Mortality and Morbidity in Birmingham during the 1976 Heatwave

The total deaths by day in Birmingham were analysed in relation to several weather variables from 24 June to 8 July, 1976 when the mean daily dry-bulb temperature remained continuously above 22°C, and for the preceding and following cooler fortnights. The average number of daily deaths reported to the Registrar increased significantly by nearly 20 per cent during this hot fortnight and by over 30 per cent from 3 to 5 July. The excess deaths were mainly of elderly men and women with cardiovascular or cerebrovascular disease. The daily mortality correlated best with the maximum daily drybulb temperature and then with the mean temperature compared with the five other weather variables tested. The mean wet-bulb temperature on days one and three before death was the only measure of humidity tested to correlate significantly with daily deaths. The smaller number of these deaths which were also reported to the Coroner were analysed separately. There was a threefold and statistically significant increase during the heatwave in deaths of women aged 70 to 79, but deaths of men in this age group and of men and women over 80 did not increase. There was a notable increase in deaths from violence of men aged 20 to 39. Morbidity in the working population, judged by new sickness benefit claims, did not increase during the hot weather. There were significantly more hospital emergency admissions from 24 June to 8 July 1976 than for the same period in 1975 or 1974. Episodes of sickness in two large Birmingham general practices showed a modest increase.