Introduction
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Kidney Disease Improving Global Outcomes (KDIGO, 2012)
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National Institute for Health and Care Excellence (NICE, 2014)
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Recommendation of the German Society of Nephrology/German Society of Internal Medicine (DGfN/DGIM, 2015) and
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German College of General Practitioners and Family Physicians (DEGAM, 2019).
Methods
Study design and population
Measurements and data analysis
Guideline definition | Study data definition | Referral criteria | |||
---|---|---|---|---|---|
DEGAM | DGfN/DGIM | NICE 2014 | KDIGO | ||
Kidney function | |||||
GFR | eGFR (ml/min) | < 30 or 30–59 b and one of the following criteria | < 45 or 45–59 and one of the following criteria | < 30 or 30–59 and one of the following criteria | < 30 or 30–59 and one of the following criteria |
GFR progression > 5 ml/min / year | mean eGFR reduction > 5 ml/min from first to second follow-up examination | x | |||
GFR progression > 5 ml/min / year or GFR reduction ≥ 25% / year | mean eGFR reduction > 5 ml/min from first to second follow-up examination or mean eGFR reduction of ≥ 25% | x | |||
GFR progression ≥ 15 ml/ min / year or GFR reduction ≥ 25% / year | mean eGFR reduction > 15 ml/min from first to second follow-up examination or mean eGFR reduction of ≥ 25% | x | |||
Hypertension refractory to treatment | |||||
BP > 150 and/or > 90 mmHg and ≥ 3 antihypertensives | BP: mean systolic BP of 2. and 3. measurement Antihypertensives: ATC-codes C02-C09 | x | x | ||
BP > 150 and/or > 90 mmHg and ≥ 4 antihypertensives | BP: mean systolic BP of 2. and 3. measurement Antihypertensives: ATC-codes C02-C09 | x | x | ||
Proteinuria | |||||
Proteinuria > 200 mg/l, subjects with diabetes: > 20 mg/l | Urine albumin dipstick category, subjects with diabetes: urine protein dipstick category | x | |||
Albuminuria ≥ 300 mg/g or ≥ 30 mg/mmol | ACR | x | |||
Proteinuria ≥ 70 mg/mmol and non-diabetic | ACR | x | |||
Albuminuria ≥ 30 mg/g or ≥ 3 mg/mmol | ACR | x | |||
ACR ≥ 30 mg/mmol and haematuria | ACR and urine dipstick category red blood cells + + | x | |||
Haematuria | |||||
Micro- or macrohematuria | urine dipstick category red blood cells + + a | x | x | ||
Haematuria without known urologic cause | urine dipstick category red blood cells + + a | x | |||
Morphologic and structural kidney abnormalities | |||||
Morphologic kidney changes | ICD-10-GM codes • at least one billing code one year prior to study examination of second follow-up (N02.-, N20.-) • at least one billing code five years prior to study examination of second follow-up (N11.-, N13.-, N26.-, N28.-, C64.-, D41.0, Q61.-, Q63.-, I70.1) | x | |||
Kidney stones | ICD-10-GM codes N20.-, at least one billing code one year prior to study examination of second follow-up | x | |||
Renal artery stenosis | ICD-10-GM code I70.1, at least one billing code five years prior to study examination of second follow-up | x | |||
Miscellaneous | |||||
Hypocalcaemia | < 2.12 mmol/l | x | |||
Hyperphosphatemia | > 1.6 mmol/l | x | |||
Abnormalities of serum potassium | Serum potassium < 3.7 mmol/l or > 5.1 mmol/l | x | |||
Inherited kidney disease | ICD-10-GM codes, at least one billing code five years prior to study examination of second follow-up (Q61.-, Q63.-) | x | x | ||
Anaemia | WHO reference values haemoglobin, female: < 7.4 mmol/l, male: < 8.1 mmol/l | x |
Results
Patient characteristics
Characteristic | GFR category G1, G2 (60–89; ≥ 90 ml/min) | GFR category G3a (45–59 ml/min) | GFR category G3b (30–44 ml/min) | GFR category G4 (15–29 ml/min) | GFR category G5 (< 15 ml/min) |
---|---|---|---|---|---|
n = 1737 (90.1%) | n= 137 (7.1%) | n = 42 (2.2%) | n = 9 (0.5%) | n = 2 (0.1%) | |
Female n (%) | 930 (53.5) | 76 (55.5) | 20 (47.6) | 3 (33.3) | 1 (50) |
Age, mean (± SD) (years) | 56.7 (12.9) | 73 (6.7) | 77.5 (8.2) | 80 (8.7) | 65 (14.1) |
Range (years) | 31–89 | 56–93 | 57–90 | 66–89 | 55–75 |
Hypertension > 150 and/or > 90 mmHg, n (%) | 401 (23.1) | 49 (35.8) | 14 (33.3) | 3 (33.3) | 1 (50) |
Diabetes (self-reported), n (%) | 194 (11.2) | 37 (27) | 16 (38.1) | 6 (66.7) | 1 (50) |
Albuminuria ≥ 300 mg/g or ≥ 30 mg/mmol, n (%) | 25 (1.4) | 6 (4.4) | 7 (16.7) | 2 (22.2) | 1 (50) |
Anaemia, n (%) | 104 (6) | 21 (15.3) | 15 (35.7) | 3 (33.3) | 1 (50) |
Abnormalities of serum potassium, n (%) | 84 (4.8) | 15 (11) | 9 (21.4) | 1 (11.1) | 1 (50) |
Hypocalcaemia, n (%) | 71 (4) | 3 (2.2) | 4 (9.5) | 0 (0) | 0 (0) |
Morphologic kidney changes, n (%) | 270 (15.5) | 49 (35.7) | 16 (38.1) | 2 (22.2) | 1 (50) |
Kidney stones, n (%) | 100 (5.8) | 16 (11.7) | 1 (2.4) | 0 (0) | 0 (0) |
Inherited kidney disease, n (%) | 120 (6.9) | 24 (17.5) | 6 (14.3) | 0 (0) | 0 (0) |
Haematuria, n (%) | 97 (5.6) | 10 (7.3) | 3 (7.1) | 2 (22.2) | 0 (0) |
Participants eligible for referral
Guideline (year) | Participants eligible for referral n, (%) | Participants eligible for referral by age category, n (%) | estimated referral costs (€)C according to referral criteria | |
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< 60 yearsa | ≥ 60 yearsb | |||
DGfN/DGIM (2015) | 159/1927 (8.3) | 4 (0.4) | 155 (16.5) | 4,384.48 |
KDIGO (2012) | 148/1927 (7.7) | 4 (0.4) | 144 (15.3) | 4, 080.88 |
NICE (2014) | 103/1927 (5.4) | 3 (0.3) | 100 (10.6) | 2,839.86 |
DEGAM (2019) | 95/1927 (4.9) | 4 (0.4) | 91 (9.7) | 2,618.08 |
KFRE (only) | 15/1927 (0.8) | 3 (0.3) | 12 (1.3) | 411.06 |
NICE 2021 (incl. KFRE) | 104/1927 (5.4) | 4 (0.4) | 100 (10.6) | 2,866.48 |
Patients actually consulting a nephrologist
Estimated population level referral and corresponding costs for Mecklenburg-Vorpommern
Guideline (year) | Eligible for referral by age category n (%) | Referral cost (€a) | Total cost (€a) | ||
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Aged < 60 | Aged ≥ 60 | Aged < 60 | Aged ≥ 60 | ||
DGfN/DGIM (2015) | 2,703 (0.4) | 83,849 (16.5) | 71,953.86 | 2,314,232.40 | 2,386,186.26 |
KDIGO (2012) | 2,703 (0.4) | 77,751 (15.3) | 71,953.86 | 2,145,927.60 | 2,217,881.46 |
NICE (2014) | 2,027 (0.3) | 53,866 (10.6) | 53,958.74 | 1,486,701.60 | 1,540,660.34 |
DEGAM (2019) | 2,703 (0.4) | 49,293 (9.7) | 71,953.86 | 1,360,486.80 | 1,432,440.66 |