A Study to Evaluate the ePidemiology of anEmia Associated With chroNic Kidney Disease in Patients in Primary Care Using The Stockholm CREAtinine Measurement (SCREAM) Register

Study Overview
=================
Brief Summary
-----------------
The objectives of this analysis is to determine the incidence of anemia occurring in patients with chronic kidney disease (CKD) in primary care (i.e. prior to any eventual referral to nephrology care). This analysis also evaluates patient characteristics, anemia treatment and associated cardiovascular risk.

Detailed Description
-----------------
Data will be derived from the Stockholm CREATinine Measurement (SCREAM) cohort, a repository of laboratory data of individuals residing and accessing healthcare in the region of Stockholm and who underwent a creatinine assessment between 2012 - 2018.

Official Title
-----------------
A Non-interventional Evaluation of the ePidemiology of anEmia Associated With chroNic Kidney Disease in Patients in Primary Care Using The Stockholm CREAtinine Measurement (SCREAM) Register

Conditions
-----------------
Chronic Kidney Disease

Intervention / Treatment
-----------------
* Other: Non-interventional


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Patient entered in SCREAM between 2012 and 2018 With two consecutive plasma-creatinine test(s) indicating an estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m^2 With at least one eligible Hb after eGFR < 60 mL/min/1.73 m^2. The date of the first eligible Hb test is the study entry point/index date of the study. Exclusion Criteria: Patient who has had a recent pregnancy or childbirth (issued diagnosis within 2 years prior to index date). Patient with ongoing/recent cancer (diagnosed within the previous 3 years), haematological diseases or leukaemia. Patient with chronic infections (hepatitis, tuberculosis, or human immunodeficiency virus [HIV]); note by definition chronic infections are chronic and look back period will be to 1997. Patients with anemia at baseline (index date), defined by an anemia diagnosis in the year prior, a baseline Hb value within the anemia range according to the WHO definition, or the presence of a recent dispensation of ESA or iron (up to six months prior). Patient referred to nephrologist within the previous 2 years from cohort entry/ index date.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Non-dialysis dependent patients with CKD stage 3-5<br>A cohort of patients will be created from the Stockholm CREAtinine Measurement (SCREAM) cohort based on the eligibility criteria. | Other: Non-interventional<br>* Epidemiology of anemia associated with chronic kidney disease, rather than to evaluate specific drugs<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence rate of anemia in adults with non-dialysis dependent CKD stage 3-5 in primary care | Anemia will be defined as the composite of: a diagnosis of anemia, a haemoglobin (Hb) measurement within the defined range for anemia followed by iron (oral or intravenous [IV]) or erythropoietin-simulating agent (ESA) treatment within 3 months, a Hb measurement within the defined range for anemia followed by another low Hb measurement >3 months apart. Anemia as an outcome will be defined by current World Health Organization (WHO) definitions (Hb < 12 g/dL or 7.45 mmol/L for female and < 13 g/dL or 8.07 mmol/L for male). The incidence rate of anemia will be calculated as the number of new cases divided by person-time of CKD stage 3-5 patients who were at risk of becoming an incident anemia case. | 6 years at maximum | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Baseline characteristics associated with anemia occurrence in unreferred CKD stage 3-5 patients | The prevalence of different baseline characteristics of interest will be summarized. | On Day 1 | 
| Comorbidities associated with anemia occurrence in unreferred CKD stage 3-5 patients | The prevalence of different comorbidities of interest will be summarized. | On Day 1 | 
| Proportion of patients who initiated anemia treatment after incident of anemia | Anemia treatment initiated within 6 months after development of anemia can include oral iron, IV iron, or erythropoietin-simulating agent (ESA). | 6 months | 
| Correlation of incident anemia and the risk of major adverse cardiac events (MACE) events in patients in anemia exposed period | MACE will be defined as all-cause mortality, non-fatal stroke and non-fatal myocardial infarction. Anemia exposed period is from incident anemia until event or end of follow-up. | 7 years at maximum | 
| Correlation of incident anemia and the risk of major adverse cardiac events (MACE) events in patients in anemia non-exposed period | MACE will be defined as all-cause mortality, non-fatal stroke and non-fatal myocardial infarction. The non-exposed period is from baseline (no anemia) until event or the time of anemia development. | 7 years at maximum | 
| Correlation of incident anemia and the risk of MACE+ in patients in anemia exposed period | MACE+ will be defined as any record defining MACE, plus hospitalization for unstable angina or hospitalization for congestive heart failure. Anemia exposed period is from incident anemia until event or end of follow-up. | 7 years at maximum | 
| Correlation of incident anemia and the risk of MACE+ in patients in non-anemia exposed period | MACE+ will be defined as any record defining MACE, plus hospitalization for unstable angina or hospitalization for congestive heart failure. The non-exposed period is from baseline (no anemia) until event or the time of anemia development. | 7 years at maximum | 
| Correlation of incident anemia and the risk of death in patients with anemia | Proportion of death in patients with anemia | 7 years at maximum | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Chronic kidney disease, SCREAM database