Study setting and period
A hospital based cross section study design was conducted in Ayder comprehensive specialized hospital (ACSH) from February to June 2018. ACSH is found in Mekelle the capital city of Tigray region northern of Ethiopia. Mekelle is located around 780 kilometers north of the Ethiopian capital city Addis Ababa. The study participants were previously diagnosed/known type 2 DM patients. DM clinic is served for about 500 type 2 DM patients per month that is estimated from the average of the last six months report.
Study design: A hospital based cross section study design.
Source patients: All type 2 diabetes patients attending DM clinic at ACSH.
Study patients: All volunteer type 2 DM patients attending DM clinic and available at ACSH during the data collection period.
Study subjects: All sampled subjects (419) participated in this study
Inclusion criteria
- All type 2 diabetes mellitus patients
Exclusion criteria
- Critically ill patient
- Pregnant mother (difficult to measure BMI and waist circumference)
Sample size determination
The sample size was calculated by using single proportion formula, n= [Za/2]2 p(1-p)/d2 at 95% confidence level, where,
Za/2 = standard normal deviation (1.96), d = 5% of marginal error, and p= prevalence 45.9% taken from a study conducted in Ethiopia(10).
n = (1.96)2 x 0.459(0.541)/(0.05)2 , n= 382
Considering 10% non-response rate, because of some respondents may withdraw in between the interview, the total estimated study subjects were 419 and selected by systematic random sampling technique with kth interval of 2 and every second (2) was participated by random selection from 1- 2(kth).
Data collection procedure
Data collection was carried out from February to March 2018. To collect data a standardized, interviewer administered questionnaire and document review checklist of physical measurements, residence (urban or rural) for the last six month, co-morbid disease like hypertension, CHF, stroke were used and contains three parts. Thus are socio-demographic and medical history, the life style and related information.
Measurements and tools
Anthropometric measurements: Anthropometric measurements of weight and height was measured using Seca weighing scale and stadiometer respectively and participants were wearing light clothing (single and thin) and without shoes to the nearest Kg and CM respectively. A simple flexible steel metric tape calibrated in meters was used for measuring waist circumference. Waist circumference was measured midway between the iliac crest and the lower rib margin in the horizontal plane while the participant is standing to the nearest 0.5 centimeter.
Blood pressure: Two blood pressure measurements taken after five minutes apart were determined for each participant using standard adult digital blood pressure apparatus with the correct size arm cuff. Participants was measured after 5 minutes of rest in sitting position, arm should be rest on table at heart level, back supported, on the same arm and legs rest on ground (no crossed). And the average readings of the two measurements was recorded in questionnaire (11).
Data quality assurance
Questionnaire was prepared in English and translated in to local language Tigrigna by expert in language. Pretest was done on 5% of the subjects in Mekelle hospital two weeks before the actual data collection. Because Mekelle hospital is near to ACSH and have similar socio-demographic characteristics with patients in ACSH. Two BSC nurses and one supervisor were recruited for data collection and training was given. The collected data was checked by supervisor and principal investigator daily.
Data processing and analysis
After the data collection, the data was entered in to Epi-info version 7 and exported to SPSS version 23 statistical program. Descriptive characteristics were presented in text, frequency percentage tables, and graphs. Binary logistic regression model was used to see the association between the outcome variable with each independent variables. Then those variables with P-value <0.25 at bivariate analysis was included in the multivariable analysis. Finally P-value < 0.05 is describe as a statistically associated with 95% confidence level. Model fitness was checked by using Hosmer and Lemeshow goodness fit model.
Operational definition
Metabolic syndrome: As per the definition of international diabetes federation it is defined as having central obesity (defined by waist circumference ≥ 94 cm for male and ≥ 80 cm for female) plus any two of the following four factors: raised triglycerides, reduced HDL Cholesterol, raised blood Pressure, and/or raised fasting plasma glucose.
Central obesity: defined by waist circumference ≥ 94 cm for male and ≥ 80 cm for female putting to the nearest centimeter.
Raised triglycerides: ≥ 150 mg/dL (1.7 mmol/L) or specific treatment for this lipid abnormality.
Reduced HDL Cholesterol: < 40 mg/dL (1.03 mmol/L) in male < 50 mg/dL (1.29 mmol/L) in female or specific treatment for this lipid abnormality.
Raised blood Pressure: Is a systolic BP ≥ 130 mm Hg or diastolic BP ≥ 85 mm Hg, or any patient on treatment of previously diagnosed hypertension..
Reduce salt intake: about1 tea spoon of table salt per meal