Comparison of interview-based and medical-record based indices of comorbidity among breast cancer patients

OBJECTIVES: To compare patient interview-based and medical-record based measures of comorbidity and their relation to primary tumor therapy, all cause mortality, self-reported upper body function, and overall physical function. METHODS: Three-hundred and three breast cancer patients (> or = 55 years) who were diagnosed in 1 of 5 Boston hospitals were enrolled. Patient interviews and medical record abstracts provided the information necessary to construct the Charlson index, Satariano index, and a new interview-based index of cardiopulmonary comorbidity. Those indices were used alone and in combination to predict the patient outcomes. RESULTS: The indices of comorbidity corresponded well with one another. No index of comorbidity predicted mortality or receipt of definitive primary therapy. The new interview-based index of cardiopulmonary comorbidity was a better predictor of upper body function and overall physical function than was the interview-based or medical record-based Charlson or Satariano indices of comorbidity. CONCLUSION: Older breast cancer patients are able to provide information about their diseases and related symptoms that correlates well with medical record-based measures of comorbidity and displays similar patterns of predictive power. A new self-reported measure of cardiopulmonary comorbidity performs better than the medical record-based measures for predicting patient related functional outcomes.