THE PREDICTIVE VALUE OF INFLUENZA SYMPTOMATOLOGY IN ELDERLY PEOPLE

Objective. We aimed to determine the complex of symptoms which has the highest predictive value for the diagnosis of influenza. Method. A qu estionnaire study with questions regarding the symptomatology of influ enza among patients aged 60 and older (n = 1838). Thirty-four particip ating GPs recorded the symptomatology of patients who came to their ge neral practice with influenza-like complaints. The validity of the dia gnostic conclusion of the GP, as well as the diagnostic validity of th e criteria of the International Classification of Health Problems in P rimary Care (ICHPPC-2) and the Sentinel Stations in The Netherlands, w as determined with the help of the predictive value and odds ratio, us ing serologically confirmed influenza as the gold standard. The same m ethod was used to determine which complex of symptoms has the highest predictive value for influenza. The results were verified using logist ic regression analysis. Results. The predictive value of the diagnosti cs of the GP amounted to 35%. The predictive values of the diagnostics according to the criteria of the two classification methods were 24% (Sentinel Stations) and 18% (ICHPPC-2). Of the individual symptoms, th e combination of fever, coughing and acute onset had the highest predi ctive value (30.3%) for the diagnosis of influenza. Conclusion. It is recommended that the criteria of the Sentinel Stations in The Netherla nds and the ICHPPC-2 be adapted in the following way: influenza is lik ely if, out of the entire complex of symptoms, at least fever, coughin g and an acute onset occur.