Objective: Assess the prevalence of subclinical hypothyroidism in the general population of an urban health
area and describe the main clinical and socio-demographic characteristics of patients with subclinical hypothyroidism.
Method: A retrospective descriptive observational study. We reviewed case histories from June 2005 to July 2007. We
analysed the following variables: General data: age and gender. Family background: thyroid pathology and other diseases.
Personal background: cardiovascular, lung, autoimmunity, gynaeco-obsetric alterations, diabetes, hypertension (HT),
dyslipidaemia, obesity, alterations of psychiatric haemotologic pathology, other laboratory data: TSH levels, free T4
levels, presence of antiperoxidase antibodies, total and partial cholesterol levels.
Results: The prevalence of our sample of 100 patients enrolled in 8 months was 3.8% with a mean of 4.2% ± 1.3 SD in the
general population aged over 14 years, of whom 79 were women and 21 were men. The; 13% were associated with type 2
diabetes mellitus, 23% with HT and 40% with dyslipidaemia. Being overweight or obese revealed a mean of 23%, TSH
level in 6.92 µU/ml, range from 4,5 to 18,75µU/ml, while the mean free T4 was 1.16 ± 0.16 ng/ml.
Conclusions: The prevalence of subclinical hypothyroidism was 3.8%. It was more frequent in women of a mean age of
46 years. Gynaecologic alternations were reported for 17% of females. The incidence of cardiovascular risk factors was
relatively high: 13% with DM, 23% with HBP, 40% with dyslipidaemia and 23% with obesity. There are no common
guidelines for subclinical hypothyroidism management. Therefore, the implementation and promotion of action guidelines
are required in Primary Health Care.