What is the difference between basal-bolus insulin (BBI) therapy and sliding scale insulin (SSI) therapy?

From the Guidelines

Basal-bolus insulin therapy is the preferred approach for managing diabetes, as it provides better glycemic control and reduces complications compared to sliding scale insulin, according to the most recent and highest quality study 1.

Key Considerations

• Basal-bolus therapy involves administering a long-acting insulin once or twice daily, combined with rapid-acting insulin before meals, to provide continuous background insulin coverage and address mealtime glucose spikes.
• Sliding scale insulin, on the other hand, relies solely on short-acting insulin given reactively based on pre-meal blood glucose levels, without providing consistent background insulin.
• The basal-bolus approach has been shown to reduce the risk of postsurgical complications and improve glycemic control in patients with type 2 diabetes, as demonstrated in a study published in The Lancet Diabetes and Endocrinology 1.

Implementation and Education

• Patients should receive education on carbohydrate counting, blood glucose monitoring, and insulin adjustment techniques to optimize their basal-bolus regimen and minimize hypoglycemia risk.
• A typical basal-bolus regimen might include insulin glargine 10-20 units at bedtime with insulin aspart 4-6 units before each meal, adjusted based on blood glucose readings and carbohydrate intake.
• The total daily insulin dose should be individualized, with a recommended dose of 0.3-0.5 U/kg for insulin-naive patients or those treated with low doses of insulin, and a 20% reduction in total daily insulin dose for patients treated with higher doses of insulin at home.

Comparison with Other Regimens

• Premixed insulin therapy has been associated with an unacceptably high rate of iatrogenic hypoglycemia and is not recommended in the hospital, as stated in the study 1.
• A basal-plus approach, which consists of a single dose of basal insulin along with corrective doses of insulin, may be preferred for patients with mild hyperglycemia, those with decreased oral intake, and for patients undergoing surgery, as suggested by the evidence 1.

From the FDA Drug Label

14 CLINICAL STUDIES

1. 2 Clinical Studies in Adult and Pediatric Patients with Type 1 Diabetes Adult Patients with Type 1 Diabetes In two clinical studies (Studies A and B), adult patients with type 1 diabetes (Study A, n=585, Study B n=534) were randomized to 28 weeks of basal-bolus treatment with Insulin Glargine or NPH insulin. In another clinical study (Study C), patients with type 1 diabetes (n=619) were randomized to 16 weeks of basal-bolus treatment with Insulin Glargine or NPH insulin. In these 3 adult studies, Insulin Glargine and NPH insulin had similar effects on HbA1c (Table 9) with a similar overall rate of severe symptomatic hypoglycemia [see Adverse Reactions (6. 1)].

The basal-bolus regimen with Insulin Glargine is compared to NPH insulin in the provided studies, but there is no direct comparison to a sliding scale regimen.

• Basal-bolus regimen: The studies show that Insulin Glargine has similar effects on HbA1c as NPH insulin in adult patients with type 1 diabetes.
• Sliding scale regimen: There is no information provided in the drug label that directly compares basal-bolus to sliding scale regimens. 2

From the Research

Basal Bolus vs Sliding Scale Insulin Therapy

• Basal-bolus insulin therapy has been shown to result in better glycemic control than sliding scale insulin therapy in hospitalized patients 3, 4.
• A study published in the American Journal of Therapeutics found that basal-bolus insulin strategy resulted in better glycemic control and lower risk of hypoglycemia than premixed insulin regimen 3.
• A systematic review and meta-analysis published in Diabetes/Metabolism Research and Reviews found that basal-bolus insulin therapy resulted in significantly lower mean daily blood glucose than sliding scale insulin therapy, but was associated with increased risk of mild hypoglycemia 4.
• The ideal glucose goals for non-critically ill patients remain undefined and must be individualized according to the characteristics of the patients, but a target glucose range of 110-180 mg/dL may be appropriate for most critically ill patients and non-critically ill patients 3.

Efficacy and Safety of Basal Insulin

• Basal insulin glargine has been shown to be effective in reducing HbA1c levels in patients with type 2 diabetes mellitus exhibiting inadequate response to metformin and DPP-4 inhibitors with or without sulfonylurea 5.
• A study published in Diabetes Care found that low-dose insulin glargine combined with a sulfonylurea and metformin resulted in similar A1C improvements compared with add-on maximum-dose rosiglitazone, but was associated with more hypoglycemia and less weight gain 6.
• Biphasic insulin aspart has been shown to provide improved postprandial glucose control compared with biphasic human insulin and NPH insulin, and was not associated with an increased risk of major hypoglycemia 7.