We aimed to assess whether a symptom perception accuracy measure can be derived from routinely collected general population cohort data.
Methods:
We combined information on self-reported dyspnea and physiological parameters (FEV1%pred, body weight) from the Lifelines Cohort Study (N=138,594; 59.0% female; mean age=42.3 years [SD=11.0]) to obtain a symptom perception accuracy measure. Dyspnea was operationalized via the SCL-90 SOM subscale item. Using principal component analysis of available psychosocial variables known to correlate with symptom perception, we derived 3 compound scores reflecting negative affect, fear of illness, and worries of contracting disease. We used multinominal regression analyses to calculate the probability of self-reported dyspnea being correctly classified based on FEV1%pred and body weight. Via multivariable logistic regression we assessed whether the dichotomized probability of correct classification is associated with derived compound scores.
Results:
The symptom perception accuracy measure was non-normally distributed in control and participants with asthma/COPD. Fear of illness (OR=0.85; 95% CI=0.79-0.90 and OR=0.84; 95% CI=0.72-0.98) was negatively associated with the accuracy measure in control and asthma/COPD participants, respectively. Negative affect (OR=0.76; 95% CI=0.65-0.90) was associated negatively with the accuracy measure in asthma/COPD participants. Worries about contracting disease were associated with the measure in control participants (OR=0.88; 95% CI=0.83-0.94). Physiological parameters explain 1.6% to 2.5% of the variance in self-reported dyspnea; the addition of aforementioned compound scores increases this to 9.5% to 16.6%.
Conclusions:
We show that a symptom perception accuracy measure based on congruence between physiological parameters (FEV1%pred, body weight) and self-reported dyspnea can be developed. It is associated with known psychosocial correlates of symptom perception. The psychosocial factors explained more variance in self-reported dyspnea than physiological parameters.