Activity, adiposity and weight change in Jamaican adults / Actividad, adiposidad y cambio de peso en los adultos jamaicanos

OBJECTIVE: Populations in developing countries are particularly vulnerable to the development of obesity in the period of rapid transition to a more modernized lifestyle. We sought to determine the relationship between activity energy expenditure (AEE), adiposity and weight change in an adult population undergoing rapid socio-economic transition. METHODS: Total daily energy expenditure (TDEE) was measured using the doubly labelled water method, resting energy expenditure (REE) using indirect calorimetry and AEE calculated as the difference between TDEE and REE, in adults from a working class community in Spanish Town, Jamaica. During six years of follow-up, weight was measured between one and four times. Mixed effects regression modelling was used to test for association between components of the energy budget and weight change. RESULTS: Men (n = 17) weighed more but women (n = 18), had significantly more body fat, 38.5% vs 24.5%, respectively (p < 0.01). Men had higher levels of EE, particularly AEE after adjustment for body weight, 66.3 versus 46.4 kJ/kg.d for men and women, respectively (p < 0.001). At baseline, adjusted AEE was inversely associated with body fat in men and women, r = -0.46 and r = -0.48, respectively (p < 0.05). Mean rate of weight change was + 1.1 and + 1.2 kg/year for men and women, respectively. No component of EE, ie TDEE, REE or AEE, significantly predicted weight change in this small sample. CONCLUSIONS: These results suggest an important role for AEE in maintaining low levels of adiposity. The lack of association between EE and weight change, however, suggests populations in transition are at risk of obesity from environmental factors (eg dietary) other than simply declining physical activity levels.

OBJETIVO: Las poblaciones en los países en vía de desarrollo son particularmente vulnerables al desarrollo de la obesidad en el período de rápida transición a un estilo de vida más moderno. Buscamos determinar la relación entre el gasto energético por actividad (GEA), la adiposidad y el cambio de peso en una población adulta en proceso de rápida transición socio-económica. MÉTODOS: El gasto energético total diario (GETD) fue medido usando el método del agua doblemente marcada, gasto energético en reposo (GER) usando calorimetría indirecta y el GEA calculado como la diferencia entre GETD y GER, en adultos de una comunidad de clase obrera en Spanish Town, Jamaica. Durante seis años de seguimiento, el peso fue medido entre una y cuatro veces. Un modelo de regresión de efectos mixtos fue usado para probar la asociaciF3n entre los componentes del presupuesto de la energEDa y el cambio de peso. RESULTADOS: Los hombres (n = 17) pesaron más pero las mujeres (n = 18) teníEDan significativamente más grasa corporal, 38.5% frente a 24.5%, respectivamente (p < 0.01). Los hombres tenían niveles más altos de GE, particularmente GEA después del ajuste por peso corporal, 66.3 frente a 46.4 kJ/kg.d para los hombres y mujeres, respectivamente (p < 0.001). Al inicio, el GEA ajustado estaba inversamente asociado con la grasa del cuerpo en los hombres y mujeres, r = -0.46 y r = -0.48, respectivamente (p < 0.05). La tasa media de cambio de peso fue +1.1 y +1.2 kg/ano para los hombres y mujeres, respectivamente. Ningún componente de GE, es decir, GETD, GER o GEA, predijo significativamente el cambio de peso en esta muestra pequeña. CONCLUSIONES: Estos resultados sugieren un papel importante del GEA en cuanto a mantener niveles bajos de adiposidad. Sin embargo, la falta de asociación entre GE y cambio de peso, sugiere que las poblaciones en transición corren el riesgo de obesidad debido a factores ambientales (p.ej. dietéticos) distintos de la mera...

Skin test reactivity to aeroallergens in Jamaicans: relationship to asthma / Reactividad de la prueba cutánea frente a aeroalérgenos en los jamaicanos: relación con el asma

BACKGROUND: Asthma causes significant morbidity and mortality in the developing world. It is thus important to identify modifiable risk factors. OBJECTIVES: To undertake a cross-sectional study to determine the prevalence of skin test reactivity to aeroallergens in Jamaican children and adults and the relationship of the diagnosis of asthma to the pattern of skin test positivity. METHODS: One hundred and sixty subjects without the sickle cell gene (genotype AA), eighty adults and eighty children, were recruited. Skin testing to seven aeroallergens was undertaken (atopy being diagnosed if there were at least one positive reaction). Asthma status was determined by a questionnaire and/or medical records. RESULTS: Twenty-seven (34) of the children and forty-one (51) of the adults were skin test positive to at least one aeroallergen. The most common positive responses in both age groups were to Dermatophagoides farinae, Dermatophagoides pteronyssinus and cockroach mix-(German and American). All adult asthmatics with current symptoms reacted to cockroach allergen. CONCLUSIONS: Appropriate steps to reduce cockroaches and cockroach sensitization might positively impact on asthma morbidity in Jamaica.

ANTECíENTES: El asma causa morbilidad y mortalidad significativas en el mundo en desarrollo. Por lo tanto, es importante identificar los factores de riesgo modificables. OBJETIVOS: Llevar a cabo un estudio transversal a fin de determinar la prevalencia de la reactividad de la prueba cutánea frente a los aeroalérgenos en niños y adultos jamaicanos, y la relación del diagnóstico del asma con el patrón de positividad de la prueba cutánea. MÉTODOS: Se reclutaron ciento sesenta sujetos AA (sin genes falciformes), ochenta adultos y ochenta niños. Se llevaron a cabo pruebas cutáneas frente a siete aeroalérgenos (diagnosticándose atopia si se producía al menos una reacción positiva). El estatus asmático se determinó mediante encuestas y/o historias clínicas. RESULTADOS: Veintisiete (34%) de los niños y cuarenta y uno (51%) de los adultos, resultaron positivos en la prueba cutánea, al menos a un aeroalérgeno. Las respuestas positivas más comunes en ambos grupos de edad fueron frente a Dermatophagoides farinae, Dermatophagoides pteronyssinus, y mezcla de cucarachas (alemanas y americanas). Todos los asmáticos adultos con síntomas usuales reaccionaron al alérgeno de la cucaracha. CONCLUSIONES: Medidas apropiadas a fin de reducir las cucarachas y la sensibilización a las cucarachas podría tener un impacto positivo en la morbilidad por asma en Jamaica.

Iron deficiency anaemia in Jamaican children, aged 1-5 years, with sickle cell disease / Anemia por deficiencia de hierro en los niños jamaicanos entre 1 y 5 años de edad, que padecen la enfermedad de células falciformes

OBJECTIVE: The aim of this study was to determine, using a combination of measures, the prevalence of iron deficiency anaemia (IDA) in children under five years-of-age who have sickle cell disease (SCD) and attend the Sickle Cell Clinic (SCU) of the Tropical Medicine Research Institute. MATERIALS AND METHODS: Children with homozygous sickle cell anaemia (Hb SS) or doubly heterozygous for Hb S and Hb C (Hb SC) disease who had not received a blood transfusion within three months prior to the iron measurements, were enrolled. The diagnosis of IDA was made if transferrin saturation was less than 16with serum iron less than 10.7 micromol/l and a low mean corpuscular volume (MCV) for age. RESULTS: Twelve children (8.5), seven with Hb SS and five with Hb SC had IDA. Adjusting for genotype, children with IDA had significantly higher red blood cell (RBC) counts (4.3 x10(9)/l vs 3.0 x 10(9)/l, p < 0.001) and total iron binding capacity (TIBC) (65.6 micromol/l vs 55.2 micromol/l, p < 0.004) but significantly lower reticulocyte (retic) counts (7.8vs 12.2, p = 0.001) than children without IDA. CONCLUSION: Iron deficiency anaemia is a clinical problem which affects children with SCD in Jamaica. The higher RBC counts in the IDA group may be due to decreased haemolysis and increased red cell survival whilst the lower reticulocyte counts may be due to impaired erythropoiesis. These observations need to be extended by clinical studies to establish improved diagnostic measures for IDA in SCD. Additionally, clinical trials are needed to determine whether treatment of IDA in children with SCD reduces morbidity and is associated with clinical benefits such as improvements in neurocognitive function.

OBJETIVO: El objetivo de este estudio fue determinar – mediante una combinacion de medidas – la prevalencia de anemia por deficiencia de hierro (ADH) en ninos menores de cinco anos de edad que padecen la enfermedad de celulas falciformes (ECF), y asisten a la Clinica de Celulas Falciformes (CCF) del Instituto de Investigacion de Medicina Tropical. MATERIALES Y MÉTODOS: Se inscribieron ninos con anemia de celulas falciformes homocigoticas (Hb SS) o enfermedad doble heterocigoto por Hb S y Hb C (Hb SC), que no habian recibido transfusion de sangre por un periodo de tres meses antes de las mediciones de hierro. Se diagnosticaba ADH si la saturacion de la transferrina era menos del 16%, con hierro en suero inferior a 10.7 mol/l, y un volumen corpuscular medio (VCM) bajo para la edad.RESULTADOS: Doce ninos (8.5%), siete con Hb SS y cinco con Hb SC presentaban ADH. despues del ajuste de las diferencias en el genotipo, los ninos con ADH tuvieron conteos de globulos rojos (RBC) (4.3 x109/l vs 3.0 x 109/l, p < 0.001), y capacidad total de fijacion del hierro (TIBC) (65.6 mmol/l vs 55.2 mmol/l, p < 0.004) significativamente mas altos, pero conteos de reticulocitos (7.8% vs 12.2%, p = 0.001) significativamente mas bajos que los ninos sin ADH. CONCLUSIÓN: La anemia por deficiencia de hierro es un problema clinico que afecta a los ninos con ECF en Jamaica. El hecho de que los conteos de RBC sean mas altos en los grupos con ADH, puede deberse a una disminución de la hemólisis y un aumento de la upervivencia de glóbulos rojos, en tanto que los conteos más bajos de reticulocitos pueden deberse a problemas de eritropoyesis. Estas observaciones necesitan ser ampliadas mediante estudios clínicos para establecer las medidas de diagnóstico mejoradas para ADH en ECF. Además de ello, se requieren ensayos clínicos a fin de determinar si el tratamiento de ADH en niños con ECF reduce la morbosidad y se halla asociado con beneficios clínicos...

Features of isolated post-challenge hyperglycaemia in Jamaican adults

Isolated post-challenge hyperglycaemia (IPH) can be defined as a two-hour plasma glucose concentration > or = 11.1 mmol/L with a fasting plasma glucose concentration < 7.0 mmol/L. The aim of this prospective study was to determine the prevalence of IPH in a cohort of Jamaican individuals, and to determine if simple clinical features may predict the presence and subsequent diagnosis of IPH. A cohort of 1694 adults aged 25-74 years without physician-diagnosed diabetes mellitus was randomly selected. An oral glucose tolerance test (OGTT) was performed. Anthropometry, blood pressure and lipid profiles were measured. The prevalence of undiagnosed diabetes mellitus by the 1999 World Health Organization criteria was 6.4. IPH accounted for 24 of these cases and 1.4 of the entire population. Individuals with IPH were significantly older, with greater body mass index, waist-hip ratio, systolic blood pressure, fasting blood glucose, total cholesterol and LDL-cholesterol than individuals with normal glucose tolerance. Individuals with IPH were not significantly different from individuals with fasting plasma glucose levels > or = 7 mmol/L (i.e. fasting hyperglycaemia) in anthropometry or blood pressure. However, total cholesterol and LDL-C were significantly elevated in the IPH group. OGTT screening of individuals with impaired fasting glucose (i.e. 6.1-6.9 mmol/l) could reduce the IPH group by 50. Reducing the threshold for fasting glucose to 5.6 mmol/L would correctly classify 87 of the population. We concluded that individuals with IPH have features of the metabolic syndrome, which can aid in selection for screening. OGTT screening of individuals with fasting glucose values of 5.6-6.9 mmol/l is needed to identify IPH

Nutritional status of older adults in urban Jamaica

The aim of the study was to determine the energy intake and nutritional status of a sample of Jamaican adults, and to compare them among different age groups. Measured height and weight data from a survey in Spanish Town, Jamaica, consisting of 2100 adults aged 25-74 years, with 22 per cent over age 60 years, were used to calculate body mass index (BMI). Using BMI cut-off points of 20 and 27, the prevalence of underweight and overweight, respectively, were determined for different age groups. Energy intake was calculated from a food frequency questionnaire from 967 of the respondents. Among males, mean daily energy intake declined from a high of 3681 kcal (15,401 kJ) for 25-29 year-olds, to a low of 2227 kcal (9318 kJ) for those aged 70-74 years. Corresponding numbers among females were 2935 kcal (12,280 kJ) and 1844 kcal (7715 kJ), respectively. Among those aged 65-74 years, 26.9 per cent of males and 50 per cent of females report daily energy intakes of less than 1600 kcal (6694 kJ) (below the lowest recommended dietary allowance (RDA)), compared to 4.5 and 13.7 per cent of males and females aged 25-34 years. While there are moderate declines in the prevalence of overweight, the prevalence of male underweight increased from 4 per cent among 50-54 year-olds to over 35 per cent among those 65 years and older; and among females the corresponding numbers are from 2 per cent to 10 per cent. All trends with age were significant (p < 0.005). There are significant declines in energy intake, and alarming increases in the prevalence of underweight with increasing age among males. These results are cause for concern and further research in this area is warranted

Ultrasound derived fetal growth curves for a Jamaican population

The objective of this study was to develop fetal growth curves and percentile growth charts for a Jamaican population. Four hundred and ninety-nine Jamaican women of African origin were enrolled in a prospective study from the antenatal clinic of the University Hospital of the West Indies, Kingston, Jamaica. Serial ultrasound scans were performed between 14 and 37 weeks gestation to measure fetal growth. The ultrasound measurements performed were biparietal diameter, head and abdominal circumference and femoral length. A total of 2574 ultrasound scans were performed on the 499 women (mean 5.2 per woman). From these data, centiles for fetal growth curves for the four fetal measurements were constructed and percentile tables were created for a Jamaican population. Birthweight varies between ethnic groups and, therefore, so must fetal growth rates. At present, fetal growth in Jamaica is assessed using standards which are based on data derived from Caucasian populations. Fetal growth curves using data from this study would more accurately identify a fetus that is at risk and hence, provide information which could improve obstetric care. These new growth curves should provide data, which will improve obstetric decision making

Primary malnutrition. Can we always tell?

Patterns of disease in the English-speaking Caribbean have changed considerably over the past two decades. There has been a decrease in the incidence of common infectious diseases, an increase in the prevalence of chronic non-communicable disorders and an increase in the incidence and prevalence of HIV/AIDS. However, published estimates suggest that malnutrition continues to be a serious public health problem. It is possible that changing patterns of disease within the epidemiological transition may affect patterns of presentation of severe forms of childhood malnutrition. We have examined records of 435 children admitted to the clinical research ward of the Tropical Metabolism Research Unit (TMRU) from January 1, 1990, to December 31, 1999; among these were 25 children who were subsequently found to have severe childhood malnutrition (SCM) due to a defined medical or surgical disorder (i.e. secondary SCM). Among children with secondary SCM, the HIV/AIDS group was the largest and comprised 60 of these admissions. Regression analyses show that, over the ten-year period, there was a small, non-significant decline in the number of cases of primary SCM (incidence rate ratio, IRR = 0.99, 95 confidence interval = 0.96, 1.02, p = 0.98), while the number of cases of secondary SCM increased (IRR = 1.18, 95 CI = 1.03, 1.35, p = 0.02). These data are indicative of the need for continued vigilance in the evaluation of children who have clinical features of the syndromes of severe malnutrition and draw attention to the potential impact of HIV/AIDS in yet another area of healthcare delivery.

Chronic diseases--facing a public health challenge

Middle income countries like those in the Caribbean can feel proud of their achievements in health care. There has been a dramatic fall-off in infant mortality and crude mortality rates along with significant improvements in life expectancy at birth. However, these countries now find themselves grappling with the burden of chronic non-communicable diseases such as heart disease, stroke, hypertension, diabetes mellitus and cancer. There are good data to support the view that some of these diseases, in particular diabetes mellitus, have assumed epidemic proportions and there is concern that this fact may have been missed by many because of the surreptitious onset, as is the nature of the chronic diseases. The impact of this epidemic may have suffered because of the higher profile of more topical issues like HIV/AIDS even though the former makes a larger contribution to morbidity and mortality statistics. It is now obvious that despite the impact of other factors, lifestyle changes are the major contributors to the epidemic. In populations of similar genetic stock, living in significantly different socio-economic circumstances, the impact of increased dietary salt, increasing obesity and decreased physical activity on the prevalence of hypertension, diabetes mellitus and lipid disorders is unequivocal. Data from the developed world, which has already been through this epidemic of chronic diseases, have shown that increasing technological advances in medical care is an inefficient way to respond to the situation. A multi-sectoral approach is required to tackle this epidemic, including the provision of incentives for healthy eating and widespread opportunities for increased exercise and other physical activities. Continued research into the evolution of the epidemic, including reliable estimates via surveillance methods is a necessary component of our response. The problems and the solutions are not only the responsibilities of the health officials but must involve education, agriculture and other sectors of the economy.

The appropriateness of the current antibiotic empiric therapy based on the bacteria isolated from severely malnourished Jamaican children

We performed a retrospective audit of antimicrobial sensitivities of bacteria isolated from children admitted with a diagnosis of malnutrition to the Tropical Metabolism Research Unit (TMRU), University of the West Indies, between January 1995 and December 1999. There were 150 admissions for severe malnutrition to the TMRU during this period, which was approximately 50 fewer than in a previous TMRU study done ten years ago, between 1984 and 1989. In the present study, bacteraemia was documented in 10 of 150 severely malnourished children between 1 and 31 months of age. The most common organisms isolated were coagulase-negative Staphylococci, which represented 40 of the total isolates. The micro-organisms grown were most likely to be sensitive to amoxycillin/clavulanic acid. The current TMRU treatment protocol for severe malnutrition recommends use of crystalline penicillin plus gentamicin as empirical antibiotic therapy. This study has provided valuable information suggesting that the current empiric antibiotic therapy may be inappropriate.

A comparative study of pregnancy outcome in teenage girls and mature women

The objective was to compare the pregnancy outcome of teenage girls and mature women. The design was a retrospective study of births from January to December 1990, based on the antenatal clinic and the labour ward, University Hospital of the West Indies, Jamaica. Teenage mothers, 13 to 19 years old, and a control group of mothers, 22 to 23 years old, were selected from the records of 2,394 live, singleton births between 200 and 305 days' gestation. The main outcome measures were birth weight, crown heel length, head circumference, head circumference:length ratio, ponderal index and placental weight. The results showed that in the teenage group, weight, body mass index at booking, haemoglobin concentration in each trimester, and minimum haemoglobin level during pregnancy were lower than in the control group. Systolic blood pressure in the first and the second trimesters was lower than in controls, but there was no significant difference in the third trimester nor in the delivery systolic blood pressure. Babies of teenage mothers had lower birth weights and smaller head circumferences than the babies of the control group, but there was no significant difference between the groups in crown heel length, ponderal index, head circumference:length ratio, and placental weight. These data support the hypothesis that teenaged girls are not physically mature and, as a consequence, their offspring have lower birth weights and smaller head circumferences.

Blood pressure in Jamaican children: relationship to body size and composition

Blood pressure levels in adults and children are related to body size and composition, but some of these relationships are unclear and they have been incompletely described in the Jamaican population. In a cross-sectional survey of 2,332 school children (6-16 years old; 1,046 boys, 1,286 girls), we measured systolic and diastolic blood pressure and pulse rate, and explored their relationship to weight, height, and waist, hip and mid-upper arm circumferences. The effect of these and other derived measures of body composition on blood pressure was explored in univariate and multivariate analysis. Blood pressure increased with age in both boys and girls, although the increase was greater for systolic than for diastolic blood pressure. The increase of systolic blood pressure among boys continued after age 11 years, but that for girls levelled off. Height and weight were the major predictors of blood pressure, but were highly correlated with each other and with all measures of body composition. Age, height and height-sex interaction explained 11.4of systolic blood pressure variation, and the largest incremental contribution to this model was provided by the addition of body mass index or hip circumference, each explaining an additional 2.6of the variance. Lean body mass made a larger contribution to blood pressure than percent fatness. Blood pressure in Jamaican children rises with age and this rise may be steeper in boys than girls. Blood pressure variation is significantly related to several measures of body composition including measures of fatness and fat free mass.

Chronic diseases: the new epidemic

Mortality statistics show that there has been a significant change in the leading causes of death in Jamaica over the last 50 years, characterized by a decrease in the infectious diseases and those due to undernutrition and an increase in the non-communicable diseases. The various patterns of this epidemiological transition worldwide are outlined and the characteristics of this 'new' epidemic are discussed. Data are presented from the findings of the recent multi-country study of hypertension and diabetes, including Jamaica, which shows that as the body mass index (BMI) increases across the African diaspora, so does the prevalence of hypertension and diabetes. Among the Jamaican population studied, the prevalence of hypertension was 19.1among males and 28.2among females. Reported prevalence of previously diagnosed diabetes was 5.3in men and 10.4in females. The gender differences are in part explained by the differences in mean BMI which were 23.8 and 27.9, respectively, for males and females. 30.6of males and 64.7of females were either overweight or obese, with obesity prevalent in 7.2of the males and 31.5of the females studied. The increasing prevalence of obesity across the Caribbean is cause for concern as it significantly impacts on the demand for health and medical care. The identification of these reversible risk factors should be used to inform public policy to tackle what will be a growing concern.

Changes in red cell sodium content and blood pressure levels with potassiumplementation in black hypertensive patients

Red cell sodium and potassium content were measured in 24 hypertensive patients while they were hypokalaemic on thiazide diuretic therapy and agin after potassium supplements (48 meq elemental K+/day). Mean and diastolic blood levels fell by 4.1-4.4 and 44.5-5.2 mmHg respectively with potassium supplementation, while both urinary excretion of potassium and serum potassium rose. Urinary sodium excretion was unchanged. Red cell potassium remained within the normal range but red cell sodium, initially high, fell with potassium therapy. This study confirms the importance of potassium supplementation where hypokalaemia results from diuretic therapy