Trends of serum thyrotropin concentration and associated factors in urban Pakistan [Karachi]

This investigation aimed at assessing trends of TSH levels and associated factors in apparently normal subjects of urban Pakistan [Karachi]. The survey was conducted in 2004 in Lyari, Karachi. Using a geographical imaging system, 85, 520 households were identified, of which 532 were randomly selected; 867 adults aged >/= 25 years consented to take part in the study. Blood samples from 324 subjects were available for analyses. Subjects with previous history of thyroid disorders were excluded. Mean age of subjects was 40.8 +/- 14.13 years; 68.2% were females; mean values of waist circumference of males and females were 89.5 +/- 16 cm 87.8 +/- 15.7 cm repectively. Fifty-nine [18.2%] subjects had TSH>6.0 cm [mU/L] based on the ELISA laboratory reference range, used for the estimation of TSH. Based on the American Thyroid Association [ATA] guidelines, 159 [49.07%] subjects had TSH<2.5, while 76 [23.45%] subjects with TSH between 2.5-4.0 mU/L as per ATA definition were in the "at risk" category. Thirty subjects [9.26%] had TSH levels between 4.1-6.0 mU/L. A significant correlation was found between TSH and BMI and waist circumference, whereas a weak, non significant one was observed between TSH and waist hip ratio. A strong association between overweight [BMI>23] and elevated serum TSH concentration [TSH>4.1 mU/L] was also observed. This spectrum of TSH levels highlighted a high prevalence of increased serum TSH levels in the population studied, a trend that was associated with obesity and various lipid abnormalities. Further population based studies are needed to correlate these findings with clinical parameters of hypothyroidism

Effect of simvastatin on insulin sensitivity in type 2 diabetic subjects

To study the effect of Simvastatin therapy on insulin sensitivity in type 2 Diabetes mellitus subjects. This is a randomized case control study, conducted at Baqai Institute of Diabetology and Endocrinology, Karachi, Pakistan. The study was conducted in 100 type 2 diabetes subjects of both sexes. Patients were randomized into two groups. Fifty patients were given Simvastatin 40mg/day for three months while 50 patients were used as controls. Both groups had similar anthropometric [age, duration of diabetes, BMI and Blood pressure] and biochemical [serum creatinine, fasting plasma glucose, fasting insulin level and lipid profile] characteristics. Insulin resistance was assessed by calculating homeostasis model assessment for insulin resistance [HOMA-IR] before and after 3 months of simvastatin treatment [40mg/day]. Simvastatin [40mg/day] markedly decreased cholesterol, triglycerides and LDL levels but did not significantly affect insulin sensitivity as determined by HOMA-IR. However it improved insulin sensitivity in subjects having insulin resistance.[HOMA IR reduction 1.92; p=0.001] Short term simvastatin therapy [3 months] had no effect on insulin sensitivity, but had a significant lipid lowering effect in all the subjects