Community-based programmes achieved good results for most risk factors except BMI and ( glycated haemoglobin ) HbA1c .
INTRODUCTION Although cardiovascular disease ( CVD ) and type 2 diabetes mellitus ( T2DM ) prevention programmes have been effective in urban residents , their effectiveness in non-urban setting s , where cardio-metabolic risk is typically elevated , is unknown .
We systematic ally review ed the effectiveness of primary prevention programmes aim ed at reducing risk factors for CVD/T2DM , including blood pressure , body mass index ( BMI ) , blood lipid and glucose , diet , lifestyle , and knowledge in adults residing in non-urban areas .
Long-Term Weight Loss and Changes in Blood Pressure: Results of the Trials of Hypertension Prevention, Phase II
Approximately one fourth of the U.S. adult population nearly 50 million peoplehas hypertension ( 1 , 2 ) . Taking a broader perspective , more than half of the adult population has higher than optimal blood pressure ( 1 ) , defined as systolic blood pressure greater than 120 mm Hg and diastolic blood pressure greater than 80 mm Hg ( 2 ) . These persons are at significantly increased risk for cardiovascular disease and stroke ( 3 ) . Although pharmacologic treatment for hypertension significantly reduces morbidity and mortality from cardiovascular diseases ( 4 , 5 ) , long-term pharmacologic therapy can have undesirable side effects and requires the expense of continuing medical supervision . Furthermore , pharmacologic therapy is not usually initiated when blood pressure is higher than optimal yet below diagnostic thresholds for hypertension . Thus , lifestyle interventions for primary prevention and initial treatment of high blood pressure remain a vital strategy for controlling this highly prevalent condition ( 2 ) . Weight loss has been shown to reduce blood pressure in overweight hypertensive patients ( 6 - 9 ) and in overweight persons with high-normal blood pressure ( 10 - 12 ) . Two review s of r and omized trials of weight reduction to reduce blood pressure examined the results of nine studies ( 13 , 14 ) . Most of these trials were small , only one had more than 500 participants ( 11 ) , and most had short-term follow-up ( 1 year or less ) . Only three studies had follow-up of 3 to 5 years ( 8 , 10 , 11 ) . Compared with controls ,  weight loss  averaged nearly 7 kg in the short-term trials and approximately 3 kg in the three longer-term trials . In almost all trials , systolic blood pressure and diastolic blood pressure were reduced in the intervention groups . Since these review s were published , the Trials of Hypertension Prevention ( TOHP ) Phase I reported mean weight reduction of 3.9 kg at 18 months in 564 overweight participants with high-normal blood pressure , result ing in significant decreases in systolic blood pressure and diastolic blood pressure compared with a usual care control group ( 12 , 15 ) . To investigate whether nonpharmacologic interventions can prevent hypertension over the long term , TOHP II was initiated . This was a r and omized , controlled trial examining the effects of  weight loss and dietary sodium reduction , alone and in combination , in reducing blood pressure in overweight adults with high-normal diastolic blood pressure ( 16 ) . This target population is at high risk for hypertension as they age . The primary outcome paper from this trial ( 17 ) provided only a brief overview of the effects of weight loss on blood pressure . Here , we provide more detailed analysis of weight loss and blood pressure in TOHP II . Of special interest are the long-term effects of weight loss on blood pressure , the magnitude of the doseresponse relationship at 36 months , the effect of patterns of weight loss on blood pressure , and the predictors of weight loss and blood pressure response . Methods Participants Participants in TOHP II were overweight adults with nonmedicated diastolic blood pressure of 83 to 89 mm Hg and systolic blood pressure less than 140 mm Hg . Other eligibility criteria included age 30 to 54 years and a body mass index of 26.1 to 37.4 kg/m2 for men and 24.4 to 37.4 kg/m2 for women , approximately 110 % to 165 % of ideal weight ( 18 ) . Principal exclusion criteria were current treatment with medications that might affect blood pressure , clinical or laboratory evidence of cardiovascular disease , diabetes mellitus , renal insufficiency ( serum creatinine concentration 150 mol/L [ 1.7 mg/dL ] for men and 132 mol/L [ 1.5 mg/dL ] for women ) , and current or planned pregnancy . Detailed descriptions of recruitment and participant characteristics have been published elsewhere ( 19 , 20 ) . The study was review ed and approved by the institutional review boards at all nine TOHP centers and the coordinating center , and all participants signed informed consent forms . Design Eligible participants were r and omly assigned with equal probability to one of four groups : weight loss only , sodium reduction only , combined weight loss and sodium reduction , or usual care ( controls ) . Measurements Age , sex , ethnicity , and years of education were obtained by question naire . Baseline blood pressure measurements were taken at three screening visits , each separated by 7 to 45 days . At each visit , three readings of systolic blood pressure and diastolic blood pressure were obtained and averaged . Certified staff obtained measurements in seated participants by using a Hawksley r and om-zero sphygmomanometer ( 21 ) . Body weight was measured to the nearest 0.2 kg ( 0.5 lb ) by using a calibrated balance-beam scale ; participants wore indoor clothing ( without shoes ) . Blood pressure and weight were measured every 6 months after r and omization to the end of follow-up at 36 , 42 , or 48 months , depending on r and omization date . Clinic staff who were blinded to study group assignment made these assessment s. Blood pressure measurements were obtained during a single visit at all follow-up points except for 18 and 36 months , when measurements were taken at a series of three visits approximately 1 week apart . Multiple measurements were taken at 18 and 36 months to provide a more precise assessment of average blood pressures at these primary outcome points . Dietary intake was assessed by 24-hour recall , and physical activity was assessed by question naire . Intervention Participants assigned to the weight loss intervention group sought to lose at least 4.5 kg ( 10 lb ) during the first 6 months of the intervention and to maintain their weight loss for the remainder of the trial . A brief description of the intervention methods is presented here ; a more detailed description has been published elsewhere ( 22 ) . The intervention started with an individual counseling session , followed by 14 weekly group meetings led by dietitians or health educators . After this 14-week intensive phase , participants attended six biweekly group meetings and then monthly group meetings . Beginning in the 18th month , participants were offered a variety of options to keep them involved in the intervention , including individual counseling sessions and special group sessions focused on selected weight loss topics . The intervention focused on self-directed behavior change ( behavioral self-management ) , nutrition education , information on physical activity , and social support for making and maintaining behavior changes . Specific behavior change techniques included self-monitoring ( food diaries and graphs of minutes of physical activity per day ) , setting explicit short-term goals and developing specific action plans to achieve those objectives , and developing alternative strategies for situations that trigger problem eating . The dietary intervention focused on reducing caloric intake by decreasing consumption of excess fat , sugar , and alcohol . Keeping daily food diaries was emphasized for monitoring intake and assessing progress . With experience , the participants determined the caloric intake that produced moderate weight loss for them . It was suggested that men not consume less than 1500 kcal/d and women not less than 1200 kcal/d . Weight loss of more than 0.9 kg ( 2 lb ) per week was discouraged . The physical activity goal was to gradually increase activity to 30 to 45 minutes per day , four to five days per week . Exercise intensity was moderate , approximately 40 % to 55 % of heart rate reserve , and consisted primarily of brisk walking . Statistical Analysis Baseline characteristics of the weight loss and usual care groups were compared overall and by sex by using t-tests for means and chi-square tests for proportions . Although weight and blood pressure data were collected every 6 months , special efforts were made to achieve high follow-up rates at 18 and 36 months ; at each of these two time points , nine blood pressure readings were collected over three visits and were averaged . For participants prescribed antihypertensive medication , follow-up blood pressure for all subsequent visits was taken to be the last study blood pressure before therapy was started . Participants receiving medications that affect blood pressure for reasons other than hypertension or who became pregnant were treated as missing at that visit . We used two- sample t-tests to compare changes in weight and blood pressure from baseline in the  weight loss intervention and usual care groups overall , by sex , by ethnicity , and by sex and ethnicity . The effects of the intervention in terms of changes in weight and blood pressure were examined overall and in subgroups defined by sex , ethnicity , and sex and ethnicity . Subgroup differences were tested by using terms for the interaction of treatment group with sex and with ethnicity in multiple linear regression models . Regression analyses were also used to analyze the doseresponse relationship between change in weight and change in blood pressure , overall and within sex and ethnicity subgroups . Differences in dose response were tested by using interaction terms in linear regression models . All regressions were adjusted for age and baseline weight . We also adjusted for baseline blood pressure in the blood pressure regression models . Change in blood pressure was also examined in relation to quintile of weight loss . Quintiles were computed by using the distribution of weight change in the weight loss intervention group . Additional multiple regression analyses were performed in which weight loss participants were categorized according to patterns of weight loss at 6 and 36 months . The PROC MIXED function of SAS software ( SAS Institute , Inc. , Cary , North Carolina ) was used to perform repeated- measures analyses that tested differences over time by pattern of weight loss . Cox proportional-hazards models were used for survival analyses , with onset of hypertension as the outcome . Results Baseline Findings The baseline characteristics of participants assigned to
Community-based programmes achieved good results for most risk factors except BMI and ( glycated haemoglobin ) HbA1c .
INTRODUCTION Although cardiovascular disease ( CVD ) and type 2 diabetes mellitus ( T2DM ) prevention programmes have been effective in urban residents , their effectiveness in non-urban setting s , where cardio-metabolic risk is typically elevated , is unknown .
We systematic ally review ed the effectiveness of primary prevention programmes aim ed at reducing risk factors for CVD/T2DM , including blood pressure , body mass index ( BMI ) , blood lipid and glucose , diet , lifestyle , and knowledge in adults residing in non-urban areas .