Daily Endocrinology Research Analysis
Three studies advance endocrinology across nutrition and diabetes care: a comprehensive meta-analysis supports the Mediterranean diet for patients with existing metabolic diseases; a large NHANES cohort clarifies how diet quality and physical activity differentially relate to mortality in people with and without diabetes; and a double-blind crossover RCT in type 1 diabetes details patient-reported benefits and gastrointestinal trade-offs when adding semaglutide to automated insulin delivery.
Summary
Three studies advance endocrinology across nutrition and diabetes care: a comprehensive meta-analysis supports the Mediterranean diet for patients with existing metabolic diseases; a large NHANES cohort clarifies how diet quality and physical activity differentially relate to mortality in people with and without diabetes; and a double-blind crossover RCT in type 1 diabetes details patient-reported benefits and gastrointestinal trade-offs when adding semaglutide to automated insulin delivery.
Research Themes
- Precision nutrition for metabolic disease management
- Adjunct incretin therapy with automated insulin delivery in type 1 diabetes
- Diet quality and physical activity interactions with mortality by diabetes status
Selected Articles
1. Mediterranean diet for the management of pre-existing metabolic diseases: Evidence from a systematic review and meta-analysis featured in the Italian national guidelines "La Dieta Mediterranea".
This systematic review and meta-analysis of 69 studies shows that greater adherence to the Mediterranean diet in patients with existing metabolic diseases is associated with reduced all-cause mortality and modest improvements in key cardiometabolic risk markers. Evidence quality was generally moderate to low, with inconsistent effects on HDL, lean mass, and HbA1c.
Impact: Provides integrative evidence supporting the Mediterranean diet as a therapeutic strategy in patients with metabolic diseases, including a mortality signal in T2D/metabolic syndrome.
Clinical Implications: Clinicians can recommend Mediterranean diet patterns as part of comprehensive therapy for patients with metabolic diseases to achieve modest cardiometabolic improvements and potential mortality reduction, while prioritizing individualized counseling and long-term adherence.
Key Findings
- Higher Mediterranean diet adherence was associated with reduced all-cause mortality in type 2 diabetes or metabolic syndrome (RR 0.93; 95% CI 0.90–0.97).
- Moderate-quality evidence supported improvements in BMI, waist circumference, LDL cholesterol, triglycerides, fasting glucose, HOMA-IR, and C-reactive protein.
- Effects on HDL cholesterol, lean mass, and HbA1c were inconsistent; evidence on gut microbiota modulation was very limited.
Methodological Strengths
- PRISMA 2020 and MOOSE adherence with comprehensive database search up to Feb 2024
- Study quality and certainty explicitly appraised (Newcastle-Ottawa Scale, NUTRIGRADE) with random-effects pooling
Limitations
- Heterogeneity across populations, study designs, and outcome definitions; overall certainty moderate to low
- Limited data on patient-centered outcomes (quality of life reported in only one RCT) and on gut microbiota
Future Directions: Conduct long-term, high-quality RCTs in patients with specific metabolic diseases to quantify effects on hard outcomes (mortality, cardiovascular events) and to assess mechanistic links including gut microbiota.
BACKGROUND: Metabolic diseases such as obesity, type 2 diabetes mellitus, metabolic syndrome, dyslipidemia, and non-alcoholic fatty liver disease are major contributors to cardiometabolic risk. While the Mediterranean diet (MD) is well-established in primary prevention, its role in individuals with pre-existing metabolic conditions remains less defined. METHODS: A systematic review and meta-analysis were conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 2020 and Meta-analysis of Observational Studies in Epidemiology guidelines. PubMed, Scopus, Embase, and Cochrane Library were searched through February 2024. Study quality was assessed using the Newcastle-Ottawa Scale; evidence certainty was evaluated with the NUTRIGRADE tool. Random-effects models were used to pool effect sizes. RESULTS: Sixty-nine studies were included. Higher adherence to the MD was associated with reduced all-cause mortality in individuals with type 2 diabetes or metabolic syndrome (risk ratios: 0.93; 95% CI: 0.90-0.97). Moderate-quality evidence supported improvements in BMI, waist circumference, LDL cholesterol, triglycerides, fasting glucose, HOMA-IR, and C-reactive protein. Findings for HDL cholesterol, lean mass, and HbA1c were inconsistent. One RCT reported improved quality of life, while evidence on gut microbiota modulation remains very limited and largely descriptive. Overall, evidence certainty ranged from moderate to low. CONCLUSIONS: Greater adherence to the MD is linked to modest but clinically relevant improvements in metabolic health and reduced mortality in individuals with existing metabolic diseases. These findings support its inclusion in therapeutic dietary strategies, though further high-quality, long-term trials are needed to inform clinical guidelines.
2. Semaglutide use with automated insulin delivery in adults with type 1 diabetes: qualitative analyses and patient-reported outcomes from a randomized controlled trial.
In a double-blind crossover RCT of adults with type 1 diabetes using automated insulin delivery, semaglutide increased gastrointestinal symptoms on the DBSQ but did not produce clear differences on other patient-reported outcomes compared with placebo. Qualitative interviews revealed high patient interest due to perceived benefits (lower insulin, weight loss, better glycemia) and a sense of synergy with automated insulin delivery, while nausea impeded accurate pre-meal bolusing.
Impact: Offers patient-centered evidence on the lived experience and trade-offs of adjunct semaglutide with automated insulin delivery in type 1 diabetes within a blinded RCT framework.
Clinical Implications: If considering off-label semaglutide with automated insulin delivery in type 1 diabetes, clinicians should proactively manage gastrointestinal side effects and reinforce safe pre-meal bolus strategies during titration to maintain glycemic control.
Key Findings
- Only the Diabetes Bowel Symptom Questionnaire differentiated semaglutide from placebo, showing increased gastrointestinal symptom frequency and severity with semaglutide.
- In interviews, 42% of participants expressed interest in using semaglutide outside the trial, citing lower insulin needs, weight loss, and improved glycemic control; participants noted synergy with automated insulin delivery.
- Nausea and fear of vomiting impeded accurate pre-meal carbohydrate estimation and bolusing during semaglutide use.
Methodological Strengths
- Double-blind randomized cross-over design with standardized automated insulin delivery
- Mixed-methods approach combining validated PRO instruments and inductive–deductive thematic qualitative analysis
Limitations
- Small sample size limits power to detect differences across PROs
- Short intervention periods and focus on patient-reported outcomes without hard clinical endpoints
Future Directions: Larger, longer RCTs should assess glycemic endpoints, hypoglycemia, time-in-range, and adherence when combining semaglutide with automated insulin delivery, and test strategies to mitigate gastrointestinal side effects.
BACKGROUND: Interest in incretin therapy for type 1 diabetes is increasing, but data lacks regarding patient-reported outcomes and personal experience in this population with this drug. METHODS: This is an analysis from a double-blinded randomized cross-over trial assessing semaglutide vs. placebo, with automated insulin delivery in adults with type 1 diabetes, after 15-week interventions. The following questionnaires were performed after each intervention: Diabetes Distress Scale, Hypoglycemia Fear Survey, Diabetes Treatment Satisfaction Questionnaire, INSPIRE, and Diabetes Bowel Symptom Questionnaire (DBSQ). Semi-structured interviews were performed at the end of the trial. Interviews were recorded, transcribed, and coded by research personnel for themes using an inductive-deductive approach. RESULTS: Twenty-three participants completed questionnaires, while 24 performed interviews. For semaglutide vs. placebo, only the DBSQ showed differing scores with increased symptom frequency and severity with semaglutide. Within the interviews, 42% expressed their interested in semaglutide use outside the study, with reasons being lower insulin requirements, weight loss, and improved glycemic control. Many of these qualities, including complication risk reduction, were qualities of the ideal adjunctive therapy as per participants. Nausea and fear of vomiting were barriers to accurate pre-meal determination of upcoming carbohydrate intake and thus pre-meal bolus. Synergy was noted between the drug and automated insulin delivery by the participants. CONCLUSIONS: Semaglutide is of interest to those with type 1 diabetes. Safe and accurate bolus practice by patients in the context of nausea should be reviewed during dose titration. Questionnaires did not capture differences between semaglutide and placebo outside of increased gastrointestinal side effects. (Clinicaltrials.gov number NCT05205928).
3. Joint association of diet quality scores and physical activity status with all-cause mortality among individuals with and without diabetes.
In 20,002 NHANES participants, sufficient physical activity and high diet quality were jointly associated with lower all-cause mortality. In diabetes, mortality reduction was primarily attributable to physical activity rather than diet alone, whereas in non-diabetes, higher diet quality (MED or HEI-2020) alone reduced risk; DASH adherence showed no significant associations.
Impact: Clarifies differential contributions of diet quality and physical activity to mortality risk by diabetes status, informing targeted lifestyle recommendations.
Clinical Implications: For people with diabetes, prioritize achieving sufficient physical activity as a mortality risk reduction strategy, while in those without diabetes, emphasize improving diet quality (e.g., MED, HEI-2020); combine both for maximal benefit.
Key Findings
- High diet quality and sufficient physical activity were associated with lower all-cause mortality (e.g., DII HR: diabetes 0.39; non-diabetes 0.52).
- In diabetes, mortality reduction was linked to physical activity (PAF ~2.70–2.73%) rather than diet alone.
- In non-diabetes, MED or HEI-2020 diets alone reduced mortality risk by approximately 16.08–21.52%; DASHI showed no significant association.
Methodological Strengths
- Large, nationally representative sample with adjusted Cox models
- Use of multiple diet quality indices and estimation of population attributable fractions
Limitations
- Observational design with potential residual confounding and measurement error in self-reported diet/PA
- Follow-up duration not specified in the abstract; causality cannot be inferred
Future Directions: Prospective interventions should test combined diet quality enhancement and physical activity promotion, stratified by diabetes status, and assess hard outcomes with device-based PA measures.
OBJECTIVE: To examine the effects and differences in the association between multiple dietary patterns and physical activity (PA) with all-cause mortality in individuals with and without diabetes. METHOD: The analysis included 20,002 participants from NHANES. Cox proportional hazards regression was used to analysis the relationship between diet quality scores and PA with mortality. The population attributable fraction (PAF) was used to estimate the proportion of deaths which could be avoided. RESULTS: Adjusted hazard ratios for mortality with high diet quality and sufficient PA were as follows: dietary inflammatory index (DII) (diabetes: 0.39, p = 0.021; without diabetes: 0.52, p = 0.007), Mediterranean Diet Score (MED) (diabetes: 0.56, p = 0.071; without diabetes: 0.51, p = 0.004), and Healthy eating index-2020 (HEI-2020) (diabetes: 0.45, p = 0.041; without diabetes: 0.41, p = 0.001). In diabetes, 2.70 %-2.73 % lower mortality was linked to PA, not diet alone. Without diabetes, MED or HEI-2020 diets alone reduced the risk by 16.08 %-21.52 %, not PA alone. The Dietary Approaches to Stop Hypertension Index (DASHI) showed no significant association with mortality in participants with or without diabetes (p = 0.260, 0.199). CONCLUSION: High diet quality alone was associated with lower risk of mortality in people without diabetes, while it did not show a significant association with diabetes. PA by itself did correlate with lower mortality risk among diabetes.