Glucose monitoring

Continuous glucose monitoring (CGM) was first reviewed by the HTA program in 2011.

  • In 2017, the HCA director selected glucose monitoring for rereview based on newly available published evidence that could change the original coverage determination.
  • A rereview of glucose monitoring was conducted in 2018.

Status: Decision completed

Policy context

Glucose monitoring (CGM) was proposed for rereview based on new evidence and expanded indications for use. 

Primary criteria ranking

  • Safety = Medium
  • Efficacy = High
  • Cost = High
Documents (all assessments)

Documents (2018 assessment)

Documents (2011 assessment)

Assessment timeline (2018)

  • Draft key questions published: August 16, 2017
  • Public comment period: August 16 to 29, 2017
  • Final key questions published: September 14, 2017
  • Draft report published: November 9, 2017
  • Public comment period: November 9 to December 8, 2017
  • Final report published: December 29, 2017
  • HTCC public meeting: January 19, 2018


Diabetes mellitus (DM), or diabetes, is a serious metabolic disease characterized by chronic elevation of blood glucose (i.e., hyperglycemia) resulting from defects in insulin secretion, insulin action, or both. No definitive cure is known at this time. Diabetes is generally categorized into three major types based on etiology: Type 1 diabetes (T1DM) (formerly called juvenile diabetes or insulin-dependent diabetes mellitus [IDDM]), Type 2 diabetes (T2DM) (formerly called adult onset diabetes mellitus [AODM] or non-insulin dependent diabetes [NIDDM]), and gestational diabetes mellitus (GDM). 

Diabetes is a leading cause of morbidity and mortality and is associated with substantial health care and societal costs. An estimated 29.9 million Americans (9.3% of the population) had diabetes in 2015 and, by 2050, the prevalence of diabetes in the U.S. adult population is projected to increase to between 21% and 33%. Serious complications related to diabetes include diabetic ketoacidosis (DKA) and hyperosmolar hyperglycemic nonketotic syndrome (HHNS), as well as longer term morbidity due to microvascular (e.g., retinopathy, nephropathy, neuropathy) and macrovascular (e.g., heart disease, stroke) complications; other diabetes related complications include increased risk of infections, cancer and other autoimmune disorders including celiac sprue, thyroid disease, rheumatoid arthritis, and vitiligo.

Intensive insulin therapy, a term used to describe tight management of blood glucose levels, has been shown to reduce the risk of long-term diabetic complications by lowering average blood sugar levels, but also increases the risk of hypoglycemia, which can result in serious morbidity and even death, and causes fear of hypoglycemia which is a major barrier to optimal glucose control.

Real-time continuous glucose monitoring (CGM) is advanced glucose monitoring technology that continuously measures interstitial glucose levels, displays the current blood glucose level as well as the direction and rate of change, and uses alarms and alerts to inform patients when blood glucose is exceeding or falling below specified thresholds.  Conventional fingerstick self-monitoring of blood glucose (SMBG), sometimes called intermittent monitoring, is a technique for testing blood glucose using a portable glucose meter designed for home use. SMBG provides an instantaneous reading of current blood glucose levels at single points in time, but cannot indicate whether the glucose level is on its way up or down. CGMs were designed to aid in the detection of episodes of hyperglycemia and hypoglycemia, facilitating both acute and long term therapy adjustments, which may minimize these excursions. With the exception of one FDA-approved device (Dexcom G5 Mobile CGM System), CGMs are intended to complement, not replace, information obtained from a standard home glucose monitoring device; they are not intended to be used directly for making therapy adjustments, but rather to provide an indication of when a fingerstick may be required. CGMs can be used as stand-alone devices or in conjunction with compatible insulin pumps.