This is a cross-sectional descriptive study. Initial screening procedures included a medical history and physical examination to rule out use of medications that may affect serum lipids; oral or parenteral contraceptives;
use of drugs like Ethambutol or Pyrazinamide (that may affect uric acid levels)
At enrolment into the study, each participant was interviewed using a pro-forma (see Appendix) focusing on:
Age (recorded as at last birthday)
Age at diagnosis of diabetes or hypertension, duration of diabetes or hypertension
Family history of hypertension or diabetes
Drug history
Careful assessment of lifestyle including alcohol consumption quantification of cigarette smoked, and physical activity was also carried out.
Physical examination with emphasis on anthropometric measurements, and detailed CVD examination was carried out on each patient. The following anthropometric measurements were taken:
Weight was recorded in kilogram (to the nearest 0.1 kg) using a flat scale on a firm horizontal surface with patient wearing light clothes(184).
Height in metres was recorded with a stadiometer (positioned on a flat surface) and measured to the nearest centimeter. Subjects’ heights were measured without shoes or headgear(184).
Body Mass Index (BMI) was calculated as ratio of the measured weight to the square of the measured height (kg/m2) (30).
Waist Circumference was measured with a dress maker’s tape as the horizontal level at the mid point between the iliac crest and the lower costal margin to the nearest 0.5cm(185).
Hip Circumference was measured with a dress maker’s tape as the horizontal level at the maximum circumference over the buttock posteriorly and the pubic symphisis anteriorly to the nearest 0.5cm
(185).
Waist-to-hip Ratio (WHR) was calculated as Waist Circumference (cm) divided by hip circumference (cm) (186).
Examination of the cardiovascular system was carried out; peripheral pulses were palpated. Heart rate was recorded. Blood pressure was measured using standard sphygmomanometer (ACCOSSON variety). Blood pressure was first measured on both arms, with a five minute rest and the arm with the higher value used for subsequent measurements (two more times). The average of the last two measurements were recorded for the systolic and diastolic blood pressures. Systolic blood pressure was recorded at phase 1 Korotkoff sound and diastolic blood pressure was recorded at phase V Korotkoff sound. Blood pressure was recorded in both supine and erect positions. A cuff with a wide bladder was used for fat arms.
Fundoscopic examination was performed using a Welch Allyn ophthalmoscope. Difficult cases required the assistance of two Senior residents in ophthalmology.
MATERIALS:
Supplies
Multistix (Medi Test combi 9). Boerhinger Mannheim Germany
Micral Test Strip (ROCHE Diagnostics, Branchburg, NJ)
CLED agar media (urine culture MSU)
Capillary tubes
Plastic seal- Cristaseal
Cover Glass Reagents
Reagents for plasma glucose, serum creatinine, serum uric acid, serum cholesterol, serum triglyceride and total white cell count.
Equipments
Bench Centrifuge
Water bath (Gallen Kamp, Germany)
Spectrophotometer (PYE UNICAM P.U) 8600uv/vis Philips, Holland
Bunsen burner
Neubauer Counting Chamber
Microscope (Light)
Cardiovit AT-2 plus 6 channel ECG unit (Schiller, Switzerland)
SONOS 1500 Ultrasound System (Hewlett Packard, USA)
DCA 2000® + Analyzer ( Bayer Corporation USA)
INVESTIGATONS:
The following investigations were carried out on each patient.
Fasting plasma glucose and 2 hour post prandial glucose
Glycosylated haemoglobin (HbA1c) to assess glycaemic control for diabetics
Serum Fasting Lipids
Serum Uric Acid
Serum Creatinine
Mid-stream urine for microscopy, culture and sensitivity. This helped to treat urinary tract infection where so indicated symptomatically;
that is, in those with symptoms suggestive of a urinary tract infection before subsequent investigations for Albuminuria (clinical and micro).
Subjects who tested positive for nitrite on urine dipstick test were excluded from doing the micral test. Microalbuminuria was only looked for where clinical grade proteinuria was absent.
Urinalysis
Electrocardiography
Echocardiography
Plasma Glucose
A 12 hour fasting blood sample was collected in fluoride oxalate bottles for plasma glucose estimation. Plasma glucose was measured using the glucose oxidase method(187).
Glycosylated Haemoglobin ( HbA1C)
This was analyzed using DCA 2000® + Analyzer, which is a quantitative assay for HbA1C in the blood.The assay is based on a latex immuno-agglutination inhibition methodology.(188)All measurement and calculations were performed automatically by DCA 2000® + Analyzer and the screen displays percent of HbA1C at the end of the assay(189).
Serum Fasting Lipids
Total cholesterol, HDL-cholesterol in the serum was determined after an overnight (12 hour) fast by the enzymatic end point method(190).
Serum Triglyceride
Triglyceride in the serum was determined by the glycerol 3 phosphate oxidase (GPO) method (191,192)
Serum Creatinine
The determination of serum creatinine was by Jaffe’s method(193).
Serum Uric Acid
This was analyzed using the Phosphotungstic acid (PTA) method (194)
Packed Cell Volume (PCV)
This was determined by the mico-haematocrit method. (195)
Total White Cell Count
This was done manually using a Neubauer counting chamber. (196).
Mid Stream Urine Culture and Sensitivity
A wet preparation was use for microscopy. Culture was done using CLED agar medium(197).
Urinalysis
Multistik (Medi-test Combi 9) was used to test for clinical albuminuria and Micral test method was used to test for micro albuminuria.(198)
Electrocardiogram
The AT-2 plus, 6 channel ECG unit, Schiller (Switzerland) was operated at 15mm/s and 10mm/s.
To ensure a good quality ECG and minimize the skin-electrode resistance, it was ensured that:
The patient was warm and relaxed
The electrode area was shaven before cleaning
The area was cleaned with alcohol
The C4 electrode was placed first (5th intercostal space, mid-clavicular line). then
o C1 was placed in the 4th intercostal space, at the right sternal border
o C2 in the 4th intercostal space at the left sternal border o C3 between and equidistant to C4 and C2
o C6 on the left axillary line on the same level as C4 o C5 between and equidistant to C4 and C6(199)
It was ensured that during ECG recording, neither the patient nor the conducting parts of the patient’s connection or the neutral electrode came into contact with other persons or conducting objects even if those were earthed.
Echocardiogram
A SONOS 1500 ultrasound system (Hewlett Packard, USA) was used.
The 3.5mHz transducer was used generally and the 2.5mHz transducer for the obese patients. Echo was done with the patient lying supine at an elevation of about 30o .In the lateral position, the patient was placed in a steep left lateral decubitus position with the patient’s left arm extended over their head. This position ensured that the left lung drops away from the midline of the chest, allowed the heart to fall away from behind the dense bony sternum and maximised the intercostals spaces, thus improving
transducer accessibility. Held expiration further reduced the air-soft tissue interface and facilitated this view further.(200)
To obtain the parasternal long axis view, the transducer was placed in the third, fourth or fifth intercostals space to the left of, and close to the sternum. The transducer was placed perpendicular to the chest wall with the image index marker rotated towards the patient’s right clavicle(rotated approximately 11 o’clock).The beam was thus orientated to the long axis of the ventricle with the scan plane running parallel along an imaginary line joining the right shoulder and the left leg.(200)
LVH was diagnosed using 2D-derived, M-mode with the penn cube function(201) used alongside it. Left ventricular internal dimension in diastole (LVIDd) was taken at the peak of the R wave of the simultaneous ECG and the chordae tendinae just beyond the tip of the mitral valve leaflets.(200) Interventricular septal thickness in diastole(IVSTd) and the posterior wall thickness in diastole(PWTd) were measured by the Penn convention which excludes the thickness of endocardial interfaces in IVSTd and PWTd and has also been found to be of higher specificity than the American Society of Echocardiography specifications.(202)
4.9 CRITERIA FOR DEFINITIONS