@article {1057, title = {Clinical and subclinical cardiovascular disease and kidney function decline in the elderly.}, journal = {Atherosclerosis}, volume = {204}, year = {2009}, month = {2009 May}, pages = {298-303}, abstract = {

OBJECTIVE: Kidney function decline in elderly persons may be the result of microvascular atherosclerosis. As a proxy for the renovascular system, we evaluated the association of clinical and subclinical cardiovascular disease (CVD) with kidney function decline.

METHODS: This study included 4380 subjects from the Cardiovascular Health Study, a longitudinal, community-based cohort of persons aged >or=65 from 4 U.S. communities. Creatinine and cystatin C were measured at baseline, year 3, and year 7; eligible subjects had at least two measures. Creatinine-based estimated glomerular filtration rate (eGFR(creat)) was calculated using the MDRD equation. Rapid kidney function decline was defined as an annual eGFR loss >3 mL/min/1.73 m(2). Predictors of rapid kidney decline included prevalent and subclinical measures of CVD.

RESULTS: Mean decline in eGFR(creat) was 0.4+/-2.6/year; 714 (16\%) had rapid progression. In multivariate models adjusted for demographics, cardiovascular risk factors, and inflammation, prevalent stroke (OR, 95\% CI: 1.55, 1.16-2.08) and heart failure (OR, 95\% CI: 1.80, 1.40-2.31) were independent predictors of rapid kidney decline. Among persons without clinical CV, the subclinical disease measures ankle-arm index <0.9 (OR, 95\% CI: 1.67, 1.25-2.24), common carotid intima-media thickness (>or=1.14 mm) (OR, 95\% CI: 1.52, 1.12-2.06) and internal carotid intima-media thickness (>1.82 mm) (OR, 95\% CI: 1.50, 1.12-2.02) had independent associations with rapid kidney function decline. Results were similar using cystatin C.

CONCLUSION: Clinical atherosclerosis and heart failure and subclinical measures of CVD have independent associations with kidney function decline progression in the elderly, suggesting an underlying role of renal atherosclerosis.

}, keywords = {Age Factors, Aged, Atherosclerosis, Cardiovascular Diseases, Creatinine, Cystatin C, Female, Glomerular Filtration Rate, Heart Failure, Humans, Kidney, Kidney Diseases, Linear Models, Longitudinal Studies, Male, Odds Ratio, Risk Assessment, Risk Factors, Time Factors, United States}, issn = {1879-1484}, doi = {10.1016/j.atherosclerosis.2008.08.016}, author = {Shlipak, Michael G and Katz, Ronit and Kestenbaum, Bryan and Fried, Linda F and Siscovick, David and Sarnak, Mark J} } @article {1110, title = {Cystatin C, albuminuria, and mortality among older adults with diabetes.}, journal = {Diabetes Care}, volume = {32}, year = {2009}, month = {2009 Oct}, pages = {1833-8}, abstract = {

OBJECTIVE: Albuminuria and impaired glomerular filtration rate (GFR) are each associated with poor health outcomes among individuals with diabetes. Joint associations of albuminuria and impaired GFR with mortality have not been comprehensively evaluated in this population.

RESEARCH DESIGN AND METHODS: This is a cohort study among Cardiovascular Health Study participants with diabetes, mean age 78 years. GFR was estimated using serum cystatin C and serum creatinine. Albumin-to-creatinine ratio (ACR) was measured in single-voided urine samples.

RESULTS: Of 691 participants, 378 died over 10 years of follow-up. Cystatin C-estimated GFR <60 ml/min per 1.73 m(2), creatinine-based estimated GFR <60 ml/min per 1.73 m(2), and urine ACR > or =30 mg/g were each associated with increased mortality risk with hazard ratios of 1.73 (95\% CI 1.37-2.18), 1.54 (1.21-1.97), and 1.73 (1.39-2.17), respectively, adjusting for age, sex, race, diabetes duration, hypoglycemic medications, hypertension, BMI, smoking, cholesterol, lipid-lowering medications, prevalent cardiovascular disease (CVD), and prevalent heart failure. Cystatin C-estimated GFR and urine ACR were additive in terms of mortality risk. Cystatin C-estimated GFR predicted mortality more strongly than creatinine-based estimated GFR.

CONCLUSIONS: Albuminuria and impaired GFR were independent, additive risk factors for mortality among older adults with diabetes. These findings support current recommendations to regularly assess both albuminuria and GFR in the clinical care of patients with diabetes; a focus on interventions to prevent or treat CVD in the presence of albuminuria, impaired GFR, or both; and further consideration of cystatin C use in clinical care.

}, keywords = {Aged, Aged, 80 and over, Albuminuria, Creatinine, Cystatin C, Diabetes Mellitus, Female, Glomerular Filtration Rate, Humans, Kidney Function Tests, Male, Risk Factors}, issn = {1935-5548}, doi = {10.2337/dc09-0191}, author = {de Boer, Ian H and Katz, Ronit and Cao, Jie J and Fried, Linda F and Kestenbaum, Bryan and Mukamal, Ken and Rifkin, Dena E and Sarnak, Mark J and Shlipak, Michael G and Siscovick, David S} } @article {1204, title = {Common genetic determinants of vitamin D insufficiency: a genome-wide association study.}, journal = {Lancet}, volume = {376}, year = {2010}, month = {2010 Jul 17}, pages = {180-8}, abstract = {

BACKGROUND: Vitamin D is crucial for maintenance of musculoskeletal health, and might also have a role in extraskeletal tissues. Determinants of circulating 25-hydroxyvitamin D concentrations include sun exposure and diet, but high heritability suggests that genetic factors could also play a part. We aimed to identify common genetic variants affecting vitamin D concentrations and risk of insufficiency.

METHODS: We undertook a genome-wide association study of 25-hydroxyvitamin D concentrations in 33 996 individuals of European descent from 15 cohorts. Five epidemiological cohorts were designated as discovery cohorts (n=16 125), five as in-silico replication cohorts (n=9367), and five as de-novo replication cohorts (n=8504). 25-hydroxyvitamin D concentrations were measured by radioimmunoassay, chemiluminescent assay, ELISA, or mass spectrometry. Vitamin D insufficiency was defined as concentrations lower than 75 nmol/L or 50 nmol/L. We combined results of genome-wide analyses across cohorts using Z-score-weighted meta-analysis. Genotype scores were constructed for confirmed variants.

FINDINGS: Variants at three loci reached genome-wide significance in discovery cohorts for association with 25-hydroxyvitamin D concentrations, and were confirmed in replication cohorts: 4p12 (overall p=1.9x10(-109) for rs2282679, in GC); 11q12 (p=2.1x10(-27) for rs12785878, near DHCR7); and 11p15 (p=3.3x10(-20) for rs10741657, near CYP2R1). Variants at an additional locus (20q13, CYP24A1) were genome-wide significant in the pooled sample (p=6.0x10(-10) for rs6013897). Participants with a genotype score (combining the three confirmed variants) in the highest quartile were at increased risk of having 25-hydroxyvitamin D concentrations lower than 75 nmol/L (OR 2.47, 95\% CI 2.20-2.78, p=2.3x10(-48)) or lower than 50 nmol/L (1.92, 1.70-2.16, p=1.0x10(-26)) compared with those in the lowest quartile.

INTERPRETATION: Variants near genes involved in cholesterol synthesis, hydroxylation, and vitamin D transport affect vitamin D status. Genetic variation at these loci identifies individuals who have substantially raised risk of vitamin D insufficiency.

FUNDING: Full funding sources listed at end of paper (see Acknowledgments).

}, keywords = {Canada, Chromosomes, Human, Pair 11, Chromosomes, Human, Pair 4, Cohort Studies, Dietary Supplements, Europe, European Continental Ancestry Group, Genetic Predisposition to Disease, Genome-Wide Association Study, Heterozygote, Homozygote, Humans, Immunoassay, International Cooperation, Linkage Disequilibrium, Polymorphism, Single Nucleotide, Seasons, United States, Vitamin D, Vitamin D Deficiency}, issn = {1474-547X}, doi = {10.1016/S0140-6736(10)60588-0}, author = {Wang, Thomas J and Zhang, Feng and Richards, J Brent and Kestenbaum, Bryan and van Meurs, Joyce B and Berry, Diane and Kiel, Douglas P and Streeten, Elizabeth A and Ohlsson, Claes and Koller, Daniel L and Peltonen, Leena and Cooper, Jason D and O{\textquoteright}Reilly, Paul F and Houston, Denise K and Glazer, Nicole L and Vandenput, Liesbeth and Peacock, Munro and Shi, Julia and Rivadeneira, Fernando and McCarthy, Mark I and Anneli, Pouta and de Boer, Ian H and Mangino, Massimo and Kato, Bernet and Smyth, Deborah J and Booth, Sarah L and Jacques, Paul F and Burke, Greg L and Goodarzi, Mark and Cheung, Ching-Lung and Wolf, Myles and Rice, Kenneth and Goltzman, David and Hidiroglou, Nick and Ladouceur, Martin and Wareham, Nicholas J and Hocking, Lynne J and Hart, Deborah and Arden, Nigel K and Cooper, Cyrus and Malik, Suneil and Fraser, William D and Hartikainen, Anna-Liisa and Zhai, Guangju and Macdonald, Helen M and Forouhi, Nita G and Loos, Ruth J F and Reid, David M and Hakim, Alan and Dennison, Elaine and Liu, Yongmei and Power, Chris and Stevens, Helen E and Jaana, Laitinen and Vasan, Ramachandran S and Soranzo, Nicole and Bojunga, J{\"o}rg and Psaty, Bruce M and Lorentzon, Mattias and Foroud, Tatiana and Harris, Tamara B and Hofman, Albert and Jansson, John-Olov and Cauley, Jane A and Uitterlinden, Andr{\'e} G and Gibson, Quince and Jarvelin, Marjo-Riitta and Karasik, David and Siscovick, David S and Econs, Michael J and Kritchevsky, Stephen B and Florez, Jose C and Todd, John A and Dupuis, Jos{\'e}e and Hypp{\"o}nen, Elina and Spector, Timothy D} } @article {1206, title = {Common genetic variants associate with serum phosphorus concentration.}, journal = {J Am Soc Nephrol}, volume = {21}, year = {2010}, month = {2010 Jul}, pages = {1223-32}, abstract = {

Phosphorus is an essential mineral that maintains cellular energy and mineralizes the skeleton. Because complex actions of ion transporters and regulatory hormones regulate serum phosphorus concentrations, genetic variation may determine interindividual variation in phosphorus metabolism. Here, we report a comprehensive genome-wide association study of serum phosphorus concentration. We evaluated 16,264 participants of European ancestry from the Cardiovascular Heath Study, Atherosclerosis Risk in Communities Study, Framingham Offspring Study, and the Rotterdam Study. We excluded participants with an estimated GFR <45 ml/min per 1.73 m(2) to focus on phosphorus metabolism under normal conditions. We imputed genotypes to approximately 2.5 million single-nucleotide polymorphisms in the HapMap and combined study-specific findings using meta-analysis. We tested top polymorphisms from discovery cohorts in a 5444-person replication sample. Polymorphisms in seven loci with minor allele frequencies 0.08 to 0.49 associate with serum phosphorus concentration (P = 3.5 x 10(-16) to 3.6 x 10(-7)). Three loci were near genes encoding the kidney-specific type IIa sodium phosphate co-transporter (SLC34A1), the calcium-sensing receptor (CASR), and fibroblast growth factor 23 (FGF23), proteins that contribute to phosphorus metabolism. We also identified genes encoding phosphatases, kinases, and phosphodiesterases that have yet-undetermined roles in phosphorus homeostasis. In the replication sample, five of seven top polymorphisms associate with serum phosphorous concentrations (P < 0.05 for each). In conclusion, common genetic variants associate with serum phosphorus in the general population. Further study of the loci identified in this study may help elucidate mechanisms of phosphorus regulation.

}, keywords = {Adult, Aged, European Continental Ancestry Group, Female, Fibroblast Growth Factors, Gene Frequency, Genetic Loci, Genetic Variation, Genome-Wide Association Study, Humans, Kidney, Male, Middle Aged, Phosphorus, Polymorphism, Single Nucleotide, Receptors, Calcium-Sensing, Sex Factors, Sodium-Phosphate Cotransporter Proteins, Type IIa}, issn = {1533-3450}, doi = {10.1681/ASN.2009111104}, author = {Kestenbaum, Bryan and Glazer, Nicole L and K{\"o}ttgen, Anna and Felix, Janine F and Hwang, Shih-Jen and Liu, Yongmei and Lohman, Kurt and Kritchevsky, Stephen B and Hausman, Dorothy B and Petersen, Ann-Kristin and Gieger, Christian and Ried, Janina S and Meitinger, Thomas and Strom, Tim M and Wichmann, H Erich and Campbell, Harry and Hayward, Caroline and Rudan, Igor and de Boer, Ian H and Psaty, Bruce M and Rice, Kenneth M and Chen, Yii-Der Ida and Li, Man and Arking, Dan E and Boerwinkle, Eric and Coresh, Josef and Yang, Qiong and Levy, Daniel and van Rooij, Frank J A and Dehghan, Abbas and Rivadeneira, Fernando and Uitterlinden, Andr{\'e} G and Hofman, Albert and van Duijn, Cornelia M and Shlipak, Michael G and Kao, W H Linda and Witteman, Jacqueline C M and Siscovick, David S and Fox, Caroline S} } @article {1177, title = {Cystatin C and sudden cardiac death risk in the elderly.}, journal = {Circ Cardiovasc Qual Outcomes}, volume = {3}, year = {2010}, month = {2010 Mar}, pages = {159-64}, abstract = {

BACKGROUND: Recent studies have demonstrated an association between moderate kidney dysfunction and sudden cardiac death in people with cardiovascular disease.

METHODS AND RESULTS: The study was a longitudinal analysis among 4465 participants from the Cardiovascular Health Study without prevalent cardiovascular disease at baseline. Cystatin C and creatinine were measured from baseline sera. Sudden cardiac death (SCD) was defined as a sudden pulseless condition from a cardiac origin in a previously stable individual that occurred out of the hospital or in the emergency room. The association between cystatin C tertiles and SCD was determined with multivariate Cox proportional hazards. A similar analysis compared SCD incidence across creatinine-based estimated glomerular filtration rate (eGFR) tertiles. Over a median follow-up of 11.2 years, 91 adjudicated SCD events occurred. The annual incidence of SCD events increased across cystatin C tertiles: 10 events per 10 000 person years in tertile 1, 25 events per 10 000 person years in tertile 2, and 32 events per 10 000 person-years in the highest cystatin C tertile. These associations persisted after multivariate adjustment: hazards ratio=2.72; 95\% confidence interval, 1.44 to 5.16 in tertile 2 and hazards ratio=2.67; 95\% confidence interval, 1.33 to 5.35 in tertile 3. After multivariate adjustment, the rate of SCD also increased in a linear distribution across creatinine-based eGFR tertiles: 15 events per 10 000 person-years in tertile 1, 22 events per 10 000 person-years in tertile 2, and 27 events per 10 000 person-years in tertile 3. No significant associations, however, remained between creatinine-based eGFR and SCD after multivariable adjustment.

CONCLUSIONS: Impaired kidney function, as measured by cystatin C, has an independent association with SCD risk among elderly persons without clinical cardiovascular disease.

}, keywords = {Age Factors, Aged, Biomarkers, Chi-Square Distribution, Creatinine, Cystatin C, Death, Sudden, Cardiac, Female, Glomerular Filtration Rate, Humans, Incidence, Kidney Diseases, Longitudinal Studies, Male, Proportional Hazards Models, Risk Assessment, Risk Factors, Time Factors, United States, Up-Regulation}, issn = {1941-7705}, doi = {10.1161/CIRCOUTCOMES.109.875369}, author = {Deo, Rajat and Sotoodehnia, Nona and Katz, Ronit and Sarnak, Mark J and Fried, Linda F and Chonchol, Michel and Kestenbaum, Bryan and Psaty, Bruce M and Siscovick, David S and Shlipak, Michael G} } @article {1230, title = {Chronic kidney disease and the risk of end-stage renal disease versus death.}, journal = {J Gen Intern Med}, volume = {26}, year = {2011}, month = {2011 Apr}, pages = {379-85}, abstract = {

BACKGROUND: Among older adults with chronic kidney disease (CKD), the comparative event rates of end-stage renal disease (ESRD) and cause-specific death are unknown.

OBJECTIVE: To compare the rates of ESRD, cardiovascular and non-cardiovascular death and examine risk factors for ESRD and all-cause mortality in Cardiovascular Health Study (CHS) participants.

DESIGN: The CHS is a longitudinal cohort study of community-dwelling adults aged 65 years and older.

PARTICIPANTS: 1,268 participants with an estimated glomerular filtration rate (eGFR) < 60 ml/min per 1.73 m(2) were followed until the time of first event (ESRD, cardiovascular or non-cardiovascular death) or until March 31, 2003.

MAIN MEASURES: The outcomes were ESRD, cardiovascular- and non-cardiovascular death. Rates of each event were calculated, and a Cox Proportional Hazards Model with a competing risk framework was used to examine risk factors for ESRD as compared with death. Predictors included age, gender, race, BMI, hypertension, diabetes, cardiovascular disease, heart failure, tobacco use, eGFR, and total cholesterol.

KEY RESULTS: During 9.7 years of follow-up, 5\% of the cohort progressed to ESRD, and 61\% of the cohort died. The rate (per 100 person-years) was 0.5 for ESRD and 6.8 for all-cause mortality (3.0 for cardiovascular and 3.8 for non-cardiovascular mortality). In the competing risk framework, lower eGFR, male gender, African-American race, and higher BMI were associated with an increased risk of ESRD.

CONCLUSIONS: Older adults with CKD are 13-fold more likely to die from any cause than progress to ESRD and are 6-fold more likely to die from cardiovascular causes than develop ESRD.

}, keywords = {Aged, Aged, 80 and over, Cause of Death, Cohort Studies, Female, Follow-Up Studies, Humans, Kidney Failure, Chronic, Longitudinal Studies, Male, Prospective Studies, Renal Insufficiency, Chronic, Risk Factors, Treatment Outcome}, issn = {1525-1497}, doi = {10.1007/s11606-010-1511-x}, author = {Dalrymple, Lorien S and Katz, Ronit and Kestenbaum, Bryan and Shlipak, Michael G and Sarnak, Mark J and Stehman-Breen, Catherine and Seliger, Stephen and Siscovick, David and Newman, Anne B and Fried, Linda} } @article {1271, title = {CUBN is a gene locus for albuminuria.}, journal = {J Am Soc Nephrol}, volume = {22}, year = {2011}, month = {2011 Mar}, pages = {555-70}, abstract = {

Identification of genetic risk factors for albuminuria may alter strategies for early prevention of CKD progression, particularly among patients with diabetes. Little is known about the influence of common genetic variants on albuminuria in both general and diabetic populations. We performed a meta-analysis of data from 63,153 individuals of European ancestry with genotype information from genome-wide association studies (CKDGen Consortium) and from a large candidate gene study (CARe Consortium) to identify susceptibility loci for the quantitative trait urinary albumin-to-creatinine ratio (UACR) and the clinical diagnosis microalbuminuria. We identified an association between a missense variant (I2984V) in the CUBN gene, which encodes cubilin, and both UACR (P = 1.1 {\texttimes} 10(-11)) and microalbuminuria (P = 0.001). We observed similar associations among 6981 African Americans in the CARe Consortium. The associations between this variant and both UACR and microalbuminuria were significant in individuals of European ancestry regardless of diabetes status. Finally, this variant associated with a 41\% increased risk for the development of persistent microalbuminuria during 20 years of follow-up among 1304 participants with type 1 diabetes in the prospective DCCT/EDIC Study. In summary, we identified a missense CUBN variant that associates with levels of albuminuria in both the general population and in individuals with diabetes.

}, keywords = {African Continental Ancestry Group, Albuminuria, European Continental Ancestry Group, Genetic Loci, Genetic Predisposition to Disease, Humans, Mutation, Missense, Receptors, Cell Surface}, issn = {1533-3450}, doi = {10.1681/ASN.2010060598}, author = {B{\"o}ger, Carsten A and Chen, Ming-Huei and Tin, Adrienne and Olden, Matthias and K{\"o}ttgen, Anna and de Boer, Ian H and Fuchsberger, Christian and O{\textquoteright}Seaghdha, Conall M and Pattaro, Cristian and Teumer, Alexander and Liu, Ching-Ti and Glazer, Nicole L and Li, Man and O{\textquoteright}Connell, Jeffrey R and Tanaka, Toshiko and Peralta, Carmen A and Kutalik, Zolt{\'a}n and Luan, Jian{\textquoteright}an and Zhao, Jing Hua and Hwang, Shih-Jen and Akylbekova, Ermeg and Kramer, Holly and van der Harst, Pim and Smith, Albert V and Lohman, Kurt and de Andrade, Mariza and Hayward, Caroline and Kollerits, Barbara and T{\"o}njes, Anke and Aspelund, Thor and Ingelsson, Erik and Eiriksdottir, Gudny and Launer, Lenore J and Harris, Tamara B and Shuldiner, Alan R and Mitchell, Braxton D and Arking, Dan E and Franceschini, Nora and Boerwinkle, Eric and Egan, Josephine and Hernandez, Dena and Reilly, Muredach and Townsend, Raymond R and Lumley, Thomas and Siscovick, David S and Psaty, Bruce M and Kestenbaum, Bryan and Haritunians, Talin and Bergmann, Sven and Vollenweider, Peter and Waeber, G{\'e}rard and Mooser, Vincent and Waterworth, Dawn and Johnson, Andrew D and Florez, Jose C and Meigs, James B and Lu, Xiaoning and Turner, Stephen T and Atkinson, Elizabeth J and Leak, Tennille S and Aasar{\o}d, Knut and Skorpen, Frank and Syv{\"a}nen, Ann-Christine and Illig, Thomas and Baumert, Jens and Koenig, Wolfgang and Kr{\"a}mer, Bernhard K and Devuyst, Olivier and Mychaleckyj, Josyf C and Minelli, Cosetta and Bakker, Stephan J L and Kedenko, Lyudmyla and Paulweber, Bernhard and Coassin, Stefan and Endlich, Karlhans and Kroemer, Heyo K and Biffar, Reiner and Stracke, Sylvia and V{\"o}lzke, Henry and Stumvoll, Michael and M{\"a}gi, Reedik and Campbell, Harry and Vitart, Veronique and Hastie, Nicholas D and Gudnason, Vilmundur and Kardia, Sharon L R and Liu, Yongmei and Polasek, Ozren and Curhan, Gary and Kronenberg, Florian and Prokopenko, Inga and Rudan, Igor and Arnl{\"o}v, Johan and Hallan, Stein and Navis, Gerjan and Parsa, Afshin and Ferrucci, Luigi and Coresh, Josef and Shlipak, Michael G and Bull, Shelley B and Paterson, Nicholas J and Wichmann, H-Erich and Wareham, Nicholas J and Loos, Ruth J F and Rotter, Jerome I and Pramstaller, Peter P and Cupples, L Adrienne and Beckmann, Jacques S and Yang, Qiong and Heid, Iris M and Rettig, Rainer and Dreisbach, Albert W and Bochud, Murielle and Fox, Caroline S and Kao, W H L} } @article {1368, title = {Chronic kidney disease, insulin resistance, and incident diabetes in older adults.}, journal = {Clin J Am Soc Nephrol}, volume = {7}, year = {2012}, month = {2012 Apr}, pages = {588-94}, abstract = {

BACKGROUND AND OBJECTIVES: Insulin resistance is a complication of advanced CKD. Insulin resistance is less well characterized in earlier stages of CKD. The response of the pancreatic β cell, effects on glucose tolerance, and risk of diabetes are not clear.

DESIGN, SETTING, PARTICIPANTS, \& MEASUREMENTS: The Cardiovascular Health Study included 4680 adults without baseline diabetes. The Chronic Kidney Disease Epidemiology Collaboration creatinine equation was used to obtain the estimated GFR (eGFR). Insulin resistance was evaluated as fasting insulin concentration. The insulin sensitivity index, β cell function, and glucose tolerance were assessed by oral glucose tolerance testing. Incident diabetes was defined as fasting glucose >=126 mg/dl, nonfasting glucose >=200 mg/dl, or use of glucose-lowering medications.

RESULTS: Mean age was 72.5 years (range, 65-98 years). Mean eGFR was 72.2 (SD 17.1) ml/min per 1.73 m(2). After adjustment, each 10 ml/min per 1.73 m(2) lower eGFR was associated with a 2.2\% higher fasting insulin concentration (95\% confidence interval [CI], 1.4\%, 2.9\%; P<0.001) and a 1.1\% lower insulin sensitivity index (95\% CI, 0.03\%, 2.2\%; P=0.04). Surprisingly, eGFR was associated with an augmented β cell function index (P<0.001), lower 2-hour glucose concentration (P=0.002), and decreased risk of glucose intolerance (P=0.006). Over a median 12 years{\textquoteright} follow-up, 437 participants (9.3\%) developed diabetes. eGFR was not associated with the risk of incident diabetes.

CONCLUSIONS: Among older adults, lower eGFR was associated with insulin resistance. However, with lower eGFR, β cell function was appropriately augmented and risks of impaired glucose tolerance and incident diabetes were not increased.

}, keywords = {Age Factors, Aged, Aged, 80 and over, Biomarkers, Chronic Disease, Creatinine, Diabetes Mellitus, Female, Glomerular Filtration Rate, Glucose Tolerance Test, Health Surveys, Humans, Hypoglycemic Agents, Incidence, Insulin, Insulin Resistance, Insulin-Secreting Cells, Kidney, Kidney Diseases, Linear Models, Male, Proportional Hazards Models, Risk Assessment, Risk Factors, United States}, issn = {1555-905X}, doi = {10.2215/CJN.11861111}, author = {Pham, Hien and Robinson-Cohen, Cassianne and Biggs, Mary L and Ix, Joachim H and Mukamal, Kenneth J and Fried, Linda F and Kestenbaum, Bryan and Siscovick, David S and de Boer, Ian H} } @article {6062, title = {Circulating 25-hydroxyvitamin D is associated with insulin resistance cross-sectionally but not longitudinally in older adults: The Cardiovascular Health Study.}, journal = {Metabolism}, volume = {62}, year = {2013}, month = {2013 Dec}, pages = {1788-94}, abstract = {

BACKGROUND: Despite extensive study, the role of vitamin D in insulin resistance and secretion remains unclear.

OBJECTIVE: To examine the cross-sectional and longitudinal relationships between 25-hydroxyvitamin D (25(OH)D) concentrations and indices of insulin resistance and secretion in older adults.

METHODS AND RESULTS: Among 2134 participants of the Cardiovascular Health Study who were free from cardiovascular disease, we measured serum 25(OH)D concentrations in samples collected in 1992-1993. We examined insulin resistance and secretion using Homeostasis Model Assessment (HOMA) estimates cross-sectionally and among 1469 participants who had repeated HOMA measures four years later (1996-1997). In cross-sectional analysis, each 10 ng/mL increment in 25(OH)D concentration was associated with a 0.09 lower adjusted HOMA-IR [95\% CI (-0.17, -0.02), p=0.01]. However, baseline 25(OH)D concentrations were not associated with change in HOMA-IR over 4 years of follow up (p=0.48). 25(OH)D concentrations were not associated with insulin secretion, as determined by HOMA-β, in either cross-sectional or longitudinal analysis.

CONCLUSIONS: Circulating 25(OH)D concentrations are associated with lower insulin resistance in cross-sectional but not longitudinal analyses. Whether this reflects residual confounding in cross-sectional analyses or the short-term nature of the relationship between vitamin D and insulin sensitivity will require trials with repeated measures of these factors.

}, keywords = {Adiposity, Aged, Anthropometry, Cardiovascular Diseases, Cross-Sectional Studies, Exercise, Female, Humans, Hydroxycholecalciferols, Inflammation, Insulin, Insulin Resistance, Longitudinal Studies, Male, Middle Aged, Obesity, Risk Factors, Surveys and Questionnaires}, issn = {1532-8600}, doi = {10.1016/j.metabol.2013.07.008}, author = {Danziger, John and Biggs, Mary L and Niemi, Matt and Ix, Joachim H and Kizer, Jorge R and Djouss{\'e}, Luc and de Boer, Ian H and Siscovick, David S and Kestenbaum, Bryan and Mukamal, Kenneth J} } @article {9251, title = {Clonal Hematopoiesis of Indeterminate Potential and Kidney Function Decline in the General Population.}, journal = {Am J Kidney Dis}, year = {2022}, month = {2022 Oct 11}, abstract = {

RATIONALE \& OBJECTIVE: Clonal hematopoiesis of indeterminate potential (CHIP), defined by the age-related ontogenesis of expanded leukemogenic variants indicative of a genetically distinct clonal leukocyte population, is associated with risk of hematologic malignancy and cardiovascular disease. In experimental models, recapitulation of CHIP promotes kidney interstitial fibrosis with direct tissue infiltration of donor macrophages. We tested the hypothesis that CHIP is associated with kidney function decline in the general population.

STUDY DESIGN: Cohort study.

SETTING \& PARTICIPANTS: 12,004 individuals from 3 community-based cohorts in the TOPMed Consortium.

EXPOSURE: CHIP status from whole-genome sequences obtained from DNA extracted from peripheral blood.

OUTCOME: Risk of 30\% decline in estimated glomerular filtration rate (eGFR) and percent eGFR decline per year during the follow-up period.

ANALYTICAL APPROACH: Cox proportional hazards models for 30\% eGFR decline end point and generalized estimating equations for annualized relative change in eGFR with meta-analysis. Study-specific estimates were combined using fixed-effect meta-analysis.

RESULTS: The median baseline eGFR was 84mL/min/1.73m. The prevalence of CHIP was 6.6\%, 9.0\%, and 12.2\% in persons aged 50-60, 60-70, and>70 years, respectively. Over a median follow-up period of 8 years, for the 30\% eGFR outcome 205 events occurred among 1,002 CHIP carriers (2.1 events per 100 person-years) and 2,041 events in persons without CHIP (1.7 events per 100 person-years). In meta-analysis, CHIP was associated with greater risk of a 30\% eGFR decline (17\% [95\% CI, 1\%-36\%] higher; P=0.04). Differences were not observed between those with baseline eGFR above or below 60mL/min/1.73m, of age above or below 60 years, or with or without diabetes.

LIMITATIONS: Small number of participants with moderate-to-advanced kidney disease and restricted set of CHIP driver variants.

CONCLUSIONS: We report an association between CHIP and eGFR decline in 3 general population cohorts without known kidney disease. Further studies are needed to investigate this novel condition and its potential impact among individuals with overt kidney disease.

}, issn = {1523-6838}, doi = {10.1053/j.ajkd.2022.08.014}, author = {Kestenbaum, Bryan and Bick, Alexander G and Vlasschaert, Caitlyn and Rauh, Michael J and Lanktree, Matthew B and Franceschini, Nora and Shoemaker, Moore B and Harris, Raymond C and Psaty, Bruce M and K{\"o}ttgen, Anna and Natarajan, Pradeep and Robinson-Cohen, Cassianne} } @article {9386, title = {Clonal Hematopoiesis of Indeterminate Potential is Associated with Acute Kidney Injury.}, journal = {medRxiv}, year = {2023}, month = {2023 May 17}, abstract = {

Age is a predominant risk factor for acute kidney injury (AKI), yet the biological mechanisms underlying this risk are largely unknown and to date no genetic mechanisms for AKI have been established. Clonal hematopoiesis of indeterminate potential (CHIP) is a recently recognized biological mechanism conferring risk of several chronic aging diseases including cardiovascular disease, pulmonary disease and liver disease. In CHIP, blood stem cells acquire mutations in myeloid cancer driver genes such as and and the myeloid progeny of these mutated cells contribute to end-organ damage through inflammatory dysregulation. We sought to establish whether CHIP causes acute kidney injury (AKI). To address this question, we first evaluated associations with incident AKI events in three population-based epidemiology cohorts (N = 442,153). We found that CHIP was associated with a greater risk of AKI (adjusted HR 1.26, 95\% CI: 1.19-1.34, p<0.0001), which was more pronounced in patients with AKI requiring dialysis (adjusted HR 1.65, 95\% CI: 1.24-2.20, p=0.001). The risk was particularly high in the subset of individuals where CHIP was driven by mutations in genes other than (HR: 1.49, 95\% CI: 1.37-1.61, p<0.0001). We then examined the association between CHIP and recovery from AKI in the ASSESS-AKI cohort and identified that non- CHIP was more common among those with a non-resolving pattern of injury (HR 2.3, 95\% CI: 1.14-4.64, p = 0.03). To gain mechanistic insight, we evaluated the role of -CHIP to AKI in ischemia-reperfusion injury (IRI) and unilateral ureteral obstruction (UUO) mouse models. In both models, we observed more severe AKI and greater post-AKI kidney fibrosis in -CHIP mice. Kidney macrophage infiltration was markedly increased in -CHIP mice and -CHIP mutant renal macrophages displayed greater pro-inflammatory responses. In summary, this work establishes CHIP as a genetic mechanism conferring risk of AKI and impaired kidney function recovery following AKI via an aberrant inflammatory response in CHIP derived renal macrophages.

}, doi = {10.1101/2023.05.16.23290051}, author = {Vlasschaert, Caitlyn and Robinson-Cohen, Cassianne and Kestenbaum, Bryan and Silver, Samuel A and Chen, Jian-Chun and Akwo, Elvis and Bhatraju, Pavan K and Zhang, Ming-Zhi and Cao, Shirong and Jiang, Ming and Wang, Yinqiu and Niu, Aolei and Siew, Edward and Kramer, Holly J and K{\"o}ttgen, Anna and Franceschini, Nora and Psaty, Bruce M and Tracy, Russell P and Alonso, Alvaro and Arking, Dan E and Coresh, Josef and Ballantyne, Christie M and Boerwinkle, Eric and Grams, Morgan and Lanktree, Matthew B and Rauh, Michael J and Harris, Raymond C and Bick, Alexander G} }