edited version of what sent to me. e-mail Jan for
This memo serves four purposes:
(1) outlines the description and treatment of diabetes mellitus;
(2) reviews the history of Medicare’s coverage policies on diabetes
management;
(3) analyzes the relevant scientific datarelated to the continuous
subcutaneous insulin infusion (CSII) pump;
(4) delineates the reasons supporting a positive national decision to cover
the device for type I diabetics.
Description of Diabetes
A. Pathophysiology
Diabetes Mellitus is a disease of abnormal glucose metabolism characterized
by a deficiency of insulin production, or by development
ofinsulin-resistance, either of which results in abnormally high blood
sugars. Diabetes Mellitus is generally subdivided into two categories: (1)
Type I diabetes mellitus , (also known as insulin dependent diabetes
mellitus [IDDM] or juvenile onset diabetes mellitus) and
(2) Type II diabetes mellitus (also known as non insulin dependent diabetes
mellitus [NIDDM] or adult onset diabetes mellitus)1 Type I diabetes may
begin at any age but onset typically occurs in childhood or adolescence.
Type I diabetes results from an immune mediated destruction of pancreatic
islet beta cells causing decreased endogenous secretion of insulin and
necessitating exogenous insulin therapy to maintain euglycemia.
Type II diabetes is marked by peripheral resistance to the effect of insulin
rather than absolute insulin deficiency.
B. Epidemiology
Approximately 16 million Americans have diabetes, although only slightly
more than 10 million are diagnosed. Type I diabetes accounts for only a
minority (about 5-10%) of the cases of diabetes, with an incidence of 30,000
new cases per year. Most new cases of Type I diabetes occur in patients
under the age of 25 years. Diabetes significantly shortens life expectancy,
and half of all Type I diabetics die before reaching age 50 years. The
overwhelming majority of diabetics have type II diabetes, which has an
incidence of 600,000 new cases per year. Type II diabetes is typically
diagnosed in individuals over the age of 25 years, with almost half of all
new cases occurring in people over age 55 years. Diabetes is especially
significant in the Medicare population as more than 18% of persons over 65
years old have diabetes. (Only 2% of IDDM adults are over 65 years of age.)
C. Cost of diabetes
The acute and chronic complications of diabetes exert a dramatic toll on
both the health care system and the morbidity and mortality of diabetes.
Diabetes is the seventh leading cause of death in the United States,
contributing to more than 193,000 deaths per year. Diabetic complications
include retinopathy, nephropathy, neuropathy, and vascular complications.
Diabetes is the leading cause of blindness, end stage renal disease,
and non-trauma related lower extremity amputations. Additionally, diabetics
have a two to four-fold increased risk of cardiac disease and stroke than
non-diabetics. It is estimated that diabetes is responsible for $96 billion
in direct medical costs and lost productivity each year. The long-term
complications are the largest cost-driver.
Diabetics spend about 24 million days in the hospital each year and it
is estimated that at least 7 million of these hospital days are necessitated
by diabetic complications. For example, Type I diabetics are prone to
develop diabetic ketoacidosis (DKA), a potentially fatal elevation of blood
sugar, which accounts for 3% of all hospital discharges. Both type I and
type II diabetics are predisposed to develop hypoglycemia, which results in
30,000 hospitalizations per year.
Diabetes Treatment
Numerous authors employ the terms “conventional therapy” and “intensive
therapy” with different meanings. This memo will define conventional therapy
for type I diabetes as one or two subcutaneous insulin injections per day.
It will define intensive therapy as treatment aimed at achieving as close to
normoglycemia as possible accomplished either by three or more daily insulin
injections or continuous subcutaneous insulin infusion.
A. Conventional Treatment
Management of diabetes involves efforts to maintain blood glucose levels
near the normal range. Since the discovery of insulin in the 1920s, insulin
replacement has served as the cornerstone of treatment for type I diabetics.
Treatment for type II diabetes is somewhat more varied. Some type II
diabetics achieve adequate glucose control with measures short of insulin
replacement (e.g. diet, exercise, oral medications). A major component of
diabetes treatment involves controlled diet and exercise. Exercise
facilitates glycemic control in two ways: in the short term exercise
decreases immediate insulin requirements, and in the long term exercise
combats obesity induced insulin resistance by promoting weight loss,
especially important for the nearly 40% of Type II diabetics who are
overweight. Many type II diabetics use oral medications (e.g. sulfonlyureas)
to either stimulate the pancreas to secrete more insulin, or to decrease
peripheral resistance.
Under conventional therapy, insulin replacement has been provided with
subcutaneous injections of insulin once or twice each day. For most
patients, this treatment by subcutaneous injections involves some
combination of short acting regular insulin and other longer acting insulin
preparations. Such dosing also requires frequent monitoring of blood glucose
levels, usually by finger-stick.
B. Intensive Control
Within the past few years, “intensive therapy” for diabetes management has
gained favor as it seems to offer the greatest hope of preventing diabetic
complications. Intensive therapy refers to frequent delivery of exogenous
insulin (usually by injection four times a day or alternatively by
continuous infusion) to obtain tight control in the normal blood glucose
range. The Diabetes Control and Complications Trial (DCCT)2, offered
compelling evidence that intensive treatment achieving tight glycemic
control reduces the occurrence of microvascular and neuropathic
complications in patients treated before the development of advanced
disease. This trial involved 1,441 Type I diabetics at 29 medical centers.
On average, patients were followed for an average of 6.5 years (range
3-9 years) before the study was terminated. The study’s principal outcome
measure was retinopathy, but it also included data regarding renal,
neurologic, cardiovascular, and neuropsychological complications as well as
adverse effects from treatment.
The DCCT examined two cohorts, a primary prevention cohort with a
complication-free disease duration of one to five years, and a secondary
intervention cohort with a disease course of one to fifteen years, and the
initial signs of diabetic complications. Subjects were randomly assigned to
the experimental group receiving intensive therapy or the control group
receiving conventional therapy. Subjects in the experimental groups followed
an intensive therapy regimen aimed at achieving as close to normal blood
glucose levels as possible. Intensive therapy subjects had a choice of two
methods of delivery of exogenous insulin; either via three or more daily
insulin injections or external pump. [By the end of the study, 42% of the
experimental subjects were using insulin pumps]. Subjects assigned to
conventional therapy took one or two subcutaneous insulin injections per
day. The study’s results showed members of the intensive therapy group to
have statistically significantly less progression of diabetic complications
than the conventional therapy group: reduction in nephropathy of 34% and 43%
for the primary prevention and secondary intervention cohorts respectively;
76% and 54% reduction in retinopathy, 69% and 57% reduction in neuropathy
(see Table 1). The study found no statistically significant differences in
quality of life between members of the conventional and intensive therapy
groups (based on a questionnaire). The study’s results were so convincing of
the benefits of intensive therapy that the independent data monitoring
committee recommended early termination of the trial. As the evidence
favoring intensive therapy accumulated, investigators could no longer
legitimately encourage subjects to remain in the less effective conventional
therapy group.
Diabetes management has been discussed in the Coverage and Analysis Group at
HCFA for some time. HCFA has strived to ensure that beneficiaries with
diabetes have access to quality care. Most recently, the Balanced Budget Act
of 1997 (BBA ‘97) expanded benefits to patients with diabetes. BBA ‘97
allowed coverage of glucose monitors and test strips for Type II diabetics
as well as expanded the types of diabetes education programs eligible for
Medicare reimbursement
Patient self management plays a critical role in the successful treatment of
diabetes. Traditionally Medicare has paid for some but not all of the tools
required for self management (see Table 2 ). Medicare benefits include
glucometers, lancets, and glucose test strips. Medicare benefits currently
do not include insulin or the syringes, jet injectors, pen-type injectors,
or pumps used to deliver insulin. Patients employing a subcutaneous insulin
infusion pump require somewhat different tools for self management than
practitioners of multiple daily injections (MDI) or conventional therapy.
Like MDI and conventional therapy adherents, pump users would
require glucometers, lancets, and glucose test strips. Pump users would also
require insulin, however, it is either regular or short-acting insulin.
Often, such patients require less insulin to manage their diabetes. Most
significantly, instead of insulin syringes (except for a few back up
syringes to use in case of pump failure), pump users would require an
insulin pump, (which manufacturers estimate to last seven years), and
certain disposable supplies necessary for pump functioning including insulin
reservoirs, infusion sets, sterile adhesive dressings, and batteries.
Meeting, PA, completed an assessment of CSII pumps.5 ECRI concluded that
(1) insulin pump therapy produces greater metabolic control than
conventional therapy (2) insulin pump therapy may produce greater metabolic
control than intensive injection therapy. (3) the success of insulin pump
therapy depends heavily upon proper patient selection, which in turn,
depends heavily upon patient motivation. Regarding risks of severe
hypoglycemic events, ECRI suggested that CSII might offer a decreased risk
compared to MDI but that this is unproven “even though it seems that fewer
severe hypoglycemic episodes are observed during insulin pump therapy than
during intensive injection therapy, it would seem clinically prudent to
assume that the number of these episodes in these two treatment types is
equal.” Of note, ECRI recommended caution in starting pump therapy on
elderly patients
because they may have difficulty responding to the warning symptoms of
hypoglycemia.
HCFA reconsidered its position based on new data as well as the AHCPR
and ECRI reports. Reconsideration of the issue of coverage for insulin pumps
was raised at the Technology Advisory Committee (TAC) meetings of March
26-27, 1996, and August 6-7, 1996. At the March meeting the TAC discussed
CSII and concluded that “there is no justification for coverage of this
service.”
The TAC further decided that CSII lacked clinical evidence of
effectiveness and could not be classified in a coverable benefit category
and as such deemed issuance of a national policy unnecessary. CSII was
further discussed at the August meeting and the TAC expressed concern that
CSII poses potential dangers while its potential benefits have not been
proven for the Medicare
population. The TAC concluded that “the scientific data were not sufficient
to demonstrate that the infusion pump could provide an effective
administration of insulin to any patient in (the) Medicare or non-Medicare
population.”
There has been some discussion about increased incidence of hypoglycemic
unawareness in the elderly. Initially, several authors expressed concern
that tight control would predispose patients to hypoglycemia. For those
patients who had decreased awareness to hypoglycemia, either because of
decreased autonomic response due to previous iatrogenic hypoglycemia or age,
failure to take corrective action may cause such hypoglycemia to be
life-threatening. CSII may actually decrease the frequency of hypoglycemic
events compared to MDI. The pharmacokinetics of insulin delivery via CSII
differs somewhat from subcutaneous injection. Subcutaneous insulin depots
do not accumulate with CSII. Theoretically, this may diminish the risk of
hypoglycemia by eliminating the phenomenon of sudden mobilization of
accumulated insulin by such activities as exercise or other actions that
increase blood flow. Recent studies, also have not substantiated earlier
authors concerns regarding the use of CSII in patients with a history of
hypoglycemia unawareness. In a study on patients with longstanding diabetes
and a history of hypoglycemic unawareness, Cranston and others demonstrated
that unawareness is reversible. Similar results were obtained in a study by
Dagogo-Jack as well as Hirsch and Farkas-Hirsch. Physicians should exercise
caution when they initiate an intensive insulin regimen in patients with a
history of hypoglycemic unawareness, but it should not be a contraindication
to the use of CSII. Within recent years, several authors have proposed
hypoglycemic unawareness as an indication for CSII. Theoretically, the
absence of an insulin depot may cause delivery of insulin via CSII to exert
greater risk of ketoacidosis than conventional injections, but further
studies are required before it can be asserted that this occurs in practice.
CSII is appropriate for individuals who
(1) require or desire improved blood glucose control, especially during
pregnancy; and/or
(2) require the flexibility that CSII offers.” The AADE position statement
comments that hypoglycemia is a concern with CSII but frequent blood glucose
monitoring can help avoid this problem. Like the ADA recommendation, the
AADE position statement does not specifically address whether it refers to
type I or type II diabetics but the references upon which it primarily
relies involved studies on subjects with type I diabetes.
Analysis of Scientific Data on Tight Glycemic Control and CSII for Type II
Diabetes
The preceding scientific discussion focused on Type I diabetes. There are
some studies which have tried to assert that tight glycemic control may help
prevent the progression of diabetic complications in type II diabetics. Some
studies of type II diabetes have compared “intensive” treatment with
“conventional” treatment, but the terms reflected much different therapy
than how they are usually used in type I. For example one study (UKPDS
Lancet, 1998) found intensive treatment of type II diabetes to decrease the
risk of microvascular but not macrovascular complications, and increase the
risk of hypoglycemia. However, where in most of the type I studies,
conventional treatment entailed insulin injections once or twice each day
and intensive treatment entailed CSII or insulin injections three or more
times each day, in the UKPDS study on newly diagnosed type II diabetics,
conventional treatment involved only diet control and intensive treatment
involved use of a sulfonylurea or any injected insulin. The study found that
the intensive therapy group achieved lower mean HbA1c (7%) than the
conventional therapy group (HbA1c 7.9%). The relevance of this study to the
CSII coverage issue is minimal.
DECISION:
Rescind the national noncoverage policy for external continuous
subcutaneous insulin infusion pumps.
Amend Coverage Issues Manual 60-14 to add:
An external infusion pump and related drugs/supplies will be covered as
medically necessary in the home setting in the following situation:
Treatment of Type I diabetes.
In order to be covered, patients must meet criterion A or B:
(A) The patient has completed a comprehensive diabetes education program,
and has been on a program of multiple daily injections of insulin (i.e. at
least 3 injections per day), with frequent self-adjustments of insulin dose
for at least 6 months prior to initiation of the insulin pump, and has
documented frequency of glucose self-testing an average of at least 4 times
per day during the 2 months prior to initiation of the insulin pump, and
meets one or more of the following criteria while on the multiple daily
injection regimen:
(1) Glycosylated hemoglobin level(HbAlc)
(2) History of recurring hypoglycemia
(3) Wide fluctuations in blood glucose before mealtime
(4) Dawn phenomenon with fasting blood sugars frequently exceeding 200 mg/dl
(5) History of severe glycemic excursions
(B) The patient with Type I diabetes has been on a pump prior to enrollment
in Medicare and has documented frequency of glucose self-testing an average
of at least 4 times per day during the month prior to Medicare enrollment.
Type I diabetes needs to be documented by a C-peptide level < 0.5
Continued coverage of the insulin pump would require that the patient has
been seen and evaluated by the treating physician at least every 3 months.
The pump must be ordered by and follow-up care of the patient must be
managed by a physician who manages multiple patients with CSII and who works
closely with a team including nurses, diabetic educators, and dietitians who
are knowledgeable in the use of CSII.
Subcutaneous insulin infusion pumps will continue to be denied as not
medically necessary and reasonable for all Type II diabetics including
insulin-requiring Type II diabetics.
Diabetes Care, 1995
“Hyperglycemia and Microvascular and Macrovascular Disease in
Diabetes”
Review article
discussion of recent studies
NA
“It is not certain whether the findings from the DCCT regarding
intensive insulin treatment for the control of hyperglycemia to prevent
complications of diabetes in people with NIDDM need to be studied in a
clinical trial before a rec can be made”
Excellent discussion of hyperglycemia and diabetic complications.
Emphasize that studies of DCCT cannot yet be generalized to Type II
diabetics. Points out that a VA study actually showed an increased risk of
death secondary to cardiovascular disease in a group of patients with NIDDM
treated with intensive insulin therapy compared with a group treated with
conventional therapy.
In conclusion authors note that benefit of intensive insulin therapy
for type II diabetics with advanced microvascular complications is not yet
established (pg. 115).
Study conducted in Japan - given significant difference between
Japanese and American diets and important role of diet in control of type II
diabetes, the results may not apply to Medicare beneficiaries, most of whom
consume a diet much different from the subjects in the study. Needs to be
replicated.
Main difference between groups was that intensive group received more
diabetes education and greater contact with health care providers, some
patients in each group received three or more daily injections of insulin
and some in each group took two or fewer injections of insulin.
NO subjects used CSII
Pts followed for 18 months, 3, yrs, 5 yrs, 7.5 yrs glycemic control
microvascular complications
102 patients with type I diabetes
mean age = 30 years
at baseline patients had nonproliferative retinopathy, normal serum
creatinine, and poor blood glucose control