Research Clinic Visits

Individual Visit Descriptions

Visit 1 (1972-74)
All Rancho Bernardo residents age 12 and older were invited to participate in the UCSD Lipid Research Clinic (LRC) examinations at Visit 1.  The UCSD LRC cohort included 1007 children and young adults less than age 30 who were thereafter considered members of the RBS cohort.  In addition, 5332 adults ages 30 years and older were enrolled.  The total number of participants at Visit 1 was 6339, comprising 94% of the RBS cohort.  Data collected at Visit 1 includes demographic variables such as age, place of birth, sex, marital status, occupation of head of household, education and race; physical characteristics such as weight, height, blood pressure; personal and family history of diseases such as heart disease, diabetes, cancer, stroke; medications; laboratory determination of fasting total cholesterol, triglycerides, and glucose; and information about a few health habits. Biomarkers measured: sex and adrenal hormones and SHBG were measured on a random subset of 2222 men and women, ages 30 to 79, mean age 62.3 yrs. There were 6339 participants at Visit 1; 3389 women, 2950 men; age range 5-100, mean age 52.7 yrs11% (n=727) were <20 yrs old; 16% (n=1007) were <30 yrs old.

Visit 2 (1973-75) – Lipid Sub Study
Visit 2 targeted a subset of Visit 1 participants. It occurred, on average, 3 months after Visit 1, beginning in 1973 and ending in 1975. Participants were invited to Visit 2 for one of three reasons: (1) their cholesterol or triglyceride values at Visit 1 were very high for their age and sex group (2) they were taking medications to lower cholesterol or triglycerides at Visit 1 or (3) they were part of a 15 percent random sample of all Visit 1 participants. At Visit 2, participants were interviewed extensively about their use of medications, health behaviors, reproductive and menstrual history (women only), weight history, family history of disease, and surgical history.  Participants were also asked questions to ascertain the presence of angina or possible infarction (via the standardized Rose questionnaire).  A resting ECG was performed followed by a graded exercise test (or treadmill test) for participants who showed no signs of angina or resting ECG abnormalities. More extensive lab measurements were performed including total, HDL, LDL and VLDL cholesterol. A total of 2,001 participants were examined at Visit 2; 1030 women, 971 men; age range 7-93, mean 53.4 yrs; 10% (n=200) of V2 participants were <20 yrs of age; 15% (n=292) were <30 years old

Visit 3 (1978-81) – PAD Sub Study
Visit 3, also known as the Peripheral Arterial Disease (PAD) Study, was conducted from 1978-81 and targeted a subset of RBS participants.  This was a local study, not part of a nation-wide collaborative effort as were the previous studies.  All Visit 2 participants between the ages of 40 and 80 at Visit 2 still living locally were eligible for the PAD study.  Most of the tests done at Visit 2 were repeated at the PAD visit including the Rose angina questionnaire, physical measurements such as weight and height, blood tests such as lipids, lipoproteins, and glucose.  Additional tests included glycosylated hemoglobin and several non-invasive tests aimed at measuring PAD such as blood pressure measurements in the arms, legs, ankles, and toes, and blood flow velocity. There were 624 participants in the Visit 3 PAD Study; 345 women, 279 men; age range 39-84, mean 66.4 yrs.

Visit 4 (1984-1987)
Visit 4 was the first RBS visit focused on diabetes and was conducted from 1984-87. All participants who were aged 40 and older at Visit 1 were eligible for the study; 35 participants younger than 40 years at Visit 1 were allowed to participate in Visit 4 at their request. Some residents of the RB community who had not participated in visit 1 (N=21) were newly enrolled into the RB cohort in this visit; all but 3 of these new members were aged 50 or older. Participants underwent an extensive evaluation including fasting blood chemistries, 2-hr oral glucose tolerance test, resting ECG, height, weight, blood pressure, retinal photographs to examine for diabetic retinopathy, extensive interview about personal and family medical history, reproductive and menstrual history, diet over the past year from a food frequency questionnaire, exercise, alcohol, smoking, depression, and type-A personality traits. Beginning at Visit 4 (and continuing at all subsequent visits), participants brought all current prescription and over-the-counter medications and vitamins to the clinic for detailed inventory including name, type, dose, and duration of use.

Biomarkers measured: sex and adrenal hormones, ghrelin, adiponectin, leptin and LpPLA2 were measured on men and non-estrogen using women; hsCRP, IL-6 and fasting and post-challenge glucose and insulin were measured on men and on women irrespective of estrogen use. There were 2480 participants at Visit 4; 1386 women, 1094 men; age range 23-96, mean 70.1 yrs.

Visit 5 (1988-1992)
Visit 5 was the first RBS visit to focus on cognitive function and osteoporosis. Data collected included bone scans of the wrist, forearm, spine and hip, kyphosis measurements, height, weight, blood pressure, body composition (based on bioelectric impedance), and extensive self-administered forms about personal and family medical history, reproductive history, bone fractures, current and lifetime consumption of milk and other dairy products, alcohol and soda, current medication and vitamin use, diet over the past year, lifetime exercise, and smoking. Cognitive function was evaluated for the first time using a battery of cognitive function tests. Biomarkers measured: IGF-1, IGF binding protein-1, OPG, RANKL and urinary NTX. Genetic markers measured: vitamin D receptor (VDR) and apolipoprotein E (APOE) genotypes.

Note: To enhance the target sample size for the osteoporosis measures at Visit 5, two additional groups were invited to participate.  First, 312 individuals, aged 65-80, were newly recruited into the RBS study; all had been Rancho Bernardo residents since 1978. The second group included 174 younger participants (age 30-59), who had been enrolled at Visit 1.  These groups are missing some measures from Visit 5 (e.g. they only completed the MMSE, and not other cognitive function tests).  They also have some measures not available for the main Visit 5 cohort (e.g. fasting glucose levels are available for these subgroups only).  This unique aspect should be taken into consideration when evaluating sample sizes for Visit 5 data. 

Overall, there were 2,212 participants at Visit 5; 1322 women, 890 men; age range 31-99, mean 72.0 yrs.

Visit 6 (1990-1993) – Alzheimer’s Disease Sub Study (not included in the RBS Archive)
Visit 6 was a nested case-control Alzheimer’s Disease Study conducted in collaboration with the UC San Diego Alzheimer’s Disease Research Center (ADRC). Data from this study are not included in the RBS Archive due to privacy concerns.  There were 402 participants at Visit 6.

Visit 7 (1992-1996)
Visit 7 focused on diabetes, osteoporosis, and cognitive function. Recruitment targeted all survivors who participated in Visit 4 or Visit 5, but also included 53 newly recruited age-eligible participants from the community, and 198 participants who were enrolled at Visit 1 but did not attend Visits 4 or 5.  Measurements included a 2-hr oral glucose tolerance test, ECG, retinal photograph, bone density of the spine and hip, vertebral x-ray, kyphosis measurements, body composition by whole body DXA scan and bioelectric impedance, cognitive function tests and the usual battery of questionnaires and other health measurements (height, weight, blood pressure, blood lipids, etc). Hearing acuity was assessed. Biomarkers measured: IGF-1 (clinical laboratory). There were 1,781 participants at Visit 7; 1082 women, 699 men; age range 31-98, mean 71.5 yrs.  

Visit 8 (1997-1999)
All RBS members who participated in Visit 5 or 7 were invited back to the clinic in Rancho Bernardo to repeat many measurements taken at the earlier visits including fasting glucose, ECG, bone density of the spine and hip, kyphosis measurements, body composition, and other health measurements (height, weight, blood pressure, blood lipids, etc).  The oral glucose tolerance test and retinal photographs were NOT repeated.  New tests included measures of cardiovascular health: carotid ultrasound, cardiac output (ejection fraction) and vascular compliance.  Biomarkers measured: 25-hydroxyvitamin D, 1,25-dihydroxy-vitamin D, PTH, OPG, RANKL, endothelin-1. There were 1096 participants at Visit 8; 676 women, 420 men; age range 38-97, mean 74.3 yrs.

Visit 9 (1999-2002)
Visit 9 was a follow-up study to prior bone and cognitive health visits to prospectively study sex-specific causes and consequences of bone loss, fracture and cognitive decline. Participants must have had a bone scan from a previous visit and a vertebral x-ray from Visit 7.  Repeat measurements of bone mineral density and vertebral fractures, the battery of cognitive function tests, and many other clinical, behavioral and functional related data were obtained. Biomarkers measured: total and bioavailable sex hormones on a subset of 313 men, age 65 years and older who completed the ADAM (Androgen Deficiency in the Aging Male) questionnaire in Mailer 20. There were 1141 participants at Visit 9; 678 women, 463 men; age range 43-99, mean 74.2 yrs.

Visit 10 (2003-2006)
Participants targeted for participation in Visit 10 were age 65 and older and had a bone scan from a previous study and a vertebral x-ray from either Visit 8 or 9.  Repeat measurements of spine and hip BMD and spine radiographs were obtained, and other medical and functional status measurements were reassessed. A new DXA method to diagnose vertebral fractures (VFA – vertebral fracture assessment) was measured for the first time.  The battery of cognitive function tests was repeated. Biomarkers measured: bone markers – serum and urine NTX, serum P1NP. There were 870 participants at Visit 10; 526 women, 344 men; age range 43-100, mean 74.0 yrs.

Visit 11 (2007-2009)
Surviving RBS participants who had at least 3 prior DXA scans were invited back to obtain repeat measurements of cognitive function and bone mineral density, as well as many other clinical, behavioral and functional data, including predictors of bone loss, kyphosis, bone size and strength, fracture, functional limitations and comorbidity.  There were 733 participants at Visit 11; 420 women, 313 men; age range 48-105, mean 76.0 yrs.

Visit 12 (2013-2016)
Visit 12 was designed to collect structural brain measures from a subset of surviving participants who had undergone a prior cognitive function assessment. Participants completed a more extensive cognitive battery and provided detailed information on health behaviors and medical history. Participants had blood pressure, height, weight, and waist and hip circumference measured; completed the Rose angina questionnaire; and contributed spot urine and fasting blood samples.  Medications/supplements were reviewed and recorded. There were 221 participants at Visit 12; 123 women, 98 men; age range 56-99, mean 77.5 yrs.168 completed the structural MRI.

RBS Sub Studies for measurement of coronary artery calcification

Coronary artery calcification (CAC) was measured by electron beam computed tomography (EBCT) scans on a select subset of RBS participants at a San Diego EBCT clinic in 2000-2002 and repeated approximately 4.5 years later in 2005-2007.

  • CAC 1 Sub Study (2000-2002)

Clinic visits for the first CAC scan began in 2000 and ran through 2002.  Participants without known cardiovascular disease (CVD) including coronary revascularization (based on Visit 7 data, or by self-report during a telephone screen in 2000-2002) were eligible.  Measurements of CAC were obtained in the left descending, left circumflex, left main, and right coronary arteries.  Abdominal visceral and subcutaneous adipose tissue masses were also measured and statin use was queried.  Biomarkers for CAC 1 were measured on stored samples collected at Visit 7. Biomarkers measured: leptin, adiponectin, hsCRP, IL-6, TNFα, OPG and RANKL. There were 200 men and 222 women at CAC 1; age range 46-88, mean 67.2 yrs.

  • CAC 2 Sub Study (2005-2007)

Clinic visits for CAC 2 began in 2005 and continued through 2007.  Eligibility was limited to individuals who participated in CAC 1 (2000-2002) and who remained free of CVD events. Repeat measurements of CAC were obtained in the left descending, left circumflex, left main, and right coronary arteries. Abdominal visceral and subcutaneous adipose tissue masses were also measured and statin use was queried. Overall, 148 men and 177 women returned for CAC 2; age range 51-92, mean 66.3 yrs.