Changes in mortality by tuberculosis in non-industrialized Coimbra (Portugal): Trends between 1861 and 1914.

Considering that before antibiotics and vaccination the course of tuberculosis depended mostly on the patient's immune response, this study tested the hypothesis that the mortality profile remained similar during the transition from the 19th to 20th century. The biographical data of the individuals buried in the Coimbra Municipal Cemetery of Conchada were analysed, and the records of those who were born in the city and had tuberculosis registered as the cause of death were analysed using SPSS. The years of death were grouped: 1861-1870 (n = 124, 22.5%), 1871-1880 (n = 234, 42.4%), and 1910-1914 (5 years, n = 194, 35.1%). Mortality by tuberculosis has increased over the years. A total of 552 individuals, 242 females (43.8%) and 310 males (56.2%) died of tuberculosis (p < 0.05). The mean age at death (min = 11 days, max = 86 years) decreased over time, respectively 51.8, 53.1, and 35.8 years-old for individuals >20. Deaths by pulmonary tuberculosis (n = 38, 1861-1870; n = 115, 1910-1914) and meningeal tuberculosis (n = 0, 1861-1870; n = 48, 1910-1914) increased over time, whereas scrofula decreased (n = 23, 1861-1870; n = 3, 1910-1914). Only a 12 years-old male (0.2%) died of bone tuberculosis. Infant (0-3 years-old) mortality occurred mainly (50.5%,48/95) between July and October. The hypothesis tested was not confirmed. Death by tuberculosis has increased, which may be a consequence of population growth, deterioration of the living conditions, and/or changes in bacterial virulence and/or in the host immune system.