Valorar varios metodos para el estudio de la percepcion de la disnea en la enfermedad pulmonar obstructiva cronica (EPOC) usando un nuevo parametro, el cambio en Borg (CB), y otros ya utilizados: la pendiente de la regresion lineal y la aplicacion de la ley de Stevens a la curva respuesta-percepcion. cambios en el volumen espiratorio forzado en el primer segudno (.FEV1)-cambio en la disnea (.disnea)

Se realizo un test de broncoprovocacion a 70 pacientes con EPOC estable, sin contraindicaciones para dicha prueba (criterios de la European Respiratory Society), durante el que se midio la disnea (escala de Borg) despues de cada nebulizacion. La percepcion se analizo mediante: a) la pendiente de la regresion lineal entre. FEV1 y. disnea; b) el exponente n de la ley de Stevens (ψ=kϕn, donde ψ es. disnea y ϕ es δFEV1; cuando n < 1, la percepcion es mala, y cuando n > 1, buena), y c) el CB: diferencia entre la disnea cuando el FEV1 ha caido un 20% y la disnea tras inhalacion de salino. Se clasifico a los sujetos segun la pendiente y el CB en hipoperceptores (HPO), normoperceptores (NP) e hiperperceptores (HPR). Se compararon ambas clasificaciones mediante el estadistico kappa

Según el exponente n todos los pacientes fueron HPO (n < 1). Según la pendiente hubo 33 HPO, 28 NP y 9 HPR. El CB clasificó como HPO a 37 sujetos, como NP a 23 y como HPR a 10. La pendiente y el CB clasificaron igual a todos, excepto a 5 sujetos (kappa=0,88). En la mayoría de casos discordantes, la pendiente clasificó a los sujetos como mejor perceptores

El coeficiente n no es válido para estudiar la percepción de la disnea inducida mediante test de broncoprovocación en la EPOC. El CB es, al menos, tan útil como la pendiente para estos estudios. La proporción de HPO entre los pacientes con dicha enfermedad es elevada

To evaluate various methods for studying the perception of dyspnea in chronic obstructive pulmonary disease (COPD) using a new parameter, the change in Borg scale rating, and others already in use: the linear regression slope and the application of Stevens' law to the response– perception curve–ie change in forced expiratory volume in 1 second (.FEV1)–change in dyspnea (.dyspnea)

A bronchial challenge test was performed on 70 patients with stable COPD and no contraindications for performing the test (European Respiratory Society criteria), during which dyspnea was measured (Borg scale) after each nebulization. Perception was analyzed using: a) the linear regression slope of. FEV1 plotted against (.dyspnea); b) the exponent n of Stevens' law (ψ=kϕn, in which ψ is. dyspnea and ϕ is δFEV1, with perception being poor when n<1 and good when n > 1), and c) change in Borg: difference between dyspnea when FEV1 has fallen 20% and dyspnea after saline inhalation. Subjects were classified according to the slope and change in Borg as hypoperceivers, normal perceivers, or hyperperceivers. These 2 methods of classification were compared using the ê statistic

According to the exponent n, all patients were hypoperceivers (n<1). According to the slope, there were 33 hypoperceivers, 28 normal perceivers, and 9 hyperperceivers. The change in Borg classified 37 subjects as hypoperceivers, 23 as normal perceivers, and 10 as hyperperceivers. All except 5 subjects were classified in the same way by the slope and the change in Borg (k=0.88). In most of the 5 cases of discrepancy, the slope classified subjects as better perceivers

The n exponent is not valid for evaluating the perception of dyspnea induced by a bronchial challenge test in COPD. Change in Borg is at least as useful as the slope for evaluating perception of dyspnea. The percentage of patients with this disease who are hyperperceivers is high.