Table 1.
Harmonized variables and domains in DRPP
| Domain | Variables | Units/categories | Label |
|---|---|---|---|
| Demographic | age | years | age of participant at that visit |
| Demographic | education | no school/grade school; high school; technical/vocational/college/graduate/professional | educational categories |
| Demographic | gender | female; male | gender |
| Demographic | race_ethnicity | White; Black; Hispanic; Asian; other | race/ethnicity of participant |
| Clinical risk factors | A1C | % | hemoglobin A1C |
| Clinical risk factors | BMI | kg/m2 | body mass index |
| Clinical risk factors | casual_plasma_glucose | mg/dL | plasma glucose taken when patient has not fasted |
| Clinical risk factors | diastolic_blood_pressure | mmHg | average of diastolic blood pressure; used right arm when the choice was presented |
| Clinical risk factors | fasting_plasma_glucose | mg/dL | fasting plasma glucose |
| Clinical risk factors | HDL_cholesterol | mg/dL | high-density lipoprotein cholesterol |
| Clinical risk factors | height | cm | height (cm) |
| Clinical risk factors | LDL_cholesterol | mg/dL | low-density lipoprotein cholesterol |
| Clinical risk factors | systolic_blood_pressure | mmHg | average of systolic blood pressure; used right arm when the choice was presented |
| Clinical risk factors | total_cholesterol | mg/dL | total cholesterol |
| Clinical risk factors | use_of_anti_diabetic_medication | yes; no | use of anti-diabetic medication at current visit |
| Clinical risk factors | use_of_anti_hypertensive_medication | yes; no | use of anti-hypertensive medication at current visit |
| Clinical risk factors | use_of_lipid_lowering_medication | yes; no | use of lipid-lowering medication at current visit |
| Clinical risk factors | weight | kg | weight (kg) |
| Lifestyle | pa_met_per_week | metabolic equivalent of task (MET) (min/week) | moderate and vigorous physical activity |
| Outcomes | cesd_score | – | Center for Epidemiological Studies-Depression (CESD) |
| Outcomes | chd | yes; no | coronary heart disease (CHD); includes heart failure and/or heart attack |
| Outcomes | chd_followup | days | days to CHD event, death, or end of follow-up |
| Outcomes | cvd | yes; no | cardiovascular disease (CVD); includes CHD and/or stroke |
| Outcomes | cvd_followup | days | days to CVD event, death, or end of follow-up |
| Outcomes | death | yes; no | death indicator |
| Outcomes | death_followup | days | days to death or end of follow-up |
| Outcomes | dementia | yes; no | dementia indicator |
| Outcomes | dementia_followup | days | intermediate variables used to calculate dementia follow-up |
| Outcomes | depression_assess | yes; no | indicator of depression; based on CESD or Geriatric Depression Scale (GDS) |
| Outcomes | gds_score | – | Geriatric Depression Scale |
| Outcomes | stroke | yes; no | stroke indicator |
| Outcomes | stroke_followup | days | days to stroke event, death, or end of follow-up |
| Chronic diseases | diabetes | normal; pre-diabetes; diabetes | diabetes definition based on fasting plasma glucose, random casual glucose, A1C, and use of anti-diabetic medication |
| Chronic diseases | hypercholesterolemia | normal; elevated; hypercholesterolemia | hypercholesterolemia definition based on use of lipid-lowering medication and total cholesterol |
| Chronic diseases | hypertension | normal BP; elevated BP; hypertension stage 1; hypertension stage 2 | hypertension definition based on use of anti-hypertensive medication and blood pressure |
| Genetic | APOE | 34/44; 33; 22/23; 24 | APOE allele carrier |
| Dates | denom | yes | indicator of participant being in denominator for that visit |
| Dates | cal_time | days | days from 1960-01-01 to current visit |
| Dates | days_to_visit | days | days from initial visit to current visit |
| Cognitive tests | mmse | – | cognitive tests; mini-mental state examination |
| Behavioral | AHA_Score | 0; 1; 2 | American Heart Association diet score; 0 = poor; 1 = intermediate; 2 = ideal |
| Behavioral | alcohol | g/week | alcohol consumption in grams/week |
| Behavioral | smoking | non-smoker; former smoker; current smoker | smoking status |
The psHarmonize package was used by the research team to harmonize data from multiple cohorts. This table lists the 43 variables that were harmonized.