Association Between Immunoparesis and Treatment Outcomes of Patients With Newly Diagnosed Multiple Myeloma: A Systematic Review and Meta-Analysis.

BACKGROUND

Immunoparesis, defined as suppression of uninvolved polyclonal immunoglobulins, occurs in up to 80% of patients with newly diagnosed multiple myeloma (NDMM). Infections are the second most common cause of mortality in this population, yet evidence regarding prognostic impact of immunoparesis in NDMM remains unclear.

MATERIALS AND METHODS

Using a prepublished protocol (CRD42022308687), we searched seven bibliographic databases from inception to February 2023 for studies reporting the impact of immunoparesis on clinical outcomes among adults with NDMM. The primary outcome of interest was overall survival (OS) and secondary outcomes were progression free survival (PFS) and infection risk. Effect sizes were quantified in terms of hazards ratio (HR) and pooled across studies using a random effects restricted maximum likelihood method. Heterogeneity was assessed using Cochran Q and the I statistic. Publication bias was assessed using contour enhanced funnel plots.

RESULTS

Of 5175 studies screened, 7 studies involving 6091 patients met our search criteria. Immunoparesis was not associated with worse OS (pooled hazard ratio 1.30; 95% CI, 0.91-1.84; P-value .11), with significant heterogeneity among the studies (I2 = 72.9%; Cochran's Q P-value .003). However, immunoparesis was associated with a significantly worse PFS (pooled hazard ratio 1.42; 95% CI 1.11-1.82; p value 0.013), with moderate heterogeneity (I2 statistic = 51%; Cochran's Q P-value .056). Infection rates were not uniformly reported precluding meta-analysis. Visual examination of funnel plot revealed the possibility of publication bias.

CONCLUSION

Overall, our findings suggest that immunoparesis did not have a detrimental impact on OS, but was associated with a significantly shorter PFS. Further studies are needed to understand the complexity of immune system perturbations in NDMM.