A gamopatia monoclonal de significado indeterminado (MGUS) está presente em cerca de 2% a 3% da população branca com 50 anos de idade ou mais.[5]Kyle RA, Larson DR, Therneau TM, et al. Long-term follow-up of monoclonal gammopathy of undetermined significance. N Engl J Med. 2018 Jan 18;378(3):241-49.
https://www.nejm.org/doi/10.1056/NEJMoa1709974
http://www.ncbi.nlm.nih.gov/pubmed/29342381?tool=bestpractice.com
[6]Wadhera RK, Rajkumar SV. Prevalence of monoclonal gammopathy of undetermined significance: a systematic review. Mayo Clin Proc. 2010 Oct;85(10):933-42.
https://www.mayoclinicproceedings.org/article/S0025-6196(11)60235-8/fulltext
http://www.ncbi.nlm.nih.gov/pubmed/20713974?tool=bestpractice.com
[7]Landgren O, Graubard BI, Katzmann JA, et al. Racial disparities in the prevalence of monoclonal gammopathies: a population-based study of 12,482 persons from the National Health and Nutritional Examination Survey. Leukemia. 2014 Jul;28(7):1537-42.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4090286
http://www.ncbi.nlm.nih.gov/pubmed/24441287?tool=bestpractice.com
A prevalência aumenta com a idade; estimativas cruas indicam que pode haver 3-5 milhões de norte-americanos afetados por MGUS. As MGUS são mais comuns em homens que em mulheres, afetando cerca de 3% dos homens brancos e cerca de 2% das mulheres brancas.[5]Kyle RA, Larson DR, Therneau TM, et al. Long-term follow-up of monoclonal gammopathy of undetermined significance. N Engl J Med. 2018 Jan 18;378(3):241-49.
https://www.nejm.org/doi/10.1056/NEJMoa1709974
http://www.ncbi.nlm.nih.gov/pubmed/29342381?tool=bestpractice.com
[6]Wadhera RK, Rajkumar SV. Prevalence of monoclonal gammopathy of undetermined significance: a systematic review. Mayo Clin Proc. 2010 Oct;85(10):933-42.
https://www.mayoclinicproceedings.org/article/S0025-6196(11)60235-8/fulltext
http://www.ncbi.nlm.nih.gov/pubmed/20713974?tool=bestpractice.com
[7]Landgren O, Graubard BI, Katzmann JA, et al. Racial disparities in the prevalence of monoclonal gammopathies: a population-based study of 12,482 persons from the National Health and Nutritional Examination Survey. Leukemia. 2014 Jul;28(7):1537-42.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4090286
http://www.ncbi.nlm.nih.gov/pubmed/24441287?tool=bestpractice.com
A MGUS é 2 a 3 vezes mais comum entre pessoas negras que entre pessoas brancas.[6]Wadhera RK, Rajkumar SV. Prevalence of monoclonal gammopathy of undetermined significance: a systematic review. Mayo Clin Proc. 2010 Oct;85(10):933-42.
https://www.mayoclinicproceedings.org/article/S0025-6196(11)60235-8/fulltext
http://www.ncbi.nlm.nih.gov/pubmed/20713974?tool=bestpractice.com
[7]Landgren O, Graubard BI, Katzmann JA, et al. Racial disparities in the prevalence of monoclonal gammopathies: a population-based study of 12,482 persons from the National Health and Nutritional Examination Survey. Leukemia. 2014 Jul;28(7):1537-42.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4090286
http://www.ncbi.nlm.nih.gov/pubmed/24441287?tool=bestpractice.com
[8]Landgren O, Weiss BM. Patterns of monoclonal gammopathy of undetermined significance and multiple myeloma in various ethnic/racial groups: support for genetic factors in pathogenesis. Leukemia. 2009 Oct;23(10):1691-7.
http://www.ncbi.nlm.nih.gov/pubmed/19587704?tool=bestpractice.com
[9]Landgren O, Katzmann JA, Hsing AW, et al. Prevalence of monoclonal gammopathy of undetermined significance among men in Ghana. Mayo Clin Proc. 2007 Dec;82(12):1468-73.
http://www.ncbi.nlm.nih.gov/pubmed/18053453?tool=bestpractice.com
Isso é compatível com os padrões observados para mieloma múltiplo. No entanto, a taxa de progressão de MGUS para mieloma múltiplo (cerca de 0.5% a 1% ao ano) é a mesma para pessoas negras e brancas.[10]Kyle RA, Therneau TM, Rajkumar SV, et al. Long-term follow-up of IgM monoclonal gammopathy of undetermined significance. Semin Oncol. 2003;30:169-171.
http://www.ncbi.nlm.nih.gov/pubmed/12720130?tool=bestpractice.com
[11]Landgren O, Gridley G, Turesson I, et al. Risk of monoclonal gammopathy of undetermined significance (MGUS) and subsequent multiple myeloma among African American and white veterans in the United States. Blood. 2006 Feb 1;107(3):904-6.
https://ashpublications.org/blood/article/107/3/904/22154/Risk-of-monoclonal-gammopathy-of-undetermined
http://www.ncbi.nlm.nih.gov/pubmed/16210333?tool=bestpractice.com
[12]Turesson I, Kovalchik SA, Pfeiffer RM, et al. Monoclonal gammopathy of undetermined significance and risk of lymphoid and myeloid malignancies: 728 cases followed up to 30 years in Sweden. Blood. 2014 Jan 16;123(3):338-45.
https://ashpublications.org/blood/article/123/3/338/32296/Monoclonal-gammopathy-of-undetermined-significance
http://www.ncbi.nlm.nih.gov/pubmed/24222331?tool=bestpractice.com
Embora os mecanismos biológicos subjacentes permaneçam obscuros, há evidências de heterogeneidade entre pacientes com MGUS de ascendências diferentes. Por exemplo, em comparação com pessoas brancas, pacientes negros com MGUS apresentam taxas de MGUS tipo imunoglobulina M (IgM) menores que as de imunoglobulina G (IgG) ou imunoglobulina A (IgA).
Foi relatada uma disparidade geográfica na prevalência de MGUS nos EUA: a prevalência ajustada de MGUS foi 3,1% no Norte/Meio-Oeste versus 2,1% no Sul/Oeste.[7]Landgren O, Graubard BI, Katzmann JA, et al. Racial disparities in the prevalence of monoclonal gammopathies: a population-based study of 12,482 persons from the National Health and Nutritional Examination Survey. Leukemia. 2014 Jul;28(7):1537-42.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4090286
http://www.ncbi.nlm.nih.gov/pubmed/24441287?tool=bestpractice.com