BACKGROUND: High blood pressure (BP) is a major health problem in Nigeria and 
the involvement of thyroid hormones in this condition has not been evaluated in 
this center.
OBJECTIVE: The objective of this study was to evaluate the proportion of 
patients with an essential hypertension who had abnormal thyroid hormone levels 
and the type of thyroid disorders commonly observed in this group of patients.
MATERIALS AND METHODS: A retrospective study of 94 patients (30 males, aged 30.4 
± 2 years and 64 females, aged 43.4 ± 1.3 years) with essential hypertension was 
carried out between January 2005 and December 2007. Demographic and other 
medical information were obtained from the health records. Analysis of 
laboratory results of triiodothyronine (T3), Thyroxine (T4), and thyroid 
stimulating hormone (TSH) were made.
RESULTS: Of the 94 patients evaluated, 26 (27.7%) had abnormal thyroid hormone 
levels, with 23.4% having hyperthyroidism, 4.3% had sub-clinical hypothyroidism 
and none had overt hypothyroidism. Of the 26 subjects with abnormal thyroid 
hormone levels, 18 (69.2%) were females while 8 (30.8%) were males. Out of the 
18 female subjects with abnormal thyroid hormone levels, 16 had hyperthyroid 
levels while 2 had sub-clinical hypothyroid levels. Out of the 8 male patients, 
6 had hyperthyroid hormone levels while 2 had sub-clinical hypothyroid levels.
CONCLUSION: Thyroid hormone abnormalities are common in patients with essential 
hypertension. Hyperthyroidism was the most common thyroid disorder observed. 
Young patients presenting with essential hypertension should be screened for 
thyroid hormone abnormalities since they can best be managed by treating the 
underlying causes.