ABSTRACT

Diabetes Mellitus (DM) and Thyroid Dysfunction (TD) are the two most common endocrinopathies seen in general population. Type 2 diabetes mellitus(T2DM) is commonly associated with altered thyroid function. The aim of the research is to evaluate TD in patients with T2DM attending Endocrinology Clinic of UsmanuDanfodiyo University Teaching Hospital,Sokoto.Blood samples were collected from 80 Type 2 diabetic patients and 80 non diabetic (control) and analyze for fasting blood sugar (FBS), glycatedhemoglobin (HbA1c),thyroid stimulating hormone (TSH),triiodothyrorine (T3),thyroxin (T4), cholesterol, triglycerides (TG), high density lipoprotein (HDL-C)and low density lipoproteins(LDL-C).The levels, of FBS, HbA1c,Cholesterol, TG and LDL-C were observed to be significantly high and the level of HDL-C was significantly low in diabetics as compared to control(non diabetic patients).The levels of T3 and T4 were significantly low while the level of TSH was significantly high in Type 2 diabetics as compared to non diabetics.Pearson correlation shows a very strong positive relationship between FBS and HbA1c and weak positive relationship between these sugars and Thyroid hormones(TSH,T3,andT4). Thyroid dysfunction may complicates metabolic control in diabetes mellitus (DM).It is therefore patients to recognize and where necessary treat thyroid dysfunction in order to stabilize metabolic control.

 CHAPTER ONE

1.0     INTRODUCTION

Diabetes mellitus (DM) and thyroid dysfunction (TD) are the two most common endocrine disorders seen in adult population(Diezet al., 2011).The prevalence of Type2 diabetes mellitus (T2DM) is rising faster than any other form of diabetes because of increased urbanization which encourages development of obesity due to reduced physical activities, increase consumption of refined foods and snacks globally (Zimmet, 1999; Zimmetet al., 2001).Thyroid hormones, namely Triiodothyronine (T3) and Thyroxine (T4); either or both of which may be elevated or reduced have both direct and indirect effect on blood glucose homeostasis (Udionget al.,2007).

Elevated levels of free circulating thyroid hormones (hyperthyroidism) produce hyperglycemia by causing polyphagia,enhancing glucose absorption from gastro-intestinal tract, accelerating insulin degradation and stimulating glycogenolysis (Webb,2004).Reduced level of the hormones hypothyroidism may cause hypoglycemia (Webb,2004; Cooper, 2003).

Hypothyroidism, the most commonly diagnosed thyroid dysfunction has greater implications for Type2 diabetic in whom there is pre-existing dyslipidemia and risk of cardiovascular disease (Cooper,2003;Rama et al; 2003; Johnson, 2006).Moreover, thyroid hormones have significant effects on the synthesis, mobilization and metabolism of lipid (Dias et al., 2011; Murray et al., 2000).