Hypertension and hypothyroidism: results from an ambulatory blood pressure monitoring study

Objective To examine differences between hypothyroid patients and healthy volunteers in 24-h ambulatory blood pressure parameters. Methods The study population consisted of 100 individuals who were recently diagnosed for hypothyroidism. These patients had never been treated before with antihypertensive treatment or received drugs for hypothyroidism. All participants underwent 24-h ambulatory blood pressure monitoring. The control group consisted of 100 healthy volunteers matched one to one for gender and age with the hypothyroid participants. Results Clinic systolic and diastolic blood pressures were significantly higher in patients with hypothyroidism compared with volunteers. The mean 24-h systolic blood pressure and 24-h pulse pressure were significantly higher in patients with hypothyroidism compared with volunteers. The 24-h systolic blood pressure variability was also significantly higher in patients with hypothyroidism. Fasting serum cholesterol tended to be higher in patients with hypothyroidism compared with volunteers but the difference was not statistically significant, while fasting serum triglycerides were significantly higher. Body mass index was also significantly higher in patients with hypothyroidism. Conclusions These findings indicate that hypothyroidism may be an important predictor of higher mean 24-h systolic blood pressure, 24-h pulse pressure and 24-h systolic blood pressure variability, parameters of ambulatory blood pressure monitoring that have been previously associated with higher cardiovascular target organ damage.