Table 4

Linear mixed effect models for the clinical SELENA-SLEDAI and PGA in the presence of chronically low or normal C3/C4 or fluctuating C3/C4

Outcome variableC3/C4
status
n/study visitsIntercept
(SE)
Slope
(SE)
P valueMarginal R2 (%)
EC4d
(log net MFI)
Clinical
SELENA-SLEDAI
Low40/2083.48±1.500.77±0.460.0972.6
Normal57/1930.47±0.971.55±0.44<0.0019.0
Low or normal97/4011.60±0.791.20±0.29<0.0017.9
Fluctuating27/2110.17±1.981.38±0.600.0223.8
PGALow40/2100.79±0.200.15±0.060.0185.3
Normal57/1970.50±0.180.22±0.080.0095.2
Low or normal97/4070.59±0.120.19±0.04<0.0018.7
Fluctuating27/2120.70±0.270.13±0.080.1281.9
Anti-dsDNA
(log titres)
Clinical
SELENA-SLEDAI
Low40/2070.32±1.281.16±0.25<0.00120.0
Normal57/1902.55±1.000.40±0.330.2282.0
Low or normal97/3970.90±0.661.00±0.016<0.00120.8
Fluctuating27/210−1.78±1.781.47±0.039<0.00118.9
PGALow40/2090.76±0.180.10±0.030.0048.4
Normal57/1940.59±0.170.12±0.060.0325.5
Low or normal97/4030.66±0.100.11±0.02<0.00112.3
Fluctuating27/2120.79±0.221.07±0.050.1522.8
Anti-C1q
(log titres)
Clinical
SELENA-SLEDAI
Low40/2072.57±1.341.02±0.380.0085.4
Normal57/1921.89±0.791.02±0.400.0137.1
Low or normal97/3991.93±0.641.12±0.24<0.00110.8
Fluctuating27/2120.41±1.381.56±0.45<0.0018.7
PGALow40/2090.67±0.180.18±0.05<0.0019.5
Normal57/1960.77±0.140.10±0.070.1802.1
Low or normal97/4050.67±0.100.17±0.03<0.00110.8
Fluctuating27/2130.78±0.180.12±0.060.0553.1
  • Intercept, slope estimates (SE) and p value with marginal R2 are given. Of the 124 patients studied, 97 presented with either chronically low C3/C4 (n=40, followed for 9.2±0.3 visits) or normal C3/C4 at all visits (n=57, followed for 5.4±0.3 visits) and 27 presented with fluctuating C3/C4 (followed for 10.4±0.3 visits).

  • dsDNA, double-stranded DNA; EC4d, erythrocyte-bound C4d;  MFI, mean fluorescence intensity; PGA, Physicians Global Assessment; SELENA-SLEDAI, Safety of Estrogens in Lupus Erythematosus National Assessment— SLE Disease Activity Index.