Nasal polyps. A clinical study of endoscopic score systems and epidemiology

Abstract

Introduction: Nasal polyps are a common disease, the etiology and pathogenesis of which are still unclear. For diagnosis, a nasal endoscope is essential, while for follow-up treatment, a reliable score system is necessary. The existing score systems consist of few score steps and measure only large changes in polyp size. The question is whether a score system with a continuous scale will provide more reproducible, and sensitive results. The epidemiology of nasal polyps in the general population is not known. The main aims of this work were; to develop a sensitive and reliable method for assessing the size and extension of nasal polyps, and to determine the prevalence of nasal polyps in a general population.Methods: Different score systems, three newly developed and two established, were compared with regard to their ability to assess polyp size and detect changes during medical treatment. A total of 150 adult patients with nasal polyps were investigated in these studies. The new score systems used were: lateral imaging (LI), assessment of polyp obstruction, and nasal airway patency. The established score systems were ad modum Lildholdt et al. and ad modum Lund and Mackay. The score systems were compared with the patients' subjective symptoms. A nasal endoscope was used to get a good view of polyps in the entire nasal cavity. One investigator examined the patients twice, whereafter three otorhinolaryngologists examined 30 patients independently of each other, using the same technique and performing the investigations under the same conditions. Thereafter, the different methods of polyp staging were compared. The sensitivity of LI in comparison with the Lildholdt et al. score system was tested by measuring early (i.e., within 14 days), and small, changes in polyp size during treatment with a topical corticosteroid. In the epidemiological study, 1,900 adult subjects were randomly drawn from a small town register. Of these, 1,387 were examined with a nasal endoscope, tested for smell impairment, and questioned with regard to relevant medical conditions. Health-related quality of life (HRQL) was investigated among individuals diagnosed with nasal polyps and compared with that of individuals without nasal polyps and patients with symptomatic nasal polyps.Results: The reproducibility of all five score systems was good and the reliability between different investigators was significantly better for score systems LI, Lildholdt et al., and assessment of polyp obstruction than for the other two. The LI was significantly more sensitive and better able than the Lildholdt et al. score system to detect early changes in polyp size. The symptom score showed significant improvement after 3 days. The prevalence of nasal polyps in adults was 2.7%, and was more frequent among men and asthmatics, as well as with increasing age. The individuals with nasal polyps experienced the same frequency of asthma and reduced sense of smell as patients, and had impaired HRQL.Conclusion: Lateral imaging, evaluated by nasal endoscopy, has been shown to have good reproducibility and to be a reliable method for detecting early changes in polyp size. The prevalence of nasal polyps was 2.7% in the general adult population studied. Nasal polyps lead to reduced HRQL. Nasal polyps are a manifestation of a mucosal disease including both the upper and the lower airways.