ABSTRACT
AIMS/HYPOTHESIS: To provide a systematic overview of the current body of evidence on high-risk phenotypes of diabetes associated with COVID-19 severity and death. METHODS: This is the first update of our recently published living systematic review and meta-analysis. Observational studies investigating phenotypes in individuals with diabetes and confirmed SARS-CoV-2 infection with regard to COVID-19-related death and severity were included. The literature search was conducted from inception up to 14 February 2022 in PubMed, Epistemonikos, Web of Science and the COVID-19 Research Database and updated using PubMed alert to 1 December 2022. A random-effects meta-analysis was used to calculate summary relative risks (SRRs) with 95% CIs. The risk of bias was evaluated using the Quality in Prognosis Studies (QUIPS) tool and the certainty of evidence using the GRADE approach. RESULTS: A total of 169 articles (147 new studies) based on approximately 900,000 individuals were included. We conducted 177 meta-analyses (83 on COVID-19-related death and 94 on COVID-19 severity). Certainty of evidence was strengthened for associations between male sex, older age, blood glucose level at admission, chronic insulin use, chronic metformin use (inversely) and pre-existing comorbidities (CVD, chronic kidney disease, chronic obstructive pulmonary disease) and COVID-19-related death. New evidence with moderate to high certainty emerged for the association between obesity (SRR [95% CI] 1.18 [1.04, 1.34], n=21 studies), HbA1c (53-75 mmol/mol [7-9%]: 1.18 [1.06, 1.32], n=8), chronic glucagon-like peptide-1 receptor agonist use (0.83 [0.71, 0.97], n=9), pre-existing heart failure (1.33 [1.21, 1.47], n=14), pre-existing liver disease (1.40 [1.17, 1.67], n=6), the Charlson index (per 1 unit increase: 1.33 [1.13, 1.57], n=2), high levels of C-reactive protein (per 5 mg/l increase: 1.07 [1.02, 1.12], n=10), aspartate aminotransferase level (per 5 U/l increase: 1.28 [1.06, 1.54], n=5), eGFR (per 10 ml/min per 1.73 m2 increase: 0.80 [0.71, 0.90], n=6), lactate dehydrogenase level (per 10 U/l increase: 1.03 [1.01, 1.04], n=7) and lymphocyte count (per 1×109/l increase: 0.59 [0.40, 0.86], n=6) and COVID-19-related death. Similar associations were observed between risk phenotypes of diabetes and severity of COVID-19, with some new evidence on existing COVID-19 vaccination status (0.32 [0.26, 0.38], n=3), pre-existing hypertension (1.23 [1.14, 1.33], n=49), neuropathy and cancer, and high IL-6 levels. A limitation of this study is that the included studies are observational in nature and residual or unmeasured confounding cannot be ruled out. CONCLUSIONS/INTERPRETATION: Individuals with a more severe course of diabetes and pre-existing comorbidities had a poorer prognosis of COVID-19 than individuals with a milder course of the disease. REGISTRATION: PROSPERO registration no. CRD42020193692. PREVIOUS VERSION: This is a living systematic review and meta-analysis. The previous version can be found at https://link.springer.com/article/10.1007/s00125-021-05458-8 FUNDING: The German Diabetes Center (DDZ) is funded by the German Federal Ministry of Health and the Ministry of Culture and Science of the State North Rhine-Westphalia. This study was supported in part by a grant from the German Federal Ministry of Education and Research to the German Center for Diabetes Research (DZD).
Subject(s)
COVID-19 , Diabetes Mellitus , Male , Humans , SARS-CoV-2 , Prognosis , Phenotype , Observational Studies as TopicABSTRACT
BACKGROUND: There is growing evidence that substituting animal-based with plant-based foods is associated with a lower risk of cardiovascular diseases (CVD), type 2 diabetes (T2D), and all-cause mortality. Our aim was to summarize and evaluate the evidence for the substitution of any animal-based foods with plant-based foods on cardiometabolic health and all-cause mortality in a systematic review and meta-analysis. METHODS: We systematically searched MEDLINE, Embase, and Web of Science to March 2023 for prospective studies investigating the substitution of animal-based with plant-based foods on CVD, T2D, and all-cause mortality. We calculated summary hazard ratios (SHRs) and 95% confidence intervals (95% CI) using random-effects meta-analyses. We assessed the certainty of evidence (CoE) using the GRADE approach. RESULTS: In total, 37 publications based on 24 cohorts were included. There was moderate CoE for a lower risk of CVD when substituting processed meat with nuts [SHR (95% CI): 0.73 (0.59, 0.91), n = 8 cohorts], legumes [0.77 (0.68, 0.87), n = 8], and whole grains [0.64 (0.54, 0.75), n = 7], as well as eggs with nuts [0.83 (0.78, 0.89), n = 8] and butter with olive oil [0.96 (0.95, 0.98), n = 3]. Furthermore, we found moderate CoE for an inverse association with T2D incidence when substituting red meat with whole grains/cereals [0.90 (0.84, 0.96), n = 6] and red meat or processed meat with nuts [0.92 (0.90, 0.94), n = 6 or 0.78 (0.69, 0.88), n = 6], as well as for replacing poultry with whole grains [0.87 (0.83, 0.90), n = 2] and eggs with nuts or whole grains [0.82 (0.79, 0.86), n = 2 or 0.79 (0.76, 0.83), n = 2]. Moreover, replacing red meat for nuts [0.93 (0.91, 0.95), n = 9] and whole grains [0.96 (0.95, 0.98), n = 3], processed meat with nuts [0.79 (0.71, 0.88), n = 9] and legumes [0.91 (0.85, 0.98), n = 9], dairy with nuts [0.94 (0.91, 0.97), n = 3], and eggs with nuts [0.85 (0.82, 0.89), n = 8] and legumes [0.90 (0.89, 0.91), n = 7] was associated with a reduced risk of all-cause mortality. CONCLUSIONS: Our findings indicate that a shift from animal-based (e.g., red and processed meat, eggs, dairy, poultry, butter) to plant-based (e.g., nuts, legumes, whole grains, olive oil) foods is beneficially associated with cardiometabolic health and all-cause mortality.
Subject(s)
Cardiovascular Diseases , Diabetes Mellitus, Type 2 , Humans , Animals , Diet , Prospective Studies , Diabetes Mellitus, Type 2/epidemiology , Olive Oil , Vegetables , Meat , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/prevention & control , Cardiovascular Diseases/complications , Butter , Risk FactorsABSTRACT
To summarize and evaluate the evidence on the health impact of a vegan diet, we conducted an umbrella review of systematic reviews and meta-analyses. PubMed, Cochrane Library, Web of Science and Epistemonikos were searched up to September 2021. Meta-analyses were recalculated by using a random effects model. The certainty of evidence (CoE) was evaluated by the GRADE approach. For the general healthy population, a vegan diet was effective for reducing body weight [MD (95% CI): -2.52 kg (-3.06, -1.98), n = 8 RCTs; moderate CoE] and was associated with further health benefits (with low CoE), including a lower risk of cancer incidence [SRR (95% CI): 0.84 (0.75, 0.95), n = 2] and a trend for lower risk of all-cause mortality [SRR (95% CI): 0.87 (0.75, 1.01), n = 2], as well as lower ApoB levels [MD (95% CI): -0.19 µmol/L (-0.23, -0.15), n = 7 RCTs). The findings suggested adverse associations for a vegan diet with risk of fractures [SRR (95% CI): 1.46 (1.03, 2.07), n = 3; low CoE]. For persons with diabetes or at high CVD risk, a vegan diet reduced measures of adiposity, total cholesterol, LDL and improved glycemic control (CoE moderate to low). A vegan diet may have the potential for the prevention of cardiometabolic health, but it may also impair bone health. More well-conducted primary studies are warranted.
Subject(s)
Diet, Vegan , Neoplasms , Humans , Systematic Reviews as Topic , Body Weight , Neoplasms/prevention & control , Risk AssessmentABSTRACT
AIMS/HYPOTHESIS: The term prediabetes is used for individuals who have impaired glucose metabolism whose glucose or HbA1c levels are not yet high enough to be diagnosed as diabetes. Prediabetes may already be associated with an increased risk of chronic 'diabetes-related' complications. This umbrella review aimed to provide a systematic overview of the available evidence from meta-analyses of prospective observational studies on the associations between prediabetes and incident diabetes-related complications in adults and to evaluate their strength and certainty. METHODS: For this umbrella review, systematic reviews with meta-analyses reporting summary risk estimates for the associations between prediabetes (based on fasting or 2 h postload glucose or on HbA1c) and incidence of diabetes-related complications, comorbidities and mortality risk were included. PubMed, Web of Science, the Cochrane Library and Epistemonikos were searched up to 17 June 2021. Summary risk estimates were recalculated using a random effects model. The certainty of evidence was evaluated by applying the GRADE tool. This study is registered with PROSPERO, CRD42020153227. RESULTS: Ninety-five meta-analyses from 16 publications were identified. In the general population, prediabetes was associated with a 6-101% increased risk for all-cause mortality and the incidence of cardiovascular outcomes, CHD, stroke, heart failure, atrial fibrillation and chronic kidney disease, as well as total cancer, total liver cancer, hepatocellular carcinoma, breast cancer and all-cause dementia with moderate certainty of evidence. No associations between prediabetes and incident depressive symptoms and cognitive impairment were observed (with low or very low certainty of evidence). The association with all-cause mortality was stronger for prediabetes defined by impaired glucose tolerance than for prediabetes defined by HbA1c. CONCLUSIONS/INTERPRETATION: Prediabetes was positively associated with risk of all-cause mortality and the incidence of cardiovascular outcomes, CHD, stroke, chronic kidney disease, cancer and dementia. Further high-quality studies, particularly on HbA1c-defined prediabetes and other relevant health outcomes (e. g. neuropathy) are required to support the evidence.
Subject(s)
Diabetes Complications/mortality , Prediabetic State/mortality , Cardiovascular Diseases/mortality , Cause of Death , Dementia/mortality , Glucose Intolerance/complications , Humans , Kidney Diseases/mortality , Neoplasms/mortality , Risk FactorsABSTRACT
AIMS/HYPOTHESIS: Diabetes has been identified as a risk factor for poor prognosis of coronavirus disease-2019 (COVID-19). The aim of this study is to identify high-risk phenotypes of diabetes associated with COVID-19 severity and death. METHODS: This is the first edition of a living systematic review and meta-analysis on observational studies investigating phenotypes in individuals with diabetes and COVID-19-related death and severity. Four different databases were searched up to 10 October 2020. We used a random effects meta-analysis to calculate summary relative risks (SRR) with 95% CI. The certainty of evidence was evaluated by the GRADE tool. RESULTS: A total of 22 articles, including 17,687 individuals, met our inclusion criteria. For COVID-19-related death among individuals with diabetes and COVID-19, there was high to moderate certainty of evidence for associations (SRR [95% CI]) between male sex (1.28 [1.02, 1.61], n = 10 studies), older age (>65 years: 3.49 [1.82, 6.69], n = 6 studies), pre-existing comorbidities (cardiovascular disease: 1.56 [1.09, 2.24], n = 8 studies; chronic kidney disease: 1.93 [1.28, 2.90], n = 6 studies; chronic obstructive pulmonary disease: 1.40 [1.21, 1.62], n = 5 studies), diabetes treatment (insulin use: 1.75 [1.01, 3.03], n = 5 studies; metformin use: 0.50 [0.28, 0.90], n = 4 studies) and blood glucose at admission (≥11 mmol/l: 8.60 [2.25, 32.83], n = 2 studies). Similar, but generally weaker and less precise associations were observed between risk phenotypes of diabetes and severity of COVID-19. CONCLUSIONS/INTERPRETATION: Individuals with a more severe course of diabetes have a poorer prognosis of COVID-19 compared with individuals with a milder course of disease. To further strengthen the evidence, more studies on this topic that account for potential confounders are warranted. REGISTRATION: PROSPERO registration ID CRD42020193692.
Subject(s)
COVID-19/diagnosis , COVID-19/mortality , Diabetes Mellitus , Aged , Aged, 80 and over , COVID-19/complications , COVID-19/therapy , Comorbidity , Diabetes Complications/diagnosis , Diabetes Complications/mortality , Diabetes Complications/pathology , Diabetes Complications/therapy , Diabetes Mellitus/diagnosis , Diabetes Mellitus/mortality , Diabetes Mellitus/therapy , Female , Humans , Male , Middle Aged , Mortality , Phenotype , Prognosis , Respiration, Artificial , Risk Factors , SARS-CoV-2/physiology , Severity of Illness Index , Treatment OutcomeABSTRACT
BACKGROUND: The role of fat quantity and quality in type 2 diabetes (T2D) prevention is controversial. Thus, this systematic review and meta-analysis aimed to investigate the associations between intake of dietary fat and fatty acids and T2D, and to evaluate the certainty of evidence. METHODS AND FINDINGS: We systematically searched PubMed and Web of Science through 28 October 2019 for prospective observational studies in adults on the associations between intake of dietary fat and fatty acids and T2D incidence. The systematic literature search and data extraction were conducted independently by 2 researchers. We conducted linear and nonlinear random effects dose-response meta-analyses, calculated summary relative risks (SRRs) with their corresponding 95% confidence intervals (95% CIs), and assessed the certainty of evidence. In total, 15,070 publications were identified in the literature search after the removal of duplicates. Out of the 180 articles screened in full text, 23 studies (19 cohorts) met our inclusion criteria, with 11 studies (6 cohorts) conducted in the US, 7 studies (7 cohorts) in Europe, 4 studies (5 cohorts) in Asia, and 1 study (1 cohort) in Australia. We mainly observed no or weak linear associations between dietary fats and fatty acids and T2D incidence. In nonlinear dose-response meta-analyses, the protective association for vegetable fat and T2D was steeper at lower levels up to 13 g/d (SRR [95% CI]: 0.81 [0.76; 0.88], pnonlinearity = 0.012, n = 5 studies) than at higher levels. Saturated fatty acids showed an apparent protective association above intakes around 17 g/d with T2D (SRR [95% CI]: 0.95 [0.90; 1.00], pnonlinearity = 0.028, n = 11). There was a nonsignificant association of a decrease in T2D incidence for polyunsaturated fatty acid intakes up to 5 g/d (SRR [95% CI]: 0.96 [0.91; 1.01], pnonlinearity = 0.023, n = 8), and for alpha-linolenic acid consumption up to 560 mg/d (SRR [95% CI]: 0.95 [0.90; 1.00], pnonlinearity = 0.014, n = 11), after which the curve rose slightly, remaining close to no association. The association for long-chain omega-3 fatty acids and T2D was approximately linear for intakes up to 270 mg/d (SRR [95% CI]: 1.10 [1.06; 1.15], pnonlinearity < 0.001, n = 16), with a flattening curve thereafter. Certainty of evidence was very low to moderate. Limitations of the study are the high unexplained inconsistency between studies, the measurement of intake of dietary fats and fatty acids via self-report on a food group level, which is likely to lead to measurement errors, and the possible influence of unmeasured confounders on the findings. CONCLUSIONS: There was no association between total fat intake and the incidence of T2D. However, for specific fats and fatty acids, dose-response curves provided insights for significant associations with T2D. In particular, a high intake of vegetable fat was inversely associated with T2D incidence. Thus, a diet including vegetable fat rather than animal fat might be beneficial regarding T2D prevention.
Subject(s)
Diabetes Mellitus, Type 2/epidemiology , Dietary Fats/administration & dosage , Fatty Acids/administration & dosage , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/prevention & control , Dietary Fats/adverse effects , Fatty Acids/adverse effects , Humans , Incidence , Observational Studies as Topic , Protective Factors , Risk Assessment , Risk FactorsABSTRACT
PURPOSE OF REVIEW: Nutrition recommendations emphasize that not only dietary fat quantity but also fat quality plays a role in the prevention of type 2 diabetes (T2D). The aim of this review is to summarize the evidence for dietary fat and risk of T2D, to highlight recent findings and point out future research directions. RECENT FINDINGS: Total fat intake was not associated with risk of T2D, whereas the findings on fatty acids (FAs) and risk of T2D were controversial. Recent findings suggested that FAs from the same classes (e.g. omega-6 FAs) but different sources might be differently associated with the risk of T2D, with indication for an association with lower risk of T2D for plant-based and higher risk/no association for animal-based FAs. In addition, differences between populations from different geographic areas might exist, but no interaction effects for fat intake and genetic predisposition were observed regarding T2D risk. The simultaneous investigation of different fats and dietary patterns can provide important and meaningful insights into these associations. SUMMARY: The evidence for the association between dietary fat intake and risk of T2D is not conclusive yet. To strengthen the evidence, the complexity of the different associations of dietary fats should be considered in well conducted future studies.
Subject(s)
Diabetes Mellitus, Type 2/epidemiology , Dietary Fats/adverse effects , Humans , RiskABSTRACT
Background: Epidemiologic studies have indicated that breakfast skipping is associated with risk of type 2 diabetes. However, the shape of the dose-response relation and the influence of adiposity on this association have not been reported. Objective: We investigated the association between breakfast skipping and risk of type 2 diabetes by considering the influence of the body mass index (BMI). Methods: In this systematic review and meta-analysis, PubMed and Web of Science were searched up to August 2017. Prospective cohort studies on breakfast skipping and risk of type 2 diabetes in adults were included. Summary RRs and 95% CIs, without and with adjustment for BMI, were estimated with the use of a random-effects model in pairwise and dose-response meta-analyses. Results: In total 6 studies, based on 96,175 participants and 4935 cases, were included. The summary RR for type 2 diabetes comparing ever with never skipping breakfast was 1.33 (95% CI: 1.22, 1.46, n = 6 studies) without adjustment for BMI, and 1.22 (95% CI: 1.12, 1.34, n = 4 studies) after adjustment for BMI. Nonlinear dose-response meta-analysis indicated that risk of type 2 diabetes increased with every additional day of breakfast skipping, but the curve reached a plateau at 4-5 d/wk, showing an increased risk of 55% (summary RR: 1.55; 95% CI: 1.41, 1.71). No further increase in risk of type 2 diabetes was observed after 5 d of breakfast skipping/wk (P for nonlinearity = 0.08). Conclusions: This meta-analysis provides evidence that breakfast skipping is associated with an increased risk of type 2 diabetes, and the association is partly mediated by BMI.
Subject(s)
Breakfast , Diabetes Mellitus, Type 2/etiology , Feeding Behavior , Adult , Humans , Risk FactorsABSTRACT
The aim of this study was to assess the effects of different dietary approaches on low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and triglyceride (TG) levels in patients with type 2 diabetes (T2D) by applying network meta-analysis (NMA). Systematic electronic and hand searches were conducted until January 2018. Randomized controlled trials (RCTs) with an intervention period of ≥ 12 weeks, focussing on adults with T2D, and comparing dietary approaches regarding LDL, HDL or TGs, were included. For each outcome measure, random effects NMA was performed in order to determine the effect of each dietary approach compared to every other dietary intervention. Mean differences (MDs) and 95% confidence intervals (95% CIs) were calculated, and for the ranking, the surface under the cumulative ranking curves (SUCRA) was determined. Additionally, the credibility of evidence was evaluated. 52 RCTs (44 for LDL, 48 for HDL and 52 for TGs) comparing nine dietary approaches (low fat, vegetarian, Mediterranean, high protein, moderate carbohydrate, low carbohydrate, control, low glycaemic index/glycaemic load and Palaeolithic diet) enrolling 5360 T2D patients were included. The vegetarian diet most effectively reduced LDL levels [MD (95% CI): - 0.33 (- 0.55, - 0.12) mmol/L; compared to the control diet]. The Mediterranean diet beneficially raised HDL [MD (95% CI): 0.09 (0.04, 0.15) mmol/L] and decreased TG levels [MD (95% CI): - 0.41 (- 0.72, - 0.10) mmol/L] compared to the control diet. The Mediterranean diet was the most effective dietary approach to manage diabetic dyslipidaemia altogether (SUCRA: 79%). The overall findings are mainly limited by low credibility of evidence.
Subject(s)
Diabetes Mellitus, Type 2/diet therapy , Diet Therapy/methods , Diet, Mediterranean , Lipids/blood , Network Meta-Analysis , Triglycerides/blood , Blood Glucose/analysis , Cholesterol/blood , Cholesterol, HDL/blood , Diabetes Mellitus, Type 2/blood , Humans , Lipoproteins, LDL/blood , Randomized Controlled Trials as TopicABSTRACT
Substitution models in epidemiologic studies specifying both substitute and substituted food in relation to disease risk may be useful to inform dietary guidelines. A systematic review of prospective observational studies was performed to quantify the risks of all-cause mortality, cardiovascular disease, and type 2 diabetes (T2D) associated with the substitution of dairy products with other foods and between different dairy products. We systematically searched MEDLINE, Embase, and Web of Science until 28th June, 2023. We calculated summary relative risks (SRRs) and 95% confidence intervals (95% CI) in random-effects meta-analyses. We assessed the risk of bias with the Risk Of Bias In Non-randomized Studies - of Exposure (ROBINS-E) tool and certainty of evidence (CoE) using the Grading of Recommendations Assessment, Development, and Evaluations (GRADE) approach. Fifteen studies (with 34 publications) were included. There was moderate CoE that the substitution of low-fat dairy with red meat was associated with a higher risk of mortality, coronary artery disease, and T2D [SRR (95% CI): 1.11 (1.06, 1.16), 1.13 (1.08, 1.18), and 1.20 (1.16, 1.25)]. A higher risk of mortality and T2D was also observed when substituting low-fat dairy with processed meat [SRR (95% CI): 1.19 (1.11, 1.28) and 1.41 (1.33, 1.49); moderate CoE]. A lower mortality risk was associated with the substitution of dairy and yogurt with whole grains [SRR (95% CI): 0.89 (0.84, 0.93) and 0.91 (0.85, 0.97)], and butter with olive oil [SRR (95% CI): 0.94 (0.92, 0.97); all moderate CoE]. Mainly no associations were observed when substituting dairy products against each other on disease and mortality risk. Our findings indicate associations between substituting dairy with red or processed meat and higher disease risk, whereas its substitution with whole grains was associated with a lower risk. However, there is little robust evidence that substituting whole-fat with low-fat dairy is associated with disease risk. (CRD42022303198).
ABSTRACT
BACKGROUND: Type 2 diabetes is a major health concern associated with mortality. Diet may influence the progression of diabetes; however, systematic reviews are lacking. PURPOSE: This study systematically summarized the evidence on diet and all-cause mortality in individuals with type 2 diabetes. DATA SOURCES: PubMed and Web of Science were searched until June 2022. STUDY SELECTION: Prospective observational studies investigating dietary factors in association with all-cause mortality in individuals with type 2 diabetes were selected. DATA SYNTHESIS: We identified 107 studies. Moderate certainty of evidence was found for inverse associations of higher intakes of fish (summary risk ratios per serving/week: 0.95; 95% CI 0.92, 0.99; n = 6 studies), whole grain (per 20 g/day: 0.84; 95% CI 0.71, 0.99; n = 2), fiber (per 5 g/day: 0.86; 95% CI 0.81, 0.91; n = 3), and n-3 polyunsaturated fatty acids (per 0.1 g/day: 0.87; 95% CI 0.82, 0.92; n = 2) and mortality. There was low certainty of evidence for inverse associations of vegetable consumption (per 100 g/day: 0.88; 95% CI 0.82, 0.94; n = 2), plant protein (per 10 g/day: 0.91; 95% CI 0.87, 0.96; n = 3), and for positive associations of egg consumption (per 10 g/day: 1.05; 95% CI 1.03, 1.08; n = 7) and cholesterol intake (per 300 mg/day: 1.19; 95% CI 1.13, 1.26; n = 2). For other dietary factors, evidence was uncertain or no association was observed. CONCLUSIONS: Higher intake of fish, whole grain, fiber, and n-3 polyunsaturated fatty acids were inversely associated with all-cause mortality in individuals with type 2 diabetes. There is limited evidence for other dietary factors, and, thus, more research is needed.
Subject(s)
Diabetes Mellitus, Type 2 , Fatty Acids, Omega-3 , Animals , Humans , Diabetes Mellitus, Type 2/etiology , Diet , Prospective Studies , Whole Grains , Observational Studies as TopicABSTRACT
BACKGROUND: Physical activity is a cornerstone in diabetes management; however, evidence synthesis on the association between physical activity and long-term diabetes-related complications is scarce. PURPOSE: To summarize and evaluate findings on physical activity and diabetes-related complications, we conducted a systematic review and meta-analysis. DATA SOURCES: We searched PubMed, Web of Science, and the Cochrane Library for articles published up to 6 July 2021. STUDY SELECTION: We included prospective studies investigating the association between physical activity and incidence of and mortality from diabetes-related complications, i.e., cardiovascular disease (CVD), coronary heart disease, cerebrovascular events, heart failure, major adverse cardiovascular events, and microvascular complications such as retinopathy and nephropathy, in individuals with diabetes. DATA EXTRACTION: Study characteristics and risk ratios with 95% CIs were extracted. Random-effects meta-analyses were performed, and the certainty of evidence and risk of bias were evaluated with use of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) and Risk Of Bias In Non-randomised Studies - of Interventions (ROBINS-I) tools. DATA SYNTHESIS: Overall, 31 studies were included. There was moderate certainty of evidence that high versus low levels of physical activity were inversely associated with CVD incidence, CVD mortality (summary risk ratio 0.84 [95% CI 0.77, 0.92], n = 7, and 0.62 [0.55, 0.69], n = 11), and microvascular complications (0.76 [0.67, 0.86], n = 8). Dose-response meta-analyses showed that physical activity was associated with lower risk of diabetes-related complications even at lower levels. For other outcomes, similar associations were observed but certainty of evidence was low or very low. LIMITATIONS: Limitations include residual confounding and misclassification of exposure. CONCLUSIONS: Physical activity, even below recommended amounts, was associated with reduced incidence of diabetes-related complications.
Subject(s)
Cardiovascular Diseases , Diabetes Complications , Diabetes Mellitus , Humans , Prospective Studies , Diabetes Mellitus/epidemiology , Exercise , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/etiologyABSTRACT
Periodontal disease has been reported to be associated with diabetes mellitus. However, the direction of the association and the influence of bias are not clear. Thus, the aim of this systematic review and meta-analysis was to summarize the existing evidence on the bidirectional prospective association between periodontal disease and diabetes mellitus by accounting for the risk of bias of the original studies. The literature search was conducted on the electronic data sources PubMed and Web of Science up to February 9th, 2021. We included observational studies, which investigated the prospective association between diabetes mellitus and periodontal disease or vice versa. The risk of bias of the primary studies was evaluated by applying the Quality in Prognosis Studies (QUIPS) tool. Random effects models were used to calculate summary relative risk (SRR) with 95% CI. Subgroup analyses were applied to investigate heterogeneity and the robustness of the finding. In total, 15 studies were included . The SRR for incident diabetes mellitus was 1.26 (95% CI 1.12, 1.41; I2: 71%, n = 10; participants = 427,620; identified cases = 114,361), when comparing individuals with periodontitis to individuals without periodontitis. The SRR for incident periodontitis was 1.24 (95% CI 1.13, 1.37; I2: 92%, n = 7; participants = 295,804; identified cases: > 22,500), comparing individuals with diabetes to individuals without diabetes. There were no significant differences between subgroups after stratification for risk of bias. The findings show a positive bidirectional association between periodontal disease and diabetes mellitus, and thus, underline the need for screening of patients with periodontitis regarding diabetes mellitus and vice versa. The main limitation of the study is the high unexplained heterogeneity between the studies including the different assessment methods of the disease diagnosis.
Subject(s)
Diabetes Complications/complications , Diabetes Mellitus/epidemiology , Periodontal Diseases/complications , Cohort Studies , Diabetes Complications/epidemiology , Humans , Periodontal Diseases/epidemiology , Risk Assessment , Risk FactorsABSTRACT
Obesity management guidelines consistently advise aerobic training for weight loss, whereas recommendations for other training modalities are sparse. This systematic review and network meta-analysis (NMA) aimed to compare the long-term effects of different training modalities on anthropometric outcomes in patients with obesity. MEDLINE, Cochrane CENTRAL, and Web of Science were searched to identify the following: (1) randomized controlled trials (RCTs); (2) conducted in adults with a mean body mass index (BMI) ≥30 kg/m2 ; (3) comparing aerobic, resistance, combined, or high-intensity interval training head-to-head or to control for ≥6 months; and (4) reporting changes in body weight (BW), BMI, waist circumference (WC), fat mass (FM), or fat-free mass (FFM). Random-effects NMA models were fitted in a frequentist approach. GRADE framework was used to assess certainty of evidence. Thirty-two RCTs with 4774 participants with obesity were included in this review. Aerobic training was ranked as best for improving BW, BMI, and WC and combined training for improving FM, as well as equally with resistance training most effective for improving FFM. Low to moderate certainty of evidence supports use of aerobic training to improve anthropometric outcomes in obesity, and its combination with resistance training provides additional benefit for reducing FM and increasing FFM.
Subject(s)
Obesity , Resistance Training , Adult , Anthropometry , Body Weight , Humans , Network Meta-Analysis , Obesity/therapyABSTRACT
INTRODUCTION: Women with gestational diabetes mellitus (GDM) have a higher risk of developing type 2 diabetes mellitus compared with women who never had GDM. Consequently, the question of structured aftercare for GDM has emerged. In all probability, many women do not receive care according to the guidelines. In particular, the process and interaction between obstetrical, diabetic, gynaecological, paediatric and general practitioner care lacks clear definitions. Thus, our first goal is to analyse the current aftercare situation for women with GDM in Germany, for example, the participation rate in aftercare diabetes screening, as well as reasons and attitudes stated by healthcare providers to offer these services and by patients to participate (or not). Second, we want to develop an appropriate, effective and patient-centred care model. METHODS AND ANALYSIS: This is a population-based mixed methods study using both quantitative and qualitative research approaches. In various working packages, we evaluate data of the GestDiab register, of the Association of Statutory Health Insurance Physicians of North Rhine and the participating insurance companies (AOK Rheinland/Hamburg, BARMER, DAK Gesundheit, IKK classic, pronova BKK). In addition, quantitative (postal surveys) and qualitative (interviews) surveys will be conducted with randomly selected healthcare providers (diabetologists, gynaecologists, paediatricians and midwives) and affected women, to be subsequently analysed. All results will then be jointly examined and evaluated. ETHICS AND DISSEMINATION: The study was approved by the ethics committee of the Faculty of Medicine, Heinrich-Heine-University Düsseldorf (Ethics Committee No.: 2019-738). Participants of the postal surveys and interviews will be informed in detail about the study and the use of data as well as the underlying data protection regulations before voluntarily participating. The study results will be disseminated through peer-reviewed journals, conferences and public information. TRIAL REGISTRATION NUMBER: DRKS00020283.
Subject(s)
Diabetes Mellitus, Type 2 , Diabetes, Gestational , Aftercare , Child , Diabetes Mellitus, Type 2/therapy , Diabetes, Gestational/therapy , Female , Germany , Humans , Pregnancy , Surveys and QuestionnairesABSTRACT
INTRODUCTION: Lifestyle factors in combination have been hypothesised to be associated with the prevention of type 2 diabetes (T2D) and mortality among individuals with T2D. The aim was to conduct a systematic review and meta-analysis to quantify the association between lifestyle indices and incident T2D as well as mortality in individuals with T2D. METHODS: PubMed and Web of Science were searched up to September 2019. We included prospective cohort studies investigating at least three lifestyle factors in association with T2D, or all-cause mortality in individuals with diabetes. We conducted pairwise and dose-response meta-analyses to calculate summary relative risks (SRR) by using random effects model. RESULTS: In total, 19 studies were included. Adhering to a healthy lifestyle (mostly favourable diet, physical activity, non-smoking, moderate alcohol intake and normal weight) was associated with a reduced SRR of 78% for T2D (SRR: 0.22; 95% CI: 0.16 to 0.32; n=14) and 57% for mortality (SRR: 0.43; 95% CI: 0.31 to 0.58; n=5) compared with low adherence to a healthy lifestyle. In dose-response analyses, the adherence to every additional healthy lifestyle factor was associated with a reduced relative risk of 32% (95% CI: 28% to 36%) for T2D and 21% (95% CI: 15% to 26%) for mortality. CONCLUSIONS: Our findings underline the importance of the joint adherence to healthy lifestyle factors to prevent T2D and improve survival among individuals with diabetes. Adherence to every additional health lifestyle factor play a role in the T2D prevention and progression. PROSPERO REGISTRATION NUMBER: CRD42018091409.
Subject(s)
Diabetes Mellitus, Type 2/epidemiology , Exercise , Healthy Lifestyle , Mortality , Treatment Adherence and Compliance/statistics & numerical data , Diabetes Mellitus, Type 2/mortality , Diet , Humans , Incidence , Risk FactorsABSTRACT
BACKGROUND: There is controversy on the relevance of dietary sugar intake for cardiometabolic health. OBJECTIVE: The aim of this network meta-analysis (NMA) was to assess how isocaloric substitutions of dietary sugar with other carbohydrates affect cardiometabolic risk factors, comparing different intervention studies. METHODS: We included randomized controlled trials (RCTs) investigating the isocaloric effect of substituting dietary sugars (fructose, glucose, sucrose) with other sugars or starch on cardiometabolic risk markers, including LDL cholesterol, triacylglycerol (TG), fasting glucose (FG), glycated hemoglobin (HbA1c), insulin resistance (HOMA-IR), uric acid, C-reactive protein (CRP), alanine transaminase (ALT), aspartate transaminase (AST), and liver fat content. To identify the most beneficial intervention for each outcome, random-effects NMA was conducted by calculating pooled mean differences (MDs) with 95% CIs, and by ranking the surface under the cumulative ranking curves (SUCRAs). The certainty of evidence was evaluated using the Confidence In Network Meta-Analysis tool. RESULTS: Thirty-eight RCTs, including 1383 participants, were identified. A reduction in LDL-cholesterol concentrations was shown for the exchange of sucrose with starch (MD: -0.23 mmol/L; 95% CI: -0.38, -0.07 mmol/L) or fructose with starch (MD: -0.22 mmol/L; 95% CI: -0.39, -0.05 mmol/L; SUCRAstarch: 98%). FG concentrations were also lower for the exchange of sucrose with starch (MD: -0.14 mmol/L; 95% CI: -0.29, 0.01 mmol/L; SUCRAstarch: 91%). Replacing fructose with an equivalent energy amount of glucose reduced HOMA-IR (MD: -0.36; 95% CI: -0.71, -0.02; SUCRAglucose: 74%) and uric acid (MD: -23.77 µmol/L; 95% CI: -44.21, -3.32 µmol/L; SUCRAglucose: 93%). The certainty of evidence was rated very low to moderate. No significant effects were observed for TG, HbA1c, CRP, ALT, and AST. CONCLUSIONS: Our findings indicate that substitution of sucrose and fructose with starch yielded lower LDL cholesterol. Insulin resistance and uric acid concentrations were beneficially affected by replacement of fructose with glucose. Our findings are limited by the very low to moderate certainty of evidence. This review was registered at www.crd.york.ac.uk/prospero as CRD42018080297.
Subject(s)
Cardiovascular Diseases/metabolism , Dietary Sugars/metabolism , Starch/metabolism , Blood Glucose/metabolism , C-Reactive Protein/metabolism , Cardiovascular Diseases/blood , Cholesterol, LDL/metabolism , Fructose/metabolism , Glucose/metabolism , Glycated Hemoglobin/metabolism , Humans , Insulin Resistance , Randomized Controlled Trials as Topic , Sucrose/metabolism , Triglycerides/metabolism , Uric Acid/metabolismABSTRACT
INTRODUCTION: Type 2 diabetes (T2D) is a major health concern associated with several comorbidities such as diabetic chronic kidney disease, neuropathy and cardiovascular diseases. Many of these complications may be preventable by an adequate lifestyle, including a favourable dietary behaviour, additionally to pharmacological management. In general, dietary guidelines for patients with diabetes recommend a hypocaloric diet to achieve a normal weight, but there is a lack of detailed instructions on specific nutrients and foods to prevent diabetes-related outcomes. Therefore, the aim of this systematic review and meta-analysis is to summarise the available evidence on the association between dietary factors and health-related outcomes in patients with T2D. METHODS AND ANALYSIS: A systematic literature search will be conducted in PubMed and Web of Science in May 2019 to identify prospective observational studies investigating dietary factors in association with major complications in patients with T2D. We will include studies investigating dietary patterns, food groups, foods, macronutrients and micronutrients as well as secondary plant compounds. As diabetes-related outcomes, we will include macrovascular (cardiovascular and cerebrovascular diseases) and microvascular outcomes (nephropathy, neuropathy and retinopathy), as well as cancer, quality of life, depression, cognitive disorders and mortality. We will conduct dose-response meta-analyses using random effects models. We will investigate heterogeneity across studies and publication bias. To assess the risk of bias and quality of the included studies, we will use the Cochrane risk of bias tool ROBINS-I and the quality of evidence will be assessed using Grades of Recommendation, Assessment, Development, and Evaluation. ETHICS AND DISSEMINATION: As the systematic review is based on published studies, ethical considerations are not required. The systematic review and meta-analysis will be published in a peer-reviewed Journal. PROSPERO REGISTRATION NUMBER: CRD42018110669.
Subject(s)
Diabetes Mellitus, Type 2 , Health Status , Humans , Diabetes Mellitus, Type 2/diet therapy , Diabetes Mellitus, Type 2/epidemiology , Global Health , Morbidity/trends , Observational Studies as Topic , Prognosis , Prospective Studies , Meta-Analysis as Topic , Systematic Reviews as TopicABSTRACT
This meta-analysis summarizes the evidence of a prospective association between the intake of foods [whole grains, refined grains, vegetables, fruit, nuts, legumes, eggs, dairy, fish, red meat, processed meat, and sugar-sweetened beverages (SSBs)] and risk of general overweight/obesity, abdominal obesity, and weight gain. PubMed and Web of Science were searched for prospective observational studies until August 2018. Summary RRs and 95% CIs were estimated from 43 reports for the highest compared with the lowest intake categories, as well as for linear and nonlinear relations focusing on each outcome separately: overweight/obesity, abdominal obesity, and weight gain. The quality of evidence was evaluated with use of the NutriGrade tool. In the dose-response meta-analysis, inverse associations were found for whole-grain (RRoverweight/obesity: 0.93; 95% CI: 0.89, 0.96), fruit (RRoverweight/obesity: 0.93; 95% CI: 0.86, 1.00; RRweight gain: 0.91; 95% CI: 0.86, 0.97), nut (RRabdominal obesity: 0.42; 95% CI: 0.31, 0.57), legume (RRoverweight/obesity: 0.88; 95% CI: 0.84, 0.93), and fish (RRabdominal obesity: 0.83; 95% CI: 0.71, 0.97) consumption and positive associations were found for refined grains (RRoverweight/obesity: 1.05; 95% CI: 1.00, 1.10), red meat (RRabdominal obesity: 1.10; 95% CI: 1.04, 1.16; RRweight gain: 1.14; 95% CI: 1.03, 1.26), and SSBs (RRoverweight/obesity: 1.05; 95% CI: 1.00, 1.11; RRabdominal obesity: 1.12; 95% CI: 1.04, 1.20). The dose-response meta-analytical findings provided very low to low quality of evidence that certain food groups have an impact on different measurements of adiposity risk. To improve the quality of evidence, better-designed observational studies, inclusion of intervention trials, and use of novel statistical methods (e.g., substitution analyses or network meta-analyses) are needed.