The design of InCHIANTI assumes that the factors that influence the ability of walking can be classified into six main physiologic subsystems: central nervous system, peripheral nervous system, perceptual system, muscles, bone-joints and energy production/delivery.
The central nervous system provides the motivation for mobility and create a motor plan which is defined in the basal ganglia before been wired, through the peripheral nerves. The motor program is executed by the muscle the engine of the body and by the hard wire constituted by bone and joints. This activity requires energy production and delivery to the appropriate site plus constant feedback from a constantly changing environmental. Although this scheme is an extreme schematization of events and resources required for mobility, measures of the integrity and functioning of each of these proposed subsystems provide an exhaustive approach to the measure of mobility. These measures were administered to 1453 participants (age-range 20-102 years) selected from the populations of Greve in Chianti and Bagno a Ripoli (Tuscany, Italy), using a multistage sampling methods.
The data collection started in September 1998 and was completed in March 2000. 3 and 6-year follow-up assessment of the InCHIANTI study population were performed in the years 2001-2003 and 2004-2006. A nine-year follow-up is already planned and funded through an NIA grant.
InCHIANTI is performed in two sites: Greve in Chianti (Area 1; 11,709 inhabitants; > 65 years: 19.3%) and Bagno a Ripoli (Village of Antella, Area 2, 4704 inhabitants; > 65 years: 20.3%). To obtain two representative samples of the population, we used exactly the same two stage sampling procedure in each of the two areas.
In August 1998 a random sample of 650 persons aged 65 years or more was drawn from the population registry. Persons in this sample who were born in Italy were all considered potential participants. Then, random samples of 50 men and 50 women were drawn from the age strata 20-29, 30-39, 40-49, 50-59, 60-64 years. These persons were invited to participate in the study, until at least 30 men and 30 women for each decade in the age interval 20-59, and 10 men and 10 women in the age group 60-64 had been enrolled. The final study population included a representative sample of the older population and at least 30 men and 30 women for each 10 year age group from 20 to 100 years.
Interviews were conducted at the participants’ homes by three experienced interviewers. After receiving a detailed description of the study protocol, the participants signed an informed participation consent that included permission to consult past and future administrative databases and medical charts, and to conduct analyses on the blood cells, DNA and urine samples stored in the study biological bank. Before leaving the participant’s home, the interviewer scheduled three additional appointments and explained the proper procedure for the 24-hour urine collection, including the food to be avoided (any meat and fish) during the day of the urine collection and over the previous 48 hours.
Within three weeks by the home interview, the participant came to the study clinic for blood drawing tests, having fasted for at least 8 and just concluded the 24-hour urine collection. On the same day, the participants received a series of examinations, including: a 5-slice peripheral quantitative computed tomography (pQCT), a surface electroneurography assessing nerve conduction velocity of the right peroneal nerve, a standard electrocardiogram, an ultrasound color doppler examination of the carotid and vertebral arteries and of the veins of the lower limbs, and an assessment of the ankle-brachial index.
On the second appointment a clinical evaluation and a comprehensive motor and cognitive performences session were performed by a experied geriatrician and a trained physical therapist, respectively.