RESUMO
By definition, subclinical hypothyroidism refers to biochemical evidence of thyroid hormone deficiency in patients who have few or no apparent clinical features of hypothyroidism.The subclinical hypothyroidism is diagnosed mostly by biochemical tests, in which most of the patients have a serum TSH(5-10) levels elevated above the normal reference range but serum free T3 and free T4 are normal. In subclinical hypothyroidism, most of the patients have few or no signs of thyroid dysfunction. Hence, subclinical hypothyroidism is essentially a laboratory diagnosis. MATERIAL: The study was undertaken in Rajarajeswari medical college and hospital, Bangalore. It is a case-control study, comparing 50 SCH patients, selected based on the TSH values (5-10 µIU/ml) and 50 Euthyroid(EU) patients, matched for age and gender. Data was based on history, clinical examination, thyroid function, lipid profiles and Body mass index(BMI). Student's t, chi-square tests was used for computation of p values. OBSERVATION: Dyslipidemia was significant in SCH patients compared to the control group. Further analysis of dyslipidemia showed that, total cholesterol, VLDL and LDL were all significantly elevated in cases as compared to controls with a statistical significance (p<0.001). Comparing the triglycerides, cases had higher values with statistical sig- nificance of (p=0.121). HDL was found to be reduced in cases with a statistical sig- nificance of (p=0.004). Even though 50% of cases had BMI >25 (kg/m2), it did not show any statistical significance when comparing with the TSH values. Similarly, though cases had an elevated TC,LDL,VLDL and reduced HDL, when correlating with the BMI, had no much statistical significance in both the cases and controls except for LDL which showed statistical significance of (p=0.044) in SCH cases. All the lipid variables were compared with TSH values, divided into two groups 5-8µIU/ ml and >8µIU/ml. Our study results have shown that the LDL hypercholesteremia (78.9%) was predominant followed by high Total cholesterol(42%) in SCH cases with TSH >8 (µIU/ml). Low HDL (<40 mg/dl) was seen in 57.9% of SCH cases with TSH >8(µIU/ml). CONCLUSION: SCH is common in females, in the reproductive age group and elderly women.As SCH is asymptomatic, and more of a lab diagnosis, regular screening for thyroid dis- orders forms an important part of thyroid disease management. Dyslipidemia is common in SCH patients. Further, as the dyslipidemia is seen to increase with higher TSH values,SCH needs to be treated to prevent the complications of dyslipidemia. Is considered as atherogenic condition as it increases overall cardiovascular risk. It's important to assess lipid profile and CVS risk in these patients.
