Effect of baseline HbA1c level on the development of diabetes by lifestyle intervention in primary healthcare settings: insights from subanalysis of the Japan Diabetes Prevention Program

Dietary and other lifestyle factors and their influence on non-communicable diseases in the Western Pacific region

The Western Pacific region is a diverse region experiencing fast economic growth and nutrition transition. We systematically examined 94 cohort studies on the associations of dietary and other lifestyle factors on non-communicable diseases (NCDs) in the region. These studies were mainly from China, Japan, the Republic of Korea, and Singapore. Patterns and changes in lifestyle risk factors for NCDs based on national surveys were examined. They showed some dietary intake improvements over the past three decades, featured as increased consumption of unsaturated oils, fruits, and vegetables, and decreased consumption of sodium and unhealthy fat. Despite a decrease in smoking rate and salt intake, the values remained higher than the global levels in 2019. The ultra-processed food intake in the region increased at a higher rate than the global estimate. National guidelines relevant to NCDs in five selected countries were highlighted. Strong future actions and policies are needed to tackle NCDs.

Impact of individual and environmental factors on dietary or lifestyle interventions to prevent type 2 diabetes development: a systematic review

BACKGROUND

The variability in the effectiveness of type 2 diabetes (T2D) preventive interventions highlights the potential to identify the factors that determine treatment responses and those that would benefit the most from a given intervention. We conducted a systematic review to synthesize the evidence to support whether sociodemographic, clinical, behavioral, and molecular factors modify the efficacy of dietary or lifestyle interventions to prevent T2D.

METHODS

We searched MEDLINE, Embase, and Cochrane databases for studies reporting on the effect of a lifestyle, dietary pattern, or dietary supplement interventions on the incidence of T2D and reporting the results stratified by any effect modifier. We extracted relevant statistical findings and qualitatively synthesized the evidence for each modifier based on the direction of findings reported in available studies. We used the Diabetes Canada Clinical Practice Scale to assess the certainty of the evidence for a given effect modifier.

RESULTS

The 81 publications that met our criteria for inclusion are from 33 unique trials. The evidence is low to very low to attribute variability in intervention effectiveness to individual characteristics such as age, sex, BMI, race/ethnicity, socioeconomic status, baseline behavioral factors, or genetic predisposition.

CONCLUSIONS

We report evidence, albeit low certainty, that those with poorer health status, particularly those with prediabetes at baseline, tend to benefit more from T2D prevention strategies compared to healthier counterparts. Our synthesis highlights the need for purposefully designed clinical trials to inform whether individual factors influence the success of T2D prevention strategies.

Role of sociodemographic, clinical, behavioral, and molecular factors in precision prevention of type 2 diabetes: a systematic review

The variability in the effectiveness of type 2 diabetes (T2D) preventive interventions highlights the potential to identify the factors that determine treatment responses and those that would benefit the most from a given intervention. We conducted a systematic review to synthesize the evidence to support whether sociodemographic, clinical, behavioral, and molecular characteristics modify the efficacy of dietary or lifestyle interventions to prevent T2D. Among the 80 publications that met our criteria for inclusion, the evidence was low to very low to attribute variability in intervention effectiveness to individual characteristics such as age, sex, BMI, race/ethnicity, socioeconomic status, baseline behavioral factors, or genetic predisposition. We found evidence, albeit low certainty, to support conclusions that those with poorer health status, particularly those with prediabetes at baseline, tend to benefit more from T2D prevention strategies compared to healthier counterparts. Our synthesis highlights the need for purposefully designed clinical trials to inform whether individual factors influence the success of T2D prevention strategies.

Ethnic differences in response to lifestyle intervention for the prevention of type 2 diabetes in adults: A systematic review and meta-analysis

The risk of type 2 diabetes mellitus (T2DM) varies by ethnicity, but ethnic differences in response to diabetes prevention interventions remain unclear. This systematic review and meta-analysis assessed ethnic differences in the effects of lifestyle interventions on T2DM incidence, glycemic outcomes (fasting glucose, 2-h glucose, HbA_1c ), anthropometric measures (weight, BMI, waist circumference), and lifestyle behaviors (physical activity, energy intake, energy from fat, fiber intake). MEDLINE, EMBASE, and other databases were searched (to June 15, 2020) for randomized and non-randomized controlled trials on lifestyle interventions (diet and/or physical activity) in adults at risk of T2DM. Ethnicity was categorized into European, South Asian, East and Southeast Asian, Middle Eastern, Latin American, and African groups. Forty-four studies were included in meta-analyses. Overall, lifestyle interventions resulted in significant improvement in T2DM incidence, glycemic outcomes, anthropometric measures, physical activity, and energy intake (all P < 0.01). Significant subgroup differences by ethnicity were found for 2-h glucose, weight, BMI, and waist circumference (all P < 0.05) but not for T2DM incidence, fasting glucose, HbA_1c , and physical activity (all P > 0.05). Few studies in non-European groups reported dietary intake. Lifestyle interventions in different ethnic groups may have similar effects in reducing incidence of T2DM although this needs to be confirmed in further studies.

The Effect of Lifestyle Intervention on Diabetes Prevention by Ethnicity: A Systematic Review of Intervention Characteristics Using the TIDieR Framework

Lifestyle intervention is effective in preventing type 2 diabetes mellitus (T2DM), but the efficacy of intervention components across different ethnic groups is less clear. This systematic review examined the effects of intervention characteristics of lifestyle interventions on diabetes incidence and weight loss by ethnicity using the Template for Intervention Description and Replication (TIDieR) framework. MEDLINE, EMBASE and other databases were searched for randomized and non-randomized controlled trials on lifestyle interventions (diet and/or physical activity) in adults at risk of T2DM. Ethnicity was categorized into European, South Asian, East and Southeast Asian, Middle Eastern, Latin American and African groups. Forty-five studies (18,789 participants) were included in the systematic review and 41 studies in meta-analysis. Meta-analysis showed a high number of intervention sessions was significantly associated with a greater reduction in diabetes incidence (P = 0.043) and weight (P = 0.015), while other intervention characteristics including intervention provider and delivery format did not alter the outcomes (all P > 0.05). Additionally, narrative synthesis showed long-term interventions (≥12 months) were associated with significant diabetes risk reduction for all ethnic groups, while short-term interventions (<12 months) were more effective in weight loss in most ethnic groups. There may be ethnic preferences for the optimal number of intervention sessions.

Obtaining evidence base for the development of Feel4Diabetes intervention to prevent type 2 diabetes - a narrative literature review

BACKGROUND

Feel4Diabetes was a school and community based intervention aiming to promote healthy lifestyle and tackle obesity for the prevention of type 2 diabetes among families in 6 European countries. We conducted this literature review in order to guide the development of evidence-based implementation of the Feel4Diabetes intervention. We focused on type 2 diabetes prevention strategies, including all the phases from risk identification to implementation and maintenance. Special focus was given to prevention among vulnerable groups and people under 45 years.

METHODS

Scientific and grey literature published between January 2000 and January 2015 was searched for relevant studies using electronic databases. To present the literature review findings in a systematic way, we used the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework. A complementary literature search from February 2015 to December 2018 was also conducted.

RESULTS

The initial review included 27 studies with a follow-up ≥12 months and 9 studies with a follow-up ≥6 months and with a participant mean age < 45 years. We found out that interventions should be targeted at people at risk to improve recruiting and intervention effectiveness. Screening questionnaires (primarily Finnish Diabetes Risk Score FINDRISC) and blood glucose measurement can both be used for screening; the method does not appear to affect intervention effectiveness. Screening and recruitment is time-consuming, especially when targeting lower socioeconomic status and age under 45 years. The intervention intensity is more important for effectiveness than the mode of delivery. Moderate changes in several lifestyle habits lead to good intervention results. A minimum of 3-year follow-up seemed to be required to show a reduction in diabetes risk in high-risk individuals. In participants < 45 years, the achieved results in outcomes were less pronounced. The complementary review included 12 studies, with similar results regarding intervention targets and delivery modes, as well as clinical significance.

CONCLUSION

This narrative review highlighted several important aspects that subsequently guided the development of the Feel4Diabetes high-risk intervention. Research on diabetes prevention interventions targeted at younger adults or vulnerable population groups is still relatively scarce. Feel4Diabetes is a good example of a project aiming to fill this research gap.

TRIAL REGISTRATION

clinicaltrials.gov NCT02393872, registered 20th March 2015.

Diet, physical activity or both for prevention or delay of type 2 diabetes mellitus and its associated complications in people at increased risk of developing type 2 diabetes mellitus

BACKGROUND

The projected rise in the incidence of type 2 diabetes mellitus (T2DM) could develop into a substantial health problem worldwide. Whether diet, physical activity or both can prevent or delay T2DM and its associated complications in at-risk people is unknown.

OBJECTIVES

To assess the effects of diet, physical activity or both on the prevention or delay of T2DM and its associated complications in people at increased risk of developing T2DM.

SEARCH METHODS

This is an update of the Cochrane Review published in 2008. We searched the CENTRAL, MEDLINE, Embase, ClinicalTrials.gov, ICTRP Search Portal and reference lists of systematic reviews, articles and health technology assessment reports. The date of the last search of all databases was January 2017. We continuously used a MEDLINE email alert service to identify newly published studies using the same search strategy as described for MEDLINE up to September 2017.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) with a duration of two years or more.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodology for data collection and analysis. We assessed the overall quality of the evidence using GRADE.

MAIN RESULTS

We included 12 RCTs randomising 5238 people. One trial contributed 41% of all participants. The duration of the interventions varied from two to six years. We judged none of the included trials at low risk of bias for all 'Risk of bias' domains.Eleven trials compared diet plus physical activity with standard or no treatment. Nine RCTs included participants with impaired glucose tolerance (IGT), one RCT included participants with IGT, impaired fasting blood glucose (IFG) or both, and one RCT included people with fasting glucose levels between 5.3 to 6.9 mmol/L. A total of 12 deaths occurred in 2049 participants in the diet plus physical activity groups compared with 10 in 2050 participants in the comparator groups (RR 1.12, 95% CI 0.50 to 2.50; 95% prediction interval 0.44 to 2.88; 4099 participants, 10 trials; very low-quality evidence). The definition of T2DM incidence varied among the included trials. Altogether 315 of 2122 diet plus physical activity participants (14.8%) developed T2DM compared with 614 of 2389 comparator participants (25.7%) (RR 0.57, 95% CI 0.50 to 0.64; 95% prediction interval 0.50 to 0.65; 4511 participants, 11 trials; moderate-quality evidence). Two trials reported serious adverse events. In one trial no adverse events occurred. In the other trial one of 51 diet plus physical activity participants compared with none of 51 comparator participants experienced a serious adverse event (low-quality evidence). Cardiovascular mortality was rarely reported (four of 1626 diet plus physical activity participants and four of 1637 comparator participants (the RR ranged between 0.94 and 3.16; 3263 participants, 7 trials; very low-quality evidence). Only one trial reported that no non-fatal myocardial infarction or non-fatal stroke had occurred (low-quality evidence). Two trials reported that none of the participants had experienced hypoglycaemia. One trial investigated health-related quality of life in 2144 participants and noted that a minimal important difference between intervention groups was not reached (very low-quality evidence). Three trials evaluated costs of the interventions in 2755 participants. The largest trial of these reported an analysis of costs from the health system perspective and society perspective reflecting USD 31,500 and USD 51,600 per quality-adjusted life year (QALY) with diet plus physical activity, respectively (low-quality evidence). There were no data on blindness or end-stage renal disease.One trial compared a diet-only intervention with a physical-activity intervention or standard treatment. The participants had IGT. Three of 130 participants in the diet group compared with none of the 141 participants in the physical activity group died (very low-quality evidence). None of the participants died because of cardiovascular disease (very low-quality evidence). Altogether 57 of 130 diet participants (43.8%) compared with 58 of 141 physical activity participants (41.1%) group developed T2DM (very low-quality evidence). No adverse events were recorded (very low-quality evidence). There were no data on non-fatal myocardial infarction, non-fatal stroke, blindness, end-stage renal disease, health-related quality of life or socioeconomic effects.Two trials compared physical activity with standard treatment in 397 participants. One trial included participants with IGT, the other trial included participants with IGT, IFG or both. One trial reported that none of the 141 physical activity participants compared with three of 133 control participants died. The other trial reported that three of 84 physical activity participants and one of 39 control participants died (very low-quality evidence). In one trial T2DM developed in 58 of 141 physical activity participants (41.1%) compared with 90 of 133 control participants (67.7%). In the other trial 10 of 84 physical activity participants (11.9%) compared with seven of 39 control participants (18%) developed T2DM (very low-quality evidence). Serious adverse events were rarely reported (one trial noted no events, one trial described events in three of 66 physical activity participants compared with one of 39 control participants - very low-quality evidence). Only one trial reported on cardiovascular mortality (none of 274 participants died - very low-quality evidence). Non-fatal myocardial infarction or stroke were rarely observed in the one trial randomising 123 participants (very low-quality evidence). One trial reported that none of the participants in the trial experienced hypoglycaemia. One trial investigating health-related quality of life in 123 participants showed no substantial differences between intervention groups (very low-quality evidence). There were no data on blindness or socioeconomic effects.

AUTHORS' CONCLUSIONS

There is no firm evidence that diet alone or physical activity alone compared to standard treatment influences the risk of T2DM and especially its associated complications in people at increased risk of developing T2DM. However, diet plus physical activity reduces or delays the incidence of T2DM in people with IGT. Data are lacking for the effect of diet plus physical activity for people with intermediate hyperglycaemia defined by other glycaemic variables. Most RCTs did not investigate patient-important outcomes.

Diabetes prevention in the real world: Insights from the JDPP and J-DOIT1

Type 2 diabetes (T2D) is associated with increased risks of morbidity and mortality. Diabetes prevention is an urgent issue in Japan. The Finnish Diabetes Prevention Study and US Diabetes Prevention Program revealed that intensive lifestyle intervention can prevent or delay the development of T2D in high-risk populations. Translational research varies in hospitals, primary care, communities, the workplace, and other settings. Translational research is feasible but less effective. There have been no long-term follow-ups. The outcome of the studies was mainly weight changes. The Japan Diabetes Prevention Program (JDPP) is a trial to test the efficacy of a lifestyle intervention program, which carried out in a primary healthcare setting using existing resources. The Japan Diabetes Outcome Trial-1 (J-DOIT1) is a nationwide telephone-delivered lifestyle intervention in a real-world setting. This review will focus on the effectiveness of a diabetes prevention program (recruitment, target population, method of intervention, and evaluation) in the real world and insights from the JDPP and J-DOIT1.

Status Update on Translation of Integrated Primary Dental-Medical Care Delivery for Management of Diabetic Patients

Escalating prevalence of both diabetes and periodontal disease, two diseases associated with bi-directional exacerbation, has been reported. Periodontal disease represents a modifiable risk factor that may reduce diabetes onset or progression, and integrated models of cross-disciplinary care are needed to establish and manage glycemic control in affected patients. An ad-hoc environmental scan of current literature and media sought to characterize factors impacting status of integrated care models based on review of the existing evidence base in literature and media surrounding: (1) current cross-disciplinary practice patterns, (2) epidemiological updates, (3) status on risk assessment and screening for dysglycemia in the dental setting, (4) status on implementation of quality metrics for oral health, (5) care model pilots, and (6) public health perspectives. The survey revealed: escalating prevalence of diabetes and periodontitis globally; greater emphasis on oral health assessment for diabetic patients in recent medical clinical practice guidelines; high knowledgeability surrounding oral-systemic impacts on diabetes and growing receptivity to medical-dental integration among medical and dental providers; increasing numbers of programs/studies reporting on positive impact of emerging integrated dental-medical care models on diabetic patient healthcare access and health outcomes; a growing evidence base for clinically significant rates of undiagnosed dysglycemia among dental patients reported by point-of-care pilot studies; no current recommendation for population-based screening for dysglycemia in dental settings pending a stronger evidence base; improved definition of true periodontitis prevalence in (pre)/diabetics; emerging recognition of the need for oral health quality indicators and tracking; evidence of persistence in dental access disparity; updated status on barriers to integration. The potential benefit of creating clinically-applicable integrated care models to support holistic management of an escalating diabetic population by targeting modifiable risk factors including periodontitis is being recognized by the health industry. Cross-disciplinary efforts supported by high quality research are needed to mitigate previously- and newly-defined barriers of care integration and expedite development and implementation of integrated care models in various practice settings. Implementation of quality monitoring in the dental setting will support definition of the impact and efficacy of interventional clinical care models on patient outcomes.

Combined Diet and Physical Activity Promotion Programs to Prevent Type 2 Diabetes Among Persons at Increased Risk: A Systematic Review for the Community Preventive Services Task Force

BACKGROUND

Trials have shown efficacy of rigorous diet and physical activity promotion programs to reduce diabetes incidence and improve glycemic measures in adults at increased risk for type 2 diabetes.

PURPOSE

To evaluate diet and physical activity promotion programs for persons at increased risk for type 2 diabetes, primarily to reduce diabetes risk and decrease body weight and glycemia.

DATA SOURCES

MEDLINE, the Cochrane Central Register of Controlled Trials, CAB Abstracts, Global Health, and Ovid HealthSTAR from 1991 through 27 February 2015, with no language restriction.

STUDY SELECTION

8 researchers screened articles for single-group or comparative studies of combined diet and physical activity promotion programs with at least 2 sessions over at least 3 months in participants at increased risk for type 2 diabetes.

DATA EXTRACTION

7 researchers extracted data on study design; participant, intervention, and outcome descriptions; and results and assessed study quality.

DATA SYNTHESIS

53 studies (30 of diet and physical activity promotion programs vs. usual care, 13 of more intensive vs. less intensive programs, and 13 of single programs) evaluated 66 programs. Compared with usual care, diet and physical activity promotion programs reduced type 2 diabetes incidence (risk ratio [RR], 0.59 [95% CI, 0.52 to 0.66]) (16 studies), decreased body weight (net change, -2.2% [CI, -2.9% to -1.4%]) (24 studies) and fasting blood glucose level (net change, -0.12 mmol/L [-2.2 mg/dL] [CI, -0.20 to -0.05 mmol/L {-3.6 to -0.9 mg/dL}]) (17 studies), and improved other cardiometabolic risk factors. Evidence for clinical events was limited. More intensive programs were more effective.

LIMITATIONS

Wide variation in diet and physical activity promotion programs limited identification of features most relevant to effectiveness. Evidence on clinical outcomes and in children was sparse.

CONCLUSION

Combined diet and physical activity promotion programs are effective at decreasing diabetes incidence and improving cardiometabolic risk factors in persons at increased risk. More intensive programs are more effective.

PRIMARY FUNDING SOURCE

Centers for Disease Control and Prevention Community Preventive Services Task Force.