Lund University Publications

Shrunken Pore Syndrome in relation to Morbidity and Mortality in the Population-Based Malmö Diet and Cancer Cohort: A Generalized Propensity Score Approach

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Åkesson, Anna ^LU ; Xhakollari, Liana ^LU ; Laucyte-Cibulskiene, Agne ^LU ; Grubb, Anders ^LU ; Larsson, Anders ; Jujic, Amra ^LU ; Magnusson, Martin ^LU ; Christensson, Anders ^LU and Björk, Jonas ^LU

Abstract

Purpose: Glomerular filtration rate (GFR) is used to evaluate kidney function. Creatinine and cystatin C levels C are the two endogenous substances used to estimate GFR (eGFRCR and eGFRCYS). Agreement between the two is reflected by the eGFRCYS/eGFRCR-ratio, and an eGFRCYS/eGFRCR-ratio <0.70 is strongly associated with mortality and morbidity. An explanation is a selective decrease in the filtration of substances of different mass, and this condition is referred to as "Shrunken Pore Syndrome" (SPS). We aim to investigate the prevalence of SPS and its association with morbidity and mortality in a well characterized population-based cohort. Methods: The study population consisted of 5061 individuals from the Malmö Diet and Cancer... (More)

Purpose: Glomerular filtration rate (GFR) is used to evaluate kidney function. Creatinine and cystatin C levels C are the two endogenous substances used to estimate GFR (eGFRCR and eGFRCYS). Agreement between the two is reflected by the eGFRCYS/eGFRCR-ratio, and an eGFRCYS/eGFRCR-ratio <0.70 is strongly associated with mortality and morbidity. An explanation is a selective decrease in the filtration of substances of different mass, and this condition is referred to as "Shrunken Pore Syndrome" (SPS). We aim to investigate the prevalence of SPS and its association with morbidity and mortality in a well characterized population-based cohort. Methods: The study population consisted of 5061 individuals from the Malmö Diet and Cancer cardiovascular cohort (MDC-CC) with baseline examination 1991-1994, and a median follow-up of 25.3 years (IQR=5.7). The eGFRCYS/eGFRCR-ratio was categorized into four groups and used to estimate a generalized propensity score for SPS to adjust for confounding factors. Individuals were matched to create a quartet (one from each eGFRCYS/eGFRCR-ratio category) with similar scores. We related the eGFRCYS/eGFRCR-ratio to all-cause mortality, incident CVD, incident kidney disease, and incident diabetes using Cox proportional hazard models with shared frailty. Results: SPS was detected in 405 individuals (8.0%). The hazard ratio (HR) for all-cause mortality was 1.6 (95% confidence interval [CI] 1.3-2.0) when comparing individuals with SPS to the reference group (eGFRCYS/eGFRCR-ratio≥1.0). For incident kidney disease the association seems to stem from a low eGFRCYS rather than the eGFRCYS/eGFRCR-ratio. For the other two outcomes, robust and statistically significant associations could not be found. Conclusion: SPS was prevalent among middle-aged, generally healthy, individuals and led to markedly higher mortality during follow up. (Less)