CHAPTER ONE
INTRODUCTION
1.1 BACKGROUND
Globally, the prevalence of chronic, non-communicable diseases is increasing at an alarming rate. About 18 million people die every year from cardiovascular diseases, for which diabetes is one of the major predisposing factors. Propelling the upsurge in cases of diabetes is the growing prevalence of overweight and obesity – which have during the past decade joined malnutrition and infectious diseases as major health problems threatening the developing world.
Today, more than 1.1 billion adults worldwide are overweight and 312 million of them are obese. Diabetes mellitus (DM) is the fourth highest cause of death worldwide with three million deaths annually: every ten seconds, a new death from DM is reported.
Dr Martin Silink (President, International Diabetes Federation) reported that “diabetes is one of the biggest health catastrophies the world has ever seen”.
Diabetes Mellitus is the commonest and most important endocrine disorder in Nigeria with about 4 million people estimated to be affected.
It constitutes 20% of in- patients in the medical wards at the University of Nigeria Teaching Hospital (UNTH), Enugu.
Diabetes mellitus when left uncontrolled can cause a lot of complications affecting almost all parts of the body systems. Such complications include blindness, renal failure, lower limb amputations, cerebrovascular accident, heart and blood vessel diseases, erectile dysfunction in men among others.
Diabetes mellitus itself is a major cause of cardiovascular disease and is even currently considered a cardiovascular disease equivalent. 4-6
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These complications significantly contribute to death and also impair the quality of lives of the affected individuals, care givers, families, communities involved and the nation at large. Its management can be burdensome and can distort the family balance. To the various governments especially in Africa, the problem of DM is a nightmare. The rising prevalence imposes a great burden on health systems in Nigeria. The growing prevalence of type 2 diabetes and cardiovascular disease is tied to excess weight. The burden of these diseases is particularly high in the middle-income countries of Eastern Europe, Latin America and Asia, where obesity is the fifth most common cause of the disease burden.
Consequently, diabetes is rapidly emerging as a global health care problem that threatens to reach pandemic levels by 2030; the number of people with diabetes worldwide is projected to increase from 171 million in 2000 to 366 million by 2030.
This increase will be most noticeable in developing countries, where the number of people with diabetes is expected to increase from 84million to 228 million.
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The serious cardiovascular complications of obesity and diabetes could overwhelm developing countries such as Nigeria that are already straining under the burden of communicable diseases. In Nigeria, there are no documented estimates from the available literature; however, the costs may run into several billions of naira a year, and therefore this necessitates serious attention from those who are involved in designing health programmes at the Federal, State and Local Government levels. Excess body weight can be derived from an anthropometric measurement using the weight of the individual patient in kilograms divided by the square of their height in meters square (Kg/m
). This is known as the Body Mass Index (BMI). Individuals are classified as underweight, normal weight, overweight and obese for BMI <18.5; 18.5-24.9; 25.0-29.9; and ≥30.0kg/m
respectively.
These various classes define the risk of co-morbidity.
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Obesity, which was socially and culturally acceptable among Nigerians, and therefore was not regarded as a medical problem, is now widely recognized as a rapidly growing health risk globally.
This has been attributed to the change in lifestyle with abandonment of the traditional high fiber diet and active lifestyle for diet rich in excess calories, saturated fat and sedentary lifestyle.
Obesity is an emerging problem in segments of sub-Saharan African society particularly where lifestyles are becoming urbanized and westernized. It is reported to be associated with increased risk of premature death, heart disease, hypertension and DM. 11-13
Many disorders occur with greater risk in obese people, the most important being type 2 DM, hypertension and dyslipidaemia. 11,14 Data has shown association of obesity with DM, hypertension and dyslipidaemia under the umbrella disorder called metabolic syndrome.
This shows that obesity and DM frequently co-exist and may point to common lifestyle practices associated with metabolic syndrome. Overweight and obesity predispose the individual to insulin resistance. 16-18 It has been observed that the majority of middle-aged diabetic people are obese. Obesity is known to predispose individuals to insulin resistance, possibly due to secretion of adipokines (a group of hormones) that impair glucose tolerance.
Obesity has become a global pandemic and poses multiple health risks; it is found in approximately 55% of patients diagnosed with type 2 diabetes in the United States.
In several studies, obesity has been linked with Type 2 DM in both sexes and in many ethnic groups. 20,21 It has been identified as one of the most significant modifiable risk factors for DM in Nigeria.
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Obesity, either as Body Mass Index (BMI) > 30kg/m
or Waist Hip Ratio (WHR) > 1, has been shown to independently influence the risk of glucose intolerance. 20,21,23
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The risk of cardiovascular disease is considerably greater among obese people and this group has an incidence of hypertension that is five times the incidence among people of normal weight.
The estimated risk of cardiovascular disease among persons of African origin is high and is attributed to earlier onset and later detection of diabetes and to higher blood pressure.
In Nigeria, non-communicable diseases such as DM and obesity among others have overtaken communicable diseases as the leading causes of morbidity and mortality. 24,25 The changing disease pattern has been traditionally attributed to recent advances in medicine resulting in the development of drugs and vaccines for the effective control of communicable diseases. Other factors driving this transition include changes in diet, cigarette smoking, alcohol consumption and inadequate exercise. 24,25
1.2 STATEMENT OF THE PROBLEM
Obesity is culturally and socially acceptable among Nigerians and therefore is not usually recognized as a medical problem. It is defined as an excess of adipose tissue resulting in body mass index (BMI) ≥ 30kg/m
.
Ongoing demographic and epidemiologic changes in developing countries such as Nigeria, rural to urban migration, changes in lifestyle and socio-economic factors have contributed to the burden of obesity and its co-morbidities.
In most African communities, obesity has been considered as a positive health value and never as a sign of disease. Even more, it is considered as an external sign of wealth and prosperity. To challenge such socio-cultural belief is therefore difficult when potential role models such as health workers are obese and there is paucity of data on prevalence of obesity and diabetes in Nigeria.
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There has also been a marked increase in the number of fast food centres in urban areas of the country such as Owerri which market energy dense, nutrient poor foods as well as encourage heavy consumption of glucose sweetened soft drinks and beverages. This has led to an upsurge in the number of obese patients with attendant co-morbidities such as diabetes and hypertension presenting at the General Out Patient Clinic of Federal Medical Centre Owerri. On average, obesity reduces life expectancy by 6 to 7 years
, a BMI of 30-35 reduces life expectancy by 2 to 4 years
while BMI ≥ 40 reduces life expectancy by 10years.
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Globally, rising trends in morbidity and mortality related to obesity and diabetes have led the World Health Organization and other international and national organizations to device strategies for their prevention and control. 30,31 The principal aim is to identify modifiable and non-modifiable risk factors involved in these medical conditions and to formulate a suitable programme for early detection and effective control. For instance, the Federal Ministry of Health of Nigeria (FMOH) inaugurated an Expert committee on Non-Communicable diseases (NCD) with the principal objective of identifying the risk factors involved in these conditions and formulating a suitable programme for early detection and effective control.
Also, the World Health Organization’s (WHO) Mega Countries Network for health promotion campaigns is working on solutions that involve multiple sectors. These solutions include focusing on promoting health through schools and an annual move for health initiative to increase physical activity. Researchers are also beginning to suggest that obesity itself can be used to identify without medical diagnosis those mostly at risk for several non-communicable diseases such as diabetes mellitus among others.
The burden of DM is enormous in terms of pressure on existing health resources- human and material. It is financially crippling to the individual patient in terms of diet, drugs and management
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of the complications. It is emotionally devastating for such complications as erectile dysfunction, poor vision and social stigmatization of diabetic ulcer disease and the attendant amputation. These complications can involve all the systems of the body and include diabetic foot ulcer, gangrene, renal impairment which may necessitate repeated dialysis or renal transplant, erectile dysfunction, cerebrovascular disease, retinopathy, coronary artery disease and other micro and macro vascular complications. These complications significantly contribute to death and also impair the quality of life of the affected individuals, care givers, families, communities involved and the nation at large. Its management can be burdensome and can distort the family balance. To the various governments especially in Africa, the problem of DM is a nightmare. Its rising prevalence imposes a great burden on health systems in Nigeria. Since lifestyle modifications such as increased physical activity and avoidance of energy dense foods have been shown to reduce overweight/obesity and its co-morbidities such as DM, it has therefore become pertinent to study the relationship between BMI (emphasis on overweight/obesity) and diabetes and also assess the other risk factors/co-morbidities of obesity in Owerri as this study has not been carried out in Owerri city which is regarded as the core of Ibo tribe.
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1.3 RELEVANCE OF THE STUDY TO FAMILY MEDICINE
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In Nigeria, overweight and obese patients frequently present to the General Out-Patient Clinics. The failure to diagnose these and their related morbidities such as diabetes mellitus by Family Physicians leads to missed opportunities to counsel such patients on lifestyle modifications and screen them for related morbidities. It is therefore hoped that this study would encourage regular anthropometric measurements and recording of BMI which would serve as useful prompts for the physician to discuss abnormal BMI such as overweight and obesity, encourage healthy dietary advice and lifestyle changes to help reduce and maintain weight in obese and diabetic patients. Family Physicians as first contact specialists are therefore on the front line in this particular battle to arrest and even reverse the skyrocketing obesity rates in view of this unique role they play in the health care system. The Family Physician’s office is the “place where patients’ care is coordinated and their problem list elucidated,” giving Family Physicians a huge role in educating their patients. Family Physicians understand the challenges faced by overweight and obese patients. They are among the most trusted of any health care professional, and unlike other physicians, they take care of patients from cradle to grave, positioning them to employ a long- term, patient-centered approach to obesity and weight management issues. Family Physicians must take environmental factors into consideration when treating patients who are overweight or obese and must partner with patients to make small but significant changes that will eventually result in large shifts in patient behaviour. In the last couple of years, there has been an upsurge in the number of diabetic patients presenting at Federal Medical Centre, Owerri (FMCO). Many of these patients are also found to be obese. They also share other co-morbid conditions such as hypertension and dyslipidaemia. Both DM and obesity have strong familial background and their management requires a lot of family support in form of finance and care. Coupled with the far reaching social and economic implications of their
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complications on family dynamics; in-depth knowledge and appreciation of DM and obesity and the interactions between them is very relevant in family medicine. Recent trends in the management of both diseases emphasize home care, patient`s input, family involvement/support and participation of experts in the various sub-specialties concerned with both disease conditions. The family physician, more than any other member of the medical team, fits as the leader of the team, and thus, must be at the fore of research and development of strategies for the management of these diseases. The costs of caring for people with DM and conditions that result from having poorly managed DM are very high; the pandemic would overwhelm healthcare resources everywhere if urgent actions are not taken. The goal, therefore, should be to prevent DM and its complications from being a bigger problem in Nigeria. This study would improve the knowledge and awareness of patients to the burden of obesity and diabetes and results obtained from the study would assist health policy makers (through advocacy) enact appropriate laws and regulations to help control negative lifestyle and proliferation of fast food outlets in the study area. The prevention of obesity will have a major health implication by reducing the burden of diabetes mellitus, hypertension and dyslipidaemia through lifestyle modification and improved physical activities.
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1.4 AIM AND OBJECTIVES
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Aim: To determine the relationship between type 2 diabetes mellitus and the Body Mass Index of adult diabetic patients attending the General Out-Patient Clinic of Federal Medical Centre, Owerri with a view to recommending measures for reducing weight and the burden of type 2 diabetes mellitus in the study population. Specific objectives: 1. To describe the socio-demographic characteristics of the study population. 2. To determine the prevalence of overweight and obesity in the study population using BMI. 3. To determine the relationship between type 2 diabetes mellitus and body mass index in the study population. 4. To determine relationship between hypertension, dyslipidaemia and physical inactivity as risk factors of obesity in the study population
1.5 NULL HYPOTHESIS
There is no relationship between diabetes mellitus and obesity of adult diabetic patients seen in the General Out Patient Clinic of the Federal Medical Centre Owerri.
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