@article {1129, title = {Meta-analysis: retinal vessel caliber and risk for coronary heart disease.}, journal = {Ann Intern Med}, volume = {151}, year = {2009}, month = {2009 Sep 15}, pages = {404-13}, abstract = {

BACKGROUND: Retinal vessel caliber may be a novel marker of coronary heart disease (CHD) risk. However, the sex-specific effect, magnitude of association, and effect independent of traditional CHD disease risk factors remain unclear.

PURPOSE: To determine the association between retinal vessel caliber and risk for CHD.

DATA SOURCES: Relevant studies in any language identified through MEDLINE (1950 to June 2009) and EMBASE (1950 to June 2009) databases.

STUDY SELECTION: Studies were included if they examined a general population, measured retinal vessel caliber from retinal photographs, and documented CHD risk factors and incident CHD events.

DATA EXTRACTION: 6 population-based prospective cohort studies provided data for individual participant meta-analysis.

DATA SYNTHESIS: Proportional hazards models, adjusted for traditional CHD risk factors, were constructed for retinal vessel caliber and incident CHD in women and men. Among 22,159 participants who were free of CHD and followed for 5 to 14 years, 2219 (10.0\%) incident CHD events occurred. Retinal vessel caliber changes (wider venules and narrower arterioles) were each associated with an increased risk for CHD in women (pooled multivariable-adjusted hazard ratios, 1.16 [95\% CI, 1.06 to 1.26] per 20-microm increase in venular caliber and 1.17 [CI, 1.07 to 1.28] per 20-microm decrease in arteriolar caliber) but not in men (1.02 [CI, 0.94 to 1.10] per 20-microm increase in venular caliber and 1.02 [CI, 0.95 to 1.10] per 20-microm decrease in arteriolar caliber). Women without hypertension or diabetes had higher hazard ratios.

LIMITATION: Error in the measurement of retinal vessel caliber and Framingham variables was not taken into account.

CONCLUSION: Retinal vessel caliber changes were independently associated with an increased risk for CHD events in women.

}, keywords = {Adult, Aged, Arterioles, Biomarkers, Coronary Disease, Female, Humans, Male, Middle Aged, Proportional Hazards Models, Retinal Vessels, Risk Factors, Sex Factors, Venules}, issn = {1539-3704}, author = {McGeechan, Kevin and Liew, Gerald and Macaskill, Petra and Irwig, Les and Klein, Ronald and Klein, Barbara E K and Wang, Jie Jin and Mitchell, Paul and Vingerling, Johannes R and Dejong, Paulus T V M and Witteman, Jacqueline C M and Breteler, Monique M B and Shaw, Jonathan and Zimmet, Paul and Wong, Tien Y} } @article {1243, title = {Four novel Loci (19q13, 6q24, 12q24, and 5q14) influence the microcirculation in vivo.}, journal = {PLoS Genet}, volume = {6}, year = {2010}, month = {2010 Oct 28}, pages = {e1001184}, abstract = {

There is increasing evidence that the microcirculation plays an important role in the pathogenesis of cardiovascular diseases. Changes in retinal vascular caliber reflect early microvascular disease and predict incident cardiovascular events. We performed a genome-wide association study to identify genetic variants associated with retinal vascular caliber. We analyzed data from four population-based discovery cohorts with 15,358 unrelated Caucasian individuals, who are members of the Cohort for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium, and replicated findings in four independent Caucasian cohorts (n  =  6,652). All participants had retinal photography and retinal arteriolar and venular caliber measured from computer software. In the discovery cohorts, 179 single nucleotide polymorphisms (SNP) spread across five loci were significantly associated (p<5.0{\texttimes}10(-8)) with retinal venular caliber, but none showed association with arteriolar caliber. Collectively, these five loci explain 1.0\%-3.2\% of the variation in retinal venular caliber. Four out of these five loci were confirmed in independent replication samples. In the combined analyses, the top SNPs at each locus were: rs2287921 (19q13; p  =  1.61{\texttimes}10(-25), within the RASIP1 locus), rs225717 (6q24; p = 1.25{\texttimes}10(-16), adjacent to the VTA1 and NMBR loci), rs10774625 (12q24; p  =  2.15{\texttimes}10(-13), in the region of ATXN2,SH2B3 and PTPN11 loci), and rs17421627 (5q14; p = 7.32{\texttimes}10(-16), adjacent to the MEF2C locus). In two independent samples, locus 12q24 was also associated with coronary heart disease and hypertension. Our population-based genome-wide association study demonstrates four novel loci associated with retinal venular caliber, an endophenotype of the microcirculation associated with clinical cardiovascular disease. These data provide further insights into the contribution and biological mechanisms of microcirculatory changes that underlie cardiovascular disease.

}, keywords = {Adolescent, Adult, Aged, Aged, 80 and over, Cardiovascular Diseases, Child, Child, Preschool, Chromosomes, Human, Pair 12, Chromosomes, Human, Pair 19, Chromosomes, Human, Pair 5, Chromosomes, Human, Pair 6, Cohort Studies, European Continental Ancestry Group, Female, Genetic Loci, Genome-Wide Association Study, Humans, Male, Meta-Analysis as Topic, Microcirculation, Middle Aged, Polymorphism, Single Nucleotide, Retinal Vessels, Young Adult}, issn = {1553-7404}, doi = {10.1371/journal.pgen.1001184}, author = {Ikram, M Kamran and Sim, Xueling and Xueling, Sim and Jensen, Richard A and Cotch, Mary Frances and Hewitt, Alex W and Ikram, M Arfan and Wang, Jie Jin and Klein, Ronald and Klein, Barbara E K and Breteler, Monique M B and Cheung, Ning and Liew, Gerald and Mitchell, Paul and Uitterlinden, Andr{\'e} G and Rivadeneira, Fernando and Hofman, Albert and de Jong, Paulus T V M and van Duijn, Cornelia M and Kao, Linda and Cheng, Ching-Yu and Smith, Albert Vernon and Glazer, Nicole L and Lumley, Thomas and McKnight, Barbara and Psaty, Bruce M and Jonasson, Fridbert and Eiriksdottir, Gudny and Aspelund, Thor and Harris, Tamara B and Launer, Lenore J and Taylor, Kent D and Li, Xiaohui and Iyengar, Sudha K and Xi, Quansheng and Sivakumaran, Theru A and Mackey, David A and Macgregor, Stuart and Martin, Nicholas G and Young, Terri L and Bis, Josh C and Wiggins, Kerri L and Heckbert, Susan R and Hammond, Christopher J and Andrew, Toby and Fahy, Samantha and Attia, John and Holliday, Elizabeth G and Scott, Rodney J and Islam, F M Amirul and Rotter, Jerome I and McAuley, Annie K and Boerwinkle, Eric and Tai, E Shyong and Gudnason, Vilmundur and Siscovick, David S and Vingerling, Johannes R and Wong, Tien Y} } @article {6027, title = {Genetic loci for retinal arteriolar microcirculation.}, journal = {PLoS One}, volume = {8}, year = {2013}, month = {2013}, pages = {e65804}, abstract = {

Narrow arterioles in the retina have been shown to predict hypertension as well as other vascular diseases, likely through an increase in the peripheral resistance of the microcirculatory flow. In this study, we performed a genome-wide association study in 18,722 unrelated individuals of European ancestry from the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium and the Blue Mountain Eye Study, to identify genetic determinants associated with variations in retinal arteriolar caliber. Retinal vascular calibers were measured on digitized retinal photographs using a standardized protocol. One variant (rs2194025 on chromosome 5q14 near the myocyte enhancer factor 2C MEF2C gene) was associated with retinal arteriolar caliber in the meta-analysis of the discovery cohorts at genome-wide significance of P-value <5{\texttimes}10(-8). This variant was replicated in an additional 3,939 individuals of European ancestry from the Australian Twins Study and Multi-Ethnic Study of Atherosclerosis (rs2194025, P-value = 2.11{\texttimes}10(-12) in combined meta-analysis of discovery and replication cohorts). In independent studies of modest sample sizes, no significant association was found between this variant and clinical outcomes including coronary artery disease, stroke, myocardial infarction or hypertension. In conclusion, we found one novel loci which underlie genetic variation in microvasculature which may be relevant to vascular disease. The relevance of these findings to clinical outcomes remains to be determined.

}, keywords = {Aged, Aged, 80 and over, Arterioles, Chromosomes, Human, Pair 5, European Continental Ancestry Group, Female, Genetic Loci, Genome-Wide Association Study, Genotype, Humans, Male, MEF2 Transcription Factors, Microcirculation, Middle Aged, Models, Genetic, Retinal Vessels}, issn = {1932-6203}, doi = {10.1371/journal.pone.0065804}, author = {Sim, Xueling and Jensen, Richard A and Ikram, M Kamran and Cotch, Mary Frances and Li, Xiaohui and Macgregor, Stuart and Xie, Jing and Smith, Albert Vernon and Boerwinkle, Eric and Mitchell, Paul and Klein, Ronald and Klein, Barbara E K and Glazer, Nicole L and Lumley, Thomas and McKnight, Barbara and Psaty, Bruce M and de Jong, Paulus T V M and Hofman, Albert and Rivadeneira, Fernando and Uitterlinden, Andr{\'e} G and van Duijn, Cornelia M and Aspelund, Thor and Eiriksdottir, Gudny and Harris, Tamara B and Jonasson, Fridbert and Launer, Lenore J and Attia, John and Baird, Paul N and Harrap, Stephen and Holliday, Elizabeth G and Inouye, Michael and Rochtchina, Elena and Scott, Rodney J and Viswanathan, Ananth and Li, Guo and Smith, Nicholas L and Wiggins, Kerri L and Kuo, Jane Z and Taylor, Kent D and Hewitt, Alex W and Martin, Nicholas G and Montgomery, Grant W and Sun, Cong and Young, Terri L and Mackey, David A and van Zuydam, Natalie R and Doney, Alex S F and Palmer, Colin N A and Morris, Andrew D and Rotter, Jerome I and Tai, E Shyong and Gudnason, Vilmundur and Vingerling, Johannes R and Siscovick, David S and Wang, Jie Jin and Wong, Tien Y} }