Table 2 Univariable and multivariable Cox regression analysis of the four-lncRNA signature and overall survival in each dataset

lncRNA-focus risk score

2.718

1.937–3.815

7.262E-09

2.066

1.395–3.060

2.94E-04

Age

1.032

1.008–1.056

0.008

1.020

0.997–1.044

0.090

Gender (female/male)

0.844

0.556–1.280

0.424

1.047

0.665–1.648

0.842

Total Therapy (TT2/TT3)

0.914

0.572–1.462

0.709

1.060

0.648–1.735

0.816

IgA isotype (N/Y)

1.044

0.654–1.666

0.857

1.032

0.794–2.134

0.295

Serum beta 2-microglobulin ≥ 3.5 mg/L (N/Y)

2.677

1.742–4.112

6.99E-06

1.733

1.057–2.843

0.029

C-reactive protein ≥ 8.0 mg/L (N/Y)

1.749

1.155–2.648

0.008

1.008

0.628–1.616

0.975

Creatinine ≥ 2.0 mg/dL (177 μmol/L) (N/Y)

3.821

2.338–6.245

8.84E-08

1.864

0.992–3.501

0.053

Lactate dehydrogenase > upper limit of normal (>190 U/L) (N/Y)

2.651

1.749–4.017

4.33E-06

1.484

0.928–2.371

0.099

Serum albumin <35 g/ L (N/Y)

2.003

1.228–3.266

0.005

1.559

0.929–2.618

0.093

lncRNA-focus risk score

1.579

1.099–2.270

0.014

1.726

1.113–2.675

0.015

Age

1.015

0.991–1.039

0.223

1.006

0.982–1.031

0.616

Gender (female/male)

1.130

0.722–1.768

0.593

1.667

0.981–2.831

0.059

Total Therapy (TT2/TT3)

0.651

0.368–1.150

0.139

0.590

0.329–1.060

0.077

IgA isotype (N/Y)

1.189

0.724–1.953

0.494

1.428

0.837–2.438

0.192

Serum beta 2-microglobulin ≥ 3.5 mg/L (N/Y)

1.866

1.206–2.888

0.005

1.470

0.886–2.437

0.136

C-reactive protein ≥ 8.0 mg/L (N/Y)

1.233

0.786–1.932

0.362

1.158

0.734–1.828

0.529

Creatinine ≥ 2.0 mg/dL (177 μmol/L) (N/Y)

1.774

0.937–3.359

0.078

0.954

0.467–1.946

0.896

Lactate dehydrogenase > upper limit of normal (>190 U/L) (N/Y)

1.993

1.283–3.097

0.002

1.918

1.133–3.249

0.015

Serum albumin <35 g/ L (N/Y)

1.877

1.055–3.340

0.032

1.791

0.933–3.437

0.080

lncRNA-focus risk score

2.099

1.638–2.688

4.404E-09

1.905

1.434–2.530

8.65E-06

Age

1.024

1.007–1.041

0.005

1.013

0.996–1.030

0.128

Gender (female/male)

0.973

0.717–1.319

0.860

1.338

0.955–1.875

0.090

Total Therapy (TT2/TT3)

0.797

0.556–1.143

0.218

0.805

0.554–1.168

0.254

IgA isotype (N/Y)

1.106

0.787–1.555

0.561

1.261

0.888–1.791

0.194

Serum beta 2-microglobulin ≥ 3.5 mg/L (N/Y)

2.236

1.651–3.028

2.0E-07

1.574

1.111–2.231

0.011

C-reactive protein ≥ 8.0 mg/L (N/Y)

1.485

1.097–2.011

0.011

1.123

0.818–1.543

0.474

Creatinine ≥ 2.0 mg/dL (177 μmol/L) (N/Y)

2.730

1.856–4.015

3.35E-07

1.377

0.877–2.160

0.165

Lactate dehydrogenase > upper limit of normal (>190 U/L) (N/Y)

2.317

1.714–3.133

4.77E-08

1.645

1.180–2.294

0.003

Serum albumin <35 g/ L (N/Y)

1.946

1.342–2.821

4.47E-04

1.519

1.028–2.245

0.036

lncRNA-focus risk score

2.640

1.013–6.879

0.047

lncRNA-focus risk score

1.637

1.107–2.42

0.014

1.909

1.269–2.870

0.002

Age

1.014

0.998–1.03

0.087

1.016

0.999–1.032

0.054

Gender (female/male)

1.334

0.961–1.853

0.086

1.543

1.098–2.169

0.012