Relations among questionnaire and laboratory measures of rhinovirus infection

¹ University of Wisconsin, Madison, Madison, Wisconsin, USA
² University of Virginia, Charlottesville, Virginia, USA

^* To whom correspondence should be addressed. E-mail: bruce.barrett{at}fammed.wisc.edu.

	Abstract

Due to high incidence and quality-of-life impact, upper respiratory infection substantially impacts population health. To test or compare treatment effectiveness, a well-designed and validated illness-specific quality-of-life instrument is needed.

Data reported here come from a trial testing echinacea for induced rhinovirus infection. Laboratory-assessed biomarkers include interleukin-8 (IL-8), nasal neutrophil count (PMN), mucus weight, viral titer and seroconversion. Questionnaires include the general health SF-8 (24 hour recall version), the 8-item Jackson cold scale, and the 44-item Wisconsin Upper Respiratory Symptom Survey (WURSS-44).

399 participants were inoculated with rhinovirus and monitored over 2,088 person-days. Statistically significant associations were found among nearly all variables. Between questionnaire correlations were: WURSS-Jackson=0.81; WURSS-SF8=0.62; Jackson-SF8=0.60. Correlations with laboratory values: WURSS-mucus-weight=0.53; Jackson-mucus-weight=0.55; WURSS-viral titer=0.37; Jackson-viral titer=0.46; WURSS-IL-8=0.31; Jackson-IL-8=0.36; WURSS-PMN=0.31; Jackson-PMN=0.28. Neither WURSS nor Jackson yielded satisfactory cutoff scores for diagnosis of infection.

Symptomatic and biological outcomes of URI are highly variable, with only modest associations. While WURSS and Jackson both correlate with biomarkers, neither is a good predictor of induced infection. Inclusion of functional and quality-of-life items in WURSS does not significantly decrease the strength of association with laboratory-assessed biomarkers.