[Bronchial asthma, nasal polyposis and analgesic intolerance (the ASA triad). A successful computer based analysis of free texts].

In the period 1977 to 1980 the case histories were collected of 1731 asthmatics and 3590 non-asthmatics and stored in free text form in a computer data bank. Analyzing the data, 1643 primary asthmatics were selected comprising 537 seasonal and 417 perennial asthmatics. The incidence of nasal polyposis and chronic sinusitis on the one hand, and intolerance to analgesics on the other, was, at 9.5% and 4.5% respectively, higher in asthmatics than in non-asthmatics. In perennial asthmatics the particularly high incidences of 16% and 7.2% were observed for the two symptoms. As expected, the ASA triad (common occurrence of nasal polyposis, intolerance to analgesics and asthma) was found to be particularly frequent in perennial asthma (3.1%). A higher rate of coincidence of nasal polyposis and intolerance to analgesics was found in asthma patients than pure chance would suggest. This association is statistically significant for all asthma subpopulations. The mechanism which leads to the ASA triad is still unknown. Computer-aided analysis of free text information proved of great assistance in this study.