Diabetes as a risk factor for pneumococcal disease and severe related outcomes and efficacy/effectiveness of vaccination in diabetic population. Results from meta-analysis of observational studies

AIMS

To collect all available evidence on the effect of diabetes mellitus (DM) as a risk factor for pneumococcal disease incidence and related complications, and on the efficacy/effectiveness of vaccines in patients with DM.

METHODS

Two distinct systematic searches on MEDLINE, Cochrane, ClinicalTrials.gov and EMBASE databases were performed, one for each meta-analysis, collecting all observational (cohort and case-control) studies and randomized clinical trials performed on humans up to June 1st, 2023.

RESULTS

We retrieved 36 observational studies comparing risk for pneumococcal disease and related complications in people with or without DM, and 11 studies (1 randomized clinical trial and 10 observational studies) assessing conjugated and polysaccaridic vaccines efficacy/effectiveness on preventing such outcomes. People with DM were at higher risk for Invasive Pneumococcal Disease (unadjusted OR 2.42 [2.00; 2.92]); Case-Fatality Rate (unadjusted OR 1.61 [1.25; 2.07], Pneumococcal pneumonia (unadjusted OR 2.98 [2.76; 3.22), and Intensive care unit admission for pneumococcal disease (unadjusted OR 2.09 [1.20; 3.66]). In diabetic individuals vaccinated with conjugated vaccine, incidence of pneumonia specific for vaccine type in a clinical trial (OR 0.237 [0.008; 0.704]), and hospitalization for overall pneumonia during the year following the polysaccharide vaccination in observational studies (unadjusted OR 0.63 [0.45-0.89]) were significantly lower in comparison with unvaccinated DM subjects, with no significant differences for other outcomes.

CONCLUSIONS

People with diabetes mellitus are at higher risk for less favourable course of pneumococcal disease and should be therefore targeted in vaccination campaigns; more evidence needs to be collected on vaccination outcomes in people with diabetes.

An integrated care pathway for cancer patients with diabetes: A proposal from the Italian experience

Diabetes and cancer frequently coexist in the same subject, often with relevant clinical effects on the management and prognosis of the comorbid patient. The existing guidelines, however, do not appropriately address many clinical issues in this setting. Although collaboration between diabetologists and oncologists should play an important role in achieving appropriate levels of care, close coordination or agreement between these specialists is seldom offered. There is an urgent need for greater interdisciplinary integration between all specialists involved in this setting, for a shared approach ensuring that organisational silos are overcome. To this end, the Italian Associations of Medical Diabetologists (AMD) and the Italian Association of Medical Oncology (AIOM) recently established a dedicated Working Group on 'Diabetes and Cancer'. The working group outlined a diagnostic and therapeutic clinical pathway dedicated to hospitalised patients with diabetes and cancer. In this article, we describe the Italian proposal including some suggested measures to assess, monitor and improve blood glucose control in the hospital setting, to integrate different specialists from both areas, as well as to ensure discharge planning and continuity of care from the hospital to the territory.

Early Detection of Microvascular Changes in Patients with Diabetes Mellitus without and with Diabetic Retinopathy: Comparison between Different Swept-Source OCT-A Instruments

Optical coherence tomography angiography (OCT-A) has recently improved the ability to detect subclinical and early clinically visible microvascular changes occurring in patients with diabetes mellitus (DM). The aim of the present study is to evaluate and compare early quantitative changes of macular perfusion parameters in patients with DM without DR and with mild nonproliferative DR (NPDR) evaluated by two different swept-source (SS) OCT-A instruments using two scan protocols (3 × 3 mm and 6 × 6 mm). One hundred eleven subjects/eyes were prospectively evaluated: 18 healthy controls (control group), 73 eyes with DM but no DR (no-DR group), and 20 eyes with mild NPDR (DR group). All quantitative analyses were performed using ImageJ and included vessel and perfusion density, area and circularity index of the FAZ, and vascular complexity parameters. The agreement between methods was assessed according to the method of Bland-Altman. A significant decrease in the majority of the considered parameters was found in the DR group versus the controls with both instruments. The results of Bland-Altman analysis showed the presence of a systemic bias between the two instruments with PLEX Elite providing higher values for the majority of the tested parameters when considering 6 × 6 mm angiocubes and a less definite difference in 3 × 3 mm angiocubes. In conclusion, this study documents early microvascular changes occurring in the macular region of patients at initial stages of DR, confirmed with both SS OCT-A instruments. The fact that early microvascular alterations could not be detected with one instrument does not necessarily mean that these alterations are not actually present, but this could be an intrinsic limitation of the device itself. Further, larger longitudinal studies are needed to better understand microvascular damage at very early stages of diabetic retinal disease and to define the strengths and weaknesses of different OCT-A devices.

Baseline glucose homeostasis predicts the new onset of diabetes during statin therapy: A retrospective study in real life

OBJECTIVE

We evaluated the risk of altered glucose levels and new-onset diabetes (NOD) associated with statins according to glucose levels at baseline in a population treated for dyslipidemia on primary prevention for >5 years.

DESIGN

The retrospective study included 308 subjects (265 on statins and 43 controls on diet) with a follow-up of 5-15 years. The cohort was classified according to glucose tolerance at both baseline and follow-up.

RESULTS

The cumulative incidence of NOD was 13.6% (9.3% in controls and 13.5% in treated patients). NOD was diagnosed after 3.4±1.8 years. In the group with normal glucose levels at baseline, a family history of diabetes (OR: 3.4, 95% CI 1.3-8.9), BMI >30 kg/m2 (OR: 8.5, 95% CI 2.0-35.8), treatment with thiazide (OR: 21.9, 95% CI 1.2-384.2) and no alcohol consumption (OR: 0.3, 95% CI 0.1-0.8) reduced the risk of developing altered glucose levels or NOD. No effects of statins were seen. In the group with altered glucose levels at baseline, hypertension (OR: 5.0, 95% CI 1.0-25.3) and hypertriglyceridemia (OR: 3.5, 95% CI 1.0-11.8) increased the risk of remaining with altered glucose levels or developing NOD. Treatment with statins (OR: 7.5, 95% CI 1.5-37.4), in particular atorvastatin, was associated with an increased risk. In the whole population, statin therapy (OR: 4.0, 95% CI 1.1-14.1, p<0.020), and in particular simvastatin and atorvastatin, was associated with increased risk of altered glucose levels or NOD. Patients who developed or maintained altered glucose levels or NOD had a poor metabolic phenotype at baseline.

CONCLUSIONS

Statins were associated with an increased risk of NOD or altered glucose levels, mainly in subjects with altered glucose levels before the beginning of therapy. Poor metabolic phenotype and unhealthy behaviors or family history of diabetes contributed to that risk.

One-year treatment with liraglutide improved renal function in patients with type 2 diabetes: a pilot prospective study

Unlike GLP-1, liraglutide is not cleared by the glomerulus and its pharmacokinetic is not altered in patients with mild renal impairment. The aim of our study was to analyze the effects of liraglutide on renal function in patients with type 2 diabetes. A twelve-month longitudinal prospective post-marketing study was performed. According to eGFR (estimated glomerular filtration rate) calculated with CKD-EPI equation, 84 consecutive patients were divided in Group A (eGFR > 90 ml/min) and Group B (eGFR < 90 ml/min). BMI, glucose, HbA1c, serum creatinine, microalbuminuria, and eGFR were evaluated at baseline and after 12 months of treatment. A reduction in fasting plasma glucose (p < 0.01), HbA1c (p < 0.003), BMI (p < 0.01), and systolic (p < 0.01) and diastolic blood pressure (p < 0.006) was recorded irrespective of eGFR category. Concerning renal function, creatinine levels had a trend to decrease in both groups. eGFR did not change in Group A, while it increased in Group B (p < 0.05) independently from the concomitant changes of other parameters. Moreover, seven out of 41 patients of Group B had increased eGFR levels which reached the normal values (>90 ml/min). At baseline, five patients had pathological microalbuminuria, but at 12 months three of them returned to normal albuminuria (p < 0.006). Total microalbuminuria levels improved in both groups (p < 0.02). According to preliminary data in animals, our study shows that liraglutide is effective in preserving eGFR in diabetic patients, increasing it in those with reduced renal function. This was associated with a decrease of frequency of patients positive to microalbuminuria. Further studies are needed to confirm these data.

Does statin therapy reduce plasma VEGF levels in humans? A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The effect of statins on plasma concentrations of vascular endothelial growth factor (VEGF), the main angiogenic growth factor with pro-inflammatory and atherogenic properties, is controversial. A systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to obtain a conclusive result in humans.

METHODS

PubMed-Medline, SCOPUS, Web of Science and Google Scholar databases were searched to identify RCTs investigating the impact of statins on plasma VEGF concentrations. A random-effects model and the generic inverse variance method were used for quantitative data synthesis. Meta-regression, sensitivity analysis and publication bias assessments were performed using standard methods.

RESULTS

Eight RCTs examining the effects of statins on plasma VEGF concentrations were included. Meta-analysis suggested a significant reduction of plasma VEGF levels following statin therapy (weighed mean difference: -19.88 pg/mL, 95% CI: -35.87, -3.89, p=0.015). VEGF reductions were observed in the subsets of trials with treatment durations ≥4 weeks (-19.54, -37.78, -1.30, p=0.036), LDL-C reductions ≥50 mg/dL (-28.59, -43.68, -13.50, p<0.001), lipophilic statins (-22.31, -40.65, -3.98, p=0.017), and diseased populations (-21.08, -39.97, -2.18, p=0.029), but not in the opposite subsets. Meta-regression also suggested a significant association between changes in plasma VEGF levels and LDL-C changes, treatment duration, but not molar dose of statins.

CONCLUSIONS

These results suggest a significant reduction in plasma VEGF concentrations following statin therapy. This effect depends on duration of treatment, LDL-lowering activity, lipophilicity of statins, and health status of studied individuals. Further RCTs are needed to explore if the VEGF reduction is implicated in the statin benefits on cardiovascular outcomes.

Blood glucose pre-prandial baseline decreases from morning to evening in type 2 diabetes: role of fasting blood glucose and influence on post-prandial excursions

BACKGROUND

To know the relationships between pre- and postprandial blood glucose (BG), i.e. BG profile shape, is a requisite for an appropriate therapy for type 2 diabetic patients. In non diabetic subjects, pre-breakfast, pre-lunch and pre-dinner BG are similar, so that BG postprandial excursions are superimposed on a stable BG preprandial baseline. We aimed to clarify: (a) whether BG preprandial baseline is stable also in type 2 diabetes and (b) whether fasting BG (FBG) influences the slope of BG preprandial baseline and the relationships between pre- and postprandial BG.

DESIGN

We evaluated self-measured BG profiles of 237 type 2 diabetic patients on diet alone (M/F, 152/85; age 58.6 +/- 0.7 years; years from diagnosis 4.8 +/- 0.6; BMI 28.0 +/- 0.3 kg m-2): 536 profiles containing preprandial BG (corresponding HbA1c 6.8 +/- 0.06%) and 208 profiles containing both pre- and postprandial BG (corresponding HbA1c 6.8 +/- 0.09%). The profiles, measured by nurses, of 866 type 2 diabetic patients on diet alone were also considered (corresponding HbA1c 6.7 +/- 0.04%).

RESULTS

In self-measured profiles containing only preprandial BG: (i) FBG (6.77 +/- 0.07 mmol L(-1)) is higher than pre-lunch BG (6.09 +/- 0.07 mmol L(-1)), P = 0.0001) and pre-dinner BG (5.84 +/- 0.06 mmol L(-1)), P =0.0001); (ii) the delta value between FBG and pre-dinner BG is correlated with FBG (r = 0.57, P = 0.0001), the highest FBG, the steepest the fall of BG preprandial baseline throughout the day. This trend is confirmed in profiles measured by nurses. In profiles containing both pre- and postprandial BG: (i) there is a trend to preprandial BG fall (P = 0.0001) and to postprandial BG increase (P = 0.0001) from morning to evening; (ii) postprandial excursions are influenced and sometimes masked by the slope of BG preprandial baseline, thus, in profiles with FBG < or = 6.7 mmol L(-1), all postprandial values are higher than FBG (P = 0.0001), whereas in profiles with FBG > 7.8 mmol L(-1), postprandial values are not significantly higher than FBG.

CONCLUSION

In type 2 diabetes, the shape of BG profiles changes in relation to FBG, because it deeply influences the slope of BG preprandial baseline on which postprandial excursions are superimposed. Thus, before planning treatment policies, not only the extent of fasting and postprandial hyperglycaemia, but also the shape of profiles should be considered, to safely correct hyperglycaemia without inducing hypoglycaemia.

Platelet resistance to nitrates in obesity and obese NIDDM, and normal platelet sensitivity to both insulin and nitrates in lean NIDDM

OBJECTIVE

Previous studies in our laboratory showed that the platelet anti-aggregating effect exerted by insulin, mediated by a nitric oxide (NO)-induced increase of guanosine-3',5'-cyclic monophosphate (cGMP), is lost in the insulin-resistant of obesity and obese NIDDM. It is not clear 1) whether the alterations observed in obese NIDDM patients are attributable to the obesity-related insulin resistance or to diabetes per se and 2) whether insulin-resistant states present a normal or a blunted response to NO. This study has been conducted to investigate 1) the platelet sensitivity to insulin in lean NIDDM and 2) the platelet sensitivity to an NO donor, glyceryl trinitrate (GTN), in obesity and in both lean and obese NIDDM.

RESEARCH DESIGN AND METHODS

We determined 1) ADP-induced platelet aggregation and platelet cGMP content in platelet-rich plasma (PRP) obtained from 11 lean NIDDM patients, after a 3-min incubation with insulin (0, 240, 480, 960, 1,920 pmol/l) and 2) ADP-induced platelet aggregation and platelet cGMP content in PRP obtained from 9 obese subjects, 11 lean and 8 obese NIDDM patients, and 18 control subjects, after a 3-min incubation with 0, 20, 40, and 100 mumol/l GTN.

RESULTS

Insulin dose-dependently decreased platelet aggregation in lean NIDDM patients (P = 0.0001): with 1,920 pmol/l of insulin, ADP ED50 was 141.5 +/- 6.4% of basal values (P = 0.0001). Furthermore, insulin increased platelet cGMP (P = 0.0001) from 7.5 +/- 0.2 to 21.1 +/- 3.7 pmol/10(9) platelets. These results were similar to those previously described in healthy subjects. GTN reduced platelet aggregation in all the groups (P = 0.0001) at all the concentrations tested (P = 0.0001), but GTN IC50 values were much higher in insulin-resistant patients: 36.3 +/- 5.0 mumol/l in healthy control subjects, 26.0 +/- 6.0 mumol/l in lean NIDDM patients (NS vs. control subjects), 123.6 +/- 24.0 mumol/l in obese subjects (P = 0.0001 vs. control subjects), and 110.1 +/- 19.2 mumol/l in obese NIDDM patients (P = 0.0001 vs. control subjects). GTN dose-dependently increased platelet cGMP in all the groups (P = 0.0001 in control subjects, lean NIDDM patients, and obese subjects; P = 0.04 in obese NIDDM patients). Values reached by obese subjects and obese NIDDM patients, however, were lower than those reached by control subjects (with 100 mumol/l of GTN, P = 0.001 and P = 0.0001, respectively). In healthy control subjects and in obese subjects, the insulin:glucose ratio, used as an indirect measure of insulin sensitivity, was positively correlated to GTN IC50 (r = 0.530, P = 0.008), further suggesting that the sensitivity to NO is reduced in the presence of insulin resistance.

CONCLUSIONS

The insulin anti-aggregating effect is preserved in lean NIDDM; platelet sensitivity to GTN in preserved in lean NIDDM but is reduced in the insulin-resistant states of obesity and obese NIDDM. Resistance to nitrates, therefore, could be considered another feature of the insulin-resistance syndrome.

Impaired insulin-induced platelet antiaggregating effect in obesity and in obese NIDDM patients

To investigate the effects of insulin on platelets in obesity and in non-insulin-dependent diabetes mellitus (NIDDM)--classic insulin-resistant states--we determined ADP-induced platelet aggregation and platelet cGMP (guanosine 3',5'-cyclic monophosphate) content in platelet-rich plasma obtained from nine obese subjects and nine age-matched healthy volunteers and from eight NIDDM obese patients and nine age-matched healthy volunteers after a 3-min incubation with human recombinant insulin (0, 240, 480, 960, and 1,920 pmol/l). Platelet aggregation was evaluated using different ADP doses to measure the ADP concentration determined on the basis of a dose-response curve necessary to elicit a maximal aggregation of 50% (ED50). Insulin induced a dose-dependent decrease of platelet aggregation to ADP (P = 0.0001) in healthy subjects. A significant effect was evident starting from an insulin concentration of 240 pmol/l. On the contrary, in insulin-resistant subjects, insulin reduced platelet sensitivity to ADP only at a concentration of 1,920 pmol/l. When ADP ED50 values obtained in platelet-rich plasma incubated with insulin were expressed in percentage of the ADP ED50 values obtained in platelet-rich plasma without insulin, considered as 100%, we observed that ADP ED50 with 1,920 pmol/l insulin was 153.6 +/- 13.2% in the younger healthy subject group (P = 0.004), 150.0 +/- 3.8% in the older healthy subject group (P = 0.0001), 116.1 +/- 6.1% in obese subjects (P = 0.031), and 120.0 +/- 8.6% in NIDDM patients (P = 0.05). In healthy subjects, insulin induced a dose-dependent increase of platelet cGMP (P = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)