Table 1 Criteria for frailty phenotype [21]

Weight los

Differences between weight during the previous year and actual weight were calculated. Subjects with weight loss > 10 lb (4.5 kg) during this period were classified as positive for the criterion of weight loss

Self-report of exhaustion

Two questions were used from the revised version of 35 items of the Center for Epidemiologic Studies Depression Scale (CESD-R) adapted for older Mexican adults to determine the criteria of exhaustion. Items considered were: “I felt that everything I did was with difficulty” and “I could not continue.” Considered positive for the criteria was if the participant responded: “During 5–7 days in the past week” or “Almost every day for 2 weeks”

Low physical activity

Level of physical activity during the previous week was evaluated with the Physical Activity Scale for the Elderly (PASE) questionnaire that included self-reported occupational, domestic, and recreational activities. Low physical activity was considered as ≤ 58.6 points for men and ≤ 56.4 points for women (low point quartile of PASE)

Slowness

Walking time was estimated for 4.5 m (15 ft), stratified by sex and stature. Walking distance was considered in women with a height ≤ 159 cm, time ≥ 7 s and height > 159 cm, time ≥ 6 s. Walking distance was considered in men with a height ≤ 173 cm, time ≥ 7 s and with a height < 173 cm, time ≥ 6 s

Weakness (low grip strength)

Grip strength of the nondominant hand was evaluated using dynamometry (Takei T.K.K5001, Takei Scientific Instruments Co. Ltd., Tokyo, Japan) with values stratified by sex and BMI quartiles. In women, low grip strength was considered with BMI ≤ 23.0, ≤ 17 kg; BMI 23.1–26.0, ≤ 17.3 kg; BMI 26.1–29.0, ≤ 18.0 kg; BMI > 29, ≤ 21.0 kg. In men, it was considered with BMI ≤ 24.0, ≤ 29 kg; BMI 24.1–26.0, ≤ 30.0 kg; BMI 26.1–28.0, ≤ 30 kg; BMI > 28, ≤ 32.0 kg