Novel Approaches to Managing Chronic Kidney Disease in Primary Care

Introduction

Chronic kidney disease (CKD) characterizes kidney damage for about three months. The classic sign is proteinuria (protein excretion in urine), but a decreased glomerular filtration rate (GFR) and glomerulonephritis (inflammation of kidney structures called glomeruli) can also occur. The primary care domain under the physician is the prevention, prompt diagnosis, and early management of CKD. Studies estimate that about 20 percent of adults have CKD, and the frequency is rising. As a result, the participation of primary care physicians in patient care and improving disease outcomes is becoming evident. In this respect, research warrants adequate training and education for family physicians in managing CKD and its consequences in primary care. Further, it can provide physicians with optimal knowledge to impart quality care to their CKD patients and improve their quality of life (QoL).

How Can Primary Care Physicians Detect and Prevent Chronic Kidney Disease?

Primary care physicians identify CKD following tests. A challenge for them is to detect and carefully manage patients with gradual or progressive CKD.

1. Managing Risk Factors: A thorough knowledge of the risk factors for CKD development is vital to prevent the disease process.

• Type II Diabetes Mellitus: Type II diabetes mellitus (DM type II) is a prominent risk factor precipitating CKD. All DM patients must have tight glycemic control. The American Diabetic Association (ADA) advises all patients to have an HbA1c (a test to measure glycated hemoglobin of glucose linked to hemoglobin) of 7.0, even in the absence of CKD. Furthermore, diabetes mellitus treatment in CKD patients requires dose modification of the advised drugs.

• Hypertension: Strict control of blood pressure (BP) is mandatory in CKD patient care with the help of angiotensin-converting enzyme (ACE) inhibitors, diuretics, and angiotensin receptor blockers (ARBs).

• Tobacco Abuse: Cigarette smoking can lead to a rapid decline in kidney function regardless of CKD patients. Primary care physicians must encourage smoking cessation. It is because smoking abuse also precipitates cardiovascular disease (CVD).

• Cardiovascular Disease: Studies demonstrate a link between markers of CVD and renal outcomes. Alkaline phosphatase (ALP, a marker raised in CVD) is associated with poor disease outcomes in CKD patients. Hence, these patients must be promptly managed to prevent further complications. Physicians must help patients modify hyperlipidemia due to increased low-density lipoprotein cholesterol (a risk factor) levels.

• Nephrotoxic Drugs: Primary care physicians must review medication lists, including any nephrotoxic (toxic to kidneys) drugs. Over-the-counter (OTC) medications must be evaluated for drug-drug interaction risk and nephrotoxicity, Nonsteroidal anti-inflammatory drugs (NSAIDs) are nephrotoxic, and physicians may underestimate a CKD patient’s usage of these medications.

• The non-modifiable risk factors are age above 60 and a family history of CKD.

1. Screening: Screening all individuals with a single risk factor for CKD is not possible in primary care. Therefore, an alternative is to identify patients according to their CKD risk as part of hypertension or diabetes risk assessment. The National Kidney Foundation (NKF) recommends screening for all patients with DM type II, hypertension, a CKD family history, and age 60, as these are notable risk factors for CKD. Moreover, studies recommended an assessment of GFR and proteinuria as the minimal screening for kidney function in these patients.

What Is the Role of Primary Care Physicians in Managing Chronic Kidney Disease?

With increasing age, GFR falls below a certain level, and by age 70, about 30 percent of these individuals can have CKD. However, most of them do not suffer from progressive CKD and have stable CKD. On the contrary, patients with diabetic nephropathy (a serious kidney condition affecting patients with DM type II) can lose kidney function rapidly and progress toward ESRD (end-stage renal disease, kidneys cease to work in this condition).Primary care has a vital role in differentiating between:

1. Stable CKD: It includes the majority of patients requiring standard management of their BP, blood glucose, drug dosing, and observation of cardiovascular risk. Also, primary care physicians can manage patients above 75 years with advanced CKD (stage III or IV).

2. Progressive CKD: These patients comprise a minority and are at a high risk of progressive CKD. Progressive CKD patients need close monitoring and intensive supervision.

What Is the Recommended Management Practice for Chronic Kidney Disease in Primary Care?

1. Diet and Lifestyle Modifications: Primary care physicians must promote the importance of dietary and lifestyle modifications in lowering cardiovascular risk. Patients must stop smoking, decrease salt consumption, and reduce body mass index (BMI, increased BMI is a risk factor for CKD) through diet and physical activity.

2. Blood Pressure Management: Primary care physicians must encourage patients to manage their BP to recommended targets (130/80 mmHg). BP management reduces CKD progression and reduces cardiovascular event risk. In elderly patients (age more than 70 years), BP < 150/90 is a reasonable target. Physicians must monitor adverse events closely in hypertension (electrolyte disorders, GFR decline, postural hypotension, and side effects of drugs).

3. Diabetes Mellitus Management: Diabetes mellitus management is crucial to targets appropriate to the CKD stage. Due to the significant risk of hypoglycemia (low blood sugar) in the advanced stages of CKD, moderate blood sugar control is appropriate. Also, physicians must closely supervise and adjust antidiabetic drugs accordingly.

4. Monitoring Progressive CKD: Primary care physicians must monitor and manage progressive CKD patients with:

• BP measurement and optimization (with follow-up in the early stage every two to four weeks for optimal BP).

• Laboratory measures of serum creatinine (a kidney function indicator) and GFR every three months.

1. Managing High-Risk Patients: Intensive management of high-risk patients such as those with uncontrolled BP, blood glucose, or rapid loss of kidney function. These patients are at the greatest risk of poor disease outcomes.

When Should a Primary Care Physician Refer a Chronic Kidney Disease Patient to a Specialist?

Primary care clinicians can review the need to refer a patient to a nephrologist based on availability and clinical context.Patients that require referral include:

1. Intrinsic Kidney Disease: Diagnosis and management by a specialist are required for conditions leading to intrinsic kidney diseases such as glomerulonephritis, polycystic kidney disease (PKD, kidney disease with multiple cysts), or interstitial nephritis (inflammation of kidney tubules).

2. Drug-Resistant Hypertension and CKD: CKD and hypertension patients not responding to treatment with four or more antihypertensive drugs.

3. Complicated DM and CKD: Patients with impaired blood glucose control or microvascular complications due to DM type II.

4. Progressive CKD: The specialist focuses on delaying CKD progression. Also, nephrologists address advanced CKD disorders (acidosis, bone mineral disease, anemia of CKD, increased infection risks, and the need for dialysis or kidney transplant).

If primary care physicians are unsure about management, research recommends the use of telephone consultations or ‘virtual’ referrals.

Conclusion

Primary care physicians play a pertinent role in managing chronic kidney disease patients. They also help these patients with appropriate counseling and health interventions. Patients must be educated about the disease process for their active participation. Although a nephrologist's referral is an alternative, primary care physicians should be comfortable diagnosing the condition and providing appropriate care to these patients.