CDCES Class 6: Microvascular Complications & Exercise

Flashcards defining core clinical concepts, microvascular screening schedules, diagnostic thresholds, and exercise safety principles from CDCES Class 6.

Microvascular Complications

Complications affecting small blood vessels in diabetes, specifically involving the eyes (retinopathy), kidneys (nephropathy), and nerves (neuropathy).

Macrovascular Complications

Complications affecting large blood vessels in diabetes, specifically involving the heart, brain (stroke), and legs (peripheral artery disease [PAD]).

Type 2 Diabetes Eye Screening Schedule

An initial dilated eye examination recommended at diagnosis, followed by annual examinations.

Type 1 Diabetes Eye Screening Schedule

An initial dilated eye examination recommended within $5$ years of diagnosis, followed by annual examinations.

Proliferative Retinopathy

An advanced stage of diabetic retinopathy characterized by the growth of new, fragile blood vessels on the retina or optic nerve that can bleed and cause retinal detachment.

Anti-VEGF Injections

Pharmacologic treatments (such as Avastin, Lucentis, and Eylea) indicated for macular edema and proliferative retinopathy.

Pan-Retinal Photocoagulation

A laser therapy used to treat proliferative retinopathy that cuts the risk of severe vision loss by over $50\%$.

Pregnancy Eye Exam Timeline

Screening recommended before pregnancy and in the first trimester for women with preexisting type 1 or type 2 diabetes, with potential monitoring every trimester and for $1$ year postpartum.

Urine Albumin-to-Creatinine Ratio (UACR)

A kidney screening test categorized as normal ($< 30\,\text{mg/g}$), moderately increased ($30\text{--}299\,\text{mg/g}$), or severely increased ($\ge 300\,\text{mg/g}$); abnormal results require confirmation with $2$ of $3$ tests over $3\text{--}6$ months.

Healthy Kidney Function Criteria

Kidney parameters defined by an eGFR of $60$ or higher combined with a UACR of less than $30\,\text{mg/g}$.

False-Positive UACR Causes

Confounding factors causing transient elevations in urinary albumin, including exercise within $24$ hours, active infection, fever, heart failure, very high blood glucose, menstruation, and very high blood pressure.

SGLT-2 Inhibitor eGFR Threshold (CKD)

Initiated for chronic kidney disease progression risk reduction when eGFR is at least $20$.

Finerenone eGFR Threshold

A mineralocorticoid receptor antagonist indicated in chronic kidney disease when eGFR is at least $25$.

Nephrology Referral Indications

Consultation indicated when eGFR falls below $30$, or when there is an unclear etiology of kidney disease, difficult clinical management, or rapidly declining kidney function.

CKD Non-Dialysis Protein Goal

A target dietary intake of $0.8\,\text{g/kg/day}$ for stage 3 or higher chronic kidney disease not on dialysis (contrasted with $1.0\text{--}1.2\,\text{g/kg/day}$ for patients receiving dialysis).

Hypertension First-Line Therapy with Albuminuria

An ACE inhibitor or ARB recommended for elevated blood pressure with a UACR of $30\text{--}299\,\text{mg/g}$; requires routine monitoring of serum creatinine and potassium.

Leading Cause of Death in CKD

Cardiovascular disease (CVD), highlighting the cardiorenal connection where a UACR of $30\,\text{mg/g}$ or greater signals increased cardiovascular risk.

CKD Hypoglycemia Mechanism

Impaired insulin clearance resulting from renal dysfunction, as healthy kidneys clear $1/4$ to $1/3$ of circulating insulin.

Monofilament Test

A $10\text{-g}$ filament office examination used to evaluate loss of protective sensation in the diabetic foot.

Tuning Fork Test

An office assessment using a vibrating fork to check large nerve fiber function and vibratory sensation.

Small Fiber Neuropathy

Neuropathy involving small sensory fibers assessed via pinprick and temperature tests, typically presenting with burning pain, allodynia, and a stocking-glove distribution.

Large Fiber Neuropathy

Neuropathy involving large nerve fibers assessed via vibration and reflex testing, typically presenting with impaired balance, loss of reflexes, and claw foot deformities.

Metformin-Induced Neuropathy Mimic

Vitamin B12 deficiency, a treatable cause of neuropathy-like symptoms that should be routinely screened and ruled out in patients taking metformin.

Diabetic Autonomic Neuropathy (DAN)

Autonomic nerve dysfunction manifesting as hypoglycemia unawareness, resting tachycardia, orthostatic hypotension, gastroparesis, bladder dysfunction, abnormal sweating, or erectile dysfunction.

Beta-Blocker Hypoglycemia Masking

The pharmacologic blunting of adrenergic hypoglycemia symptoms such as tremors and tachycardia, often leaving diaphoresis (sweating) as the sole observable warning sign.

ADA ABC Goals

Clinical management targets: A1C $< 7\%$ (Time in Range $70\%$), Blood Pressure $< 130/80\,\text{mmHg}$, LDL $< 70\,\text{mg/dL}$, HDL $> 40\,\text{mg/dL}$, and Triglycerides $< 150\,\text{mg/dL}$.

ADA Adult Exercise Recommendations

At least $150\,\text{min/week}$ of moderate-to-vigorous activity, interrupting prolonged sitting every $30\,\text{min}$, combined with resistance training $2\text{--}3$ times per week.

Exercise Medical Clearance Indications

Formal evaluation required for individuals planning vigorous activity who have preexisting microvascular or macrovascular complications, such as proliferative retinopathy.

Ketone Testing Thresholds for Exercise

Mandatory ketone evaluation when blood glucose exceeds $240\,\text{mg/dL}$ in type 1 diabetes or $300\,\text{mg/dL}$ in type 2 diabetes; exercise is contraindicated if ketones are positive because it worsens hyperglycemia and ketosis.

Exercise-Induced Hyperglycemia

A temporary rise in blood glucose during intense exercise triggered by counter-regulatory hormones (adrenaline, glucagon, cortisol) stimulating hepatic glycogenolysis and gluconeogenesis faster than working muscles utilize glucose.

Late-Onset Exercise Hypoglycemia

A delayed drop in blood glucose occurring $4\text{--}15\,\text{hours}$ after moderate-to-high intensity exercise lasting over $30\,\text{min}$, frequently occurring overnight in individuals with type 1 diabetes.

15-15 Rule

The immediate protocol for hypoglycemia (blood glucose $< 70\,\text{mg/dL}$): ingest $15\,\text{g}$ of fast-acting carbohydrate, wait $15\,\text{minutes}$, and recheck blood glucose; foods high in fat or protein (e.g., cheese) are avoided because they delay glucose absorption.