Complications and Associated Conditions among Omani Type 2 Diabetes Patients at Sultan Qaboos University Hospital, Muscat, Oman

Research Article

J Fam Med. 2014;1(3): 6.

Complications and Associated Conditions among Omani Type 2 Diabetes Patients at Sultan Qaboos University Hospital, Muscat, Oman

Al-Sinani S*, Al-Mamari A, Woodhouse N, Al- Shafie O, Amar F, Al-Shafaee M, Hassan M, Bayoumi R

Department of Biochemistry, College of Medicine and Health Sciences, Sultan Qaboos University, Oman

*Corresponding author: Sawsan Al Sinani, Department of Biochemistry, College of Medicine & Health Sciences, Sultan Qaboos University, Sultanate of Oman

Received: October 17, 2014; Accepted: November 25, 2014; Published: November 29, 2014

Abstract

Objective: To estimate the prevalence of type 2 diabetes (T2D) complications and associated conditions among Omani patients at Sultan Qaboos University Hospital (SQUH).

Methods: A total of 986 T2D Omani patients was included in this study. Data were collected from June 2010 to February 2012. Data include demographic, anthropometric and biochemical investigations. Complications among patients were recorded.

Results: Thirty-six percent of the patients were overweight and 51% were obese. Thirty-five percent of the patients had high serum total cholesterol, 63% had high LDL cholesterol, 38% had high serum triglycerides, while 50% and 48% of the males and females, respectively, had low HDL cholesterol. Half of the patients had at least one T2D complication, while 86% had a complication or associated condition. Twenty percent had coronary artery disease, 5% had a stroke, 66% had hypertension, 10% had documented retinopathy, 15% had microalbuminuria, 31% had nephropathy, 9% had neuropathy and 2% had peripheral vascular disease.

Conclusion: The prevalence of diabetes complications and associated conditions among Omani T2D patients was not different from other populations. However, prevalence of retinopathy and neuropathy was lower and this indicates the need for a proper assessment and documentation.

Keywords: Type 2 Diabetes; Omani; Complications; Associated conditions; Prevalence

Abbreviations

T2D: Type 2 Diabetes; SQUH: Sultan Qaboos University Hospital; BP: Blood Pressure; CVD: CardioVascular Dseases; PVD: Peripheral Vascular Disease; IGT: Impaired Glucose Tolerance; MI: Myocardial Infarction; ESRD: End Stage Renal Disease; BMI: Body Mass Iindex; ACR: Urine MicroAlbumin/Creatinine Ratio; ADA: American Diabetes Association; EGFR: Estimated Glomerular Filtration Rate; CKD: Chronic Kidney Disease; CAD: Coronary Artery Disease; HDL: High Density Lipoprotein cholesterol; LDL: Low Density Lipoprotein cholesterol; NSTEMI: Non-ST segment Elevation Myocardial Infarction; STEMI: ST segment Elevation Myocardial Infarction.

Introduction

Type 2 diabetes mellitus (T2D) is associated with acute and chronic metabolic consequences, where the frequency of events varies according to the level of glycemic control, blood pressure (BP) and dyslipidemia. Acute fluctuations in serum glucose may lead to emergency situations (e.g. Diabetic ketoacidosis, hyperosmolar hyperglycemic syndrome or severe hypoglycemia). Longer-term follow up is required to promote better blood glucose regulation and avoidance of diabetic emergencies. Glucose dysregulation is also associated with damaging effects on tissues, leading to complications. Diabetes increases the risk of microvascular and macrovascular diseases. Microvascular diseases include retinopathy, nephropathy, neuropathies, and the consequences that stem from these (e.g. congestive heart failure, diabetic foot). Macrovascular diseases include cardiovascular diseases (CVD), cerebrovascular disease or “stroke” and peripheral vascular disease (PVD). These complications are associated with considerable morbidity, reduced quality of life, disability, premature mortality and high economic costs.

Diabetes and impaired glucose tolerance (IGT) increase CVD risk three-to eightfold. Thus, over 40% of patients hospitalized with acute myocardial infarction (MI) have diabetes and 35% have IGT. In addition, new blood vessel growth in response to ischemia is impaired in diabetes, resulting in the decreased collateral vessel formation in ischemic hearts, and in non-healing foot ulcers. DM is also now the leading cause of new blindness in people 20 – 74 years of age and the leading cause of end stage renal disease (ESRD) in the developed world. Survival of patients with diabetic ESRD on dialysis is half that of those without diabetes. More than 60% of patients with diabetes are affected by neuropathy, which includes distal symmetrical polyneuropathy, mononeuropathies and a variety of autonomic neuropathies causing erectile dysfunction, urinary incontinence, gastroparesis and nocturnal diarrhea. Diabetes accelerated lower extremity arterial disease in conjunction with neuropathy accounts for 50% of all non-traumatic amputations in the USA [1].

Hypertension is also one of the most significant secondary risk factors for the development of microvascular diabetic complications. In both retina and glomerulus, reduction of the vascular surface area appears to occur first in microvessels with high perfusion pressure. Tight control of blood pressure delays the progression of retinopathy and nephropathy, while elevated blood pressure accelerates the onset of nephropathy and its progression [2]. The term diabetic dyslipidemia refers to the lipid abnormalities typically seen in persons with T2D. It is characterized by elevated serum triglyceride and LDL cholesterol concentrations and low serum HDL cholesterol concentrations.

T2D is also associated with the “metabolic syndrome,” a collection of cardiovascular risk factors (abdominal obesity, hyperinsulinemia, hypertension, dyslipidemia, proinflammatory and procoagulant states). These factors increase the likelihood of developing additional risks, and with each added risk, predispose one to an increasing risk of atherosclerotic vascular disease events and mortality [3].

If diabetes is treated properly, the mortality from acute and chronic hyperglycemia is reduced. Patients and resources (e.g. Hospital facilities, experience of staff, etc.) characteristics may also modify the outcomes. Inadequate therapeutic instruments and medication, and insufficient numbers of trained staff result in poor glycemic control and higher risk of mortality.

This is a retrospective study aimed at estimation of the prevalence of microvascular and macrovascular complications of T2D as well as the prevalence of diabetes associated conditions among Omani patients. Information provided by this study will allow the clinicians to draw appropriate plans for reduction and prevention of diabetes complications among the Omani population.

Materials and Methods

Sample size calculation

Sampsize website was used for calculating the sample size. Using precision of 2%, a prevalence of 11%, population size of 2 million and 95% confidence interval, a minimum of 940 patients should be used in this study.

Sample collection

A total of 986 T2D Omani patients was included in this study. T2D patients were recruited from the Diabetes Clinic (n= 523), Family Medicine Clinic (n= 150) and as inpatients (n= 313) at Sultan Qaboos University Hospital (SQUH), a countrywide tertiary referral center in Oman. A history of T2D among patients was ascertained from the diagnosis and medical history deposited in the electronic records of the hospital information system. The inclusion criteria were Omani T2D patients, over 18 years old. Exclusion criteria included: patients diagnosed with type 1 diabetes; positive antibodies (islet cell antibodies and glutamic acid decarboxylase antibodies) or patients diagnosed with any type of cancer. Data were collected from June 2010 to February 2012. Participants were informed about the project and written consent was obtained. The study was approved by the Ethics and Research Committee of the College of Medicine, Sultan Qaboos University, Muscat, Oman.

Anthropometric and Biochemical data

Data on demographic, anthropometric and biochemical investigations were collected from the hospital information system, electronic records, and summarized in Table 1. Patient’s weight and height were collected and body mass index (BMI) was calculated [weight (kg) /height2 m(2)]. Obesity status was defined according to the international classification of an adult’s weight, [Normal BMI: 18.5 - 24.99 kg/m2, overweight: 25.00 - 29.99 kg/m2 and obese ≥ 30.00 kg/m2]. Blood pressure and duration of diabetes among patients were documented. The biochemical investigations included: serum fasting glucose, HbA1C level, serum creatinine, serum total cholesterol, LDL-cholesterol, serum HDL-cholesterol, serum triglycerides and urine microalbumin/creatinine ratio (ACR). American Diabetes Association (ADA) criteria for diabetes lipid control were used to define hyperlipidemia, and summarized in Table 2 [4]. Estimated glomerular filtration rate (eGFR) was calculated from serum creatinine. ACR and eGFR were used to assess kidney function among patients (Normal kidney function: normal urine ACR (men ≤ 2.5 mg/mmol, women ≤ 3.5 mg/mmol) and normal eGFR (≥90 ml/ min/1.73m2); Microalbuminuria: Urine ACR: 2.6-29 mg/mmol (men) and 3.6 - 29 mg/mmol (women); chronic kidney disease (CKD) stage 2: eGFR= 60 - 89 ml/min/1.73m2; CKD stage 3: eGFR= 30 - 59 ml/ min/1.73m2; CKD stage 4: eGFR= 15 - 29 ml/min/1.73m2 and CKD stage 5: eGFR < 15 ml/min/1.73m2 or on dialysis [5].