Page 109 - Petelin, Ana, Nejc Šarabon, Boštjan Žvanut, eds. 2017. Zdravje delovno aktivne populacije ▪︎ Health of the Working-Age Population. Proceedings. Koper: Založba Univerze na Primorskem/University of Primorska Press
P. 109
We observed that retinopathy (OR 2.32; 95%-CI: 1.05–5.13; p>0.05), ne- prevalence of silent myocardial ischemia in working-age patients 107
phropathy (OR 2.12; 95%-CI: 1.0–6.13; p>0.5), and neuropathy (OR 1.70; 95%-
CI, 1.07–2.71; p>0.05) were not associated with abnormal MPI.
Post-stress LVEF drop ≥5% was observed in 32 (91.4%) patients out of the
35 with abnormal MPI findings. In 29(82.9%) cases it was associated with post-
stress transient ischemic dilatation of LV. Patients with LVEF drop ≥5% had
higher SDS (p<0.01), but no significant difference in rest LV values (p >0.05)
compared to patients without perfusion defects.
There was no significant difference between mean rest NT-proBNP lev-
el in MPI-negative against MPI-positive subgroups (182±80ng/l vs. 198±60ng/l,
p>0.5), but patients with SMI had a significantly higher mean post-stress
NT-proBNP level (889±92ng/l vs. 226±80ng/l; p<0.05).
Univariate analysis revealed post-stress LVEF drop ≥5% (p<0.03) and
NT-proBNP level detected in early recovery stage of stress testing (p<0.05) to
be associated with greater risk of ischemia in working-age T2DM pts. In multi-
variate analysis, LVEF drop ≥5% (p<0.03) remained to be an independent pre-
dictor of SMI.
Discussion
T2DM is a chronic metabolic disease, which results not only in significant di-
rect medical costs but also in indirect productivity losses due to disability and
early mortality in working age population. Almost 75% of diabetic decedents
without clinical CAD have high-grade coronary atherosclerosis. Autopsy stud-
ies have identified a high prevalence of coronary atherosclerosis in patients
with diabetes, even among those without clinical CAD (Goraya et al., 2002).
The prevalence of SMI in the diabetic population is very variable in the differ-
ent studies, ranging from 12% to almost 57%, and it is 3 to 6 fold higher than in
asymptomatic non-diabetic population (Inoguchi et al., 2000; Wackers et al.,
2004; Freeman, 2006; Le Feuvre et al., 2011). Several mechanisms are integrat-
ed in the SMI genesis. Endothelial dysfunction secondary to T2DM may play a
role, leading to an inappropriate coronary flow response to increasing myocar-
dial metabolic needs (coronary vascular tone abnormality). It is also due to an
increased pain feeling threshold in diabetic patients, probably secondary to an
elevated beta-endorphins rate. These two abnormalities are associated with an
impaired autonomic nervous system.
The patients enrolled in the study were truly asymptomatic, working-age
subjects with T2DM, free from known CAD. There were not typical clinical
signs of angina at the time of referring patients for MPI. The patients were re-
ferred mostly from the clinics for diabetes and metabolic disorders or internal
diseases. They were on contemporary medical treatment and were under rea-
sonable metabolic control. Yet, 35 patients (18.2%) had evidence of SMI, includ-
ing 21 with moderate-to-severe reversible perfusion abnormalities and 30 with
stress-induced ST-segment changes. The prevalence of perfusion abnormalities
phropathy (OR 2.12; 95%-CI: 1.0–6.13; p>0.5), and neuropathy (OR 1.70; 95%-
CI, 1.07–2.71; p>0.05) were not associated with abnormal MPI.
Post-stress LVEF drop ≥5% was observed in 32 (91.4%) patients out of the
35 with abnormal MPI findings. In 29(82.9%) cases it was associated with post-
stress transient ischemic dilatation of LV. Patients with LVEF drop ≥5% had
higher SDS (p<0.01), but no significant difference in rest LV values (p >0.05)
compared to patients without perfusion defects.
There was no significant difference between mean rest NT-proBNP lev-
el in MPI-negative against MPI-positive subgroups (182±80ng/l vs. 198±60ng/l,
p>0.5), but patients with SMI had a significantly higher mean post-stress
NT-proBNP level (889±92ng/l vs. 226±80ng/l; p<0.05).
Univariate analysis revealed post-stress LVEF drop ≥5% (p<0.03) and
NT-proBNP level detected in early recovery stage of stress testing (p<0.05) to
be associated with greater risk of ischemia in working-age T2DM pts. In multi-
variate analysis, LVEF drop ≥5% (p<0.03) remained to be an independent pre-
dictor of SMI.
Discussion
T2DM is a chronic metabolic disease, which results not only in significant di-
rect medical costs but also in indirect productivity losses due to disability and
early mortality in working age population. Almost 75% of diabetic decedents
without clinical CAD have high-grade coronary atherosclerosis. Autopsy stud-
ies have identified a high prevalence of coronary atherosclerosis in patients
with diabetes, even among those without clinical CAD (Goraya et al., 2002).
The prevalence of SMI in the diabetic population is very variable in the differ-
ent studies, ranging from 12% to almost 57%, and it is 3 to 6 fold higher than in
asymptomatic non-diabetic population (Inoguchi et al., 2000; Wackers et al.,
2004; Freeman, 2006; Le Feuvre et al., 2011). Several mechanisms are integrat-
ed in the SMI genesis. Endothelial dysfunction secondary to T2DM may play a
role, leading to an inappropriate coronary flow response to increasing myocar-
dial metabolic needs (coronary vascular tone abnormality). It is also due to an
increased pain feeling threshold in diabetic patients, probably secondary to an
elevated beta-endorphins rate. These two abnormalities are associated with an
impaired autonomic nervous system.
The patients enrolled in the study were truly asymptomatic, working-age
subjects with T2DM, free from known CAD. There were not typical clinical
signs of angina at the time of referring patients for MPI. The patients were re-
ferred mostly from the clinics for diabetes and metabolic disorders or internal
diseases. They were on contemporary medical treatment and were under rea-
sonable metabolic control. Yet, 35 patients (18.2%) had evidence of SMI, includ-
ing 21 with moderate-to-severe reversible perfusion abnormalities and 30 with
stress-induced ST-segment changes. The prevalence of perfusion abnormalities
