Availability of results from serum creatinine laboratory tests has varied across years and ranges between 67% and 80% of VA patients. By age group, serum creatinine results were available for ~50% of those aged 20-29 (48-59%); slightly more of 30-year-olds (56-65%); 64-74% of 40-year-olds, 74-81% of those aged 50-59; 76-86% of 60-69; and 70-81% of those aged 70+.
Chart Explanation: These charts show percentage of patients with serum creatinine laboratory results by year of observation, and by age and CKD risk factor (gender, race, diabetes, or hypertension) status.
The Veteran’s Affairs (VA) data presented are from a national sample of health care visits to the VA Health System by eligible U. S. veterans. During any given year, ~70% of the outpatient population receives a serum creatinine test. While the demographics of VA Health System users are distinct from the general U.S. population, the VA data allow a ‘snapshot’ of clinical practices across the nation.
National VA data were examined for veterans with at least one outpatient visit during the federal fiscal year. To estimate prevalence of CKD, outpatient serum creatinine laboratory results (averaged if a patient had more than one test during the fiscal year) were used to calculate an estimated glomerular filtration rate (eGFR) for each patient using the CKD-EPI equation, excluding dialysis and transplant patients. Estimated GFR (kidney function) was classified into five CKD categories (eGFR =90, eGFR 60-89, stage 3=eGFR 30-59, stage 4=eGFR 15 to 29, and stage 5 without dialysis=eGFR<15 ml/min/1.73 m² and “eGFR Unmeasured” for those patients without serum creatinine testing. Inpatient serum creatinine data were not used as they would be affected by the presence of acute illnesses. Due to the infrequency of testing, albuminuria was not included in the definition of CKD. Dialysis patients were defined by clinic stop-codes (602-611), outpatient procedure codes for dialysis (CPT4: 90921 and 90925), outpatient diagnosis codes (ICD-9-CM: 585.6, V56, V45.1 and E87.91) and inpatient and outpatient diagnosis codes (ICD-9-CM: 5856) to indicate dialysis. Kidney transplant patients were identified by inpatient and outpatient ICD-9-CM diagnosis code V420 and inpatient procedure and surgery codes (55.69).
This material is the result of work supported with resources and the use of facilities at the Veterans Affairs Ann Arbor Health Care System, Ann Arbor, Michigan.
|Description of Measure||Serum Creatinine laboratory testing practices |
|Type of Data Source||Administrative Data|
|Data Set||VA National Data, using the MedSAS data files|
|Health Care System Data||Yes|
|Regional or National?||National|
|Demographic Group||Patients in VA health system|
|Numerator||Participants in denominator with valid serum creatinine test results (between 0.3 and 15.0 mg/dL) in the data.|
|Denominator||Patients aged >20 who have at least one outpatient visit, within specified age-diabetes status group|
|Primary Data Source Indicator||Serum Creatinine Test (1 or more during year)|
|Primary Indicator Method of Measurement||Laboratory|
|Secondary (1) Variable||Age = (Date of Visit - Date of Birth)/365.25|
|Secondary (1) Indicator Method of Measurement||Outpatient Visit|
|Secondary (2) Variable||Diabetes status determined by ICD-9-CM/ICD-10-CM code, hemoglobin A1c lab (6.5+), glucose lab (200+) and/or prescribed medication (outpatient only).|
|Secondary (2) Indicator Method of Measurement||Outpatient visit, Inpatient visit, laboratory results and Pharmacy data for diabetes medication|
|Secondary (3) Variable||Race/Ethnicity|
|Secondary (3) Indicator Method of Measurement||Outpatient Visit, self-reported|
|Secondary (3) from Medical Record?||Yes|
|Secondary (4) Variable ||Diabetes status|
|Secondary (4) Indicator Method of Measurement||Outpatient visit, Inpatient visit, and Pharmacy data for diabetes medication|
|Secondary (5) Variable ||Hypertension status|
|Secondary (5) Indicator Method of Measurement||Outpatient visit, Inpatient visit, and Pharmacy data for diabetes medication|
|Frequency of Measurement (Primary)||Multiple measurements per patient|
|Period Currently Available||2005–2018|
|Limitations of Indicator||The VA health care system is a closed system – most laboratory requests are processed internally, and payment is generally not dependent upon the presence of a CPT code. Hence procedural codes and serum creatinine lab results do not always correlate.|