From the Research
Diltiazem does not preserve beta cell function in patients with diabetes or at risk of developing diabetes, and its use may even worsen glucose tolerance and insulin secretion in some cases. The most recent and highest quality study, 1, published in 2019, found that diltiazem treatment exhibited detrimental effects on whole body glucose homeostasis and glucose transport in the striated muscle of patients with diabetes. This study suggests that diltiazem may actually have a negative impact on beta cell function, rather than preserving it.
Some earlier studies, such as 2 and 3, found that diltiazem did not have a significant effect on glucose tolerance or insulin secretion in patients with diabetes. However, these studies were limited by their small sample sizes and short duration of follow-up. In contrast, the 2019 study 1 provides more robust evidence of the potential negative effects of diltiazem on beta cell function.
Another study, 4, found that diltiazem led to a significant increase in beta-cell sensitivity to glucose, but this finding is not consistent with the results of the more recent study 1. Additionally, a case report 5 suggested that diltiazem may have a direct diabetogenic effect, although this finding is based on a single patient and requires further confirmation.
In terms of clinical practice, diltiazem is not recommended for the preservation of beta cell function in patients with diabetes or at risk of developing diabetes. Instead, established approaches to preserving beta cell function include maintaining good glycemic control through diet, exercise, and weight management, along with medications specifically proven to preserve beta cell function such as GLP-1 receptor agonists or early insulin therapy in some cases.
Key points to consider:
- Diltiazem may worsen glucose tolerance and insulin secretion in patients with diabetes
- The medication is primarily used for treating hypertension and certain cardiac conditions
- Established approaches to preserving beta cell function include good glycemic control and medications specifically proven to preserve beta cell function
- More robust clinical evidence is needed to fully understand the effects of diltiazem on beta cell function.