Effect of tirzepatide on blood pressure and lipids: A meta-analysis of randomized controlled trials

Rapid Gastric emptying in spontaneously hypertensive rats

OBJECTIVE

To assess the rate of gastric emptying in spontaneously hypertensive rats (SHR) and to evaluate rapid gastric emptying as a possible predisposing factor for hypertension. Rapid gastric emptying of carbohydrates, known to elevate postprandial serum glucose, has been reported to occur in many insulin-resistant states, including hypertension. SHR exhibit insulin resistance similar to human hypertensive patients. No prior studies have assessed gastric emptying of an oral glucose solution in SHR as compared with control Wistar Kyoto rats (WKY).

METHODS

Using scintigraphic imaging, gastric emptying of a physiologic, orally consumed glucose solution was assessed in 12 SHR and 12 control WKY at 5 weeks of age, prior to the development of hypertension, and at 12 weeks of age after hypertension was fully established.

RESULTS

At 5 weeks, the gastric half-emptying time (GHET) was 67.8 ± 9.8 min for the SHR vs. 109.3 ± 18 ( P  = 0.042) minutes for the WKY controls. At 12 weeks, the GHET was 37.29 ± 10.3 min for the SHR vs. 138.53 ± 37.6 ( P  = 0.016) min for the WKY controls.

CONCLUSION

Gastric emptying was significantly more rapid in the SHR before and after the development of hypertension. Even though SHR are known to have increased sympathetic activity associated with their development of hypertension, this increased sympathetic activity does not inhibit gastric emptying. SHR are a promising animal model for investigating therapeutic agents for treating hypertension aimed at slowing the rate of gastric emptying.

Effect of tirzepatide on albuminuria levels and renal function in patients with type 2 diabetes mellitus: A systematic review and multilevel meta-analysis

AIM

The present systematic review aimed to summarize the available evidence from published randomized controlled trials (RCTs) regarding the effect of tirzepatide on albuminuria levels and renal function in patients with type 2 diabetes mellitus.

MATERIALS AND METHODS

Medline (via PubMed), Cochrane Library and Scopus were searched until 20 October 2023. Double-independent study selection, data extraction and quality assessment were performed. Evidence was pooled with a three-level mixed-effects meta-analysis.

RESULTS

In total, 9533 participants from eight RCTs were analysed. All RCTs had a low risk of bias, according to the Cochrane Collaboration tool (RoB2). Tirzepatide was associated with a significantly greater reduction in urine albumin-to-creatinine ratio compared with controls [mean difference (MD) -26.9%; 95% confidence interval (CI) (-34.76, -19.04); p < .001; level of evidence (LoE) moderate]. This effect remained significant in participants with baseline urine albumin-to-creatinine ratio ≥30 mg/g [MD -41.42%; 95% CI (-54.38, -28.45); p < .001; LoE moderate]. Based on subgroup analysis, the comparative effect of tirzepatide was significant against placebo and the insulin regimen, whereas no difference was observed compared with semaglutide. The beneficial effect of tirzepatide on albuminuria levels remained significant across all investigated doses (5, 10 and 15 mg), showing a dose-response relationship. A neutral effect was observed on the estimated glomerular filtration rate [MD 0.39 ml/min/1.73m2 ; 95% CI (-0.64, 1.42); p = .46; LoE moderate].

CONCLUSION

Our findings suggest that tirzepatide probably leads to a significant reduction in albuminuria across all administered doses, while its use is associated with a neutral effect on creatinine clearance as a measure of renal function.

Incretin Therapies for Patients with Type 2 Diabetes and Chronic Kidney Disease

Since the early 2000s, an influx of novel glucose-lowering agents has changed the therapeutic landscape for treatment of diabetes and diabetes-related complications. Glucagon-like peptide-1 (GLP-1) receptor agonists represent an important therapeutic class for the management of type 2 diabetes (T2D), demonstrating benefits beyond glycemic control, including lowering of blood pressure and body weight, and importantly, decreased risk of development of new or worsening chronic kidney disease (CKD) and reduced rates of atherosclerotic cardiovascular events. Plausible non-glycemic mechanisms that benefit the heart and kidneys with GLP-1 receptor agonists include anti-inflammatory and antioxidant effects. Further supporting their use in CKD, the glycemic benefits of GLP-1 receptor agonists are preserved in moderate-to-severe CKD. Considering current evidence, major guideline-forming organizations recommend the use of GLP-1 receptor agonists in cases of T2D and CKD, especially in those with obesity and/or in those with high cardiovascular risk or established heart disease. Evidence continues to build that supports benefits to the heart and kidneys of the dual GLP-1/glucose-dependent insulinotropic polypeptide (GIP) receptor agonist tirzepatide. Ongoing outcome and mechanistic studies will continue to inform our understanding of the role of GLP-1 and dual GLP-1/GIP receptor agonists in diverse patient populations with kidney disease.