RESPIRATORY ILLNESS AND MORTALITY IN ENGLAND AND WALES - A STUDY OF THE RELATIONSHIPS BETWEEN WEEKLY DATA FOR THE INCIDENCE OF RESPIRATORY-DISEASE PRESENTING TO GENERAL-PRACTITIONERS, AND REGISTERED DEATHS

The possible relationship between the incidence of respiratory disease s as reported to general practitioners and numbers of registered death s in England and Wales has been examined. Morbidity data from sentinel practices for the period 1986-1990 (population covered increased from 220,000 to 470,000) were used to calculate weekly rates of aggregated respiratory disease for persons of all ages and for elderly persons ( aged 65 years and over). The elderly respiratory disease rates and num bers of deaths were aggregated into 4-week periods; secular and season al trends were removed from each series and the two sets of residuals were examined graphically and cross correlation coefficients calculate d. There was a very strong positive association between the respirator y disease rate and number of deaths in the same 4-weeek period and the re was also a significant but less pronounced association between resp iratory disease in one 4-week period and deaths in the next. After pri or separation of weeks according to temperature into four bands, weekl y rates for respiratory disease were also strongly associated with the number of weekly deaths for each temperature band. The synchronisatio n of peaks and troughs in the two series throughout the year supports the hypothesis that a cause and effect relationship exists between res piratory disease in the elderly and number of deaths. Other climatic a nd meteorological variables besides temperature may play a part in det ermining the spread of a respiratory disease. There is a need for furt her research to identify the micro-organisms responsible for acute res piratory infections in the elderly.