Genome-wide analysis of genetic determinants of circulating factor VII-activating protease (FSAP) activity.

Essentials Knowledge of genetic regulators of plasma factor VII activating protease (FSAP) levels is limited. We performed a genome-wide analysis of variants influencing FSAP activity in Scandinavian cohorts. We replicated an association for Marburg-1 and identified an association for a HABP2 stop variant. We identified a novel locus near ADCY2 as a potential additional regulator of FSAP activity. SUMMARY: Background Factor VII-activating protease (FSAP) has roles in both coagulation and fibrinolysis. Recent data indicate its involvement in several other processes, such as vascular remodeling and inflammation. Plasma FSAP activity is highly variable among healthy individuals and, apart from the low-frequency missense variant Marburg-I (rs7080536) in the FSAP-encoding gene HABP2, determinants of this variation are unclear. Objectives To identify novel genetic variants within and outside of the HABP2 locus that influence circulating FSAP activity. Patients/Methods We performed an exploratory genome-wide association study (GWAS) on plasma FSAP activity amongst 3230 Swedish subjects. Directly genotyped rare variants were also analyzed with gene-based tests. Using GWAS, we confirmed the strong association between the Marburg-I variant and FSAP activity. HABP2 was also significant in the gene-based analysis, and remained significant after exclusion of Marburg-I carriers. This was attributable to a rare HABP2 stop variant (rs41292628). Carriers of this stop variant showed a similar reduction in FSAP activity as Marburg-I carriers, and this finding was replicated. A secondary genome-wide significant locus was identified at a 5p15 locus (rs35510613), and this finding requires future replication. This common variant is located upstream of ADCY2, which encodes a protein catalyzing the formation of cAMP. Results and Conclusions This study verified the Marburg-I variant to be a strong regulator of FSAP activity, and identified an HABP2 stop variant with a similar impact on FSAP activity. A novel locus near ADCY2 was identified as a potential additional regulator of FSAP activity.

Sex differences in coronary plaque composition evaluated by coronary computed tomography angiography in newly diagnosed Type 2 diabetes: association with low-grade inflammation.

AIM: To determine differences in coronary plaque composition and inflammatory biomarkers between men and women with newly diagnosed Type 2 diabetes without known cardiovascular disease. METHODS: A total of 88 people with newly diagnosed (<1 year) Type 2 diabetes underwent contrast-enhanced coronary computed tomography angiography. Advanced coronary plaque analysis was performed using semi-automated software. Plasma concentrations of inflammatory biomarkers were determined. RESULTS: There were no significant differences between men (n=60) and women (n=28) regarding age or cardiovascular risk factors (all P>0.05). The median (quartiles) serum levels of fibrinogen [10.9 (9.8-12.6) µmol/l vs 9.7 (8.8-10.9) µmol/l], fibrin d-dimer [0.3 (0.2-0.4) mg/l vs 0.27 (0.2-0.4) mg/l] and C-reactive protein [3.1 (1.1-5.2) mg/l vs (0.8-2.6) 1.6 mg/l] were significantly higher in women (all P<0.05). Overall, men more often had multi-vessel involvement [28 men (47%) vs 4 women (14%)], and higher total plaque burden [median (quartiles) 11.6 (2.3-36.0)% vs 2.0 (0.4-5.4)%; both P<0.05]. The median (quartiles) total plaque volume [269.9 (62.6-641.9) mm3 vs 61.1 (7.6-239.9) mm3 ] and absolute calcified plaque volume [33.5 (8.3-148.3) mm3 vs 4.7 (0.9-17.3) mm3 ] were higher in men (both P<0.05). Women had a lower relative proportion of the calcified plaque component [median (quartiles) 7.8 (4.7-15.4)% vs 23.7 (8.4-31.1)%] and a higher relative proportion (median [quartiles]) of the non-low-density non-calfied plaque component [77.6 (66.0-86.0)% vs 63.6 (54.0-72.9)%; both P<0.05]. CONCLUSIONS: In people with newly diagnosed Type 2 diabetes, women had lower absolute coronary plaque volumes but a more unfavourable plaque composition and enhanced systemic inflammation compared with men.

Somatic and social prognosis of patients with angina pectoris and normal coronary arteriography: a follow-up study.

A follow-up over a 7-year period demonstrated that 8.6% of all patients subjected to coronary arteriography because of angina pectoris had normal coronary arteries (NCA). The somatic and social prognosis of these patients were evaluated and these were compared to that of an age- and sex-matched group of patients with arteriographically verified coronary atherosclerosis (CAD). On average 44 months after coronary arteriography, 2.4% with NCA had died versus 20.5% with CAD (P < 0.001). Myocardial infarction occurred in 0% (NCA) versus 12.8% (CAD) among survivors (P < 0.001). Coronary revascularization was carried out in 0% (NCA) versus 76.9% (CAD). Chest pain was unchanged or had worsened in 58.2% (NCA) versus 21.1% (CAD) (P < 0.001) and this in the NCA patients was correlated to the occurrence of minimal lesions of the coronary arteries. Of the NCA patients, 33.3% had ischaemia during exercise-ECG. Normalization was seen in 12 patients and newly developed ischaemia in seven patients. Three patients developed ischaemia during hyperventilation test. Eighty percent (NCA) versus 63.9% (CAD) gave up work due to chest pain (P < 0.001). Further, 55.7% (NCA) versus 34.6% (CAD) had reduced daily activities (P < 0.001); similarly, the frequency of divorce was higher in the NCA group (10.2%) than in the CAD group (1.3%) (P < 0.05).