C. Sri Krishna Appaji1, M. Deepak Phanindhra2, Anand Acharya3
BACKGROUND
Subclinical hypothyroidism is the term used to describe a condition where there is
isolated elevated serum thyroid stimulating hormone level in the setting of normal
serum free thyroxin levels in the absence or presence of symptoms. There is no
uniformity in various studies regarding association between subclinical
hypothyroidism and type 2 diabetes mellitus with regard to prevalence and change
in metabolic profile.
METHODS
After enrolment of patients, a detailed relevant history of patients was taken and
detailed clinical examination was done. All information obtained from patients was
recorded in predesigned proforma. After 8 hours of fasting, serum levels of
glucose, HbA1c, total cholesterol, high-density lipoprotein cholesterol (HDL-C),
triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C) by fully
automated clinical biochemistry analyser EM 200 were checked. Serum free T3,
free T4 and thyroid stimulating hormone (TSH) were measured using standard
assay.
RESULTS
Fasting glucose was significantly higher (P = .00001) in diabetes mellitus plus
subclinical hypothyroidism group than patients with diabetes mellitus (DM) and
euthyroid group (156.3 + 15.77 mg / dl vs. 128.1 + 21.44 mg / dl). Fasting insulin
was significantly higher (P = .00001) in diabetes mellitus plus subclinical
hypothyroidism group than patients with DM and euthyroid group (3.69 + 0.82
mu / L vs. 2.36 + 0.75 mu / L). There was no significant difference between two
groups regarding HbA1c.
CONCLUSIONS
From our study we conclude that prevalence of subclinical hypothyroidism was
higher in type 2 diabetes patients than normal population and there was female
predominance. Body mass index was significantly higher in subclinical
hypothyroidism group and there was no significant difference between the two
groups regarding duration of diabetes mellitus. Patients with subclinical
hypothyroidism have poor glycaemic control.
