Prevalence of co-morbidity in lung cancer patients and its relationship with treatment: a population-based study

With the rising mean age of lung cancer patients, the number of patients with serious co-morbidity at diagnosis is increasing. As a result, co-morbidity may become an important factor in both the choice of treatment and survival. We studied the prevalence of serious co-morbidity among newly diagnosed lung cancer patients and its association with morphology, stage and treatment.

A total of 3864 lung cancer patients registered in the population-based registry of the Comprehensive Cancer Centre South between 1993 and 1995.

During the study period, the mean age of patients was 67 years (range: 29-93). The most frequent concomitant diseases were cardiovascular diseases (23%), chronic obstructive pulmonary diseases (COPD) (22%) and other malignancies (15%). The prevalence of concomitant diseases was highest for men (60%), patients with squamous-cell carcinoma (64%) and those with a localised tumour (66%). The resection rate for patients < 70 years, with a localised non-small-cell lung tumour, was especially low for those with COPD (67%) or diabetes (64%) compared with patients without concomitant diseases (94%). The association between co-morbidity and chemotherapy for patients with small-cell lung cancer was limited.

The prevalence of co-morbidity, especially cardiovascular diseases and COPD, among lung cancer patients is about twice as high as in the general population. Co-morbidity seems to be associated with earlier diagnosis of lung cancer, but it may also lead to less accurate staging and less aggressive treatment. Thus, prognosis is likely to be negatively influenced by co-morbidity.