We ask a series of questions about new illnesses, changes in lifestyle or living arrangements since the first visit to the study center, and changes in other health factors. For this purpose, we will again conduct a face-to-face interview and a computer-assisted survey (touch screen). In addition, we record the intake of medication.

With different tests we would like to examine attention, concentration and memory skills. Part of these tests is performed on a touch-sensitive screen (touchscreen).

We determine height, weight as well as various body circumferences. Body composition (percentage of muscle tissue, bone, water and fat in the total body mass) is measured using the so-called Bioelectrical Impedance Analysis (BIA). The thickness of abdominal fat (subcutaneous and visceral) is determined using an ultrasound device.

Hand grip strength is measured on both hands using a dynamometer (hand strength meter). The bicycle ergometer test is used to determine physical fitness. Before this test, it is checked whether there is an increased health risk under physical stress. Only if there are no medical reasons against it, the test is performed. To measure physical activity, a sensor (accelerometer) is placed on the participants at the study center. The small sensor worn on the body measures the acceleration forces that occur during movements over a period of seven days.

The blood glucose load test (OGTT) can be used to check whether there is an increased risk of diabetes mellitus. This test is only performed on a selection of participants. After a blood sample has been taken, the test subjects are given a sugar solution (300 milliliters) to drink. Two hours later, a second blood sample is taken. 

With the aid of a special device, the accumulation of saccharified end products in the skin tissue is determined using the so-called fluorescence technique.

Blood pressure is determined using an automatic blood pressure monitor on the arm. Heart rate is measured using a stopwatch and by feeling the pressure wave on the wrist.

When measuring functional parameters related to cardiovascular disease, a blood pressure cuff is placed on both the arm and leg and blood pressure is measured. The device takes the measurements automatically.

For the resting ECG, electrodes are placed on the upper body and on the arms and legs.  With 3-D echocardiography, the heart structures can be displayed in three dimensions while the heart is working. Again, only an ultrasound probe is moved on the skin to take pictures of the heart. To measure long-term ECG and sleep characteristics, participants will have a recording device placed on them at the study center. This automatically records the electrical activity of the heart muscle fibers over a 24-hour period. In addition, the device records sleep characteristics (e.g., sleep duration, any sleep disturbances). Breathing during sleep is also recorded with the aid of nasal cannulae.

Analysis of nitric oxide (NO) in exhaled air provides information on the presence and extent of allergic airway inflammation in respiratory diseases such as allergic asthma or allergic rhinitis. For this measurement, participants place a special filter in their mouth. They are asked to completely fill their lungs with air and then slowly and evenly exhale all of it.

After the lung function test has been explained in detail by our study staff, the subjects are asked to exhale as quickly and firmly as possible in several passes. The deep inhalation and exhalation may cause dizziness in rare cases.

When recording the tooth status, the number of teeth present is determined.

A simplified eye test is performed. In addition, a special camera is used to photograph the back of the eye to determine changes in the blood vessels at the back of the eye. The device works without contact, so there is no risk of infection.

A simple hearing test is performed on the computer with the aid of headphones. The participants are asked to pick out numbers from a background of noise.

The sense of smell is tested on 12 different odorants. This can be used to identify functional impairments of the sense of smell.

Blood is collected from a vein in the crook of the arm. The blood sample is sent to a clinical laboratory for prompt analysis. This is used to perform standard tests such as a small blood count and to determine some important metabolic parameters (e.g., cholesterol, liver enzymes).

As part of the blood collection for the basic laboratory program, additional blood samples are also obtained, which, like a urine sample, are stored long-term in two biospecimen warehouses for later analysis.

All participants of the additional MRI examination will be invited again for an MRI examination. If a subject no longer participates, he/she will be dropped without replacement. No new participants can now be added to the MRI supplementary examination.