August 21, 1987

Isoniazid Prophylaxis

Author Affiliations

Harbor-UCLA Medical Center Torrance, Calif

Harbor-UCLA Medical Center Torrance, Calif

JAMA. 1987;258(7):910-911. doi:10.1001/jama.1987.03400070048023

To the Editor.—  The recent Letters to the Editor1-3 regarding the article entitled "The Age Threshold for Isoniazid Chemoprophylaxis,"4 while raising important points, do not mention a significant technical deficiency in the original article. The authors stated that they used the figure of 0.578 deaths per 1000 isoniazid recipients as the death rate for persons aged 35 years and older. In the study from which these data came,5 there were eight deaths among 8138 persons aged 35 years and older, giving a death rate of 0.983 deaths per 1000 isoniazid recipients. If this latter figure is used, it increases the risk of fatalities among persons aged 35 years and older taking isoniazid by 70% and markedly decreases the benefit-risk ratio for these persons.Furthermore, the Letters to the Editor did not point out another important consideration. A significant number of tuberculosis deaths occur in loners or dropouts