Demographic data
The table summarizes demographic and clinical features of the NPSLE patients. Twenty-six patients (19 females, 73.07%; 7 males, 26.93%), with mean age of 43.19 years (SD 11.33; 95% CI 38.61–47.77), ranging from 20 to 70 years, were evaluated. Sixteen women had normal pregnancy (69.56%), one had abortion (4.36%), and six were nulliparous (26.08%). Most patients were self-declared white (n = 17; 65.38%), followed by mixed race, brown color, and black (non-white; n = 9; 34.62%). The patient's mean age at onset of SLE was 26,05 (SD 11,04) years, ranging from 8 to 51 years, and for NPSLE was 42.29 (SD 13,49) years, ranging from 11 to 59 years. The mean time between the onset of SLE and first NPSLE symptoms was 5.57 (SD 5.02) years, ranging from zero to 22 years. The disease has already been initiated as NPSLE in 4 patients (15.38%).
Clinical and laboratory data
The average score on SLEDAI was 31.69 (SD 10.33; 95% CI 27.51–35.86), ranging from 11 to 51 scores, and the SLICC/ACR-DI score was 6.96 (SD 2.37; 95% CI 6.00-7.92), ranging from 2 to 11 scores. The patients underwent an average of 9.23 pulse therapy sessions (SD 3.12; 95% CI 7.96–10.49), ranging from 4 to 15 sessions.
Seventeen 17 (65.38%) patients presented psychosis, 01 (3.84%) bipolar disorder, 07 (26.92%) depression, 02 (7.69) vasculitis, 08 (30.77) seizure, 06 (23.07) anxiety, 02 (7.69) headache, 01 (3.84) epilepsy and 01 (3.84) stroke.
All patients underwent Native anti-DNA and ANA laboratory tests. For Native anti-DNA and ANA, 13 (50%) and 19 (73.07%) patients were reactive, respectively. For ACA IgG and IgM, nine (30.76%) and 13 (50.09%) patients were positive, respectively. For anti-β2GPI IgG and IgM, five (31.25%) and seven (43.75%) patients were positive, respectively. For anti-SS-B (LA) and anti-SS-A (RO), one (14.29%) and three (30.00%) patients were also positive, respectively. Complement levels were altered in 11 (42.31%) patients for C3, and in 8 (30.77%) for C4.
SISCOM findings
The MRI was normal in 6 (23.08%) patients and abnormal or with nonspecific findings in another 20 (76.92%). SISCOM agreed with MRI findings in 13 patients (50.00%). None of the NP manifestations correlated with the SISCOM findings. Ie., the evolution of rCBF changes (SISCOM) was not influenced by the type of NP manifestation.
Regarding the SISCOM findings, 15 (57.69%) patients presented improvement, 12 (46.15%) activation, 8 (30.77%) deactivation and 6 (23.07%) presented worsening. These categories were not associated with the degree of activity [SLEDAI, Mann Whitney Test; improvement, U = 60.5000, p = 0.252; activation, U = 66,000, p = 0.353; deactivation, U = 51,500, p = 0.254 and worsening, U = 51,000, p = 0.583] or disease-related damage [SLICC, Mann Whitney Test; improvement, U = 65,500, p = 0.371; activation, U = 67,000, p = 0.375; deactivation, U = 47,500, p = 0.167 and worsening, U = 56,000, p = 0.805]. However, there was a trend towards an association between lower disease activity (SLEDAI 33.80) and improvement, and greater activity (SLEDAI 35.00) with worsening [Mann Whitney test, U = 56,000; p = 0.072]. There was also a trend of association between lower damage associated with LESNP (SLICC 6.73) with improvement, and greater damage (SLICC 7.83) with worsening rCBF (Mann Whitney test, U = 56,000, p = 0.085).
Binary logistic regression showed that the model containing female gender was significant for activation [X2(1) = 5.804; p = 0.041, R2 Negelkerke = 0.267] and worsening [X2 (1) = 9.781; p = 0.008, R2 Negelkerke = 0.475] in SISCOM, but not significant for amelioration and deactivation. The female gender was predictive of activation (OR = 0.091; IC 95% = 0.009–0.906) and worsening (OR = 28.333; IC 95% = 2.389–336.008), but not predictive of amelioration or deactivation. The model containing female gender was also significant for the finding set of deactivation and worsening [X2 (1) = 5.804; p = 0.041, R2 Negelkerke = 0.282], but not significant for the set of activation and worsening. The female gender was predictive of the deactivation and worsening set (OR = 11,000; IC 95% = 1,103–109,674), and not predictive of the activation and worsening set.
Binary logistic regression showed that the model containing non-white races was significant for worsening in the SISCOM [X2 (1) = 7,279; p = 0.020, R2 Negelkerke = 0.387], but not for amelioration, activation or deactivation. Non-white races were predictive of worsening in SISCOM (OR = 17,500; IC 95% = 1,560 − 196,319), but not predictive of improvement, activation or deactivation.
Binary logistic regression of the 24 patients who measured the presence of complement C3 showed that the model containing the normal result (RV 0.9–1.4 U / ml) was significant for improvement in SISCOM [X2 (1) = 7.279; p = 0.021, R2 Negelkerke = 0.303], but not for the worsening, activation or deactivation. Normal C3 was a significant predictor of improvement in SISCOM (OR = 8,889; IC 95% = 1,397 − 56,575), but not for worsening, activation or deactivation. Normal C4 was not a significant predictor of any SISCOM finding.
Binary logistic regression of the NP manifestations showed a trend between seizure and deactivation and worsening group [X2 (1) = 3.798; p = 0.062, R2 Negelkerke = 0.185 ; OR = 5.133; IC 95% = 0.922–28.570] and deactivation group [X2 (1) = 3.665; p = 0.096, R2 Negelkerke = 0.185 ; OR = 7.000; IC 95% = 0.709–69.121], but not for the amelioration, activation and worsening.