Aims/hypothesis: In a retrospective, observational, cross-sectional, single-centre study, we assessed the prevalence and correlates of different CKD phenotypes (with and without albuminuria) in a large cohort of patients of white ethnicity with type 1 diabetes. Methods: From 2001 to 2009, 408 men and 369 women with type 1 diabetes (age 40.2 ± 11.7 years, diabetes duration 19.4 ± 12.2 years, HbA1c 7.83 ± 1.17% [62.0 ± 12.9 mmol/mol]) were recruited consecutively. Albumin-to-creatinine ratio (ACR) and eGFR (Modification of Diet in Renal Disease) were obtained for all individuals, together with CKD stage. Diabetic retinopathy and peripheral polyneuropathy were detected in 41.5% and 8.1%, respectively, and cardiovascular disease (CVD) occurred in 8.5%. Adjudications of CKD phenotype were made by blinded investigators. Results: Normo- (ACR <3.4), micro- (ACR 3.4–34) or macroalbuminuria (ACR ≥34 mg/mmol) were present in 91.6%, 6.4% and 1.9% of individuals, respectively. eGFR categories 1 (≥90 ml min−1 [1.73 m]−2), 2 (60–89 ml min−1 [1.73 m]−2) and 3 (<60 ml min−1 [1.73 m]−2) were present in 57.3%, 39.0% and 3.7%, respectively. The majority of participants had no CKD (89.4%), while stages 1–2 and ≥3 CKD were detected in 6.8% and 3.7%, respectively. The albuminuric (Alb+) and non-albuminuric (Alb−) phenotypes were present in 12 (41.4%) and 17 (58.6%) individuals with stage ≥3 CKD, respectively. Individuals with an ACR <3.4 mg/mmol were subdivided into those with normal albuminuria (<1.1 mg/mmol; 77.2%) and mildly increased albuminuria (1.1–3.4 mg/mmol; 14.4%), and individuals with stage 2 CKD were subdivided into those with eGFR 75–89 ml min−1 [1.73 m]−2 and 60–74 ml min−1 [1.73 m]−2. ACR <3.4 mg/mmol (88.7%) and even <1.1 mg/mmol (70.4%) were common in individuals with eGFR 60–74 ml min−1 [1.73 m]−2. The prevalence of ACR <1.1 mg/mmol was lower but still significant (34.5%) in those with stage ≥3 CKD. In logistic regression analysis, stages 1–2 and ≥3 CKD were independently associated with age, HbA1c, γ-glutamyltransferase, fibrinogen, hypertension, but not with sex, BMI, smoking, HDL-cholesterol or triacylglycerol. Inclusion of advanced retinopathy removed HbA1c from the model. The CKD Alb+ phenotype correlated with diabetes duration, HbA1c, HDL-cholesterol, fibrinogen and hypertension, while the CKD Alb− phenotype was associated with age and hypertension, but not with diabetes duration, HbA1c and fibrinogen. Conclusions/interpretation: The Alb− CKD phenotype is present in a significant proportion of individuals with type 1 diabetes supporting the hypothesis of two distinct pathways (Alb+ and Alb−) of progression towards advanced kidney disease in type 1 diabetes. These are probably distinct pathways as suggested by different sets of covariates associated with the two CKD phenotypes.
Evidence for two distinct phenotypes of chronic kidney disease in individuals with type 1 diabetes mellitus
PENNO, GIUSEPPE;GAROFOLO, MONIA;DANIELE, GIUSEPPE;LUCCHESI, DANIELA;GIUSTI, LAURA;SANCHO BORNEZ, VERONICA;DARDANO, ANGELA;MICCOLI, ROBERTO;DEL PRATO, STEFANO
2017-01-01
Abstract
Aims/hypothesis: In a retrospective, observational, cross-sectional, single-centre study, we assessed the prevalence and correlates of different CKD phenotypes (with and without albuminuria) in a large cohort of patients of white ethnicity with type 1 diabetes. Methods: From 2001 to 2009, 408 men and 369 women with type 1 diabetes (age 40.2 ± 11.7 years, diabetes duration 19.4 ± 12.2 years, HbA1c 7.83 ± 1.17% [62.0 ± 12.9 mmol/mol]) were recruited consecutively. Albumin-to-creatinine ratio (ACR) and eGFR (Modification of Diet in Renal Disease) were obtained for all individuals, together with CKD stage. Diabetic retinopathy and peripheral polyneuropathy were detected in 41.5% and 8.1%, respectively, and cardiovascular disease (CVD) occurred in 8.5%. Adjudications of CKD phenotype were made by blinded investigators. Results: Normo- (ACR <3.4), micro- (ACR 3.4–34) or macroalbuminuria (ACR ≥34 mg/mmol) were present in 91.6%, 6.4% and 1.9% of individuals, respectively. eGFR categories 1 (≥90 ml min−1 [1.73 m]−2), 2 (60–89 ml min−1 [1.73 m]−2) and 3 (<60 ml min−1 [1.73 m]−2) were present in 57.3%, 39.0% and 3.7%, respectively. The majority of participants had no CKD (89.4%), while stages 1–2 and ≥3 CKD were detected in 6.8% and 3.7%, respectively. The albuminuric (Alb+) and non-albuminuric (Alb−) phenotypes were present in 12 (41.4%) and 17 (58.6%) individuals with stage ≥3 CKD, respectively. Individuals with an ACR <3.4 mg/mmol were subdivided into those with normal albuminuria (<1.1 mg/mmol; 77.2%) and mildly increased albuminuria (1.1–3.4 mg/mmol; 14.4%), and individuals with stage 2 CKD were subdivided into those with eGFR 75–89 ml min−1 [1.73 m]−2 and 60–74 ml min−1 [1.73 m]−2. ACR <3.4 mg/mmol (88.7%) and even <1.1 mg/mmol (70.4%) were common in individuals with eGFR 60–74 ml min−1 [1.73 m]−2. The prevalence of ACR <1.1 mg/mmol was lower but still significant (34.5%) in those with stage ≥3 CKD. In logistic regression analysis, stages 1–2 and ≥3 CKD were independently associated with age, HbA1c, γ-glutamyltransferase, fibrinogen, hypertension, but not with sex, BMI, smoking, HDL-cholesterol or triacylglycerol. Inclusion of advanced retinopathy removed HbA1c from the model. The CKD Alb+ phenotype correlated with diabetes duration, HbA1c, HDL-cholesterol, fibrinogen and hypertension, while the CKD Alb− phenotype was associated with age and hypertension, but not with diabetes duration, HbA1c and fibrinogen. Conclusions/interpretation: The Alb− CKD phenotype is present in a significant proportion of individuals with type 1 diabetes supporting the hypothesis of two distinct pathways (Alb+ and Alb−) of progression towards advanced kidney disease in type 1 diabetes. These are probably distinct pathways as suggested by different sets of covariates associated with the two CKD phenotypes.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
