Diabetes Mellitus: Type 2 Flashcards
Define T2DM
increased peripheral resistance to insulin action
Impaired insulin secretion
Increased HGO
What are the monogenetic causes of T2DM?
MODY
Mitochondrial diabetes
What increases the risk of T2DM? Why?
Obesity
Due to the action of adipocytokines
What 3 things may T2DM be preceded by?
Pancreatic disease (e.g. chronic pancreatitis) Endocrine disease (e.g. Cushing's, acromegaly, phaeochromocytoma) Drugs (e.g. corticosteroids, atypical antipsychotics, protease inhibitors)
Describe the epidemiology of T2DM
UK Prevalence: 5-10%
Asian, African + Hispanic > risk
Incidence has increased; linked to increasing prevalence of obesity
What is the nature of T2DM at onset? List 6 presenting symptoms of T2DM
Insidious: Polyuria Polydipsia Tiredness HHS Infections (e.g. infected foot ulcers, candidiasis, balanitis) CVS RFs: HTN, hyperlipidaemia + smoking
What do you measure on physical examination of a suspected T2DM patient?
Weight Height BMI Waist circumference BP
What do you check for in suspected T2DM patients on physical examination?
Diabetic foot (ischaemic + neuropathic signs) Skin changes
List 6 signs that occur in diabetic foot
Dry skin Reduced subcutaneous tissue Ulceration Gangrene Charcot's arthropathy Weak foot pulses
List 3 skin changes that may occur in T2DM
Diabetic dermopathy: depressed pigmented scars on shins
Necrobiosis lipoidica diabeticorum: well-demarcated plaques on shins or arms with shiny atrophic surface + red-brown edges
Granuloma annulare: flesh-coloured papules coalescing in rings on the back of hands + fingers
Which 3 criteria can permit diagnosis of T2DM?
Sx of diabetes + random plasma glucose > 11.1 mmol/L
Sx of diabetes + Fasting plasma glucose > 7 mmol/L
2-hour plasma glucose > 11.1 mmol/L after 75 g oral glucose tolerance test
What must be monitored once a diagnosis of T2DM has been made?
HbA1c U+Es Lipid profile eGFR Urine albumin: creatinine ration (detect microalbuminuria)
Describe the stepwise approach in management of T2DM glycemic control
At diagnosis: lifestyle + metformin
If HbA1c > 7% after 3 months: + sulphonylurea or basal insulin
If HbA1c > 7% after 3 months + FBG > 7 mmol/L: add premeal rapid-acting insulin
What is the MOA of sulphonylureas? When are they less often prescribed? Give an example
Stimulate insulin release by blocking ATP K channel on B cells
In jobs where hypos are undesirable e.g. driving
E.g. Glicazide
What is the MOA of Metformin? What are the side effects?
Inhibits hepatic gluconeogenesis
Side effects: GI disturbances, acidosis
What is the MOA of Thiazilodendones? Give an example
PPAR-Y inhibitors which decrease insulin resistance
E.g. Pioglitazone
What is the MOA of GLP1-like agents? Give an example
Used in those where metformin is not having effect. Incretin effect leads to potent insulin sensitising + releasing stimulus.
Exenatide
What can be given as a monotherapy if a patient can’t tolerate insulin?
Sulphonylurea alone
What can be given alongside Metformin and a sulphonylurea?
a Thiazolidinedione
How are complications of T2DM screened for?
Retinopathy: fundoscopy + digital retinal photography.
Nephropathy: U+Es
Neuropathy: diabetic foot examination, microfilament testing, vibration sensing, foot hygiene. Manage painful neuropathy with gabapentine.
Vascular disease: CVS + foot pulse exam
Diabetic foot: educate on risks + prevention. Diabetic shoes + podiatric assessment. X ray for osteomyelitis. Swab for infection
What does a T2DM patient need educating about?
CVS risks. Should start on statin + lifestyle modification
Specific information in pregnancy + administration of insulin (ie changing injection site to prevent lipoatrophy)
What acronym can be used for managing T2DM patients?
INFORM Information Nutrition Foot education Organizations Recognition of hypos Monitoring CBG
What side effects may be seen as a result of taking insulin?
Weight gain
Fat hypertrophy at insulin injection sites
Hypoglycaemia- Nausea, tremor, confusion
What may mask an overdose of insulin?
B blockers
Autonomic neuropathy
Adaptation to recurrent episode
What may be caused by illness in T2DM? What are 9 symptoms and signs of this?
Hyperosmolar Hyperglycaemic state: Confusion Polyuria Polydipsia Weakness Weight loss Tachycardia Dry mucous membranes Poor skin turgor Hypotension
What is the biochemistry in HHS?
High Na+
High glucose
High osmolality
No acidosis
List 9 possible neuropathic complications in T2DM
Distal symmetrical sensory neuropathy Painful neuropathy Carpel tunnel syndrome Diabetic amyotrophy Mononeuritis Autonomic neuropathy Gastroparesis (abdominal pain, N + V) Impotence Urinary retention
List 5 possible nephropathic complications in T2DM
Microabuminuria Proteinuria Renal failure Prone to UTI Renal papillary necrosis
List 5 possible retinopathic complications in T2DM
Background: hard exudates, dots + blots Pre-proliferative: cotton wool spots Proliferative: visible new vessels Maculopathy Prone to glaucoma, cataracts + transient visual loss
List 3 possible macrovascular complications in T2DM
Ischaemic heart disease
Stroke
Peripheral vascular disease
Describe the prognosis in T2DM
Good prognosis with good control (esp. at start)
“Legacy effect”: benefits persist years after tight control
How can pre-diabetes be diagnosed?
FBG + oral GT test:
Impaired Fasting Glucose (IFG) = FBG 5.6-6.9 mmol/L
Impaired Glucose Tolerance (IGT) = plasma glucose level of 7.8-11.0 mmol/L measured 2 hrs after a 75g OGTT
IFG/ IGT increases risk of developing T2DM
What is the aetiology of microvascular complications in T2DM? List 3 examples
Glycosylation of basement membrane proteins leads to “leaky” capillaries
Retinopathy
Nephropathy
Neuropathy
What is the aetiology of macrovascular complications in T2DM? List 3 examples
Dyslipidaemia HTN IHD CVD Peripheral gangrene
