A longitudinal study of idiopathic exudative lymphocytic pleural effusion in older people.

OBJECTIVES: To assess the long-term prognosis of older patients with idiopathic exudative lymphocytic pleural effusion.

DESIGN: Prospective observational study.

SETTING: A university-affiliated tertiary care center.

PARTICIPANTS: Forty-seven consecutive patients (aged 74.9+/-5.4) with idiopathic exudative lymphocytic pleural effusion were enrolled over a 42-month period.

MEASUREMENTS: Baseline sociodemographic information, clinical data, and Charlson Comorbidity Index score were obtained. After an exhaustive examination, clinical evaluation and periodic chest radiographs were taken until one of the endpoints was met: complete resolution of the pleural effusion, death from all causes, or the end of the study period.

RESULTS: The mean follow-up period was 16.3+/-17.0 months. During the course of the study, complete resolution of the pleural effusion occurred in 17% of the patients, whereas it remained stable in 45%, and progressed in 38%. In seven cases, the cause of the effusion was established after an average of 84 days, and in another two, the diagnosis was made postmortem. Malignancy was documented in eight of the nine cases. Although the burden of comorbidities and cardiac function at baseline were similar in the three categories, the 3-year survival rate was 63%, 5%, and 0%, respectively. None of the patients developed active tuberculosis, although 15% had positive tuberculin test.

CONCLUSION: By categorizing the presence of idiopathic effusion into resolving, persistent, or progressive, this study may provide a more practical approach to the long-term prognosis of older patients with idiopathic exudative lymphocytic effusion who refuse or are considered too frail to undergo an invasive procedure.