Nutritional Strategies for the Management of Type 2 Diabetes Mellitus: A Narrative Review

BACKGROUND

Thinking about greater adherence to dietary planning, it is extremely important to be aware of all nutritional strategies and dietary prescriptions available in the literature, and of which of them is the most efficient for the management of T2DM.

METHODS

A search was carried out in 2023 for randomized clinical trials, systematic reviews, meta-analyses, and guidelines in the following databases: Pubmed, Scielo, Web of Science, CrossRef and Google Scholar. In total, 202 articles were collected and analyzed. The period of publications was 1983-2023.

RESULTS

There is still no consensus on what the best nutritional strategy or ideal dietary prescription is, and individuality is necessary. In any case, these references suggest that Mediterranean Diet may of greater interest for the management of T2DM, with the following recommended dietary prescription: 40-50% carbohydrates; 15-25% proteins; 25-35% fats (<7% saturated, 10% polyunsaturated, and 10% monounsaturated); at least 14 g of fiber for every 1000 kcal consumed; and <2300 mg sodium.

CONCLUSIONS

Individuality is the gold standard for dietary prescriptions, however, the Mediterranean diet with low levels of carbohydrates and fats seems to be the most promising strategy for the management of T2DM.

Infliximab reduces cardiac output in rheumatoid arthritis patients without heart failure

OBJECTIVE

Human anti-tumor necrosis factor (TNF-α) monoclonal antibody (infliximab) is used to treat autoimmune diseases such as rheumatoid arthritis (RA). Although the risk of worsening heart failure has been described in patients under chronic treatment, the acute cardiovascular effects of this drug are unknown in RA patients without heart failure.

METHODS

14 RA patients with normal echocardiography and no history of heart failure were evaluated during the 2-hour infliximab (3-5 mg/kg) infusion period, using a noninvasive hemodynamic beat-to-beat system (Portapres). Stroke volume (SV); systolic, diastolic and mean blood pressures (SBP, DBP and MBP, respectively); cardiac output (CO); heart rate (HR); and total peripheral vascular resistance (PVR) were recorded. All patients also received saline infusion instead of infliximab as a control. Significant differences in hemodynamic parameters were determined using Tuckey's test. All values were expressed as mean ± standard deviation (SD).

RESULTS

Fourteen RA patients (6M/8F) with mean age of 47.2 ± 8.8 years were evaluated. A significant decrease was found in cardiac output and stroke volume (7.04 ± 2.3 to 6.12 ± 2.1 l/min and 91 ± 29.0 to 83 ± 28.8 mL/beat, respectively) after infliximab infusion. Although not statistically significant, a progressive increase was detected in SBP, DBP and total PVR during infusion. Saline infusion did not cause significant hemodynamic changes in the same group of RA patients. No adverse effects were observed during the infusion period.

CONCLUSION

Acute infliximab administration decreased cardiac output due to low stroke volume in RA patients without heart disease. The results also demonstrated that, in spite of its negative inotropic effect, infliximab enhanced BP, probably by increasing PVR.

Acute effects of pharmacotherapies in blood pressure in normotensive moderate smokers

This study was designed to evaluate the changes in arterial blood pressure (BP) and heart rate (HR) in moderate smokers during smoking abstinence after 7 days of treatment with bupropion alone, transdermal nicotine or bupropion combined with transdermal nicotine. Twenty-four healthy moderate smokers (12 female/12 male; 40+/-7 years) were evaluated randomly on five occasions and their systolic, diastolic, mean arterial blood pressure (MAP) and HR were measured by a Finapres device for 10 h, immediately after smoking interruption. All of the 24 smokers participated on five protocols during 7 days: control group (C) - no drugs; placebo group (PL); bupropion group (BUP) 150-300 mg; transdermal nicotine group (TN) - 21 mg; and BUP+TN-nicotine patch. Concomitantly, the subjects were evaluated by ABPM (ambulatory BP monitoring). All of BP parameters monitored shown significant statistical differences in the BUP, TN and BUP+TN groups compared with the controls (p<0.05), when measured by Finapres. The HR remained unaltered in all of the groups. No significant differences were seen in the BP or HR during the 24-h ABPM. These findings indicate that in moderate smokers, bupropion, transdermal nicotine or bupropion associated with transdermal nicotine caused an elevation in the BP after acute smoking interruption.

Hemodynamic effects of a combination of bupropion and nicotine in anesthetized dogs

Bupropion has been used to treat psychic depression and as a therapy for smoking cessation, the latter mainly in association with nicotine. However, there have been no detailed studies of the hemodynamic effects of the association of bupropion with nicotine during replacement therapy. In this study, we evaluated the effects of such an association on the cardiovascular parameters in anesthetized dogs. Bupropion, either alone or together with nicotine, had no significant effect on the cardiac index (CI; 4.7 +/- 0.2 vs 4.3 +/- 0.1 and 3.5 +/- 0.3 vs 3.4 +/- 0.3 L x min(-1) x m(2), respectively; mean +/- SEM) and mean arterial pressure (MAP; 134 +/- 5.0 vs 145 +/- 11.0 and 118 +/- 5.0 vs 133 +/- 10.5 mmHg, respectively). There was a slight but significant increase in the systemic vascular resistance index (SVRI; 2,165 +/- 93 vs 2,645 +/- 126 and 2,335 +/- 100 vs 2,737 +/- 200 dyn x cm(-5)m(-2), respectively). However, there was a significant increase in the mean pulmonary artery pressure (MPAP; 20 +/- 0.8 vs 25 +/- 1.6 and 18 +/- 1.3 vs 25 +/- 1.6 mmHg, respectively; p < 0.05) and pulmonary vascular resistance index (IRVP; 194 +/- 11 vs 272 +/- 21 and 206 +/- 32 vs 307 +/- 42 dyn x cm-5m(-2), respectively; p < 0.05). These results show that bupropion alone or in association with nicotine does not markedly affect most hemodynamic parameters of the systemic circulation, although the significant increase in MPAP and IRVP can elevate the pulmonary pressure.

Low-renin (volume dependent) mild-hypertensive patients have impaired flow-mediated and glyceryl-trinitrate stimulated vascular reactivity

BACKGROUND

Low-renin (volume-dependent) hypertension represents 25-30% of all cases of primary hypertension. Endothelial dysfunction and vascular remodeling are associated with hypertension but their relevance to volume-dependent hypertension (VDH) is not yet known. To evaluate this, flow-mediated dilation (FMD) of the brachial artery and the carotid intima-media thickness in the distal common carotid artery were measured and compared between renin-dependent mild-hypertensive patients (RDH) and controls.

METHOD AND RESULTS

The study group comprised 40 mild-hypertensive patients and 25 controls. Plasma renin activity (PRA), plasma aldosterone concentration, angiotensin II and nitrite/nitrate plasma levels were measured. According to PRA, subjects were classified as VDH (<0.6 ng . ml (-1) . h(-1)), or RDH (>0.6 ng . ml(-1) . h (-1)). Vascular function was evaluated by FMD before and after reactive hyperemia (RH) and glyceryl-trinitrate (GTN) administration. FMD in response to RH and GTN in the VDH group when compared with RDH group was 10.2+/-2.8% vs 13.3+/-3.6% (p=0.01); and 16.0+/-3.5% vs 19.9+/-4.5% (p=0.01), respectively.

CONCLUSION

This study showed impaired FMD and reduced GTN response in mildly hypertensive patients with low-renin plasma levels.