Study Measures
CARRS COHORT STUDY MEASURES
The CARRS Cohort core annual survey is administered by trained interviewers in face-to-face visits at the participants’ home using a tablet-based application. Questionnaires and assessments are conducted to capture repeated measures of cardiometabolic disease risk factors, health behaviors, and sociodemographic factors, as shown in the measures table below.
The CARRS Cohort is also linked to multi-level exposome assessments, including measures of air pollution, neighborhood food, and built environment. One randomly selected eligible man and one randomly selected eligible woman were sampled from each household, enabling studies of within-household factors and social influences.
In line with the strategic vision for the CARRS Cohort, data collection has been expanded to incorporate more granular exposure and outcome assessment modalities in Precision-CARRS. In addition to the questionnaire, anthropometric measurements, and biospecimen collection, P-CARRS also includes specialized imaging, ambient air pollution measurements, and integrative ‘omics analyses on stored and newly-collected bio-specimens.
| Domain | Variables | Measurement |
|---|---|---|
| Questionnaires and Wearables | ||
| Socio-demographic | Contact information, age, sex, income, education, occupation, social caste, place of birth, marital status, household size | Questionnaire |
| Health Behaviors | Dietary habits, physical activity, alcohol use, tobacco use, sleep duration and quality, COVID-19 | Modified food frequency questionnaire (FFQ), international physical activity questionnaire (IPAQ), sleep habits questionnaire, and other locally validated instruments |
| Family History | Family history of hypertension, diabetes mellitus, dyslipidemia,heart disease,stroke | Self-report |
| Physician Diagnosis of Disease | Previously diagnosed hypertension, diabetes mellitus, dyslipidemia, heart disease, stroke, chronic pulmonary disease (COPD) | Self-report / medical records |
| Medication Use | Cholesterol, glucose, lipid, and blood pressure-lowering medication | Self-report |
| Psychosocial | Depression, health-related quality of life (QoL) | Patient health questionnaire (PHQ-9) and EuroQol (EQ-5D) questionnaire |
| Environmental | ||
| Ambient Air Pollution | Daily average PM2.5 at 1kmx1km spatial resolution | B-attenuation monitors, gravimetric samplers |
| Built Environment | Vegetation index, road networks, gridwise built-up area %, intersections, light intensity, locations of pollution sources | Satellite observations and land use maps |
| Cardiometabolic Risk Factors and Outcomes | ||
| Anthropometry | Weight, height, waist and hip circumference | Tanita BC-418, Seca-213 stadiometer, tape measure |
| Blood Pressure | Systolic and diastolic blood pressure | Automated Omron HEM-7080 |
| Glucose and Insulin | Fasting, 30-min, 2-hour blood glucose; glycated hemoglobin A1c (HbA1c); fasting, 30-min, 2-hr insulin; C-peptide | Hexokinase, HPLC electrochemiluminescence immunoassay |
| Lipid Markers | Total cholesterol, high-density lipoprotein (HDL) cholesterol, and low-density lipoprotein (LDL) cholesterol; triglycerides | Direct method, Friedewald equation, Martin/Hopkins equation if triglyceride >400 mg/dl, enzymatic method |
| Renal Function | Serum and urine creatinine, albumin:creatinine ratio, cystatin C | Jaffe kinetic, spot urine, immunoturbidimetry |
| Cardiovascular Events | Heart failure, myocardial infarction, stroke, angina revascularization, peripheral artery disease | Symptoms, history, electrocardiogram (EKG), medical records | Mortality | Verbal autopsy |
PRECISION-CARRS STUDY MEASURES
Additional measures added in Precision-CARRS are shown below.
| Domain | Variables | Measurement | †Real-time health behaviors | Total steps, sleep duration | Actiwatch |
|---|---|---|
| †Ecological momentary assessment | Periodic daily stress appraisals | Smartphone application |
| Hepatic steatosis | Hepatic fat deposition | CT Scan |
| Inflammation thrombogenesis | High sensitivity C-reactive protein (hs-CRP), soluble urokinase plasminogen activator receptor (suPAR) | Abbott Labs |
| Myocardial infarction | High sensitivity troponin-I | Abbott Labs |
| Myocardial stress | B-type natriuretic peptide | Abbott Labs |
| †Genomics | Genotypes | GWAS Array |
| †Epigenomics | DNA methylation | EPIC beadchip |
| †Metabolomics | Circulating metabolites | Liquid chromatography, mass spectrometry |
| Arterial stiffness & central blood pressure | Pulse wave velocity, augmentation index | SphygmoCor, AtCor, Uscom BP+ |
| Arterial thickness | Carotid intima media thickness (CIMT) | Ultrasound | Atherosclerosis | Carotid plaque, coronory calcium (CAC) | Ultrasound, multidetector computed tomography (MDCT) | Ventricular function | Systolic/diastolic function | Echocardiogram | Advanced lipids | Apolipoproteins A1 and B; lipoprotein a (Lpa); homocysteine | Abbott labs | Adipokines | Leptin, adiponectin | Elisa assay |
† Subsamples only