OR=1.64, p=0.023), ever smokers (OR=1.72, p=.016), retirees and the unemployed (OR=4.41 and 3.59 respectively, p<.001), with BMI<21 (OR=2.64, p=.001), asthma (OR=5.20, p<.001) or wheezing (OR=3.48, p<.001). Multivariate analysis showed significant risk factors for COPD were: older age groups, low BMI, working over a year in dusty jobs, cigarette or cannabis smoking. There was no non-responder bias in age, gender, ethnicity, smoking or BMI but unacceptable spirometry was more likely in the elderly and smokers. Among the 807 participants aged 18-39 years old, 23% smoked with the prevalence of smoking in males being 32% vs. 11.7% in females (p < 0.001). Conclusions: COPD is prevalent yet under-diagnosed in the general population. Health care education and use of spirometry for prevention of COPD should target males, the elderly, smokers, those working in dusty jobs and those with a history of asthma or wheeze. We suggest spirometry measurements be available at all district health facilities.

Spirometry quality control: man versus machine

OBJECTIVE: To compare the efficacy of local quality control (QC) of BOLD (Burden of Obstructive Lung Disease) Trinidad and Tobago study with spirometer machine quality grades as well as with BOLD Pulmonary Function Reading Centre QC standards at Imperial College, London. METHODOLOGY: Quality of the randomly chosen two hundred spirometries was independently assessed by the local team based on the 2005 ATS/ERS spirometry standards. Central QC quality assessment results were blinded to the local team. However, the machine quality grades were readily available to both the central and local teams during interpretation. Local and machine QC performances were correlated with the central QC which was taken as the gold standard for this study. RESULTS: According to central QC, 17.5% of the spirometries were declared as unacceptable. The noted common errors were prolonged peak expiratory flow time(14.5%), submaximal blasts (11.5%), variable efforts (11%) and poor reproducibility (10%). Cronbach’s alpha assessment revealed an overall reliability of 0.82 and a correlation of 0.73 between central and local QC. The correlation between central and machine QC was poor(0.548). Local QC exhibited 89.1% sensitivity and 94.3% specificity relative to the central QC. Though the machine QC displayed a better sensitivity (97.6%), its specificity was significantly lower 45.7%). CONCLUSION: Local QC was effective when compared with the central QC and executed better performance than the machine’s QC. This expertise can now be utilized for the future spirometry based local research studies. Due to limitations in identifying various errors, machine QC should not solely be used as the determinant of acceptability.

Association between obesity and lung function among teenagers in Trinidad

OBJECTIVE: To examine association between obesity and lung function among teenagers in Trinidad. SUBJECTS AND METHODS: This study is part of an ongoing five-year cohort study in which five schools in the St.George East educational district of Trinidad were selected and students entering form one were followed up to form three (2012 to 2015). A questionnaire was completed on previous pulmonary disorders, eating and exercise habits along with demographic data. Data were available on 584 male students and 502 female students for three years. Descriptive analyses were performed according to year. General linear model analyses were performed to determine relationship of lung function variable ratio (forcedexpiratory volume in 1st second/forced vital capacity[FEV1/FVC]) to independent variables. RESULTS: Analysis of variance, according to year, showed that among the male students, FEV1, FVC, forced expiratory flow (FEF), peak expiratory flow rate (PEFR)in L/min, waist circumference, diastolic and systolic blood pressure, age and FEV1/FVC (%) were significant,whereas moderate exercise, FEV1, FVC, FEF, PEFR, age and FEV1/FVC (%) were significant in female students. The mean (year of study) PEFR in males were 285 (1), 302(2) and 384 (3). The mean (year of study) PEFR in females were 273 (1), 278 (2) and 338 (3). General linear model analysis showed PEFR to be a common significant factor for FEV1/FVC in both male and female students. In addition to PEFR, age, body mass index (BMI)-for-age-Zscore, ethnicity and interaction of religion and ethnicity were also significant among females. CONCLUSION: Based on results, BMI-for-age-Z-score issignificantly associated with FEV1/FVC in female students, but not in male students.

Correlates of vigorous physical activity in adolescents in five secondary schools in Trinidad

OBJECTIVE: To determine the correlates of vigorous physical activity in adolescents in Trinidad. DESIGN AND METHODS: Adolescents (n = 344) between 11-15 years from five secondary schools in North-central Trinidad were cross-sectionally surveyed. Behavioural risk factors: alcohol and smoking use, physical activity and diet were obtained by a pilot tested interviewer administered questionnaire. In addition, anthropometric measures were obtained on site at school. Multivariate logistical regression was used to analyze correlates of vigorous physical activity by sex. RESULTS: Fruit and vegetable intake (p < 0.001) and religion (p = 0.034) were correlated with vigorous physical activity in females. Lower waist circumference (p = 0.014), age (p = 0.046) and diastolic blood pressure (p < 0.01) were correlated with vigorous physical activity in males. Body mass index (BMI) for age data indicated that 41.3% of the children were overweight or obese. However, vigorous physical activity did not correlate with BMI for age in either sex. In the final logistic regression models, higher vigorous physical activity was associated with lower diastolic blood pressure in males (p < 0.05) and an increased daily intake of fruit and vegetables in females (p < 0.001). CONCLUSION: Increased dietary intake of fruits and vegetables in females and lower diastolic blood pressure in males were associated with higher vigorous physical activity. Prospective studies are required to determine and clarify the relative importance of diet and physical activity in overweight adolescents and their risk of chronic metabolic disease.