Relationship between pneumonia and cardiovascular diseases: A retrospective cohort study of the general population.

AIMS: To evaluate the relationship between cardiovascular diseases (CVDs) and pneumonia in the general population.

METHODS: This retrospective observational study included two cohorts, namely CVD (n = 28,363) and non-CVD (n = 28,363) cohorts, which were matched by propensity score and examined for cases of pneumonia. Data were obtained from 2000 to 2011. In both cohorts, pneumonia risk was measured using multivariable Cox proportional hazard models.

RESULTS: With the non-CVD cohort as reference, the corresponding adjusted hazard ratios (aHRs) [95% confidence intervals (CIs)] of pneumonia were 2.03 [1.77-2.31] for coronary artery disease, 4.11 [3.15-5.36] for heart failure, 3.21 [2.70-3.81] for cerebrovascular disease, 1.46 [1.07-1.98] for peripheral vascular disease, and 2.27 [2.01-2.56] for the CVD cohort. The cohort with comorbidities had a higher risk (all p < .05) of pneumonia compared with that without comorbidities, except for patients with the comorbidities of hypertension, hyperlipidemia, obesity, and liver disease. The aHR (95% CI) of pneumonia for antibiotic use was 1.26 (1.09-1.47). The aHRs of community-acquired pneumonia (CAP) and hospital-acquired pneumonia (HAP) were 3.25 (95% CI = 1.04-10.1) and 2.95 (95% CI = 2.25-3.88), respectively. The aHRs (95% CI) were 1.78 (1.05-3.03) for intensive care unit (ICU) risk and 0.98 (0.96-0.99) for length of admission.

CONCLUSION: Pneumonia risk was associated with CVDs, especially heart failure, regardless of age, gender, comorbidities, and antibiotic use, particularly in elderly male patients. In addition, Patients with CVDs had a higher risk of CAP and HAP. The CVD cohort had a higher frequency of ICU admissions, but shorter admission lengths.