Factors associated with coronary heart disease in COPD patients and controls

Background COPD and coronary heart disease (CHD) frequently co-occur, yet
which COPD phenotypes are most prone to CHD is poorly
understood. The aim of this study was to see whether COPD
patients did have a true higher risk for CHD than subjects without COPD,
and to examine a range of potential factors associated with CHD in COPD
patients and controls Methods 347 COPD patients and 428 non-COPD controls,
were invited for coronary computed tomography angiography (CCTA) and
pulmonary CT. Arterial blood gas, bioelectrical impedance and lung
function was measured, and a detailed medical history taken. The CCTA was
evaluated for significant coronary stenosis and calcium score (CaSc), and
emphysema defined as >10% of total area <-950 Hounsfield
units.  Results 12.6% of the COPD patients and 5.7% of the
controls had coronary stenosis (p<0.01), whereas 55.9% of the COPD
patients had a CaSc>100 compared to 31.6% of the controls
(p<0.01). In a multivariable model adjusting for sex, age, body
composition, pack-years, CRP, cholesterol/blood pressure lowering
medication use and diabetes mellitus, the OR (95% CI) for having
significant stenosis was 1.80 (0.86-3.78) in COPD patients compared with
controls. In a similar model, the OR (95% CI) for having CaSc>100
was 1.68 (1.12-2.53) in COPD patients compared with controls. Examining
the risk of significant stenosis and CaSc>100 among COPD patients,
no variable was associated with significant stenosis, whereas male sex [OR
2.85 (1.56-5.21)], age [OR 3.74 (2.42-5.77)], statin use [OR 2.23
(1.23-4.50)] were associated with CaSc>100, after adjusting for
body composition, pack-years, C-reactive protein, use of angiotensin
converting enzyme (ACE) inhibitors or angiotensin receptor blockers
(ARBs), diabetes, emphysema score, GOLD category, exacerbation frequency,
eosinophilia, and hypoxemia. Conclusion COPD patients were more likely to
have CHD, but neither emphysema score, lung function, exacerbation
frequency, nor hypoxemia predicted presence of either coronary stenosis or
CaSc>100.