Prevalence of MGUS in a geriatric population in Turkey

Abstract

17564 Background: In this study, we aimed to investigate the prevalence of monoclonal gammopathy of unknown significance (MGUS) in the geriatric population in Turkey, with their clinical and laboratory parameters. Methods: The study group consisted of all individuals who applied to the outpatient clinic of Geriatrics Department between January-December 2005 in Hacettepe University Hospital in Ankara, Turkey. This clinic serves patients older than 65 years of age either with various acute/chronic diseases or healthy individuals for check-up purposes. All the participants had serum protein electrophoresis (SPE) -and immunofixation as needed- along with their routine laboratory tests and bone mineral density (BMD) measurements. Patients with a monoclonal protein in their SPEs were further evaluated for the presence of multiple myeloma. Clinical and laboratory parameters of patients with MGUS were compared with a control group of randomly selected 100 individuals who did not have MGUS. Results: A total of 1012 patients were enrolled in the study. Monoclonal band was detected in 22 patients (2.17%). The majority of the M proteins (63%) were of Ig G type. Of the remainder, 32% were Ig A, and 5% Ig M. Further investigations in these patients depicted one patient to have multiple myeloma and one patient to have lung carcinoma. The remaining 20 patients were diagnosed as MGUS (1.97%). BMD measurements of the patients with MGUS were significantly lower than the control group. Median lumbar BMD t score was -2.66 (Interquartile range (IQR): −.72 −3.77) in MGUS patients and -1.76 (IQR: −0.50 −2.47) in controls (p = 0.007). The two groups were found to be comparable in terms of comorbid diseases and other laboratory parameters. Conclusions: The prevalence of MGUS above the age of 25 is 1%, above 50 it is 1.7%, and above 70 it is approximately 3%. In our study, the frequency of MGUS above 65 years of age was found to be 1.97%, which is a little lower than the above quoted figures. It must be noted that our study group was not population-based and chronic diseases may be more common than the general population, resulting in a higher prevalence of MGUS. Another finding was the lower BMD measurements in patients with MGUS. BMD data is limited in patients with MGUS in the literature and further studies are needed to elucidate whether there is an association or not. No significant financial relationships to disclose.