{"content_id":"5wbwiodqge","slug":"kidney-health-aging-egfr-albumin-test-guide","locale":"en","schema_type":"Article","category":"knowledge_base","category_name":"Knowledge Base","title":"Kidney Health: Aging, Tests, and the 3-Month Rule","summary":"Kidney function may decline with age, but chronic kidney disease is not diagnosed based on age alone. Blood eGFR and urine albumin should be tested together, and abnormalities must persist for at least 3 months.","sponsorship_disclosure":null,"affiliate_disclosure":null,"commerce_disclosure":null,"author":{"name":"Injoys Editorial Team","url":"https://injoys.com/ko/about"},"key_points":["The kidneys remove waste and regulate fluid, electrolyte, and acid-base balance.","Chronic kidney disease is a condition in which abnormalities in kidney structure or function persist for at least 3 months.","Blood eGFR and urine albumin tests reveal different types of kidney damage.","Age-related functional decline and kidney disease requiring treatment must be distinguished through testing.","Kidney function may be impaired even when urine output remains normal."],"content_markdown":"Kidney health is linked not only to waste removal but also to the regulation of body fluids, electrolytes, and blood pressure. Function may decline with age, but chronic kidney disease is not diagnosed based on age alone. Blood eGFR and urine albumin should be assessed together, and abnormalities must be confirmed as persisting for at least 3 months.\n\nBased on the 2024 KDIGO Clinical Practice Guideline for Chronic Kidney Disease\n\n## What the Kidneys Do\n\nThe kidneys filter waste and excess water from the blood. The filtered substances are excreted from the body through urine. Substances the body needs are reabsorbed in the renal tubules. This process is more complex than simply acting as a water purifier.\n\nThe kidneys regulate electrolytes such as sodium and potassium. They are also involved in maintaining the body’s acid-base balance. They participate in blood pressure regulation through renin. They are also involved with hormones needed for red blood cell production and bone health.\n\n- Excretion of waste and drug metabolites\n- Regulation of body fluid volume and blood pressure\n- Regulation of electrolytes such as sodium and potassium\n- Maintenance of acid-base balance\n- Regulation of signals for red blood cell production\n- Activation of vitamin D and support of bone metabolism\n\nWhen kidney function declines severely, waste products can accumulate. Fluid and electrolyte balance can also be disrupted. However, immediately describing this as “contaminated blood” can cause misunderstanding. In clinical practice, reduced function is assessed through test values and symptoms.\n\n## Comparing Kidney Aging and Chronic Kidney Disease\n\nAge-related changes and chronic kidney disease do not mean the same thing. Average filtration function may decline with age. The extent of change varies among individuals depending on their health status. Age alone cannot confirm whether a person has the disease.\n\n| Category | Age-related changes | Abnormalities assessed in chronic kidney disease |\n|---|---|---|\n| Filtration function | May gradually decline with age | Low eGFR persists or worsens rapidly |\n| Urine albumin | May remain within the normal range | Albumin excretion may increase |\n| Duration | Varies greatly among individuals | Abnormality persists for at least 3 months |\n| Accompanying findings | There may be no noticeable symptoms | Hematuria, structural abnormalities, electrolyte abnormalities, and other findings may occur |\n| Assessment method | Age and medical history are reviewed together | Blood and urine tests and imaging studies are assessed comprehensively |\n\nNephrons are the functional units of the kidneys that filter blood. The number of nephrons varies among individuals from birth. Aging and disease can reduce the number of functioning nephrons. The remaining nephrons may compensate for filtration function for some time.\n\nSome health explanations state that people in their 60s have half as many nephrons as people in their 20s. This is not a clinical standard that applies to everyone. Measurement methods and individual differences must also be considered. Age-specific prevalence rates should likewise be examined in light of the surveyed population and the definition used.\n\n## Testing Criteria for Chronic Kidney Disease\n\nChronic kidney disease is a condition in which structural or functional abnormalities persist for at least 3 months. A primary test is creatinine-based eGFR from a blood sample. The urine albumin-to-creatinine ratio is also used. The two tests provide different information about risk.\n\n### eGFR Categories\n\n| Category | eGFR unit: mL/min/1.73㎡ | Meaning |\n|---|---:|---|\n| G1 | At least 90 | Normal or high range |\n| G2 | 60~89 | Mild reduction |\n| G3a | 45~59 | Mild to moderate reduction |\n| G3b | 30~44 | Moderate to severe reduction |\n| G4 | 15~29 | Severe reduction |\n| G5 | Less than 15 | Kidney failure range |\n\nG1 and G2 alone do not confirm chronic kidney disease. Evidence of damage, such as albuminuria or a structural abnormality, is required. A single low eGFR result is also not sufficient for a definitive diagnosis. The effects of acute illness or dehydration must be assessed.\n\n### Urine Albumin Categories\n\n| Category | Urine ACR unit: mg/g | Meaning |\n|---|---:|---|\n| A1 | Less than 30 | Normal to mildly increased |\n| A2 | 30~300 | Moderately increased |\n| A3 | More than 300 | Severely increased |\n\nTesting definitions and classifications can be found in the KDIGO 2024 Clinical Practice Guideline for Chronic Kidney Disease. The original text is available on the KDIGO guideline page and in the published PDF. Test results should be interpreted together with the laboratory reference range. No official wording for direct quotation was provided separately.\n\n## Summary of Testing Needs by Condition\n\nThe need for testing depends more on risk factors and previous results than on age. If risk factors are present, the timing of testing can be discussed with a healthcare professional even when there are no symptoms. If an abnormality has already been found, the timing of repeat testing is crucial. If an acute change is suspected, do not wait 3 months.\n\n| Condition | Items to check | Points to consider when interpreting |\n|---|---|---|\n| Diabetes | eGFR, urine ACR | Assess blood glucose control and albuminuria together |\n| High blood pressure | Blood pressure, eGFR, urine ACR | Review blood pressure medications and fluid status together |\n| Cardiovascular disease | eGFR, electrolytes, urine ACR | Heart and kidney risks affect each other |\n| Family history of kidney disease | Medical history, blood and urine tests | The possibility of a hereditary disorder requires separate evaluation |\n| Frequent use of pain relievers | Medication list, eGFR | Tell the healthcare professional the dosage and duration of use |\n| Older age or low muscle mass | eGFR and clinical condition | Creatinine-based estimates may be inaccurate |\n| Sudden worsening of test values | Repeat testing, urine output, electrolytes | Promptly assess for acute kidney injury |\n\n## Order for Reviewing Kidney Tests\n\nKidney tests should be reviewed by connecting the blood and urine results. Looking at only one value in isolation can cause the underlying reason to be missed. Comparing results with previous tests reveals the rate of change. You can prepare for a medical consultation in the following order.\n\n1. Find the serum creatinine and eGFR on the health screening report.\n2. Check the urinalysis for proteinuria or ACR results.\n3. Record previous test dates and values side by side.\n4. Organize information about diabetes, high blood pressure, and medications.\n5. If there is an abnormality, ask the healthcare professional about the cause and when to repeat the test.\n6. Use follow-up testing to determine whether the abnormality persists for at least 3 months.\n\n## Calculation Example\n\nAge-specific ratios can be compared directly only when they have the same denominator. “One in three people in their 70s” is approximately 33.3%. “One in two people in their 80s” is 50%. The difference between the two rates is approximately 16.7 percentage points.\n\nThis calculation is an example of converting the stated fractions into percentages. It is not a calculation of an individual’s probability of developing the disease. The country and sample associated with these figures have not been verified. To cite them as official statistics, the original report must first be located.\n\n## Common Mistakes and Misconceptions\n\nThe most common misconception is assuming that the kidneys are normal as long as urine is being produced. Urine output may be maintained even when kidney function has declined. Conversely, dehydration or urinary tract obstruction can also contribute to reduced urine output. The cause cannot be distinguished based on urine output alone.\n\n- Concluding that a person has chronic kidney disease after one low eGFR result.\n- Looking only at a normal eGFR without checking for albuminuria.\n- Confirming proteinuria based only on foamy urine.\n- Interpreting all swelling as a kidney problem.\n- Taking health supplements as though they were treatments.\n- Hiding the use of pain relievers and supplements.\n- Dismissing reduced function as inevitable because of older age.\n\nDialysis is not a treatment that begins only after urine production has completely stopped. Symptoms, electrolyte abnormalities, and other factors are considered together. The starting point is not determined by a single eGFR value. Treatment decisions require evaluation by a nephrologist.\n\n## Lifestyle Management to Protect Kidney Health\n\nLifestyle management should focus on reducing additional strain on the kidneys. If you have diabetes, follow your blood glucose management plan. If you have high blood pressure, establish a target blood pressure with your healthcare professional. Do not stop prescribed medications on your own.\n\nReducing salt intake may help manage blood pressure and body fluids. Simply drinking large amounts of water is not appropriate. Fluid restriction may be necessary for heart disease or advanced kidney disease. Individual recommendations should be established through medical consultation.\n\nRegular physical activity supports blood pressure and metabolic health. Smoking increases cardiovascular and kidney risks. For nonprescription pain relievers, check the ingredients and duration of use. Dietary supplements should also be checked for interactions before use.\n\n## The Connection Between Kidney Health and Healthy Life Expectancy\n\nKidney health is linked to healthy life expectancy, during which a person can continue living independently. Kidney disease is assessed together with cardiovascular disease risk. Anemia and abnormalities in bone metabolism can also affect the ability to remain active. The purpose of early detection is to reduce these complications.\n\nManaging test results over time is useful. Record both the absolute eGFR value and the direction of change. Compare urine ACR results from the same periods as well. Including changes in blood pressure and medications can help with clinical interpretation.\n\n## Signs Requiring Prompt Medical Attention\n\nA sudden decrease in urine output or deterioration in overall condition requires prompt evaluation. Medical attention should also be sought quickly if shortness of breath or severe swelling develops. Persistent vomiting and changes in consciousness can also be emergency warning signs. Disease stage should not be estimated from symptoms alone.\n\nContact a medical institution immediately in the following situations.\n\n- A sudden, substantial decrease in urine output\n- Shortness of breath or rapidly developing swelling\n- Persistent dizziness and weakness after severe dehydration\n- Repeated hematuria or visible blood clots\n- Reduced urine output or a generalized rash after taking medication\n- Being notified of an abnormal potassium result\n\n## Frequently Asked Questions\n\nKidney disease may have no symptoms in its early stages. Therefore, blood and urine tests are more useful when risk factors are present. Kidney health should not be judged based on age or the appearance of urine alone. The answers below explain general testing principles.","content_html":"\u003cp\u003eKidney health is linked not only to waste removal but also to the regulation of body fluids, electrolytes, and blood pressure. Function may decline with age, but chronic kidney disease is not diagnosed based on age alone. Blood eGFR and urine albumin should be assessed together, and abnormalities must be confirmed as persisting for at least 3 months.\u003c/p\u003e\n\u003cp\u003eBased on the 2024 KDIGO Clinical Practice Guideline for Chronic Kidney Disease\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#what-the-kidneys-do\" class=\"anchor\" id=\"what-the-kidneys-do\"\u003e\u003c/a\u003eWhat the Kidneys Do\u003c/h2\u003e\n\u003cp\u003eThe kidneys filter waste and excess water from the blood. The filtered substances are excreted from the body through urine. Substances the body needs are reabsorbed in the renal tubules. This process is more complex than simply acting as a water purifier.\u003c/p\u003e\n\u003cp\u003eThe kidneys regulate electrolytes such as sodium and potassium. They are also involved in maintaining the body’s acid-base balance. They participate in blood pressure regulation through renin. They are also involved with hormones needed for red blood cell production and bone health.\u003c/p\u003e\n\u003cul\u003e\n\u003cli\u003eExcretion of waste and drug metabolites\u003c/li\u003e\n\u003cli\u003eRegulation of body fluid volume and blood pressure\u003c/li\u003e\n\u003cli\u003eRegulation of electrolytes such as sodium and potassium\u003c/li\u003e\n\u003cli\u003eMaintenance of acid-base balance\u003c/li\u003e\n\u003cli\u003eRegulation of signals for red blood cell production\u003c/li\u003e\n\u003cli\u003eActivation of vitamin D and support of bone metabolism\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eWhen kidney function declines severely, waste products can accumulate. Fluid and electrolyte balance can also be disrupted. However, immediately describing this as “contaminated blood” can cause misunderstanding. In clinical practice, reduced function is assessed through test values and symptoms.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#comparing-kidney-aging-and-chronic-kidney-disease\" class=\"anchor\" id=\"comparing-kidney-aging-and-chronic-kidney-disease\"\u003e\u003c/a\u003eComparing Kidney Aging and Chronic Kidney Disease\u003c/h2\u003e\n\u003cp\u003eAge-related changes and chronic kidney disease do not mean the same thing. Average filtration function may decline with age. The extent of change varies among individuals depending on their health status. Age alone cannot confirm whether a person has the disease.\u003c/p\u003e\n\u003cdiv class=\"overflow-x-auto\"\u003e\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eCategory\u003c/th\u003e\n\u003cth\u003eAge-related changes\u003c/th\u003e\n\u003cth\u003eAbnormalities assessed in chronic kidney disease\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Category\"\u003eFiltration function\u003c/td\u003e\n\u003ctd data-label=\"Age-related changes\"\u003eMay gradually decline with age\u003c/td\u003e\n\u003ctd data-label=\"Abnormalities assessed in chronic kidney disease\"\u003eLow eGFR persists or worsens rapidly\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Category\"\u003eUrine albumin\u003c/td\u003e\n\u003ctd data-label=\"Age-related changes\"\u003eMay remain within the normal range\u003c/td\u003e\n\u003ctd data-label=\"Abnormalities assessed in chronic kidney disease\"\u003eAlbumin excretion may increase\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Category\"\u003eDuration\u003c/td\u003e\n\u003ctd data-label=\"Age-related changes\"\u003eVaries greatly among individuals\u003c/td\u003e\n\u003ctd data-label=\"Abnormalities assessed in chronic kidney disease\"\u003eAbnormality persists for at least 3 months\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Category\"\u003eAccompanying findings\u003c/td\u003e\n\u003ctd data-label=\"Age-related changes\"\u003eThere may be no noticeable symptoms\u003c/td\u003e\n\u003ctd data-label=\"Abnormalities assessed in chronic kidney disease\"\u003eHematuria, structural abnormalities, electrolyte abnormalities, and other findings may occur\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Category\"\u003eAssessment method\u003c/td\u003e\n\u003ctd data-label=\"Age-related changes\"\u003eAge and medical history are reviewed together\u003c/td\u003e\n\u003ctd data-label=\"Abnormalities assessed in chronic kidney disease\"\u003eBlood and urine tests and imaging studies are assessed comprehensively\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\u003c/div\u003e\n\u003cp\u003eNephrons are the functional units of the kidneys that filter blood. The number of nephrons varies among individuals from birth. Aging and disease can reduce the number of functioning nephrons. The remaining nephrons may compensate for filtration function for some time.\u003c/p\u003e\n\u003cp\u003eSome health explanations state that people in their 60s have half as many nephrons as people in their 20s. This is not a clinical standard that applies to everyone. Measurement methods and individual differences must also be considered. Age-specific prevalence rates should likewise be examined in light of the surveyed population and the definition used.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#testing-criteria-for-chronic-kidney-disease\" class=\"anchor\" id=\"testing-criteria-for-chronic-kidney-disease\"\u003e\u003c/a\u003eTesting Criteria for Chronic Kidney Disease\u003c/h2\u003e\n\u003cp\u003eChronic kidney disease is a condition in which structural or functional abnormalities persist for at least 3 months. A primary test is creatinine-based eGFR from a blood sample. The urine albumin-to-creatinine ratio is also used. The two tests provide different information about risk.\u003c/p\u003e\n\u003ch3\u003e\n\u003ca href=\"#egfr-categories\" class=\"anchor\" id=\"egfr-categories\"\u003e\u003c/a\u003eeGFR Categories\u003c/h3\u003e\n\u003cdiv class=\"overflow-x-auto\"\u003e\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eCategory\u003c/th\u003e\n\u003cth\u003eeGFR unit: mL/min/1.73㎡\u003c/th\u003e\n\u003cth\u003eMeaning\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Category\"\u003eG1\u003c/td\u003e\n\u003ctd data-label=\"eGFR unit: mL/min/1.73㎡\"\u003eAt least 90\u003c/td\u003e\n\u003ctd data-label=\"Meaning\"\u003eNormal or high range\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Category\"\u003eG2\u003c/td\u003e\n\u003ctd data-label=\"eGFR unit: mL/min/1.73㎡\"\u003e60~89\u003c/td\u003e\n\u003ctd data-label=\"Meaning\"\u003eMild reduction\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Category\"\u003eG3a\u003c/td\u003e\n\u003ctd data-label=\"eGFR unit: mL/min/1.73㎡\"\u003e45~59\u003c/td\u003e\n\u003ctd data-label=\"Meaning\"\u003eMild to moderate reduction\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Category\"\u003eG3b\u003c/td\u003e\n\u003ctd data-label=\"eGFR unit: mL/min/1.73㎡\"\u003e30~44\u003c/td\u003e\n\u003ctd data-label=\"Meaning\"\u003eModerate to severe reduction\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Category\"\u003eG4\u003c/td\u003e\n\u003ctd data-label=\"eGFR unit: mL/min/1.73㎡\"\u003e15~29\u003c/td\u003e\n\u003ctd data-label=\"Meaning\"\u003eSevere reduction\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Category\"\u003eG5\u003c/td\u003e\n\u003ctd data-label=\"eGFR unit: mL/min/1.73㎡\"\u003eLess than 15\u003c/td\u003e\n\u003ctd data-label=\"Meaning\"\u003eKidney failure range\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\u003c/div\u003e\n\u003cp\u003eG1 and G2 alone do not confirm chronic kidney disease. Evidence of damage, such as albuminuria or a structural abnormality, is required. A single low eGFR result is also not sufficient for a definitive diagnosis. The effects of acute illness or dehydration must be assessed.\u003c/p\u003e\n\u003ch3\u003e\n\u003ca href=\"#urine-albumin-categories\" class=\"anchor\" id=\"urine-albumin-categories\"\u003e\u003c/a\u003eUrine Albumin Categories\u003c/h3\u003e\n\u003cdiv class=\"overflow-x-auto\"\u003e\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eCategory\u003c/th\u003e\n\u003cth\u003eUrine ACR unit: mg/g\u003c/th\u003e\n\u003cth\u003eMeaning\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Category\"\u003eA1\u003c/td\u003e\n\u003ctd data-label=\"Urine ACR unit: mg/g\"\u003eLess than 30\u003c/td\u003e\n\u003ctd data-label=\"Meaning\"\u003eNormal to mildly increased\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Category\"\u003eA2\u003c/td\u003e\n\u003ctd data-label=\"Urine ACR unit: mg/g\"\u003e30~300\u003c/td\u003e\n\u003ctd data-label=\"Meaning\"\u003eModerately increased\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Category\"\u003eA3\u003c/td\u003e\n\u003ctd data-label=\"Urine ACR unit: mg/g\"\u003eMore than 300\u003c/td\u003e\n\u003ctd data-label=\"Meaning\"\u003eSeverely increased\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\u003c/div\u003e\n\u003cp\u003eTesting definitions and classifications can be found in the KDIGO 2024 Clinical Practice Guideline for Chronic Kidney Disease. The original text is available on the KDIGO guideline page and in the published PDF. Test results should be interpreted together with the laboratory reference range. No official wording for direct quotation was provided separately.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#summary-of-testing-needs-by-condition\" class=\"anchor\" id=\"summary-of-testing-needs-by-condition\"\u003e\u003c/a\u003eSummary of Testing Needs by Condition\u003c/h2\u003e\n\u003cp\u003eThe need for testing depends more on risk factors and previous results than on age. If risk factors are present, the timing of testing can be discussed with a healthcare professional even when there are no symptoms. If an abnormality has already been found, the timing of repeat testing is crucial. If an acute change is suspected, do not wait 3 months.\u003c/p\u003e\n\u003cdiv class=\"overflow-x-auto\"\u003e\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eCondition\u003c/th\u003e\n\u003cth\u003eItems to check\u003c/th\u003e\n\u003cth\u003ePoints to consider when interpreting\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Condition\"\u003eDiabetes\u003c/td\u003e\n\u003ctd data-label=\"Items to check\"\u003eeGFR, urine ACR\u003c/td\u003e\n\u003ctd data-label=\"Points to consider when interpreting\"\u003eAssess blood glucose control and albuminuria together\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Condition\"\u003eHigh blood pressure\u003c/td\u003e\n\u003ctd data-label=\"Items to check\"\u003eBlood pressure, eGFR, urine ACR\u003c/td\u003e\n\u003ctd data-label=\"Points to consider when interpreting\"\u003eReview blood pressure medications and fluid status together\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Condition\"\u003eCardiovascular disease\u003c/td\u003e\n\u003ctd data-label=\"Items to check\"\u003eeGFR, electrolytes, urine ACR\u003c/td\u003e\n\u003ctd data-label=\"Points to consider when interpreting\"\u003eHeart and kidney risks affect each other\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Condition\"\u003eFamily history of kidney disease\u003c/td\u003e\n\u003ctd data-label=\"Items to check\"\u003eMedical history, blood and urine tests\u003c/td\u003e\n\u003ctd data-label=\"Points to consider when interpreting\"\u003eThe possibility of a hereditary disorder requires separate evaluation\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Condition\"\u003eFrequent use of pain relievers\u003c/td\u003e\n\u003ctd data-label=\"Items to check\"\u003eMedication list, eGFR\u003c/td\u003e\n\u003ctd data-label=\"Points to consider when interpreting\"\u003eTell the healthcare professional the dosage and duration of use\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Condition\"\u003eOlder age or low muscle mass\u003c/td\u003e\n\u003ctd data-label=\"Items to check\"\u003eeGFR and clinical condition\u003c/td\u003e\n\u003ctd data-label=\"Points to consider when interpreting\"\u003eCreatinine-based estimates may be inaccurate\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd data-label=\"Condition\"\u003eSudden worsening of test values\u003c/td\u003e\n\u003ctd data-label=\"Items to check\"\u003eRepeat testing, urine output, electrolytes\u003c/td\u003e\n\u003ctd data-label=\"Points to consider when interpreting\"\u003ePromptly assess for acute kidney injury\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\u003c/div\u003e\n\u003ch2\u003e\n\u003ca href=\"#order-for-reviewing-kidney-tests\" class=\"anchor\" id=\"order-for-reviewing-kidney-tests\"\u003e\u003c/a\u003eOrder for Reviewing Kidney Tests\u003c/h2\u003e\n\u003cp\u003eKidney tests should be reviewed by connecting the blood and urine results. Looking at only one value in isolation can cause the underlying reason to be missed. Comparing results with previous tests reveals the rate of change. You can prepare for a medical consultation in the following order.\u003c/p\u003e\n\u003col\u003e\n\u003cli\u003eFind the serum creatinine and eGFR on the health screening report.\u003c/li\u003e\n\u003cli\u003eCheck the urinalysis for proteinuria or ACR results.\u003c/li\u003e\n\u003cli\u003eRecord previous test dates and values side by side.\u003c/li\u003e\n\u003cli\u003eOrganize information about diabetes, high blood pressure, and medications.\u003c/li\u003e\n\u003cli\u003eIf there is an abnormality, ask the healthcare professional about the cause and when to repeat the test.\u003c/li\u003e\n\u003cli\u003eUse follow-up testing to determine whether the abnormality persists for at least 3 months.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2\u003e\n\u003ca href=\"#calculation-example\" class=\"anchor\" id=\"calculation-example\"\u003e\u003c/a\u003eCalculation Example\u003c/h2\u003e\n\u003cp\u003eAge-specific ratios can be compared directly only when they have the same denominator. “One in three people in their 70s” is approximately 33.3%. “One in two people in their 80s” is 50%. The difference between the two rates is approximately 16.7 percentage points.\u003c/p\u003e\n\u003cp\u003eThis calculation is an example of converting the stated fractions into percentages. It is not a calculation of an individual’s probability of developing the disease. The country and sample associated with these figures have not been verified. To cite them as official statistics, the original report must first be located.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#common-mistakes-and-misconceptions\" class=\"anchor\" id=\"common-mistakes-and-misconceptions\"\u003e\u003c/a\u003eCommon Mistakes and Misconceptions\u003c/h2\u003e\n\u003cp\u003eThe most common misconception is assuming that the kidneys are normal as long as urine is being produced. Urine output may be maintained even when kidney function has declined. Conversely, dehydration or urinary tract obstruction can also contribute to reduced urine output. The cause cannot be distinguished based on urine output alone.\u003c/p\u003e\n\u003cul\u003e\n\u003cli\u003eConcluding that a person has chronic kidney disease after one low eGFR result.\u003c/li\u003e\n\u003cli\u003eLooking only at a normal eGFR without checking for albuminuria.\u003c/li\u003e\n\u003cli\u003eConfirming proteinuria based only on foamy urine.\u003c/li\u003e\n\u003cli\u003eInterpreting all swelling as a kidney problem.\u003c/li\u003e\n\u003cli\u003eTaking health supplements as though they were treatments.\u003c/li\u003e\n\u003cli\u003eHiding the use of pain relievers and supplements.\u003c/li\u003e\n\u003cli\u003eDismissing reduced function as inevitable because of older age.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eDialysis is not a treatment that begins only after urine production has completely stopped. Symptoms, electrolyte abnormalities, and other factors are considered together. The starting point is not determined by a single eGFR value. Treatment decisions require evaluation by a nephrologist.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#lifestyle-management-to-protect-kidney-health\" class=\"anchor\" id=\"lifestyle-management-to-protect-kidney-health\"\u003e\u003c/a\u003eLifestyle Management to Protect Kidney Health\u003c/h2\u003e\n\u003cp\u003eLifestyle management should focus on reducing additional strain on the kidneys. If you have diabetes, follow your blood glucose management plan. If you have high blood pressure, establish a target blood pressure with your healthcare professional. Do not stop prescribed medications on your own.\u003c/p\u003e\n\u003cp\u003eReducing salt intake may help manage blood pressure and body fluids. Simply drinking large amounts of water is not appropriate. Fluid restriction may be necessary for heart disease or advanced kidney disease. Individual recommendations should be established through medical consultation.\u003c/p\u003e\n\u003cp\u003eRegular physical activity supports blood pressure and metabolic health. Smoking increases cardiovascular and kidney risks. For nonprescription pain relievers, check the ingredients and duration of use. Dietary supplements should also be checked for interactions before use.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#the-connection-between-kidney-health-and-healthy-life-expectancy\" class=\"anchor\" id=\"the-connection-between-kidney-health-and-healthy-life-expectancy\"\u003e\u003c/a\u003eThe Connection Between Kidney Health and Healthy Life Expectancy\u003c/h2\u003e\n\u003cp\u003eKidney health is linked to healthy life expectancy, during which a person can continue living independently. Kidney disease is assessed together with cardiovascular disease risk. Anemia and abnormalities in bone metabolism can also affect the ability to remain active. The purpose of early detection is to reduce these complications.\u003c/p\u003e\n\u003cp\u003eManaging test results over time is useful. Record both the absolute eGFR value and the direction of change. Compare urine ACR results from the same periods as well. Including changes in blood pressure and medications can help with clinical interpretation.\u003c/p\u003e\n\u003ch2\u003e\n\u003ca href=\"#signs-requiring-prompt-medical-attention\" class=\"anchor\" id=\"signs-requiring-prompt-medical-attention\"\u003e\u003c/a\u003eSigns Requiring Prompt Medical Attention\u003c/h2\u003e\n\u003cp\u003eA sudden decrease in urine output or deterioration in overall condition requires prompt evaluation. Medical attention should also be sought quickly if shortness of breath or severe swelling develops. Persistent vomiting and changes in consciousness can also be emergency warning signs. Disease stage should not be estimated from symptoms alone.\u003c/p\u003e\n\u003cp\u003eContact a medical institution immediately in the following situations.\u003c/p\u003e\n\u003cul\u003e\n\u003cli\u003eA sudden, substantial decrease in urine output\u003c/li\u003e\n\u003cli\u003eShortness of breath or rapidly developing swelling\u003c/li\u003e\n\u003cli\u003ePersistent dizziness and weakness after severe dehydration\u003c/li\u003e\n\u003cli\u003eRepeated hematuria or visible blood clots\u003c/li\u003e\n\u003cli\u003eReduced urine output or a generalized rash after taking medication\u003c/li\u003e\n\u003cli\u003eBeing notified of an abnormal potassium result\u003c/li\u003e\n\u003c/ul\u003e\n\u003ch2\u003e\n\u003ca href=\"#frequently-asked-questions\" class=\"anchor\" id=\"frequently-asked-questions\"\u003e\u003c/a\u003eFrequently Asked Questions\u003c/h2\u003e\n\u003cp\u003eKidney disease may have no symptoms in its early stages. Therefore, blood and urine tests are more useful when risk factors are present. Kidney health should not be judged based on age or the appearance of urine alone. The answers below explain general testing principles.\u003c/p\u003e\n","tags":["Kidney health","Chronic kidney disease","Health Screening","Kidney function","Healthy aging"],"faqs":[{"question":"If I urinate normally, does that mean my kidney function is normal?","answer":"Filtration function can decline even if urine output is maintained. Blood eGFR and urine albumin tests should be checked together."},{"question":"If my eGFR is less than 60, does that immediately mean I have chronic kidney disease?","answer":"A diagnosis is not confirmed based on a single result. It is necessary to determine whether the abnormality persists for at least 3 months and to consider the effects of acute illness or dehydration."},{"question":"Can I have kidney disease even if my eGFR is normal?","answer":"It may be possible if albuminuria or structural abnormalities are present. In the G1 or G2 range, other markers of kidney damage are needed for diagnosis."},{"question":"Does foamy urine mean proteinuria?","answer":"Foam can also be affected by the speed or concentration of urine. Recurrent foamy urine should be evaluated with an objective test such as a urine ACR."},{"question":"Is all age-related decline in kidney function normal?","answer":"Average eGFR may decrease with age, but not every decline is normal. The rate of change, albuminuria, and comorbidities should be evaluated together."},{"question":"Should I drink a lot of water for kidney health?","answer":"Not everyone needs to drink a lot of water. If you have heart disease or advanced kidney disease, you should determine your fluid intake with your healthcare team."},{"question":"Which kidney tests should be done together?","answer":"Generally, serum creatinine-based eGFR and the urine albumin-to-creatinine ratio are evaluated together. Urinalysis, electrolyte tests, and imaging tests may be added if necessary."},{"question":"If my kidney function is low, will I need dialysis right away?","answer":"The need for dialysis is not determined by eGFR alone. It is assessed comprehensively based on symptoms, fluid status, electrolyte abnormalities, and response to treatment."}],"sources":[{"url":"https://kdigo.org/wp-content/uploads/2024/03/KDIGO-2024-CKD-Guideline.pdf","title":"KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease","type":"source"},{"url":"https://www.niddk.nih.gov/health-information/kidney-disease/kidneys-how-they-work","title":"NIDDK Your Kidneys \u0026 How They Work","type":"source"},{"url":"https://www.cdc.gov/kidney-disease/about/index.html","title":"CDC About Chronic Kidney Disease","type":"source"},{"url":"https://www.kidney.org/kidney-topics/estimated-glomerular-filtration-rate-egfr","title":"National Kidney Foundation Estimated Glomerular Filtration Rate","type":"data_point"}],"images":[{"id":1238,"url":"https://injoys.com/rails/active_storage/blobs/proxy/eyJfcmFpbHMiOnsiZGF0YSI6MTc2NTEsInB1ciI6ImJsb2JfaWQifX0=--a463af328cdaeda59f5de172aaedf1c532292a60/ai-4eef17b5.webp","is_representative":true,"generation_method":"ai_photo","license":"ai_generated","mime_type":"image/webp","translations":{"ko":{"alt":"진료실에서 소변 용기와 혈액 검체를 앞에 두고 의료진과 상담하는 고령 여성","caption":"고령 여성이 콩팥 관련 안내문이 있는 진료실에서 의료진과 검사에 관해 상담하고 있다.","description":null},"en":{"alt":"Older woman consulting a clinician with urine and blood samples on a tray","caption":"An older woman discusses testing with a clinician in an exam room displaying kidney information.","description":null},"ja":{"alt":"尿容器と血液検体を前に医療従事者と話す高齢女性","caption":"高齢女性が腎臓の資料が掲示された診察室で検査について相談している。","description":null},"es":{"alt":"Mujer mayor hablando con una profesional de salud junto a muestras de orina y sangre","caption":"Una mujer mayor consulta sobre pruebas en una sala con información sobre los riñones.","description":null},"id":{"alt":"Perempuan lansia berbicara dengan tenaga medis di depan sampel urine dan darah","caption":"Seorang perempuan lansia berkonsultasi tentang pemeriksaan di ruang dengan informasi ginjal.","description":null},"pt":{"alt":"Mulher idosa conversa com profissional de saúde diante de amostras de urina e sangue","caption":"Uma mulher idosa conversa sobre exames em uma sala com informações sobre os rins.","description":null},"zh-hant":{"alt":"年長女性在診間與醫護人員交談，桌上放著尿液容器和血液檢體","caption":"年長女性在張貼腎臟資訊的診間與醫護人員討論檢查。","description":null},"de":{"alt":"Ältere Frau spricht mit einer Fachkraft vor Urin- und Blutproben auf einem Tablett","caption":"Eine ältere Frau bespricht Untersuchungen in einem Behandlungsraum mit Niereninformationen.","description":null}}},{"id":1239,"url":"https://injoys.com/rails/active_storage/blobs/proxy/eyJfcmFpbHMiOnsiZGF0YSI6MTc2NTcsInB1ciI6ImJsb2JfaWQifX0=--e71a0c29ed414cccdcbe0d64070c9f4a30d82ec7/ai-8dda18ca.webp","is_representative":false,"generation_method":"ai_image","license":"ai_generated","mime_type":"image/webp","translations":{"ko":{"alt":"콩팥 모형과 혈액·소변 검체, 검사표, 연속된 달력, 모래시계가 놓인 의료 일러스트","caption":"콩팥 검사 수치를 3개월 동안 추적하는 과정을 나타낸다.","description":null},"en":{"alt":"Kidneys with blood and urine samples, test charts, calendars, and an hourglass","caption":"The illustration represents tracking kidney test results over three months.","description":null},"ja":{"alt":"腎臓と血液・尿の検体、検査表、連続するカレンダー、砂時計のイラスト","caption":"腎機能の検査値を3か月にわたり追跡する流れを示している。","description":null},"es":{"alt":"Riñones con muestras de sangre y orina, gráficos, calendarios y un reloj de arena","caption":"La ilustración representa el seguimiento de las pruebas renales durante tres meses.","description":null},"id":{"alt":"Ginjal dengan sampel darah dan urine, grafik pemeriksaan, kalender, serta jam pasir","caption":"Ilustrasi ini menunjukkan pemantauan hasil pemeriksaan ginjal selama tiga bulan.","description":null},"pt":{"alt":"Rins com amostras de sangue e urina, gráficos, calendários e uma ampulheta","caption":"A ilustração representa o acompanhamento dos exames renais durante três meses.","description":null},"zh-hant":{"alt":"腎臟、血液與尿液檢體、檢查圖表、連續日曆及沙漏的醫療插圖","caption":"插圖呈現連續三個月追蹤腎功能檢查結果的過程。","description":null},"de":{"alt":"Nieren mit Blut- und Urinproben, Testdiagrammen, Kalendern und einer Sanduhr","caption":"Die Illustration zeigt die Beobachtung von Nierenwerten über drei Monate.","description":null}}}],"published_at":"2026-09-12T16:05:01+09:00","updated_at":"2026-09-12T16:05:01+09:00","license":"cc_by","translation_status":"reviewed","available_locales":["ko","en","ja","es"],"data_locales":["ko","en","ja","es","id","pt","zh-hant","de"],"url":"https://injoys.com/en/articles/kidney-health-aging-egfr-albumin-test-guide"}