Digitalis therapy in a 70-year-old population.

In the population study "70-year-old people in Gothenburg" 14% of the probands were found to be undergoing treatment with digitalis, 6% with digoxin, 6% with digitoxin and 2% with other glycosides. A comparison between results of the interview method and those of S-digoxin analyses indicates that the interview method was acceptable. As far as can be judged from S-digoxin analyses, only about 60% of the treated patients were on a dosage considered to be effective and free from obvious risks of side-effects. Out of the 130 70-year-olds who were on digitalis treatment, 37% had obvious symptoms of heart disease requiring such treatment, 34% lacked symptoms of arrhythmia and/or congestive failure but had heart volumes larger than those used as reference values in younger age groups, and 29% had no symptoms indicating digitalis treatment. At least 13% of the population had indications for digitalis therapy and about 75% of those apparently needing digitalis were on such treatment. Thus both over- and underdiagnosis of heart disease requiring digitalis therapy were common in this age group.