Study setting and Study design
A cross-sectional study was conducted in Tigray teaching Hospitals from February to April, 2018.The data were collected using face to face interviewing questionnaire and from patients’ medical charts that was recorded from January 1, 2013 to December 30, 2018.
Study population and Sample size determination
All adult hypertensive patients who had hypertension on follow-up care at Tigray teaching hospitals, who met the inclusion criteria were included in the study. The inclusion criteria were hypertensive patients aged 18 years and above, who had regular follow-up in the cardiac clinic. Five hundred seventy eight patients met the inclusion criteria and were included in this study. A questionnaire and checklist was used to collect the data.
Eligibility criteria
Inclusion criteria
All adult hypertensive patients who had treatment follow-up of hypertension at teaching hospitals. Adults aged 18 years or older with hypertension and with e-GFR≥60 ml/min/1.73 m2 in January 2013(this is a baseline assessment) were identified and selected for this study
Exclusion criteria
Hypertensive clients who were pregnant women during the study period and client who had develop the outcome of interest before or at the beginning of follow –up start Patients with e-GFR < 60 ml/min/1.73 m2 were excluded
Sampling technique
A consecutive sampling technique was employed, and every patient was included in the study.
Data collection instrument and techniques
Data was collected using a semi-structured face to face interviewing questionnaire and patients chart review. The questionnaire had two subparts, namely socio-demographic and clinical characteristic. Te questionnaire was initially prepared in English then translated into the local language (Tigrigna) by an individual who has good ability of the two languages then translated back to English by different person to ensure consistency. A week prior to the actual data collection period, the questionnaire was pre-tested on 5% of the total sample size patients identified from Mekelle Hospital. Data was collected by four trained B.Sc. nurses and two supervisors (B.Sc. nurses)
Measurement tools
Urine Dipstick Test: Patient was asked to submit random midstream urine sample prior to admission in a 50 mL urine container for laboratory analysis for random urine dipstick test, protein, and creatinine. The dipstick analysis was done usingtheuriplus900urinalysisstip.Thefollowingarethe grades of proteinuria as provided by the manufacturers:
0: absent
Traces: 15 to 30 mg/dL
1+: 30 to 100 mg/dL
2+: 100 to 300 mg/dL
3+: 300 to 1000 mg/dL
4+: greater than 1000 mg/dL.
Estimated GFR: is a test that is used to assess how well kidneys are working. The test estimates the volume of blood that is filtered by kidneys over a given period of time. It can be measured by using readily available equations and formulas like Cockcroft – Gault. CockcroftGault formula (normalized for the body surface area [BSA]): (140 - Age [years]) x weight (kg) x (0.86, if female) x 1.73/72 x serum creatinine (mg/dl) x BSA (m2). In this case BSA will be calculated by using Mosteller formula that is BSA is equal to divided by 60, while weight is measured in kilogram and height in centimetre.
Data processing and analysis
Data was coded, entered, edited, and cleaned by Epi-data manager version 4.2 and then exported into SPSS version 23 for analysis. Chronic kidney disease was confirmed by reviewing medical chart in the hospitals. Baseline demographic, clinical, laboratory and social characteristics were used as independent variables in the analysis.
Binary logistic regression model was use to infer the association between the outcome and independent variables. In the bi-variates analysis variables with P-value <0.25 was included in the multivariable binary logistic regression. Odds ratio with 95% confidence level was computed and p-value < 0.05 was described as having a significant association.
Study variables
Dependent variable
Chronic kidney disease
Independent variable
Socio-demographic factors: Age, sex, religion, educational, occupational, income and marital status.
Clinical characteristic: Blood pressure status, baseline diastolic blood pressure, baseline systolic blood pressure and baseline, stage of hypertension, type of hypertension, number of drugs, duration on drug, types of drugs, diabetes mellitus, dyslipidemia and obese
Operational definitions
Chronic kidney disease: for this study we consider patient having CKD if the physician was diagnosed as having CKD and documented in the patient’s medical chart. Chronic Kidney disease is defined as e-GFR< 60 ml/min/1.73 m by Cockcroft Gault equations.
Controlled blood pressure : BP<140/90 mmHg using digital sphygmomanometer for adult hypertensive clients without diabetes mellitus and chronic kidney disease for at least three consecutive follow –up measurement and Blood pressure <130/80 mmHg using digital sphygmomanometer for adult hypertensive clients with diabetes mellitus and chronic kidney disease for at least three consecutive follow –up measurement
BMI (Body Mass Index): A measure of the person’s weight in kilogram divided by his height in meter square. Based on this calculation body weight classified as underweight for patient with less than 18.5Kg/m2, normal weight 18.5-24.9 Kg/m2, overweight 25-29.9 Kg/m2 and obese for patients with BMI ≥30 Kg/m2[10]
Dyslipidemia: if the patients having either of the following[10] :Total cholesterol≥200
Or Triglyceride 150 mg/dL(1.7 mmol/L) or specific treatment for this lipid abnormality or High density lipoprotein< 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
Proteinuria: according the laboratory result if a patient had plus one and above we classify as having proteinuria.
Diabetic mellitus: was defined as self-reported diabetes or the use of hypoglycaemic agents or both.
Hypertension: was defined as those who had a documented diagnosis of hypertension (i.e. BP≥140/90 mmHg) or those on anti-hypertensive agents. Target control BP was defined as BP < 140/90 mmHg for non-diabetic and < 130/80 mmHg for diabetic patients.