A Behavioral Intervention in a Cohort of Japanese-brazilians at High Cardiometabolic Risk

Intervenção comportamental em nipo-brasileiros com alto risco cardiometabólico ABSTRACT OBJECTIVE: To assess the effect of a health promotion program on cardiometabolic risk profi le in Japanese-Brazilians. METHODS: A total of 466 subjects from a study on diabetes prevalence conducted in the city of Bauru, southeastern Brazil, in 2000 completed a 1-year intervention program (2005-2006) based on healthy diet counseling and physical activity. Changes in blood pressure and metabolic parameters in the 2005-2006 period were compared with annual changes in these same variables in the 2000-2005 period. RESULTS: During the intervention, there were greater annual reductions in mean compared with the pre-intervention period. Signifi cant reductions in the prevalence of impaired fasting glucose/impaired glucose tolerance and diabetes were seen during the intervention (from 58. CONCLUSIONS: A one-year community-based health promotion program brings cardiometabolic benefi ts in a high-risk population of Japanese-Brazilians. Several trials have confi rmed that type 2 diabetes is preventable through intensive lifestyle interventions focusing on diet and physical activity among those with impaired glucose tolerance. Although the reduction in the incidence of diabetes assessed by annual glucose tolerance test was around 58%, the magnitude of changes in cardiovascular risk factors was more modest. Furthermore, glucose tolerance tests are unlikely to be a practical strategy to identify high-risk individuals and intensive lifestyle interventions such as those proposed in diabetes prevention trials are not widely available. The challenge is therefore to translate the fi ndings of diabetes prevention trials into strategies to reduce cardiometabolic risk in the general population. 19 One of the highest prevalence rates of diabetes worldwide have been reported in Japanese-Brazilians 5 who also have many other cardiovascular risk factors. 16 Cardiovascular disease was seen in 14% of this population 20 in 2000. Unhealthy diet and low physical activity have been the culprit risk factors for RESULTADOS: Durante a intervenção, foram observadas maiores reduções anuais médias (dp) na circunferência da cintura [


INTRODUCTION
increasing incidence rates of diabetes in several ethnic groups. 7High fat intake was associated with metabolic syndrome among Japanese-Brazilians in cross-sectional and longitudinal studies. 3,4The present study aimed to assess the effect of a 1-year community-based health promotion program in a population of Japanese-Brazilians by comparing their cardiometabolic profi le before and after the intervention.The study purposes and potential benefi ts of the behavioral intervention were outlined in invitation letters and telephone contacts.The 653 subjects who agreed to participate in the study had lower mean (SD) body mass index (BMI) [24.8 (3.7) vs. 25.2 (4.2) kg/m 2 , p<0.05] and higher systolic blood pressure [134.6 (25.6) vs. 130.0 (22.5) mmHg, p<0.05] in 2000 compared with non-subjects, but were otherwise similar.One year later, 466 remained in the intervention program and were reevaluated in 2006.Figure 1 illustrates the study design including causes of non-participation.Subjects who were lost to follow-up in 2006 had lower 2-hour plasma glucose levels in 2005 than those who were reevaluated [7.6 (2.9) vs. 8.2 (2.9) mmol/L, p<0.02], but all other demographic and clinical characteristics were similar.

Cross
The results of the 466 subjects who started the intervention in 2005 and remained in the program one year later are presented here.
The health promotion program targeted changes in dietary intake and levels and patterns of physical activity. 2It was based on World Health Organization (WHO) recommendation a and a previous trial conducted among overweight Brazilian adults. 17Over a 12-month period, each subject was offered one individual visit with a nutritionist, one group session on nutrition education, one group session for physical activity counseling, and two community exercise classes including walking, stretching, and dancing.Group sessions included 10 subjects and were coordinated by nutritionists and physical educators.The subjects' relatives were also invited to join the group sessions.
Dietary recommendations consisted of changes in total energy intake according to each individual's nutritional status; a list of food replacements was provided.The target proportions of macronutrients related to total energy intake were 50% to 60% of energy intake in carbohydrates; <30% in total fat; <10% in saturated fat; 10% to 15% in proteins; <300 mg of cholesterol and 15 g of vegetable fiber.Trained nutritionists monitored diet using 24-hour food recalls.Subjects were encouraged to engage in at least 30 minutes of physical activity per day.Compliance was estimated by the short version of the International Physical Activity Questionnaire.Physical educators and nutritionists reinforced the importance of adopting a healthy lifestyle and discussed the barriers to reaching the goals of the intervention program during the group sessions.Engagement in other physical activities opportunities was recommended.They did not receive any other counseling during the study period.They were instructed to maintain any previous medical treatment.Use of medications was taken into consideration in the statistical analysis.
Subjects underwent laboratory tests following standard multi-professional protocols in an outpatient clinic at baseline and after completing the 12-month intervention program.
Body weight and height were measured using calibrated electronic scales and a fi xed rigid stadiometer, respectively, while subjects wore light clothing without shoes.BMI was calculated as weight (kilograms) divided by squared height (meters).Waist circumference was measured with an inextensible tape according to the WHO technique.b Blood pressure was taken three times Fasting blood samples were taken and a 75-g oral glucose tolerance test was performed.Samples were immediately centrifuged and analyzed in a local laboratory.Plasma glucose was measured by the glucose-oxidase method and lipoproteins were determined enzymatically with an automatic analyzer.The American Diabetes Association criteria were used to categorize glucose tolerance status as diabetes, impaired fasting glucose (IFG) and impaired glucose tolerance (IGT). 1 All remaining samples were stored at -80 o C prior to hormone assay.Insulin was determined by immunometric assay using a quantitative chemiluminescent kit (Euro DPC Limited -Glyn Rhonwy, Llanberis, Caernarfon, Gwynedd, UK), with analytical sensitivity of 2.0 uIU/mL; intra-assay coeffi cient of variability ranged from 5.3% to 6.4% and the inter--assay coeffi cient of variability ranged from 5.9% to 8.0%.Insulin secretion was determined according to the homeostasis model assessment [HOMA- = 20 × fasting insulin (U/mL)/fasting glucose (mmol/L) -3.5]. 13The cardiovascular risk score was based on equations derived from the US Framingham cohort study. 6e  The differences in annual change were also estimated after stratifi cation by age (< 60 and ≥ 60 years old), generation (fi rst-and second-generation), gender and glucose tolerance status.Sensitivity analyses were conducted according to self-reported consumption of alcohol and use and/or change of medication (antihypertensives, lipid lowering and antidiabetic agents) that might infl uence outcomes.
All statistical analyses were performed using SPSS 12.0.
The Research Ethics Committee approved the study protocol (Protocol 1710, Of.COEP/151/08) and a written consent was obtained from all subjects.

RESULTS
The 466 subjects had a mean age of 55. 3   2, panel B).
There were signifi cantly greater improvements in the majority of cardiovascular risk factors post-intervention compared to the pre-intervention period, except for of diabetes in a high-risk population.Our fi ndings support the potential for lifestyle change in diabetes and cardiovascular disease prevention and are broadly consistent with results from previous studies of more intensive behavioral interventions among people with impaired glucose tolerance. 8,21A particular strength of our approach was the relatively low cost, both for identifi cation of high-risk individuals and the intervention, making it convenient in countries with limited resources for health.
In 2005 the study subjects were overweight and had a high waist circumference c considering their overall mean BMI (24.7 kg/m 2 ).Although the reductions in anthropometric parameters during the intervention were modest, statistically signifi cant and clinically relevant reductions were observed for blood pressure, plasma glucose, glucose tolerance, and total and LDL-cholesterol levels among those who enrolled in the community program.Similar fi ndings were reported in diabetes prevention studies among people with IGT.The Da Qing Study, Finnish Diabetes Prevention Study (DPS), and Diabetes Prevention Program showed that diabetes could be prevented by sustained lifestyle changes associated with modest weight loss. 8,14,21In the Indian Diabetes Prevention Program, there was a 26.4% reduction in the relative risk of progression to diabetes with almost no change in weight and waist circumference. 15An intensive lifestyle intervention among Japanese men was associated with a reduction in the incidence of diabetes greater than might be expected with a reduction in BMI, 10 suggesting that while weight loss may be desirable, it does not fully explain the effects of behavioral interventions.Longer follow-up of the Japanese-Brazilian subjects will provide more input concerning the potential for sustained effects on the risk of diabetes and persistence of cardiometabolic benefi ts.
A limitation of this study is that no control group was used for comparison during the intervention.Hence there is a possibility that the positive fi ndings may be due to confounding, regression to the mean or selection bias.The difference in changes in risk factors over the 5-year pre-intervention period compared with the 1-year intervention period does not rule out these potential explanations but does make them less likely.Data from this same population in the pre-intervention period works as a historical control, which means that this study used a plausibility design. 22This type of study is a feasible option for large scale interventions and provides valid evidence of impact. 22As for regression to the mean, if any, it would be similar in both periods studied.Since confounding factors that could produce these benefi ts on cardiometabolic profi le were not identifi ed, the results should be attributed to intervention HDL-cholesterol, triglycerides, and fasting insulin (Figure 3).
The magnitude, direction and statistical signifi cance of the results were unchanged when stratifi ed by gender, generation and age (data not shown).They were also unaffected when stratifi ed by prescribed medication and self-reported alcohol consumption (data not shown).effects.Although around half of those invited agreed to take part in the health promotion program, the characteristics of subjects and non-subjects were broadly similar, also suggesting that selection bias is not likely.There was no allocation concealment that increases the likelihood of bias in the outcome assessment.However, it is unlikely to affect laboratory tests and all study measures were taken according to standard operating procedures, and blood pressure was measured using automated equipment.The sensitivity analysis also suggests that the fi ndings are not due to changes in prescribed medication over time.The follow-up rate was reasonably good (71%).Those with missing data in 2006 were similar to those who underwent reevaluation except that they showed lower 2-hour plasma glucose levels.If subjects who were lost to follow-up had more severe risk factors then the benefi ts associated with the community program would be overestimated.

DISCUSSION
Although we may have underestimated the differences in annual change in risk factors between 2000 to 2005 and 2005 to 2006 as the fi rst period of observation was about more than fi ve times as long as the second one.
The effects of the health promotion program were not modifi ed by age, gender or generation; however, those with abnormal glucose metabolism in 2005 had greater decreases in plasma glucose during the intervention than those with normal glucose tolerance.The unexpected decrease in HDL-cholesterol (albeit remaining within the normal range) and increase in triglyceride levels persisted after sensitivity analyses.The changes in physical activity may not have been strong enough to induce an increase in HDL-cholesterol levels.Given the harmful effect of fat intake on cardiometabolic profi le in this population, as previously shown by our group, 3,4 the study dietary counseling strongly advocated a reduction in food consumption rich in fat.This could have resulted in a relative increase in carbohydrate intake which might have contributed to increased triglyceride levels. 18Analyses of self-reported physical activity and diet data may help better understand these fi ndings and possible mechanisms by which the intervention program appears to have produced benefi cial effects.
Fasting insulin levels increased post-intervention.As the HOMA-β was also higher after the intervention, it is possible that lifestyle changes were associated with improved beta cell function which was also refl ected in the benefi cial changes in metabolic parameters.
We do not know whether other discrete high-risk population subgroups would have the same uptake of, or response to, a health promotion program as seen among Japanese descendants.The benefi ts of the present program cannot be extrapolated to the entire Brazilian population or Asian immigrants living in other countries.We also cannot assure these changes will be sustained.Albeit more pronounced than in this study, evidence from the Finnish DPS shows that the benefi ts of behavioral interventions can persist following cessation of the intervention. 12It contrasts with the effect of risk reduction associated with the use of antidiabetic drugs which ceases when the medication is discontinued. 9It is also unclear whether improvements in proximal risk factors will translate into reductions in unfavorable health outcomes, although recent data from the long-term follow-up of the Da Qing Study looks promising. 11Follow-up of Japanese-Brazilian subjects may clarify whether changes in cardiometabolic risk factors will translate into the prevention of cardiovascular events.Furthermore, lifestyle changes which probably accounted for the observed improvements in risk factors might also be associated with reduced risk of other adverse health outcomes such as osteoporosis and some cancers.
A simple community-based behavioral counseling program over one year improved the cardiometabolic profi le in a high-risk population of Japanese-Brazilians. Obesity, diabetes, and their complications pose major public health challenges demanding responses at the population and individual level.Our fi ndings should encourage health care providers to promote a healthy diet and a physically active lifestyle among high-risk individuals and population subgroups.
-sectional study carried out with subjects from the Study on Diabetes and Associated Diseases in a Population of Japanese-Brazilians conducted in the city of Bauru, southeastern Brazil, in 2000. 5A total of 1,330 fi rst-(Japan-born) and second-generation (Brazilborn) Japanese-Brazilians of both genders participated in the previous cross-sectional study and were invited to join a community-based health promotion program commencing in 2005.a World Health Organization.Food and Agricultural Organization.The scientifi c basis for diet, nutrition and the prevention of type 2 diabetes.Geneva; 2003.b World Health Organization.Obesity: preventing and managing the global epidemic.Report of WHO Consultation on Obesity.Geneva; 1998.

Figure 1 .
Figure 1.Flowchart of subjects through each stage of the study.City of Bauru, southeastern Brazil, 2000, 2005 and 2006.

Figure 2 .
Figure 2. Standardized differences (and related 95% confi dence interval) of anthropometric and metabolic variables between 2005 and 2006 (panel A) and standardized differences in weight, fasting and 2-hour plasma glucose stratifi ed by glucose tolerance status in 2005 (panel B).City of Bauru, southeastern Brazil, 2005 and 2006.