Life Monitoring for Rural Older Adults

A 6-lead ECG will be performed using the Kardia Mobile 6L portable device (AliveCor Inc., California, USA), which is FDA approved and used in clinical practice. This device connects to an application on the phone via Bluetooth to provide instantaneous readings. To perform the measurement correctly, users are asked to sit and rest for 5 minutes. Afterwards, the user should hold the device so that the thumbs touch the upper electrodes, and the device is in direct contact with the skin of the left leg at the knee or ankle.

The device gives a diagnosis about heart beat rhythm (e.g., normal sinoauricular rhythm, arritmia, etc.)

An Omron M7 automatic blood pressure monitor (Omron Healthcare Co., Ltd., Kyoto, Japan) will be used to measure blood pressure. According to the recommendations of the American Heart Association, the user should sit in a comfortable chair with lumbar support for at least 5 minutes before the measurement. The participant will be asked to place both feet flat on the floor without crossing the legs and place the arm with the cuff at chest level on a table with the palm facing up. Make sure that the cuff is properly adjusted, but not too tight and touching bare skin, before starting the blood pressure measurement. The person being tested should not speak during this procedure to ensure an accurate and reliable measurement. An initial measurement will be taken on each arm to determine the arm with the highest blood pressure. Three measurements will be then taken at least one minute apart.

The unit measure is: Millimetre of mercury (mmHg)

A Beurer PO30 pulse oximeter (Beurer GmbH, Mittelstand, Germany) will be used and placed on the index or middle finger previously cleaned with alcohol. Participants are asked not to apply nail polish to their fingernails.

Measurement results will be given in percentage of oxygen saturation (%SatO2)

An expiratory flow meter (Datospir Peak-10, Sibelmed S.A.U, Barcelona, Spain) will be used to measure peak expiratory flow. The maneuver is performed in a seated position with both feet resting on the floor, the head in a neutral position and a nose clip is used. The participant will be instructed to perform a maximal inhalation followed by a rapid exhalation, with an expiratory effort of 1 to 2 seconds. The patient will be instructed not to cough during the technique and not to flex and/or extend the cervical spine. Three maneuvers will be performed, with the highest value being used for the analysis.

Measurement will be given in liter per minute (l/min).

The NUTRILAB BIA 101 BIVA® PRO bioimpedance device (AKERN Srl, Florence, Italy) will be used. This non-invasive method measures the body's resistance and reactance of the body to the passage of a low-intensity electric current and enables the determination of various body parameters. Bioimpedance provides accurate data on body fat percentage, muscle mass, total body water and other relevant indicators such as phase angle and Z-score. Users will be instructed to remove all metal-containing objects and remain in a supine position on a couch during the measurements, with the legs in 45° abduction, the shoulders in 30° abduction relative to the center of the body and the hands in pronation. After cleaning the skin with alcohol, two adhesive electrodes (Biatrodes Akern Srl, Florence, Italy) will be placed on the surface of the right hand and two on the right foot.

The measurement results will be given in different unit measures depending on the specific variable assessed.

• Mini-Nutritional Assessment (MNA): is a screening tool that helps to identify malnourished older people or those at risk of malnutrition. It assesses 17 items and consists of two main sections, a screening and an overall assessment. The maximum total score is 30 points, with higher scores indicating better nutritional status.
• Malnutrition Universal Screening Tool (MUST): a five-step screening tool that assesses three variables (body mass index (BMI), weight loss in 3-6 months and the impact of acute illness) to identify malnourished adults, adults at risk of malnutrition (undernutrition) or obese adults. This tool is recommended by ESPEN for adults in the community, although it is also suitable for nursing home residents and hospital patients and can be used by all health professionals. This screening serves as a predictor of hospital admissions, mortality and associated costs.

Handgrip strength will be assessed using the hand-held Jamar® Plus Smart Dynamometer (Patterson Medical Ltd., Sammons Preston, Nottinghamshire, UK). Manual grip strength will be recorded on both limbs and the dynamometer will be adjusted to hand size prior to testing. The participant's elbow should be in 90° flexion, the forearm is fully supported on a rigid surface (stretcher or table) and the shoulder is in a neutral position. Participants will be instructed to keep the flexion and extension of the wrist neutral. Three measurements will be taken with a one-minute break in between and the best one is used for the analysis.

Measurements will be given in kilograms.

is an instrument to assess the risk of frailty and the risk of falls. This test consists of three tests: a) balance tests; b) 4-meter walking speed; c) five-times stand-up and sit-down test (5STS). In the balance tests, participants will be asked to stand with their feet side by side for 10 seconds, then advance to walk in a half-tandem position for 10 seconds and finally to walk in a tandem position for 10 seconds or longer. For gait speed scoring, participants will be instructed to complete two 4-meter walks at their normal pace, with the faster of the two times being recorded for scoring. For the 5STS, participants are asked to cross their arms over their chest and stand and sit on a chair five times as fast as possible. Each item will be scored on a scale of 0 to 4 points, with a possible total possible score of 12 points, with higher scores indicating better physical performance.

The Fried frailty phenotype will be used to assess frailty status, which is composed of five main components: i) involuntary weight loss; ii) fatigue or exhaustion; iii) weakness; iv) walking speed; v) physical activity levels.

Within this tool and with the intention of assessing physical activity levels, the International Physical Activity Questionnaire (IPAQ) will be used. This questionnaire consists of 7 questions about the frequency, duration and intensity of activity (moderate and intense) performed in the last seven days, as well as walking and sitting time in a working day. This tool allows a standardized and valid measurement of physical activity and is useful in both research and public health.

Measurements will be given in a global score (0-5).

The risk of sarcopenia will be assessed using the most updated criteria of the European Working Group on Sarcopenia in the Elderly (EWGSOP 2). Following the algorithm proposed by them, the following assessments will be performed:

• SARC-F: this five-question questionnaire will be used to identify subjects at risk of sarcopenia.
• Manual grip strength: using the protocol previously described.
• Five times sit-to-stand test: this is included in the SPPB.
• Appendicular muscle mass: will be identified through bioimpedance performed through the protocol described above.
• Gait speed.

Measurements will be given in a total score and the specific results obtained in each assessment (kilograms for handgrip assessment, time (seconds) for five times sit-to-stand, total appendicular muscle mass; velocity (m/s) for gait speed; and time (seconds) for Timed Up and Go).

This will be carried out every two weeks during the seven months of the study using a semi-structured interview to record the number of cardiovascular events, hospitalizations and falls of each participant.

All measurements will be taken during the monthly evaluations scheduled for the first three months and seven months after the start of the study.