Diabetes Flashcards
(25 cards)
What is Diabetes mellitus
group of disorders compromising abnormalities of metabolism (fat, protein and carbohydrate), characterized by hyperglycemia resulting from insulin deficiency or resistance (prevalence for both is increasing)
Signs of Type I diabetes (insulin dependent)
weight loss, polyuria, polydypsia, ketosis (keto-acidotic coma)
Type II diabetes (non-insulin dependent)
often asymptomatic, overweight, infections (urinary tract, vulva), thirst, rarely coma
Complications of Diabetes
blindness, kidney damage, CVD and lower limb amputations -> people can lower occurrence of these by controlling glucose, blood pressure and blood lipid
Incidence of diabetes
higher frequency in Pima Indians and other Native Americans, blacks and Hispanics, lower frequency in whites
Etiology of Type I diabetes
T cell mediated autoimmune disease -> genetic factors (HLA linked) account for 40% of risk (low penetrance), environmental (60% of risk) = viruses (rubella, enterovirus, coxsackievirus, CMV), dietary factors (cow’s milk protein/bovine serum albumin/BSA, early introduction of gluten before 3 months, vitamin D intake protects, breast feeding protects)
Hygiene hypothesis for type I diabetes
environment for young children may be too clean leading to a deficiency in immunoregulation -> low level of expression of gene in heterozygote
Cow’s milk
increase in consumption shows increase in prevalence in countries where consumption is higher -> THEORIES: immature gut mucosa allows antigenic protein to cross (beta casein, beta lactoglobin, albumin -> molecular mimicry of pancreatic beta cell) -OR- bovine insulin in milk may trigger antibodies to insulin *NB: Breastfeeding is protective, DO NOT GIVE COW’S MILK
Type II Diabetes etiology
strong environmental etiology, pathogenesis is defective insulin secretion and action (resistance) -> SECRETORY DEFECT (especially with genetic transmission) -> low birth weight (maternal malnutrition?), chronic hyperglycemia (high glycemic index foods?); PERIPHERAL INSULIN RESISTANCE (impaired insulin-mediated glucose uptake in muscles) -> genetic is 50%, weight gain is 25% and physical inactivity is 25% -> obesogenic environment
Risk factors for type II diabetes
age, family history, ethnic group, social class, fetal nutrition and early growth pattern, diet (SFA), inadequate physical activity, central obesity, metabolic syndrome
Body weight/pattern and type II risk
for each 1kg increase in weight in the population, risk increases by 4.5% -> central adiposity is most important (>1.02 in men and .88 in women have higher insulin levels and are more insulin resistant than patients with similar weight but with peripheral obesity
Central obesity
can result in the metabolic syndrome (most prevalent cause) -> is also a precursor for type II diabetes and atherosclerotic vascular disease -> pattern is more common in men (risk of CVD is same in men and women, but men smoke more, have higher BP/cholesterol and are more likely to have this pattern)
Metabolic syndrome
glucose intolerant, centrally obese (associated with insulin resistance or hyperinsulinemia), HTN, dyslipidemia (increased TAGs or decreased HDL) -> need 3 for diagnosis ->result from failure of the normal actions of insulin -> interrelated with type II diabetes and CVD (increases risk of CHD death and non-fatal MI risk)
Visceral fat
drains directly to the liver via the portal system (peripheral fat does not), more NEFA produced than from gluteal-femoral fat (Non esterified FA delivery to muscle causes insulin resistance), more inflammatory cytokines (causes IR) than from gluteal-femoral fat, adipocytes located here are larger and more resistant to insulin than those in the periphery
Hyperinsulinemia
directly related to waist circumference
Treatment of diabetes
type I: diet/lifestyle and insulin, type II: diet/lifestyle +/- oral hypoglycemic drugs +/- insulin -> 23% take no medication
Lifestyle changes/dietary principles for diabetes treatment and prevention
weight control/lose weight/increase exercise -> modest energy deficit within a healthy diet, moderate alcohol consumption, regular meals (snacks in type I) -> COMPLICATED DIETS DON’T WORK
Reduce saturated fat
causal factor in insulin resistance (experimental and cross-sectional -> more than it causes atherosclerosis) -> substitution with either PUFA or MUFA reduces insulin resistance (makes membrane more fluid) and changes abdominal fat distribution
Fish oils have an overall benefit in diabetes
activate a macrophage receptor in intraperitoneal macrophages resulting in broad anti-inflammatory effects and improved systemic insulin sensitivity
Maintain general health for adults
30 min/day of moderate intensity activity, 5 days a week -> reduces risk of CVD, premature death and some cancers -> reduces risk of type II diabetes -> improves psychological well-being (can be in 10 minute bouts)
To prevent obesity
45-60 minutes a day of moderate intensity
For children/young people
60 minutes/day of moderate intensity exercise, five days a week -> plus twice a week activities to improve bone health and muscle strength and flexibility
Diet and exercise
equally effective in preventing diabetes but not additive -> more effective than medication
Metformin
improves glycemic control and reduces diabetic complications by reduction of hepatic gluconeogenesis, decreased absorption of glucose from the GI tract and increased insulin sensitivity -> HALF as effective as lifestyle changes
