Metabolic syndrome in Bantu subjects with type 2 diabetes from sub-Saharan extraction

High rates of atherogenic dyslipidemia, β-cell function loss, and microangiopathy among Turkish migrants with T2DM

AIMS

Non-Caucasian migrants require dedicated approaches in diabetes management due to specific genetic; socio-cultural; demographic and anthropological determinants. Documenting such phenotypes allows for better understanding unmet needs and management priorities.

METHODS

This age- and sex-adjusted case-control (1:6 ratio) study compared 56 T2DM Turkish migrants (70% males) resident in Belgium [Tu] with 336 T2DM Caucasians [Ca], all benefiting from state-funded healthcare.

RESULTS

The 2 groups did not differ regarding BMI; waist circumference; fat mass; visceral fat; muscle mass; insulin sensitivity; insulinemia; metabolic syndrome; hypertension; lipid-modifying drugs; and macroangiopathy. They also had similar renal function and (micro)albuminuria. Education (low/high) and ethanol consumption were lower among [Tu]: 83/17% and 2.0 U/wk vs 43/57% and 13.6 U/wk in [Ca] (p < 0.0001). β-cell function loss (BCF) was higher in [Tu]: 1.58(0.45) vs 1.35(0.54)%/yr (p 0.0027), as was HbA1c: 8.39(1.91) vs 7.48(1.35)% in [Ca] (p < 0.0001). Diabetes duration and insulin use were increased in [Tu]: 19(9)yr and 70% vs 16(8)yr and 48% in [Ca] (p 0.0111 and 0.0024). Atherogenic dyslipidemia (AD) was more prevalent in [Tu]: 64% vs 49% (p 0.0309), who had higher non-HDL-C; apolipoprotein B₁₀₀; LDL-C; and triglycerides; and lower HDL-C and apolipoprotein A-I levels (all p < 0.05). Overall microangiopathy; retinopathy; and neuropathy were more prevalent in [Tu]: 55-35-37% vs 40-18-20% in [Ca] (all p < 0.05).

CONCLUSIONS

These results should raise concerns about poor glycaemic control; rapid BCF loss; severe AD; and microangiopathy among Turkish migrants with T2DM. Targeting AD could improve the cardiometabolic profile of this minority given the relationship between AD and residual vascular risk.

Log (TG)/HDL-C ratio as a predictor of decreased islet beta cell function in patients with type 2 diabetes: 6-year cohort study

BACKGROUND

The aim of the present study was to explore whether the triglyceride to high density lipoprotein cholesterol ratio [log (TG)/HDL-C] and peripheral blood leukocytes DNA telomere length could predict future islet beta cell function decreased in Chinese type 2 diabetes mellitus (T2DM) during a 6-year cohort.

METHODS

Sixty T2DM patients (without insulin treatment at baseline) were included in the 6-year cohort study. Peripheral blood leukocytes DNA telomere length, HbA1c, blood lipid profile, fatty fat acid, glucose, insulin and C peptide (3 h after a mixed meal) were determined. Delta C peptide area under curve (Delta CP AUC) was used to reflect change in beta cell secretion function (Delta CP AUC = baseline CP AUC - CP AUC after 6 years). Subjects were divided into slow decrease of beta cell function group (Delta CP AUCslow group) and fast decrease group (Delta CP AUCfast group) according to median of Delta CP AUC. Baseline demographic characteristics, clinical variables between two groups were compared. Correlations between baseline data and Delta CP AUC were analyzed.

RESULTS

Baseline log (TG)/HDL-C was positively correlated with Delta CP AUC (r = 0.306, P = 0.027); log (TG)/HDL-C in Delta CP AUCfast group was higher than that in Delta CP AUCslow group (0.103 ± 0.033 vs 0.083 ± 0.030, P = 0.027). There was no significant difference in DNA telomere length between the two groups. Change in DNA telomere length over 6 years was not significantly correlated with baseline blood lipid.

CONCLUSIONS

In Chinese T2DM patients, high baseline log (TG)/HDL-C ratio predicts fast progression of islet beta cell dysfunction. It may be a simple index to predict progression speed of islet beta cell dysfunction.

The atherogenic dyslipidemia ratio [log(TG)/HDL-C] is associated with residual vascular risk, beta-cell function loss and microangiopathy in type 2 diabetes females

Background

Atherogenic dyslipidemia (AD), defined as low HDL-C plus elevated triglycerides (TG), comorbid to T2DM, increases cardiometabolic risk for CAD even when LDL-C is at target. In T2DM males, AD was shown to correlate with β-cell function loss, yet it is not established whether this applies across gender.

Aim

To establish the prevalence and severity of AD in T2DM females, and to determine how it relates to cardiometabolic phenotype, glucose homeostasis, micro- and macrovascular complications, and 10-year absolute CV risk (UKPDS Risk Engine).

Methods

340 T2DM females were ranked according to quintiles (Q) of the continuous variable log(TG)/HDL-C, with AD prevalence defined as HDL-C <50 mg.dL^-1 plus TG ≥150 mg.dL^-1, and β-cell function assessed with HOMA.

Results

AD prevalence was 35%; mean HDL-C and TG were 52 (15) and 160 (105) mg.dL^-1. AD was significantly related to central fat, metabolic syndrome, sedentarity and skeletal sarcopenia, as well as to _hsCRP, fibrinogen, uric acid, cystatin-C, Big ET-1, and 10-year UKPDS CV risk. AD correlated stepwise with lower β-cell function and hyperbolic product, and with accelerated loss of residual insulin secretion, higher HbA_1c and prevalent microangiopathy.

Conclusions

log(TG)/HDL-C is a simple means to grade AD and residual macrovascular risk in T2DM females. This ratio associates with major non-LDL cardiometabolic variables and ranks predicted CAD risk. In addition, log(TG)/HDL-C identifies worsening glucose homeostasis, poorer glycemic control, and prevalent microangiopathy.

The multi-faceted outcomes of conjunct diabetes and cardiovascular familial history in type 2 diabetes

BACKGROUND

Familial history of early-onset CHD (EOCHD) is a major risk factor for CHD. Familial diabetes history (FDH) impacts β-cell function. Some transmissible, accretional gradient of CHD risk may exist when diabetes and EOCHD familial histories combine. We investigated whether the impact of such combination is neutral, additive, or potentiating in T2DM descendants, as regards cardiometabolic phenotype, glucose homeostasis and micro-/macroangiopathies.

METHODS

Cross-sectional retrospective cohort study of 796 T2DM divided according to presence (Diab[+]) or absence (Diab[-]) of 1st-degree diabetes familial history and/or EOCHD (CVD(+) and (-)). Four subgroups: (i) [Diab(-)CVD(-)] (n=355); (ii) [Diab(+)CVD(-)] (n=338); (iii) [Diab(-)CVD(+)] (n=47); and (iv) [Diab(+)CVD(+)] (n=56).

RESULTS

No interaction on subgroup distribution between presence of both familial histories, the combination of which translated into additive detrimental outcomes and higher rates of fat mass, sarcopenia, (hs)CRP and retinopathy. FDH(+) had lower insulinemia, insulin secretion, hyperbolic product, and accelerated hyperbolic product loss. An EOCHD family history affected neither insulin secretion nor sensitivity. There were significant differences regarding macroangiopathy/CAD, more prevalent in [Diab(-)CVD(+)] and [Diab(+)CVD(+)]. Among CVD(+), the highest macroangiopathy prevalence was observed in [Diab(-)CVD(+)], who had 66% macroangiopathy, and 57% CAD, rates higher (absolute-relative) by 23%-53% (overall) and 21%-58% (CAD) than [Diab(+)CVD(+)], who inherited the direst cardiometabolic familial history (p 0.0288 and 0.0310).

CONCLUSIONS

A parental history for diabetes markedly affects residual insulin secretion and secretory loss rate in T2DM offspring without worsening insulin resistance. It paradoxically translated into lower macroangiopathy with concurrent familial EOCHD. Conjunct diabetes and CV familial histories generate multi-faceted vascular outcomes in offspring, including lesser macroangiopathy/CAD.

Hypertriglyceridemia and residual dyslipidemia in statin-treated, patients with diabetes at the highest risk for cardiovascular disease and achieving very-low low-density lipoprotein-cholesterol levels

BACKGROUND

As the result of the high prevalence of comorbidities and conventional risk factors among patients with type 2 diabetes (T2DM), most patients belong to the highest cardiovascular disease risk category, and have a target low-density lipoprotein cholesterol (LDL-C) of <70 mg/dL. Because substantial residual risk persists at LDL-C <70 mg/dL, a more comprehensive control of non-LDL-C and particles was recommended in the joint 2008 American Diabetes Association/American College of Cardiology Consensus.

OBJECTIVE

To ascertain, in statin-treated T2DM patients belonging to this greatest-risk group, with on-statin LDL-C <70 mg/dL, (1) the proportion of patients meeting all three critical levels (LDL-C <70 mg/dL, non-high-density lipoprotein cholesterol [HDL-C] <100 mg/dL, apoB <80 mg/dL) and (2) the variables associated with target attainment versus nonattainment.

PATIENTS AND METHODS

Among 675 unselected patients with T2DM, 367 were both at very high cardiometabolic risk and taking statins; 118 of these patient had LDL-C levels <70 mg/dL. Patients meeting all three criteria (LDL-C, non-HDL-C, and apoB; n = 79; all three at goal group) were compared with those only reaching LDL-C (n = 49; only LDL-C at goal group).

RESULTS

LDL-C was 54 (12) for the all three at goal group versus 57 (10) mg/dL for the only LDL-C at goal group (NS). The two groups were similar regarding age, gender, diabetes duration, body mass index, waist circumference, blood pressure, renal function and micro-/macroangiopathy prevalence. A statin plus fibrate was given to 16% of patients in the all three at goal group and 32% in the only LDL-C at goal group. The two groups did not differ in baseline (prestatin) LDL-C, HDL-C, and non-HDL-C, except for pre-/post-lipid-lowering drug(s) triglycerides (TG): 177 (95)/118 (56) for all three at goal versus 279 (134)/ 241 (103) mg/dL for only LDL-C at goal (P = .0230 and P = .0001). The only LDL-C at goal group had lower HDL-C (vs. all three at goal): 41 (12) vs. 47 (14) mg/dL (P = .0237), with atherogenic dyslipidemia [hypo-HDL-C + hyper-TG] prevalence of 35% in the all three at goal versus 56% in the only LDL-C at goal group (P < .0001). log(TG)/HDL-C was 0.049 (0.021) for all three at goal versus 0.063 (0.021) for only LDL-C at goal (P < .0001). The LDL-C/apoB ratio was 0.92 (0.24) for all three at goal vs. 0.67 (0.18) for only LDL-C at goal (P < .0001), suggestive of smaller/denser LDL.

CONCLUSION

The presence of atherogenic dyslipidemia was associated with a failure to meet all three critical modifiable targets for hypercholesterolemia, such a nonachievement being found in a large proportion (one-third) of very-high risk T2DM patients with very-low on-statin LDL-C. Attainment of all three targets will require (1) titration/permutation of statins, (2) lifestyle (re)inforcement; and/or (3) statin-fibrate bitherapy.

Reducing vascular events risk in patients with dyslipidaemia: an update for clinicians

Reducing the risk of vascular events in patients with dyslipidaemia requires cardiovascular disease risk stratification and lifestyle/pharmacological intervention on modifiable risk factors. Reduction of low-density lipoprotein cholesterol (LDL-C) with statins is highly effective in reducing cardiovascular disease in patients with and without diabetes, but leaves unaddressed a sizeable residual vascular risk (RvR), which is rarely quantified in routine clinical practice. Such RvR may relate to lack of strict target attainment for all atherogenic variables [LDL-C, non-high-density lipoprotein cholesterol (HDL-C) and/or apolipoprotein B(100)]. Another substantial lipid-related and modifiable RvR component is related to atherogenic dyslipidaemia, especially as global rates of obesity, type 2 diabetes and metabolic syndrome are increasing. Atherogenic dyslipidaemia is associated with insulin-stimulated very-low-density lipoprotein overproduction and reduced reverse cholesterol transport. The hallmark of atherogenic dyslipidaemia is the coexistence of low HDL-C and elevated triglycerides. Therapeutic lifestyle changes and combination lipid-lowering therapy with drugs targeting atherogenic dyslipidaemia (such as fibrates or innovative drugs targeting atherogenic dyslipidaemia and/or apolipoprotein B(100) metabolism) on top of background statins, have a potential to reduce RvR in high-risk groups, as shown in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial, in which combination therapy with simvastatin plus fenofibrate decreased macrovascular risk in patients with diabetes and atherogenic dyslipidaemia, and retinopathy risk irrespective of baseline lipids.

Do high ferritin levels confer lower cardiovascular risk in men with Type 2 diabetes?

AIMS

High ferritin levels are associated with insulin resistance and liver steatosis, both thought of as emerging cardiovascular risk factors. The association between ferritin and cardiovascular disease is poorly documented in cardiometabolic states with higher cardiovascular risk, such as diabetes and metabolic syndrome. We therefore characterized a cohort of males with Type 2 diabetes mellitus (T2DM) according to ferritin levels and prevalent macroangiopathy.

METHODS

The presence of overall macroangiopathy, peripheral and/or coronary artery disease was documented in 424 consecutive T2DM males, who were divided according to ferritin quartiles (Q) as follows: QI-III, normal ferritin (NF; n=318), mean+/-1 sd ferritin 133+/-72 ng/ml; and QIV patients, high ferritin (HF; n=106), ferritin 480+/-228 ng/ml.

RESULTS

Age, age at diabetes diagnosis, smoking, ethanol intake, body mass index, waist circumference, blood pressure and presence of metabolic syndrome did not differ between groups. However, the prevalence of macroangiopathy was unexpectedly much lower in patients with high ferritin, as follows: 25% vs. 43% for overall macroangiopathy; 7% vs. 16% for peripheral artery disease; and 16% vs. 31% for coronary artery disease (P=0.0009, P=0.0140 and P=0.0035, respectively, vs. NF patients). Insulin resistance index and prevalence of liver steatosis were higher in HF compared with NF patients as follows: 2.17% vs. 1.89% and 78% vs. 64% (P=0.0345 and P=0.0059, respectively). Liver enzymes (aspartate aminotransferase, alanine aminotransferase and gamma-glutamyl transferase) were significantly higher in HF, by 33%, 42% and 72%, respectively (all P<0.0002), suggesting a higher prevalence of steatohepatitis. Glycated haemoglobin, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, triglycerides, urate, high-sensitivity C-reactive protein and albuminuria were not different between groups.

CONCLUSIONS

Our results demonstrate that T2DM males with high ferritin levels exhibit a markedly decreased prevalence of macroangiopathy, despite more severe insulin resistance and higher markers of steatohepatitis. High ferritin levels and/or steatosis may thus paradoxically confer a lowered cardiovascular risk in diabetic males.

Erectile dysfunction, microangiopathy and UKPDS risk in type 2 diabetes

BACKGROUND

Erectile dysfunction (ED) is a frequent comorbidity in patients with type 2 diabetes mellitus (T2DM), and is now increasingly considered a surrogate marker of endothelial dysfunction as well as a sentinel predictor of new-onset macroangiopathic events. Less attention, however, has been directed at the potential association of ED and microangiopathy in hyperglycaemic states.

METHODS

We analyzed 221 consecutive male T2DM outpatients in whom ED was assessed by the International Index of Erectile Function (IIEF-5) questionnaire. ED(+) patients (IIEF-5 1-20; n=83) were compared with an age-matched ED(-) cohort (IIEF-5 21-25; n=51), with similar diabetes duration, in terms of cardiovascular (CV) risk factors, micro-/macroangiopathy and the United Kingdom Prospective Diabetes Study (UKPDS) risk score.

RESULTS

Mean age and diabetes duration were 58 and 10 years, respectively. IIEF-5 score (1 S.D) was 23 (1) in ED(-) vs 11 (6) in ED(+). Anamnestic impotence and erectogenic drug use were reported by 52% and 36%, respectively, of ED(+) vs 12% and 8%, respectively, of ED(-) (P<0.0002 and P<0.0001, respectively). The metabolic syndrome prevalence (88% vs 64%; P=0.002) and central adiposity markers (waist, waist/height and visceral fat) were all significantly higher in ED(+). HbA(1c) was similar in both groups: 7.5% (1.3%), and there were also no significant differences in smoking, blood pressure, HOMA insulin sensitivity, cholesterol and glomerular filtration rate. However, prevalences of retinopathy, polyneuropathy and elevated albuminuria, and the composite endpoint of peripheral artery disease, transient ischaemic attacks and/or stroke, were markedly increased in ED(+) (all P<0.05). No differences were observed in coronary artery disease prevalence or in the UKPDS 10-year CV risk between the two ED groups.

CONCLUSION

IIEF-5-defined ED in men with T2DM is associated with a marked increase in the metabolic syndrome, central adiposity and microangiopathy. These data suggest that diagnosing ED in T2DM warrants detailed screening and monitoring for microangiopathy in target organs.

Dietary cassava, beta-cell function and hyperbolic product loss rate in type 2 diabetes patients from South Kivu

OBJECTIVE

Cassava, a major carbohydrate source in Africa, contains potentially diabetogenic chemicals, although its consumption is not associated with incident diabetes. As it is not known whether cassava intake impairs residual beta-cell function in patients with type 2 diabetes (T2D), our study compared the metabolic phenotypes of diet- and/or oral antidiabetic drug (OAD)-treated T2D patients in South Kivu (Democratic Republic of the Congo) with [Cassava (+); n=147] and without [Cassava (-); n=46] self-reported cassava consumption.

DESIGN & METHODS

A total of 193 patients [male:female (%) 37:63; mean +/-1 SD age: 56+/-11 years] were interviewed to determine the frequency and distribution of eight major dietary carbohydrate (CHO) sources (cassava, plantain, rice, maize, bread, sorghum, potatoes and legumes). Fasting glucose, insulin and lipid levels were obtained after an overnight fast and OAD discontinuation. Cassava (+) and Cassava (-) groups were compared for HOMA indices of insulin sensitivity (S), beta-cell function (B), hyperbolic product (B x S) and B x S loss rate (B x S LR).

RESULTS

Diabetes duration was 6+/-7 years, age at diabetes diagnosis was 51+/-11 years and BMI was 25+/-5 kg/m(2). Cassava intake was reported by 76% of patients, and amounted to 29+/-11% of their daily CHO intake. The Cassava (-) group ate more plantain, maize, bread and potatoes, and less sorghum. Age, gender and age at diabetes diagnosis did not differ between Cassava (+) and (-) patients, nor did BMI, fat mass, waist circumference, lipid profile and metabolic syndrome prevalence. HOMA indices of S, B, B x S and B x S LR did not differ significantly between groups-Cassava (+) vs (-): S, 114+/-56% vs 114+/-60%; B, 34+/-30% vs 39+/-32%; B x S, 38+/-35% vs 40+/-31%; and B x S LR, 1.19+/-0.84% vs 1.09+/-0.65% per year-nor did the glucose-lowering modalities.

CONCLUSION

Cassava consumption in South Kivu is not associated with changes in T2D phenotype or in the glucose homoeostasis determinants S, B, B x S and B x S LR. Cassava consumption does not accelerate beta-cell function loss in such a population, whose markedly compromised glucose homoeostasis renders them vulnerable to environmentally acquired beta-cell impairment.

Metabolic syndrome, aging, physical inactivity, and incidence of type 2 diabetes in general African population

The first objective of this study was to determine the baseline prevalence of metabolic syndrome and its individual components using the NCEP-R/ATPIII criteria, IDF criteria for Europe, and IDF criteria for Africa: waist circumference of at least 94 cm for men and women. The second objective was to investigate the incidence and the determinants of type 2 diabetes in a prospective cohort of 807 non-diabetic Central Africans aged >or= 40 years from December 2004 to September 2008. During 3,156 person-years of median follow up, there were 93 type 2 diabetes cases (11.5%), corresponding to an incidence of 29 (95% CI 15-43) per 1,000 person-years. The independent predictors of incident type 2 diabetes were age >or= 45 years, physical inactivity, non-diabetic hyperglycaemia and metabolic syndrome regardless of criteria used. In conclusion, urgent prevention strategies are needed to curb the type 2 diabetes epidemic in Africa.