@article {1173, title = {Intravenous tissue plasminogen activator and stroke in the elderly.}, journal = {Am J Emerg Med}, volume = {28}, year = {2010}, month = {2010 Mar}, pages = {359-63}, abstract = {

OBJECTIVE: Since publication in 1995 of the National Institute of Neurological Disorders and Stroke (NINDS) trial of intravenous tissue plasminogen activator (IV tPA) for acute ischemic stroke, the benefit and frequency of use of IV tPA in the elderly have remained uncertain.

METHODS: We obtained data from the NINDS trial to summarize outcomes for randomized subjects older than 80 years. We used data from the Cardiovascular Health Study, a cohort study of 5888 elderly participants from 4 US communities followed longitudinally for stroke since 1989 to estimate the use of and hospital outcome after IV tPA in older adults following publication of the trial in 1995.

RESULTS: In the NINDS trial, 44 subjects older than 80 years were randomized, and their 3-month functional outcomes were not significantly improved with IV tPA. Of 25 randomized to IV tPA, 4 experienced symptomatic intracranial hemorrhages within 36 hours of treatment. Compared with younger patients, older patients were 2.87 times more likely to experience a symptomatic intracranial hemorrhage within 36 hours of IV tPA (95\% confidence interval, 1.04-7.93). Of 227 Cardiovascular Health Study participants hospitalized for ischemic stroke between 1995 and 2002, seven, whose mean age was 84 years, were treated with IV tPA (3.1\%; 95\% confidence interval 1.2-6.2). Two had symptomatic intracranial hemorrhages, 3 failed to improve, and 2 of the 7 had good outcomes.

CONCLUSIONS: These data highlight the need to clarify the risk-benefit profile of IV tPA in ischemic stroke victims who are older than 80 years.

}, keywords = {Aged, 80 and over, Female, Fibrinolytic Agents, Humans, Longitudinal Studies, Male, Placebos, Randomized Controlled Trials as Topic, Stroke, Tissue Plasminogen Activator, Treatment Outcome, United States}, issn = {1532-8171}, doi = {10.1016/j.ajem.2009.01.025}, author = {Longstreth, W T and Katz, Ronit and Tirschwell, David L and Cushman, Mary and Psaty, Bruce M} } @article {6367, title = {Genome-wide association study for circulating tissue plasminogen activator levels and functional follow-up implicates endothelial STXBP5 and STX2.}, journal = {Arterioscler Thromb Vasc Biol}, volume = {34}, year = {2014}, month = {2014 May}, pages = {1093-101}, abstract = {

OBJECTIVE: Tissue plasminogen activator (tPA), a serine protease, catalyzes the conversion of plasminogen to plasmin, the major enzyme responsible for endogenous fibrinolysis. In some populations, elevated plasma levels of tPA have been associated with myocardial infarction and other cardiovascular diseases. We conducted a meta-analysis of genome-wide association studies to identify novel correlates of circulating levels of tPA.

APPROACH AND RESULTS: Fourteen cohort studies with tPA measures (N=26 929) contributed to the meta-analysis. Three loci were significantly associated with circulating tPA levels (P<5.0{\texttimes}10(-8)). The first locus is on 6q24.3, with the lead single nucleotide polymorphism (SNP; rs9399599; P=2.9{\texttimes}10(-14)) within STXBP5. The second locus is on 8p11.21. The lead SNP (rs3136739; P=1.3{\texttimes}10(-9)) is intronic to POLB and <200 kb away from the tPA encoding the gene PLAT. We identified a nonsynonymous SNP (rs2020921) in modest linkage disequilibrium with rs3136739 (r(2)=0.50) within exon 5 of PLAT (P=2.0{\texttimes}10(-8)). The third locus is on 12q24.33, with the lead SNP (rs7301826; P=1.0{\texttimes}10(-9)) within intron 7 of STX2. We further found evidence for the association of lead SNPs in STXBP5 and STX2 with expression levels of the respective transcripts. In in vitro cell studies, silencing STXBP5 decreased the release of tPA from vascular endothelial cells, whereas silencing STX2 increased the tPA release. Through an in silico lookup, we found no associations of the 3 lead SNPs with coronary artery disease or stroke.

CONCLUSIONS: We identified 3 loci associated with circulating tPA levels, the PLAT region, STXBP5, and STX2. Our functional studies implicate a novel role for STXBP5 and STX2 in regulating tPA release.

}, keywords = {Aged, Cells, Cultured, Coronary Artery Disease, Endothelial Cells, Europe, Female, Gene Expression Regulation, Gene Silencing, Genetic Loci, Genetic Predisposition to Disease, Genome-Wide Association Study, Humans, Male, Middle Aged, Nerve Tissue Proteins, Phenotype, Polymorphism, Single Nucleotide, R-SNARE Proteins, Risk Factors, Stroke, Syntaxin 1, Tissue Plasminogen Activator, Transfection, United States, Up-Regulation}, issn = {1524-4636}, doi = {10.1161/ATVBAHA.113.302088}, author = {Huang, Jie and Huffman, Jennifer E and Yamakuchi, Munekazu and Yamkauchi, Munekazu and Trompet, Stella and Asselbergs, Folkert W and Sabater-Lleal, Maria and Tr{\'e}gou{\"e}t, David-Alexandre and Chen, Wei-Min and Smith, Nicholas L and Kleber, Marcus E and Shin, So-Youn and Becker, Diane M and Tang, Weihong and Dehghan, Abbas and Johnson, Andrew D and Truong, Vinh and Folkersen, Lasse and Yang, Qiong and Oudot-Mellkah, Tiphaine and Buckley, Brendan M and Moore, Jason H and Williams, Frances M K and Campbell, Harry and Silbernagel, G{\"u}nther and Vitart, Veronique and Rudan, Igor and Tofler, Geoffrey H and Navis, Gerjan J and DeStefano, Anita and Wright, Alan F and Chen, Ming-Huei and de Craen, Anton J M and Worrall, Bradford B and Rudnicka, Alicja R and Rumley, Ann and Bookman, Ebony B and Psaty, Bruce M and Chen, Fang and Keene, Keith L and Franco, Oscar H and B{\"o}hm, Bernhard O and Uitterlinden, Andr{\'e} G and Carter, Angela M and Jukema, J Wouter and Sattar, Naveed and Bis, Joshua C and Ikram, Mohammad A and Sale, Mich{\`e}le M and McKnight, Barbara and Fornage, Myriam and Ford, Ian and Taylor, Kent and Slagboom, P Eline and McArdle, Wendy L and Hsu, Fang-Chi and Franco-Cereceda, Anders and Goodall, Alison H and Yanek, Lisa R and Furie, Karen L and Cushman, Mary and Hofman, Albert and Witteman, Jacqueline C M and Folsom, Aaron R and Basu, Saonli and Matijevic, Nena and van Gilst, Wiek H and Wilson, James F and Westendorp, Rudi G J and Kathiresan, Sekar and Reilly, Muredach P and Tracy, Russell P and Polasek, Ozren and Winkelmann, Bernhard R and Grant, Peter J and Hillege, Hans L and Cambien, Francois and Stott, David J and Lowe, Gordon D and Spector, Timothy D and Meigs, James B and M{\"a}rz, Winfried and Eriksson, Per and Becker, Lewis C and Morange, Pierre-Emmanuel and Soranzo, Nicole and Williams, Scott M and Hayward, Caroline and van der Harst, Pim and Hamsten, Anders and Lowenstein, Charles J and Strachan, David P and O{\textquoteright}Donnell, Christopher J} }