Risk of Type 2 Diabetes Among Individuals with Excess Weight: Weight Trajectory Effects

PURPOSE OF REVIEW

Increased risk of type 2 diabetes mellitus (T2D) among individuals with overweight or obesity is well-established; however, questions remain about the temporal dynamics of weight change (gain or loss) on the natural course of T2D in this at-risk population. Existing epidemiologic evidence is limited to studies that discretely sample and assess excess weight and T2D risk at different ages with limited follow-up, yet changes in weight may have time-varying and possibly non-linear effects on T2D risk. Predicting the impact of weight change on the risk of T2D is key to informing primary prevention. We critically review the relationship between weight change, trajectory groups (i.e., distinct weight change patterns), and T2D risk among individuals with excess weight in recently published T2D prevention randomized controlled trials (RCTs) and longitudinal cohort studies.

RECENT FINDINGS

Overall, weight trajectory groups have been shown to differ by age of onset, sex, and patterns of insulin resistance or beta-cell function biomarkers. Lifestyle (diet and physical activity), pharmacological, and surgical interventions can modify an individual's weight trajectory. Adolescence is a critical etiologically relevant window during which onset of excess weight may be associated with higher risk of T2D. Changes in insulin resistance and beta-cell function biomarkers are distinct but related correlates of weight trajectory groups that evolve contemporaneously over time. These multi-trajectory markers are differentially associated with T2D risk. T2D risk may differ by the age of onset and duration of excess body weight, and the type of weight loss intervention. A better understanding of the changes in weight, insulin sensitivity, and beta-cell function as distinct but related correlates of T2D risk that evolve contemporaneously over time has important implications for designing and targeting primary prevention efforts.

Are interventions delivered by healthcare professionals effective for weight management? A systematic review of systematic reviews

OBJECTIVE

There are many systematic reviews of weight management interventions delivered by healthcare professionals (HCP), but it is not clear under what circumstances interventions are effective due to differences in review methodology. This review of systematic reviews synthesises the evidence about: (a) the effectiveness of HCP-delivered weight management interventions and (b) intervention and sample characteristics related to their effectiveness.

DESIGN

The review of reviews involved searching six databases (inception - October 2020). Reviews were included if they were (a) systematic, (b) weight management interventions delivered, at least partially, by HCP, (c) of randomised controlled trials and (d) written in English. Data regarding weight management outcomes (e.g. weight) and moderating factors were extracted. Secondary analyses were conducted using study-level data reported in each of the reviews.

SETTING

The review included studies that were delivered by HCP in any clinical or non-clinical setting.

PARTICIPANTS

Not applicable.

RESULTS

Six systematic reviews were included (forty-six unique studies). First-level synthesis showed that weight management interventions delivered by HCP are effective. The second-level synthesis found that interventions are only successful for up to 6 months, are most effective for women, non-Caucasians and adults and are most effective if they have at least six sessions.

CONCLUSIONS

As interventions are only successful for up to 6 months, they are not sufficient for achieving and maintaining a healthy weight.

Weight loss interventions in living donor liver transplantation as a tool in expanding the donor pool: A systematic review and meta-analysis

BACKGROUND

With increasing rates of liver transplantation and a stagnant donor pool, the annual wait list removals have remained high. Living donor liver transplantation (LDLT) is an established modality in expanding the donor pool and is the primary method of liver donation in large parts of the world. Marginal living donors, including those with hepatic steatosis, have been used to expand the donor pool. However, due to negative effects of steatosis on graft and recipient outcomes, current practice excludes overweight or obese donors with more than 10% macro vesicular steatosis. This has limited a potentially important source to help expand the donor pool. Weight loss is known to improve or resolve steatosis and rapid weight loss with short-term interventions have been used to convert marginal donors to low-risk donors in a small series of studies. There is, however, a lack of a consensus driven standardized approach to such interventions.

AIM

To assess the available data on using weight loss interventions in potential living liver donors with steatotic livers and investigated the feasibility, efficacy, and safety of using such donors on the donor, graft and recipient outcomes. The principal objective was to assess if using such treated donor livers, could help expand the donor pool.

METHODS

We performed a comprehensive literature review and meta-analysis on studies examining the role of short-term weight loss interventions in potential living liver donors with hepatic steatosis with the aim of increasing liver donation rates and improving donor, graft, and recipient outcomes.

RESULTS

A total of 6 studies with 102 potential donors were included. Most subjects were males (71). All studies showed a significant reduction in body mass index post-intervention with a mean difference of -2.08 (-3.06, 1.10, I² = 78%). A significant reduction or resolution of hepatic steatosis was seen in 93 of the 102 (91.2%). Comparison of pre- and post-intervention liver biopsies showed a significant reduction in steatosis with a mean difference of -21.22 (-27.02, -15.43, I² = 56%). The liver donation rates post-intervention was 88.5 (74.5, 95.3, I² = 42%). All donors who did not undergo LDLT had either recipient reasons or had fibrosis/steatohepatitis on post intervention biopsies. Post-operative biliary complications in the intervention group were not significantly different compared to controls with an odds ratio of 0.96 [(0.14, 6.69), I² = 0]. The overall post-operative donor, graft, and recipient outcomes in treated donors were not significantly different compared to donors with no steatosis.

CONCLUSION

Use of appropriate short term weight loss interventions in living liver donors is an effective tool in turning marginal donors to low-risk donors and therefore in expanding the donor pool. It is feasible and safe, with comparable donor, graft, and recipient outcomes, to non-obese donors. Larger future prospective studies are needed.

Effective recruitment for practice-based research: Lessons from the REAL HEALTH-Diabetes Study

Background

Aims: The REAL HEALTH Diabetes Study is a practice-based randomized clinical trial that compares the effectiveness of lifestyle intervention aimed at weight reduction to medical nutrition therapy in primary care patients with type 2 diabetes. This paper describes a tiered approach to recruitment, the resultant enrollment rates of sequentially more intensive recruitment strategies, and identifies barriers to participation.

Methods

Potential participants were identified using patient health registries and classified by recruitment site. Four recruitment strategies were used to achieve target enrollment: (1) mail/telephone outreach; (2) direct referral from providers; (3) orientation sessions; and (4) media/advertising. Reasons for ineligibility and non-participation were tracked.

Results

Fifteen thousand two hundred sixty-nine (15,269) potential participants were identified from all sources, with the clear majority coming from patient registries. Mail/telephone outreach alone had the lowest enrollment rate (1.2%). Direct referral and orientation sessions superimposed on mail/telephone outreach was used for fewer participants but had greater enrollment rates (27% and 52%.) Media/advertising was ineffective. The most commonly reported reasons for non-participation were not wanting to be in a research (30%) or a weight loss program (22%); time commitment (20%); and distance/transportation (14%).

Conclusions

The use of population registries to identify potential participants coupled with successively more intensive recruitment strategies, executed in a tiered approach moving toward personal engagement to establish trust and credibility, maximized recruitment enrollment rates. Our findings regarding facilitators and barriers to recruitment could be used to inform other practice-based research or to engage patients in group interventions in usual care settings.

Clinical trial registration

NCT02320253.

Energy restriction and Roux-en-Y gastric bypass reduce postprandial α-dicarbonyl stress in obese women with type 2 diabetes

AIMS/HYPOTHESIS

Dicarbonyl compounds are formed as byproducts of glycolysis and are key mediators of diabetic complications. However, evidence of postprandial α-dicarbonyl formation in humans is lacking, and interventions to reduce α-dicarbonyls have not yet been investigated. Therefore, we investigated postprandial α-dicarbonyl levels in obese women without and with type 2 diabetes. Furthermore, we evaluated whether a diet very low in energy (very low calorie diet [VLCD]) or Roux-en-Y gastric bypass (RYGB) reduces α-dicarbonyl stress in obese women with type 2 diabetes.

METHODS

In lean (n = 12) and obese women without (n = 27) or with type 2 diabetes (n = 27), we measured the α-dicarbonyls, methylglyoxal (MGO), glyoxal (GO) and 3-deoxyglucosone (3-DG), and glucose in fasting and postprandial plasma samples obtained during a mixed meal test. Obese women with type 2 diabetes underwent either a VLCD or RYGB. Three weeks after the intervention, individuals underwent a second mixed meal test.

RESULTS

Obese women with type 2 diabetes had higher fasting and particularly higher postprandial plasma α-dicarbonyl levels, compared with those without diabetes. After three weeks of a VLCD, postprandial α-dicarbonyl levels in diabetic women were significantly reduced (AUC MGO -14%, GO -16%, 3-DG -25%), mainly through reduction of fasting plasma α-dicarbonyls (MGO -13%, GO -13%, 3-DG -33%). Similar results were found after RYGB.

CONCLUSIONS/INTERPRETATION

This study shows that type 2 diabetes is characterised by increased fasting and postprandial plasma α-dicarbonyl stress, which can be reduced by improving glucose metabolism through a VLCD or RYGB. These data highlight the potential to reduce reactive α-dicarbonyls in obese individuals with type 2 diabetes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01167959.