School of Public Health, University of Haifa, Haifa, Israel.
Department of Quantitative Health Sciences, Mayo Clinic, Rochester, MN, USA.
Blood Cancer J. 2022 Apr 19;12(4):67. doi: 10.1038/s41408-022-00659-9.
Monoclonal gammopathy of undetermined significance (MGUS) is a premalignant clonal disorder that progresses to multiple myeloma (MM), or other plasma-cell or lymphoid disorders at a rate of 1%/year. We evaluate the contribution of body mass index (BMI) to MGUS progression beyond established clinical factors in a population-based study. We identified 594 MGUS through a population-based screening study in Olmsted County, Minnesota, between 1995 and 2003. Follow-up time was calculated from the date of MGUS to last follow-up, death, or progression to MM/another plasma-cell/lymphoid disorder. BMI (kg/m < 25/≥25) was measured close to screening date. We used Cox regression to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association of BMI ≥ 25 versus BMI < 25 with MGUS progression and also evaluated the corresponding c-statistic and 95% CI to describe discrimination of the model for MGUS progression. Median follow-up was 10.5 years (range:0-25), while 465 patients died and 57 progressed and developed MM (N = 39), AL amyloidosis (N = 8), lymphoma (N = 5), or Waldenstrom-macroglobulinemia (N = 5). In univariate analyses, BMI ≥ 25 (HR = 2.14,CI:1.05-4.36, P = 0.04), non-IgG (HR = 2.84, CI:1.68-4.80, P = 0.0001), high monoclonal (M) protein (HR = 2.57, CI:1.50-4.42, P = 0.001), and abnormal free light chain ratio (FLC) (HR = 3.39, CI:1.98-5.82, P < 0.0001) were associated with increased risk of MGUS progression, and were independently associated in a multivariable model (c-statistic = 0.75, CI:0.68-0.82). The BMI association was stronger among females (HR = 3.55, CI:1.06-11.9, P = 0.04) vs. males (HR = 1.39, CI:0.57-3.36, P = 0.47), although the interaction between BMI and sex was not significant (P = 0.15). In conclusion, high BMI is a prognostic factor for MGUS progression, independent of isotype, M protein, and FLC. This association may be stronger among females.
意义未明的单克隆丙种球蛋白血症（MGUS）是一种克隆性疾病，具有恶性倾向，每年有 1%的患者进展为多发性骨髓瘤（MM）或其他浆细胞或淋巴细胞疾病。我们在一项基于人群的研究中评估了体质指数（BMI）对 MGUS 进展的贡献，超过了既定的临床因素。我们通过明尼苏达州奥姆斯特德县的一项基于人群的筛查研究，在 1995 年至 2003 年间确定了 594 例 MGUS。随访时间从 MGUS 确诊日期计算至最后一次随访、死亡或进展为 MM/另一种浆细胞/淋巴细胞疾病。BMI（kg/m²<25/≥25）在筛查时附近测量。我们使用 Cox 回归估计 BMI≥25 与 BMI<25 与 MGUS 进展之间的风险比（HR）和 95%置信区间（CI），并评估了相应的 C 统计量和 95%CI，以描述用于 MGUS 进展的模型的区分能力。中位随访时间为 10.5 年（范围：0-25），57 例患者死亡，57 例进展并发生 MM（N=39）、AL 淀粉样变性（N=8）、淋巴瘤（N=5）或华氏巨球蛋白血症（N=5）。在单变量分析中，BMI≥25（HR=2.14，CI：1.05-4.36，P=0.04）、非 IgG（HR=2.84，CI：1.68-4.80，P=0.0001）、高单克隆（M）蛋白（HR=2.57，CI：1.50-4.42，P=0.001）和异常游离轻链比（FLC）（HR=3.39，CI：1.98-5.82，P<0.0001）与 MGUS 进展风险增加相关，并且在多变量模型中独立相关（C 统计量=0.75，CI：0.68-0.82）。BMI 与女性（HR=3.55，CI：1.06-11.9，P=0.04）而非男性（HR=1.39，CI：0.57-3.36，P=0.47）的相关性更强，尽管 BMI 与性别之间的交互作用无统计学意义（P=0.15）。总之，高 BMI 是 MGUS 进展的预后因素，独立于同种型、M 蛋白和 FLC。这种关联在女性中可能更强。
