The Diabetes Epidemic--Part I
The Impact of Oral Healthcare Providers
THE NEXT DDS
Worldwide, 220 million people have diabetes.1
Data indicate that global factors such as population growth, aging,
urbanization, and increasing prevalence of obesity and physical inactivity will
cause the number of cases of diabetes to double by the year 2030.2
In the US, most recent figures (2008) indicate that 24 million people or nearly
8% of the population have the disease.3 The Centers for Disease
Control (CDC) predict that if the current trends continue, 1 in 3 Americans
will develop diabetes in their lifetime, and will lose on average, 10-15 years
of life.4 As the rate of diabetes increases, it is likely that
dental practitioners will treat more individuals living with this chronic and
debilitating disease.
TYPES OF DIABETES
Diabetes is a group of diseases characterized by high levels
of blood glucose (hyperglycemia) resulting from defects in insulin production,
insulin action or both. The type of diabetes an individual has is dependent
upon the circumstances at the time of diagnosis. The diagnosis of diabetes
traditionally has been based upon glucose criteria. In 2010, the American
Diabetes Association included the A1C test, a reading that reflects average
blood glucose over the preceding 2-3 months as one of the tests to diagnose
diabetes. The three most common types of diagnosed diabetes are: Type 1, Type
2, and Gestational diabetes. In recent years, a new category for those at
increased risk was developed. These individuals are referred to as having
pre-diabetes.5
Type 1
Previously called juvenile or insulin-dependent diabetes,
type 1 diabetes develops when the body’s immune system destroys pancreatic beta
cells, the cells of the body responsible for insulin production. The cause of
type 1 is not well known. It is likely that there may be a genetic
predisposition as well as related environmental factors. People with type 1
must take insulin to stay alive. Type 1 accounts for about 5%-10% of all cases
of diabetes.5 Three quarters of Type 1 cases are diagnosed in
children < 18 years of age; however it can occur at any time.6
About 15,000 youth are newly diagnosed with type 1 each year.7
The onset of type 1 diabetes is often acute or mimics the
flu. Symptoms of type 1 diabetes are often referred to as polyuria (frequent
urination), polydipsia (unusual thirst), and polyphagia (extreme hunger). Other
symptoms include unexplained weight loss, extreme fatigue, and irritability.
Diagnosis usually occurs fairly soon after the on-set of symptoms. Children
with type 1 may have other autoimmune diseases such as celiac disease and
autoimmune thyroiditis.6
Type 2
Once called adult-onset or non-insulin dependent diabetes,
type 2 diabetes usually begins as insulin resistance, a disorder where cells do
not use insulin properly. Over time, as the need for insulin increases, the
pancreas gradually loses its ability to produce insulin. Diet, exercise, oral
hypoglycemic drugs, and insulin all may be used in the treatment of type 2
diabetes. Currently, this type accounts for 90% to 95% of diabetes cases.6,7
People with undiagnosed diabetes most often have type 2. The
signs and symptoms of type 2 diabetes may be similar to those for type 1 but
may also include frequent infections, blurred vision, cuts/bruises that are
slow to heal, tingling/numbness in the hands or feet, or recurring skin,
periodontal, or bladder infections. Many individuals with type 2 diabetes have
no symptoms and may go undiagnosed for several years; often until other health
complications appear.8
The risk of developing type 2 diabetes increases with age,
obesity, and lack of physical activity. Type 2 is associated with family
history and may be more likely to occur in those with a history of gestational
diabetes or impaired glucose tolerance, now called pre-diabetes. Type 2 is more
likely to occur in adults age 40 and over, but with increasing rates of
childhood obesity, there are approximately 3,700 cases of type 2 in children
diagnosed annually. Type 2 diabetes onset may be delayed or even prevented by
lifestyle changes.7
Gestational Diabetes
Mellitus (GDM)
Gestational diabetes has been defined as any degree of
glucose intolerance with onset or first recognition during pregnancy. This type
of diabetes affects about 7% of pregnancies resulting in 200,000 cases per
year. Risk assessment for GDM generally occurs at the first prenatal visit.
Individuals who are obese, have a history of previous GDM, or a strong family
history of diabetes may be tested in the first trimester. Women of average risk
are generally tested at 24 –28 weeks gestation. GDM usually resolves with
delivery, however glycemic testing should be performed six weeks post partum to
confirm.5 There has been a progressive increase (10%) in the number
of women whose diabetes does not resolve after pregnancy. It is believed that
they had undiagnosed type 2 diabetes prior to pregnancy not GDM.9
Children born to mothers with GDM are at an increased risk
of having a large birth weight. They are also at risk for becoming obese,
glucose intolerant, and developing diabetes in late adolescence and young
adulthood. Women with GDM are more likely to develop hypertension during
pregnancy and/or need a cesarean delivery.10 They also have 40%-60%
chance of developing diabetes in the next 5 - 10 years.7
Pre-Diabetes
Pre-diabetes is the name given to the condition where
individuals have glucose levels that do not meet the criteria for diabetes but
are higher than those considered normal. This includes those who have an
impaired fasting plasma glucose level between 100 mg/dl and 125 mg/dl or
impaired glucose tolerance of 140 mg/dl to 199 mg/dl. An A1C in the range of
5.7% to 6.4% may also be considered a risk factor.5 It is estimated that 57
million people age 20 and over and 7% of adolescents aged 12-19 years have
prediabetes.7 People with pre-diabetes are at higher risk for
developing type 2 diabetes, although lifestyle changes can prevent or delay the
onset.7,11 Screening for pre-diabetes is recommended for adults of
any age who are overweight and/or obese and have one or more additional risk
factors for diabetes. General screening for those without risk factors should
begin at age 45.6
(Continued from page 1 )
IMPACT OF DIABETES
Diabetes is the seventh leading cause of death in the US. It is
generally thought to be underreported as the main cause of death and more
likely to be recorded as a contributing cause. Overall, the risk of death for
people with diabetes is twice that of those without. Both type 1 and type 2
diabetes can lead to serious complications such as those considered
microvascular; retinopathy (eye disease), nephropathy (kidney disease),
neuropathy (nervous system disease) and macrovascular (heart disease and
stroke).7 These complications are a major factor in the temporary
and permanent disability of a person with diabetes.12 The cost of
these complications results in medical expenditures that are 2.3 times higher
than in the absence of diabetes.7
Health Issues
Microvascular
Complications
Diabetic retinopathy refers to any abnormality of the small
blood vessels of the retina such as weakening of blood vessel walls or leakage
from blood vessels. It is the most frequent cause of new cases of blindness
among adults aged 20 - 74 years.7 Nearly all individuals with type 1
diabetes and more than 60% of those with type 2 develop retinopathy within 20
years of diagnosis. Up to 21% of those with type 2 have retinopathy at the
initial diagnosis.13 People with diabetes are 40% more likely to
suffer from glaucoma and 60% more likely to develop cataracts.14
After 15 years of having diabetes, approximately 2% become blind and 10%
develop a severe visual impairment.1
Diabetic nephropathy is a progressive disease involving
damage to the blood vessels of the kidneys that act as filters to remove
wastes, chemicals, and excess water from the blood. When blood vessels are
damaged they allow protein to leak into the urine (called proteinuria).
Diabetic nephropathy accounts for about 40% of new cases of end stage renal
disease (ESRD). While about 30-40% of patients develop nephropathy, those with
type 1 are more likely to progress to ESRD.15 About 10-20% of people
with diabetes succumb to kidney failure.1
Diabetic neuropathy is a form of nervous system damage often
evidenced by a loss of protective sensation often afflicting the feet. About
60% of people with diabetes have mild to severe forms of nervous system damage.
This can include impaired feeling in the feet or hands, slowed digestion,
carpal tunnel syndrome or erectile dysfunction. Severe forms of this can lead
to lower extremity amputation.7 The risk of foot ulcer and/or
amputation is increased in people who have had diabetes for more than 10 years,
are male, have poor glucose control, or have other complications;
cardiovascular, retinal, or renal.16
Macrovascular
Complications
Heart disease and stroke are leading causes of
diabetes-related death. In 2004, heart disease was noted on 68% of diabetes related
deaths and stroke in 16% of cases. In adults with diabetes the risk for coronary
heart disease (CDH) and stroke is 2 to 4 times higher than for adults without
diabetes.7 People with diabetes are at risk of developing CHD up to
fifteen years earlier than other people.17 In more than 20% of cases
in people aged 50-75 years, CHD may be asymptomatic.18 Diabetes has
also been shown to significantly affect mortality within thirty days after a
coronary event.19
Risk factors for CHD and stroke (collectively,
cardiovascular disease, CVD) are hypertension and high cholesterol. Seventy-five
percent of people with diabetes have hypertension defined as blood pressure
≥130/80 or use prescription medication to control blood pressure. In those
with type 1 diabetes, hypertension may result from nephropathy.7
Individuals with type 2 often have lipid abnormalities as evidenced by high
cholesterol, particularly a high LDL and low HDL, and high triglycerides.6
Other Complications
People with diabetes may be more susceptible to other
illnesses, and once they acquire them, may have a worse prognosis. When they
get pneumonia or influenza, they have an increased risk of dying.7
Emerging evidence indicates that both depression and dementia may be more
likely in people with diabetes.20,21 People susceptible to
depression seem to be those with low levels of education, physical impairment
or CVD.20 People with type 2 diabetes seem to have an increased risk
of both Alzheimer’s disease and Vascular dementia.21 There are two
possible ways this may happen. One theory is that neurons in the brain are
affected by blood vessel damage to the brain, and blood vessel damage is a
common complication of diabetes. Another pathway may relate to insulin. High
insulin levels sometimes occur in people with type 2 as the pancreas pumps out
higher levels of insulin in an effort to get a response in insulin resistant
cells. When there is too much insulin, the body becomes overloaded with enzymes
trying to break it down so that ameyloid protein accumulates in the brain
leading to plaque formation.22
Disability
People with diabetes are at a greater risk of temporary
incapacity and permanent disability. Disability from diabetes may prevent
people from working or limit their employment opportunities.22 It
has been shown to interfere with activities of daily living such as walking,
climbing stairs, doing housework, and preparing meals. Older women (≥60 years)
with diabetes had a 58% likelihood of falling compared to women without
diabetes.12
Economic Implications
The population with diabetes tends to be older and sicker
resulting in high health care costs. In the year 2007, the total estimated
costs for diabetes was $174 billion including $116 billion in direct medical
costs and $58 billion in reduced national productivity. About $1 for every $10
spent on health care is attributed to diabetes, and $1 in every $5 is spent on
caring for someone with diabetes. People with diabetes incur approximately
$11,744 in health care expenditures per year compared to $5,095 for people
without diabetes. About 50% of health care expenditures in people with diabetes
are for hospital inpatient care followed by diabetes medication and supplies
(12%), prescriptions for diabetic complications (11%) and physician office
visits (9%).23
Disparities Across
Population Groups
Diabetes becomes more prevalent after the age of 20
affecting 10.7% of that population group. It is the most prevalent in people
over 60 years of age with about 23% being affected. In the last few years, a
trend shows that people are being diagnosed at earlier ages with more than half
of new cases of diabetes occurring in adults between the ages of 40 and 59
years. Type 2 diabetes, while still infrequent, has also become more common
among youth aged 10-19 years. Men have a slightly higher incidence than women,
11.2% versus 10.2%.
Minority groups seem to have a higher risk of developing
type 2 diabetes. African American, Hispanic, American Indian, and Alaskan
Native adults are twice as likely to have diabetes as Caucasians.4
Minority populations have been shown to develop diabetes earlier.7
Minority women are 2 to 4 times more likely to
have diabetes than white women. These groups are more likely to have
diabetes complications that can lower quality of life.24
(Continued from page 2 )
RISK FACTORS
People who are at risk for type 2 diabetes often have a
genetic predisposition. Yet in most cases an environmental trigger like being
overweight or obese is also necessary.25,26 Not all individuals with
a family history will develop diabetes nor will every overweight or obese
person. From a family history perspective, the risk for developing type 2
diabetes is 1 in 7 if you have a parent diagnosed before the age of 50 and 1 in
13 if the parent was diagnosed after age 50. If both parents have type 2, the
risk increases to 1 in 2.25
Overweight/obese is the strongest environmental risk factor
for type 2. Overweight individuals are twice as likely to develop type 2 as
those of a normal weight. For those who are obese, the risk ranges from 3 to 6
times more likely depending on body mass index (BMI).26
The increase in type 2 diabetes has been attributed to the
growing numbers of overweight and obese individuals. The metabolic and
endocrine function of adipose tissue is influenced by obesity resulting in a
greater production of agents that increase insulin resistance and systemic
inflammation.28 A 2010 report found that 68% of US adults are
overweight or obese. For men the rate is 72.3% versus 64.1% for women. However,
women were more likely to be obese than men, 35.5% versus 32.2%. The overall
prevalence of obesity is 33.8%.29 Results from the Framingham Heart
Study indicate that overweight and obesity in adulthood are associated with
large decreases in life expectancy and increases in early mortality.30
Obesity affects children and adolescents. Current statistics indicate that
10.4% of children ages 2-5 are obese as is 19.6% of 6-11 year olds, and 18.1%
of 12-19 year olds.30 Studies have found that obese children and
adolescents are more likely to become obese as adults.32
Emerging data suggests that the role of overweight/obesity
is influenced by the location of weight on the body.33,34,35 A large
waist circumference (greater than 35 inches for women and more than 40 inches
for men) means more abdominal or visceral fat, which has been shown to increase
the risk of both CVD and diabetes. Waist circumference is increasing in youth
at a pace faster than BMI.34 Visceral fat increases the likelihood
of having fat around internal organs. A recent study found that those who had
the highest amount of fat in the liver were more likely to be insulin
resistant.36 Fat concentrated in the gluteofemoral areas of the body
tends to be more passive than abdominal fat and may exert protective
properties.35
Another emerging risk factor for type 2 is smoking. A
systematic review and meta-analysis of 25 published papers found that heavy
smoking (more than 20 cigarettes per day) increased the risk of developing type
2 diabetes. The reason for this relationship has not been conclusively
determined although some factors have been identified. While older studies
showed that smokers tended to have lower BMIs than non smokers, a more recent
investigation showed that today, smokers tend to have higher BMIs.
Additionally, smokers with a normal BMI have been found to have greater
abdominal fat. It is also possible that nicotine may exert a biological
influence on the beta cells of the pancreas as smoking has also been shown to
be a risk factor for pancreatitis and pancreatic cancer.37
Conclusion
Diabetes is a disease the affects more than 200 million people
around the world. There are two distinct kinds of diabetes, type I and type II,
each with its own symptoms and challenges. There are a multitude of systemic
and oral health implications diabetes can have on dental patients both young
and old, which may require special accommodations to be made during treatment. For
more information about this topic, continue on to part II of this article by
visiting This Link.
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