Chronic obstructive pulmonary disease as an independent risk factor for cardiovascular morbidity.
BACKGROUND
Recent studies described association between chronic obstructive pulmonary disease (COPD) and increased risk of cardiovascular diseases (CVD). In their analysis none of these studies accounted for sociodemographic factors, health behaviors, and patient comorbidities simultaneously.


OBJECTIVE
To study whether COPD diagnosis is an independent risk factor for CVD.


METHODS
Subjects aged 40 years and older (N = 18,342) from the sample adult file of the 2002 National Health Interview Survey (NHIS) were included in the analysis. Chi-squared tests and odds ratios (OR) were utilized to compare the data. Multiple logistic regression was employed to analyze the association between COPD and CVD with simultaneous control for sociodemographic factors (age, gender, race, marital status, education, income), health behaviors (tobacco use, alcohol consumption, physical activity), and patient comorbidities (diabetes, hypertension, high cholesterol, and obesity). The analysis employed NHIS sampling weights to generate data representative of the entire US population.


RESULTS
The COPD population had increased prevalence of CVD (56.5% vs 25.6%; P < 0.0001). Adjusted logistic regression showed that COPD patients (N = 958) were at higher risk of having coronary heart disease (OR = 2.0, 95% CI: 1.5-2.5), angina (OR = 2.1, 95% CI: 1.6-2.7), myocardial infarction (OR = 2.2, 95% CI: 1.7-2.8), stroke (OR = 1.5, 95% CI: 1.1-2.1), congestive heart failure (OR = 3.9, 95% CI: 2.8-5.5), poor circulation in lower extremities (OR = 2.5, 95% CI: 2.0-3.0), and arrhythmia (OR = 2.4, 95% CI: 2.0-2.8). Overall, the presence of COPD increased the odds of having CVD by a factor of 2.7 (95% CI: 2.3-3.2).


CONCLUSIONS
These findings support the conclusion that COPD is an independent risk factor for CVD.
Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins University, Baltimore, MD 21205, USA. jfinkel9@jhmi.edu
Joseph
J
Finkelstein
Eunme
E
Cha
Steven M
SM
Scharf
D000368:Aged; D002318:Cardiovascular Diseases / Q000209:etiology* / Q000401:mortality*; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D006306:Health Surveys; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D015995:Prevalence; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications* / Q000401:mortality*; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D012907:Smoking / Q000009:adverse effects / Q000401:mortality; D014481:United States / Q000453:epidemiology