Cardiovascular disease in patients with and without hypothyroidism
C Neves, JL Medina & F Lopes
Aims: To evaluate the cardiovascular morbidity in patients with and without hypothyroidism admitted to a central hospital, between 1989 and 2004.
Materials and methods: Data from the Hospital Coding Centre were retrospectively analysed according to International Classification of Diseases (9th version) criteria. We have studied the distribution by age, sex, causes and duration of admissions. Statistical analysis was performed with Students t-test, χ2 test or Fisher exact test. Results are expressed as means ±S.D. or percentages. A two-tailed P value <0.05 was considered significant.
Results: A total of 730487 admissions were registered during the studied period. There were 211 admissions with a diagnosis of cardiovascular disease and hypothyroidism and 46042 admissions with a diagnosis of cardiovascular disease without hypothyroidism. There were no significant differences in the age of the patients with and without hypothyroidism (61.1±12.5 vs 66.7±10.5, P=NS). The duration of hospitalisation was significantly higher in hypothyroid patients (21.4±5.3 vs 14.0±2.4days, P=0.04). Patients with hypothyroidism had an incidence of cerebrovascular disease (12.8%) that was not significantly different from that in patients without hypothyroidism (12.7%). The incidence of coronary artery disease was significantly higher in patients with hypothyroidism than in patients without hypothyroidism (23.3% vs 17.5%, P=0.02).
Conclusions: Patients with hypothyroidism appear to have a higher risk of coronary artery disease. Concerning the impact of hypothyroidism in cardiovascular risk factors, the study of the interrelations of thyroids function with lipidic profile and with the immune and inflammatory tracers could contribute to the enlightenment of etiopathogenic mechanisms involved in the endothelial disfunction, enabling the definition of new therapeutic or preventive strategies.