Sensitivity and specificity of the new Geriatric Dehydration Screening Tool: An observational diagnostic study

The aim of this study was to evaluate the diagnostic accuracy of the Geriatric Dehydration Screening Tool-Modified (GDST-M) in detecting dehydration in older people and, if possible, to simplify the tool and make it easier to use.

This was a monocentric diagnostic accuracy study. We involved people ≥65 y of age with a Mini Mental State Evaluation (MMSE) score >24 and who were hospitalized in five medical wards of a large teaching hospital in Milan (Italy). We administered the GDST-M to hospitalized older people who met the inclusion criteria and compared outcomes with the values of serum osmolarity to evaluate their dehydration status and the accuracy of the tool.

A total of 299 older people were recruited, of which 202 were dehydrated and 97 were hydrated. The GDST-M, with a cutoff value of 6, showed a sensitivity of 61.9% and a specificity of 47.2%. Multiple correspondence analysis and cluster analysis enabled extraction of 9 items from the 23 items present in the GDST-M. The new tool had a moderate diagnostic accuracy in detecting dehydration in older people aged over 75 y, with a sensitivity of 63.4% and a specificity of 69.6%.

The short form of the tool is simple and contains minimally invasive assessments of low fluid intake dehydration in older people. The new GDST could also be easily used by lay people after a short training session.