project of biostatistics

Project

Faculty of Engineering

Biomedical Engineering Department

Prevalence and risk factors of chronic kidney disease:

a population study in the Tibetan populationBy: * Mohammad Mahdi Sekhavat Pisheh – 932011113017 ([email protected]) S. Mohammad Zargar – 932011113013 Mohammad Hosein AliNaghi – 932011113022

Biostatistics

Spring 2016

Supervisor: Dr. Marateb

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First page of article

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ISI

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IF, SJR, Quartile

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#Citations

Research Question

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Is the prevalence of Chronic Kidney Disease (CKD) in the Tibetan population who have mentioned risk factors below, More than the prevalence of CKD in the population who don’t have them?

Risk factors: Hypertension, albuminuria, hyperuricemia, high hematocrit.

PICOT criteria

Population: 1289 person of the Tibetan adult(>=18 years) population in Lhasa city and Dangxiong county of Lhasa city.

Intervention: ---Comparison Group: Adults(>=18 years) who have not intended

risk factor (every time we survey).Outcome: Risk of CKDTime: --- (cross-sectional study)

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FINER criteria

Feasible

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FINER criteria

InterestingNovel

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FINER criteria

EthicalRelevant

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Research Hypothesis

: The prevalence of CKD in adults(>=18 years) who have intended risk factor (every time we survey).

: The prevalence of CKD in adults(>=18 years) who have NOT intended risk factor (every time we survey).

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Two-Sided Hypothesis:

NULL HypothesisAlternative Hypothesis

Research Objective

We conducted a population-based survey in Tibet to identify the prevalence and associated risk factors of CKD in subjects living at altitudes of >3500 m.

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Variables in the Research

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No Variable Type Measurement Scale Categories

1 Age (years) Independent Interval -

2 Weight (kg) Independent Interval -

3 Serum creatinine (μmol/L) Independent Interval -

4 Blood cholesterol (mmol/L) Independent Interval -

5 Serum triglyceride (mmol/L) Independent Interval -

6 Blood uric acid (μmol/L) Independent Interval -

7 Fast blood glucose (mmol/L) Independent Interval -

8 Systolic blood pressure (mmHg) Independent Interval -

9 Diastolic blood pressure (mmHg) Independent Interval -

10 Hemoglobin (g/L) Independent Interval -

11 Hematocrit Independent Interval -


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12 BMI Independent Interval -

13 ≥High school education Independent Nominal Above/Under

14 Health insurance coverage Independent Nominal Yes/No

15 Smoking Independent Nominal Yes/No

16 History of CKD Independent Nominal Yes/No

17 Family history of diabetes Background Nominal Yes/No

18 Family history of hypertension Background Nominal Yes/No

19 Family history of CKD Background Nominal Yes/No

20 Repeatedly respiratory tract infection Background Nominal Yes/No

21 Nephrotoxic medications Independent Nominal Yes/No

22 Obesity Independent Nominal Yes/No


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23 Central obesity Independent Nominal Yes/No

24 Metabolic syndrome Independent Nominal Yes/No

25 Hypertension Independent Nominal Yes/No

26 Diabetes Independent Nominal Yes/No

27 Hyperlipidemia Independent Nominal Yes/No

28 Hyperuricemia Independent Nominal Yes/No

29 Cardiovascular disease Independent Nominal Yes/No

30 eGFR <60 mL/min/1.73 m2 Independent Nominal Yes(<60)/No(>60)

31 ACR >30 mg/g Independent Nominal Yes(>30)/No(<30)

32 Hematuria Independent Nominal Yes/No

33 CKD Status Dependent Nominal Yes/No

Result

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The overall prevalence of CKD (stages 1–5) was 19.1% (95% CI: 17.9–22.3%) after adjustment for age and gender (Table 2). The prevalence of CKD in CKD stage from 1 to 5 was 12.8%, 4.6%, 1.1%, 0.3% and 0.3%, respectively. The prevalence of CKD was higher in the subjects with hyperuricaemia (32.3% versus 12.5%, P = 0.0001), hypertension (29.2% versus 11.9%, P = 0.0001), hyperlipidaemia (23.1% versus 10.1%, P < 0.001) and metabolic syndrome (21.8% versus 12.1%, P < 0.001) compared with subjects without these indicators, respectively. No difference of CKD prevalence was found between male and female subjects (18.9% versus 19.9%, P = 0.45), but the prevalence of CKD increased with increasing age in both groups (P < 0.001 across age groups).

Implementation of Article

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Dataset

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Normality of variables

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One-Sample Kolmogorov-Smirnov Test

What tests?

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Chi-Square test >> Between CKD and Hypertension

Mann-Whitney test >> Between CKD and Age

Bi-Variate correlation test >> Between eGFR and Age

Chi square test

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BetweenCKD and Hypertension

Chi-Square test

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Mann-Whitney test

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BetweenCKD and age

Bi-Variate correlation test

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BetweeneGFR and age

Bi-Variate correlation test

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Scatter plot

Sample size (N)calculation

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Sample size calculation

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Sample size calculation

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Thanks for your attention