Renal Disease

Appendix A: Medical Aspects of Chronic Kidney Disease (CKD) Relevant to LEOs

Definition of CKD: Glomerular filtration rate (GFR) < 60 ml/min and/or urine albumin/creatinine >30 mg/g lasting > 3 months.1

CKD is a complex disease impacting more than 14% of American adults in 2021.2 The number of prevalent CKD patients is likely to rise due to the growing elderly population and the increased number of patients with diabetes and hypertension. A nephrologist infrequently manages the medical needs of CKD patients until renal replacement therapy is required.

Frequent complications associated with CKD include anemia, dyslipidemia, nutritional deficits, cognitive impairment, osteodystrophy, and cardiovascular disease.3 Anemia is a major sequela of CKD and is an independent risk factor for worsening cardiovascular survival, cognitive impairment, and poor quality of life. Cardiovascular causes are responsible for 60% of deaths in patients with CKD. Partial correction of anemia caused significant increases in ejection fraction, decreases in the left ventricular mass index, and increases in general well-being, but did not improve the Mini-Mental State Exam.4 An early study showed that patients with CKD who do not need dialysis have an inverse relation between psychological symptoms and participant income, GFR, and albuminuria.5

CKD is associated with a diminution in the quality of life, emotional health,6 decreased physical functioning,6-10 cognitive functioning,6, 11-13 increased incidence of TIA/CVA,14, 15 cardiovascular disease,6, 16-21 peripheral vascular disease, atrial fibrillation, congestive heart failure (CHF), left ventricular hypertrophy (LVH), and acute coronary ischemic syndrome. Additionally, bleeding and thrombosis have also been identified in CKD patients depending on the stage of CKD.22 Immune dysfunction in CKD is also beginning to be investigated.   

Cardiovascular disease risk23 increases according to the level of albuminuria: The OR is 1.5 in stage 2; 2-4x in stage 3; 4-10 x in stage 4 and 10-50 x in stage 5; and 20-100 x with ESRD.24

The European Guidelines for Cardiac Risk Prevention in 201624 incorporated CKD into their risk model for primary prevention. Persons with GFR < 30 cc/min and/or diabetics with proteinuria are at very high risk with a 10-year risk of cardiac event higher than10%. Those with a GFR of 30-59 cc/min are classified as “high risk” with a 10-year risk of a cardiac event of 5-10%. 

A common thread across most of the studies noted above is the decrease in both physical functioning and cognitive dysfunction as well as the increased risk of strokes and cardiovascular diseases when the GFR falls below 60 ml/min (CKD stage 3). Impaired kidney function and albuminuria are cardiovascular risk factors independent of traditional cardiac risk factors.19, 25 The risk of sudden cardiac death (SDS) has been documented to increase below a GFR of 60 ml/min21 but is especially prominent in persons with a GFR < 40 ml/min18 and just before the initiation of renal replacement therapy16 in stages 4 and 5 of CKD.  

Symptoms of CKD

Clinical symptoms in CKD stages 1 and 2 are unusual but may include symptoms related to underlying diseases such as diabetes mellitus (DM), polycystic kidney disease (PKD), and/or uncontrolled hypertension. Stage 3 disease usually remains asymptomatic but may be associated with peripheral edema, facial edema, shortness of breath, and/or nocturia. Secondary hypertension may also arise at this point and result in symptoms if uncontrolled.26

Stage 4 CKD is commonly associated with increasing symptoms including increased peripheral edema, CHF, fatigue, pruritus, restless extremities, alterations in mental state, memory and concentration disorders, decreased taste and smell, decreased appetite, and/or nausea and vomiting.

Stage 5 CKD (Renal replacement therapy is needed) is associated with symptoms including CHF uremic encephalopathy, hiccups, peripheral neuropathy, bleeding diathesis, pericarditis, sexual dysfunction, weight loss, and electrolyte abnormalities such as hypocalcemia. 

Dialysis therapy itself is associated with lightheadedness, cramps, fatigue, muscle wasting, weight loss, palpitations, and/or chest pain.

CKD is associated with a decrease in quality of life and emotional health, decreased physical functioning and cognitive function, and increased risk of stroke and cardiovascular disease.27 Conditions that can cause acute incapacitation include a decrease in physical functioning, cognitive function, acute stroke, and/or an acute cardiovascular event.