Diabetic Gastroparesis Pathophysiology Disrupts Insulin Timing, Necessitating Personalized Therapeutic Strategies

Diabetic gastroparesis (DGP) is a chronic, often underrecognized complication of diabetes mellitus characterized by delayed gastric emptying without mechanical obstruction. It represents a significant manifestation of diabetic autonomic neuropathy, arising from a complex interplay of sustained hyperglycemia, oxidative and nitrosative stress, advanced glycation end-product accumulation, impaired insulin/IGF-1 signaling, lipid dysmetabolism, and inflammatory activation. This multifaceted damage to autonomic and enteric neurons, reduced interstitial cells of Cajal density, and disrupted gastric smooth muscle function leads to unpredictable gastric motility. The resulting temporal mismatch between nutrient absorption and insulin pharmacokinetics complicates glycemic control, predisposing patients to early postprandial hypoglycemia followed by late hyperglycemia, increasing glycemic variability and vascular risk.

This narrative review synthesized current literature on diabetic gastroparesis (DGP), examining its complex pathophysiology and clinical implications for insulin therapy. The authors discussed diagnostic strategies, nutritional interventions, and pharmacological treatments, with particular attention to insulin timing modulation. They also analyzed the emerging role of diabetes technologies, including continuous glucose monitoring (CGM) and automated insulin delivery (AID) systems, alongside future perspectives such as glucose-responsive insulins and regenerative approaches targeting gastric neuromuscular dysfunction. The review aimed to outline a mechanism-based, personalized therapeutic strategy for improving metabolic stability and patient outcomes.

The review elucidated that DGP's pathophysiology involves a convergence of hyperglycemia, oxidative stress, advanced glycation end-product (AGE) accumulation, impaired insulin/IGF-1 signaling, and inflammatory activation, which collectively damage autonomic and enteric neurons, reduce interstitial cells of Cajal density, and disrupt gastric smooth muscle function. This leads to impaired and unpredictable gastric motility. Consequently, the altered timing and variability of gastric emptying disturb the physiological coordination between nutrient absorption and insulin pharmacokinetics. This temporal mismatch generates a pattern of early postprandial hypoglycemia followed by late hyperglycemia, significantly increasing glycemic variability. > This pattern complicates insulin dose adjustment, contributing to increased oxidative stress and heightened vascular risk in patients with DGP. The review highlighted that current therapeutic approaches, including insulin timing modulation, nutritional interventions, and pharmacological treatments, aim to mitigate these effects, while emerging technologies like CGM and AID systems offer promising tools for improved management.