Handgrip strength accuracy as discriminator of functional independence in centenarian women

Abstract

The aim of this study was to verify and compare handgrip strength (HS) with activities of the daily living (ADL) and to identify the cutoff point of HGS in the prediction of independence in ADL of centenarians. Twenty-four centenarians with mean age of 101.67 ± 2.80 years participated in the study. Subjects were asked about marital status, schooling (years), diseases, hearing difficulties and activities of the daily living (Katz scale), to classify functional independence. Handgrip strength of the right hand (HSR) and left hand (HSL) (mean of the three measures of each hand) was evaluated by means of manual dynamometer. The U Mann Whitney test was applied to compare HSR and HSL with functions of ADL. To identify the cutoff point (sensitivity and specificity) of the right and left HGS of centenarians in the prediction of independence in functions of ADL, the Received Operating Characteristic (ROC) Curves were used. The following cutoff points were used: 11 Kgf for HSR (sensitivity = 66.7%, specificity = 100%, ROC curve = 0.778) and 9 Kgf for HSL (sensitivity = 66.7%, specificity = 77.8%, curve ROC = 0.730) to predict independence in performing the "bathing" function; 11 Kgf for HSR for the "continence" function (sensitivity = 83.3%, specificity = 66.7%, ROC curve = 0.712); and 9 Kgf for HSL for "transfer" function (sensitivity = 80%, specificity = 71.4%, ROC curve = 0.786). For these functions, sensitivity and specificity presented values greater than 66%. On all these functions, sensitivity showed values higher than 46% and specificity 77%. Minimum HSR is required to perform functions of ADL independently. The best HSR cutoff point to predict independence of subjects differs according to functions of activities of the daily living and hand evaluated.