Systemic lupus erythematosus in North Indian Asians. A prospective analysis of clinical and immunological features

Role of interleukin-6 and interferon-α in systemic lupus erythematosus: A case-control study and meta-analysis

BACKGROUND

Systemic lupus erythematosus (SLE) is an autoimmune disorder affecting various organ systems with unknown etiology. Interleukin-6 (IL-6) and interferon-alpha (IFN-α) have been shown to have a major role in disease pathogenesis, and they correlate with SLE disease activity, but reports in the literature are conflicting. The present study aims to investigate the significance of IL-6 and IFN-α levels in SLE pathogenesis in an eastern Indian cohort.

MATERIAL AND METHODS

70 SLE patients fulfilled SLICC 2012 criteria, and 40 age- and gender-matched healthy controls (HC) were enrolled. Baseline characteristics along with disease activity were recorded for all patients. Levels of IL-6 and IFN-α were measured by using ELISA. For the meta-analysis, published articles were searched through different databases. Two independent researchers extracted data, and the meta-analysis was performed with CMA v3.1.

RESULTS

The plasma levels of IL-6 and IFN-α in SLE patients were significantly elevated compared to HC (IL-6: p < .0001, IFN-α: p = 0.01). SLEDAI score correlated positively with plasma IL-6 (p < .0001, r = 0.46) and IFN-α levels (p < .0001; r = 0.47). Meta-analysis of previous reports, including our case-control data, revealed higher IL-6 (p < .0001) and IFN-α (p = .005) in SLE patients compared to HC. Furthermore, IL-6 (p < .0001, r = 0.526) and IFN-α (p < .0001; r = 0.371) levels positively correlated with the disease activity.

CONCLUSION

IL-6 and IFN-α levels are elevated in SLE and they correlate with disease activity. Further studies with a larger sample size in different populations are required to validate our findings.

Indian SLE Inception cohort for Research (INSPIRE): the design of a multi-institutional cohort

Systemic lupus erythematosus (SLE) cohorts across the world have allowed better understanding of SLE, including its bimodal mortality, and the impact of social factors and ethnicity on outcomes. The representation of patients from South Asia has been poor in the existing SLE cohorts across the world. Hence, we planned to initiate an inception cohort to understand the diversity of lupus in India. Indian SLE Inception cohort for REsearch (INSPIRE), planned over 5 years is a multi-centric cohort of adult and childhood lupus patients of Indian origin, fulfilling the SLICC-2012 classification criteria, with an aim to provide cross-sectional information on demography, ethnicity, socio-economic status, standard disease variables, quality of life, and prospective information on new events like hospitalization, infections, pregnancies, changes in disease activity, and damage. One of the other deliverables of this project is the establishment of a biorepository. The instruments to be used for each variable and outcome were finalized, and a web-enabled case report form was prepared to encompass SLEDAI, BILAG, SLICC damage scores, and Lupus quality-of-life index.Ten centers located in different geographic areas of India would enroll patients who are seen for the first time after the start of the study. In the first 8 months, 476 patients (63 children, 36 males) have been enrolled with a median disease duration of 10 (IQR 4-17) months and mucocutaneous features being the most prevalent clinical manifestations. INSPIRE is the first prospective Indian SLE cohort to study the diversity of Indian patients.

Cardiovascular co-morbidity in Asians with lupus: theoretical concern or clinical reality?

Immuno-inflammatory diseases like lupus are associated with premature atherosclerosis. With improved survival, atherosclerotic cardiovascular disease has emerged as an important late complication of systemic lupus erythematosus. The burden of this co-morbidity in Asian patients is not fully known but is likely to be high. We review the literature available and draw attention to this oft overlooked problem.

Surviving the butterfly and the wolf: mortality trends in systemic lupus erythematosus

OBJECTIVE

To address changes in survival of patients with systemic lupus erythematosus (SLE) and to compare mortality statistics with associated disease specific as well as comorbid conditions.

METHODS

Review of the international literature on survival of patients with SLE.

RESULTS

During the first half of the 20th century, SLE was considered a rapidly progressive and almost invariably fatal disease. Since the 1950s, the estimated 5-year survival of SLE patients in developed countries rose from <50% to >95% and similar increases were seen in 10-year survival. Mortality rates of SLE patients, however, remain approximately 3 times that of an age- and sex-matched population in most studies, indicating that death still occurs prematurely in a substantial portion of patients, albeit later in the disease course. This improved prognosis does not appear to have been shared equally by all racial/ethnic groups. This appears to be attributable more to socioeconomic and sociocultural factors than to true differences in disease manifestations. Along with the increased survival of SLE patients, there has been a change in the causes of death. Most notably, there has been a dramatic increase in the proportionate mortality from vascular disease, particularly accelerated atherosclerosis. Both disease and therapeutic modalities, in particular corticosteroids, appear to contribute to the high prevalence of coronary artery disease (CAD).

CONCLUSIONS

Much progress has been made in improving the survival of SLE, but there is need for further improvement. Aggressive treatment of risk factors for CAD is advisable, but it remains to be assessed to what extent such interventions can further reduce mortality.

Systemic lupus erythematosus in Aborigines and Caucasians in central Australia: a comparative study

The objective of this study was to determine whether there are differences in the prevalence, clinical and laboratory manifestations, and morbidity and mortality of systemic lupus erythematosus (SLE) between Aborigines and Caucasians in Central Australia. The medical records of all patients diagnosed with SLE upto December 1999 were reviewed retrospectively. Prevalence of SLE was 1:1360 for Aborigines and 1:5170 for Caucasians. The prevalences of malar rash, discoid rash, photosensitivity, oral ulcers, pleuritis, anticardiolipin antibodies and lupus anticoagulant were higher in Caucasians than in Aborigines. The prevalences of anti-Sm antibody and anti-RNP antibody were higher in Aborigines than in Caucasians. These differences did not attain statistical significance. There was a low prevalence of renal disease in Aborigines and Caucasians. Mortality was low in Aborigines and nil in Caucasians. Although there is a high prevalence of SLE in Aborigines in Central Australia, renal involvement and mortality are low.

Survival analysis of 306 European Spanish patients with systemic lupus erythematosus

OBJECTIVE

To describe survival of lupus in South European Spanish patients.

PATIENTS AND METHODS

Observational study of all SLE Spanish patients seen at three University Hospitals between 1975 and 1993. The charts of all patients were retrospectively reviewed. Sixty-four clinic and laboratory variables were extracted from charts. Univariate analysis, multivariate Cox proportional hazard regression analysis, actuarial life tables and multiple logistic regression analysis were used to calculate survival probability and identify variables associated with survival.

RESULTS

Three hundred and six (275 female and 31 male) patients were identified. Their mean age at diagnosis was 31.9 years (range 4 to 85). The mean duration of followup was 79 (1-126) months. Thirty-one patients died. The most common cause of death was infection (29%). Five, 10 and 15 years' survival rate was 90%+/-0.0158, 85%+/-0.0262 and 80%+/-0.0413, respectively. Log-rank analysis showed that male sex, proteinuria and nephropathy at diagnosis were associated with poor survival. By univariate and multivariate analysis male gender, nephropathy and CNS involvement were associated with worse survival.

CONCLUSION

In SLE patients from Spain, rate of survival is similar to other Caucasian patients, and better than other ethnic groups of Spanish ancestry. Other factors rather than genetic factors could explain our findings.

Systemic lupus erythematosus in India

The first case of systemic lupus erythematosus (SLE) was reported from India in 1995 followed by two more case reports and further, a series of eight cases, till 1969. Since the establishment of a clinical immunology laboratory at a major teaching institution in New Delhi in 1968, SLE was extensively studied and reported from that centre. From mid-1980 onwards several other centres in different regions in India including Chennai (old name Madras), Mumbai (old name Bombay), Calcutta and Hydrabad, also published their regional experience on SLE. Based on these data, the present report describes the clinical and laboratory characteristics of 1366 SLE patients seen in different regions of India. Arthritis, rash, photosensitivity, seizures and psychosis were seen in comparable proportions to other racial groups. Similarly, ANA and anti-DNA antibody positivity was also within the range seen in other racial groups. When compared with other series, however, alopecia, renal lupus, oral ulcers and neurological involvement was seen in higher proportions, reaching statistically significant figures in comparison to some racial groups. In contrast, haematological manifestations were seen in significantly less proportions in comparison to some of the racial groups. Serositis and discoid lesions were also seen in lower proportions than in most of other races. The proportion of those with anti-Sm antibodies was in between two extremes of highest among Africans and Israelis and lowest among Chinese and Europeans. Other manifestations were comparable to most other racial groups. Compared to North American and European reports, significantly low 5 and 10 year survival was observed among patients from India. This could be related to the general public health situation in the country including less than optimal management facilities in hospitals, delay in diagnosis due to lack of awareness of the disease, referral bias where only serious patients reach major city hospitals, or a truly severe disease among Indians, or a combination of these genetic, environmental and/or sociocultural factors. The Main causes of death were irreversible renal damage, infections and neurological involvement. Despite a comparable prevalence of anticardiolipin antibodies (aCL) and lupus anticoagulants (LAC), clinical antiphospholipid syndrome was significantly less common. Genetic studies showed appreciable increase of HLA DR4 (37.5%) among patients compared with controls (18%). Additionally the haplotype B8-DR3 was encountered frequently in the patient group.

Serological characteristics of systemic lupus erythematosus from a hospital-based rheumatology clinic in Kuwait

Thirty-one consecutive patients with SLE were screened for antinuclear antibody (ANA), anti-DNA antibodies, extractable nuclear antigen antibodies (anti-ENAs) including anti-Sm, anti-RNP, anti-SSA (anti-Ro), anti-SSB; (anti-La), anti-Scl-70, rheumatoid factor (RF), C-reactive protein (CRP), C3 and C4 levels, anti-cardiolipin antibodies (aCL), biologically false positive serological test for syphilis (BF-STS) using VDRL test and Coombs' test. The age of the patients ranged from 11 to 52 year with a median of 29 year; female to male ratio of 5:1. There were 21 Kuwaitis, four Egyptians, three from the Indian subcontinent, two Filipinos and one Syrian. Main clinical categories of SLE were: mild cutaneous SLE in 12 (38.7%), clinical antiphospholipid syndrome (APS) secondary to SLE in 8 (25.8%), haematological manifestations of SLE in 5 (16.1%), renal lupus in four (12.9%), neuropsychiatric in three (9.7%), others (6.4%). Clinical features overlapped in several patients. ANA was positive in 96.8% (mean value 891.61 units/ml), anti-DNA in 35.5% (mean value 56.4 units) that was lower than expected and could be due to selection bias as the patients were from a rheumatology clinic, anti-ENA in 42%, anti-Sm 13% that was lower than other non-Caucasian populations, anti-RNP 13%, anti-SS-A in 35.5%, anti-SS-B in 19.4%, Scl-70 in 13%, CRP in 71% (moderate 58%, very high 13%); C3 mean 1.52 mg/ml (3.2% low levels), C4 mean 0.35 mg/ml (32% low levels), anticardiolipin mean GPL 35.35 units (high 58%), mean MPL 10.61 units (high 26%), BF-STS in 6%, Coombs' test in 6%, RF positive in 36%. The only significant positive clinical associations observed were those of renal involvement with anti-DNA antibodies (P = 0.042), and clinical antiphospholipid antibody syndrome with aCL antibodies (P = < 0.05).

Infection-related morbidity in systemic lupus erythematosus: a clinico-epidemiological study from northern India

The present study was undertaken to retrospectively evaluate the frequency and pattern of infections in 309 patients with systemic lupus erythematosus (SLE) attending the Rheumatology Clinic of the All India Institute of Medical Sciences Hospital between January 1989 and May 1994. Eighty-two patients (26.5%) were found to be suffering from one or more infections during this period. Tuberculosis was the commonest infection observed. Seventy-four patient (23.9%) had a single infection, while 8 (2.6%) had multiple infections. The infection rate was found to be higher among patients with SLE and major organ involvement than among those with mild superficial SLE.

SLE in Indian men: analysis of the clinical and laboratory features with a review of the literature

Data on the clinical and laboratory profile of 39 male lupus patients has been analysed. An attempt has been made to (1) delineate the pattern of SLE in Indian males, (2) compare it with that reported in the world literature, (3) find out differences, if any, between male children and adults with the disease, and (4) compare it with our previously published data on Indian females with SLE. Several important points were brought out in this study. First, SLE in Indian males has an earlier age of disease onset, a higher incidence of mucocutaneous and renal involvement and a lower incidence of neuropsychiatric, gastrointestinal and hematological disease in comparison to those published from the developed countries. Second, leucopenia and lymphopenia, a reflection of disease severity, occur significantly more in male children compared with adults. Thrombocytopenia is exclusively noted in adult males and virtually non-existent in children. Third, male patients overall have a less severe form of the disease in comparison with their female counterpart, as was evident by significantly less patients with hypocomplementemia, diffuse proliferative lupus nephritis and psychosis. Finally, a higher frequency of infection, particularly tuberculosis, was seen in male patients, which was the cause of death in some.

Prevalence of rheumatoid arthritis in the adult Indian population

The prevalence of rheumatoid arthritis was studied in the adult Indian population. As the first step, a house-to-house survey of a rural population near Delhi was conducted by two trained health workers. The target population comprised 44,551 adults (over 16 years old). The health workers identified the possible cases of rheumatoid arthritis (RA) using a questionnaire. These cases were then further evaluated by the authors using the 1987 revised ARA criteria for the diagnosis of RA. A response rate of 89.5% was obtained and 3393 persons were listed as possible cases of RA by the health workers. Of these, 299 satisfied the revised ARA criteria for the diagnosis of RA, giving a prevalence of 0.75%. Projected to the whole population, this would give a total of about seven million patients in India. The prevalence of RA in India is quite similar to that reported from the developed countries. It is higher than that reported from China, Indonesia, Philippines and rural Africa. These findings are in keeping with the fact that the north Indian population is genetically closer to the Caucasians than to other ethnic groups.

Major histocompatibility complex genes and susceptibility to systemic lupus erythematosus in northern India

Fifty-eight patients with systemic lupus erythematosus (SLE) from Northern India were tissue typed for HLA class I and II antigens. The results revealed an appreciable increase of HLA-DR4 (37.5%) among patients compared with controls (17.9%), P < 0.03. Additionally, haplotype B8-DR3 was encountered frequently in the patient group. The findings suggest an important role of MHC genes in influencing susceptibility to SLE.

Analysis of clinical and laboratory profile in Indian childhood systemic lupus erythematosus and its comparison with SLE in adults

Data on the clinical and laboratory profiles of 83 children with SLE have been analysed and compared with data on 187 adults with the disease. The clinical features of childhood SLE are similar to those seen in adults, although clinical and laboratory parameters reflect propensity to a more severe form of the disease in the juvenile age group. However, in comparison to descriptions of childhood lupus from developed countries, in India the female-to-male ratio in this age group parallels that in adults. Renal involvement is noted to be more common, whereas gastro-intestinal and haematological abnormalities are less common. Interestingly, leucopenia, lymphopenia and nephritic type of renal involvement are commonly seen in boys with SLE, but these features are non-existent in men.

Prevalence of systemic lupus erythematosus in India

Prevalence of systemic lupus erythematosus (SLE) was studied in the northern Indian population by means of a two-pronged approach: (a) antinuclear antibody (ANA) screening of the general population by a new well-standardized finger-prick 'filter paper' technique (sensitivity and specificity: 95.4% and 86.2%, respectively); and (b) a questionnaire survey carried out primarily by trained personnel in the community (sensitivity and specificity: 100% and 68.6% respectively). The low specificity of the two methods was improved by the introduction of a step of secondary screening by the authors, thus excluding false positives. ANA screening of 52,062 individuals yielded 13 positive results, of which only two were found to be true cases of SLE after secondary screening. Questionnaire survey of 39,826 individuals similarly yielded 3393 positive results. On secondary screening, only one of these persons was found to be a case of SLE. Thus, three cases of SLE were detected in a population survey of 91,888, giving a point prevalence of 3.2 per 100,000 (95% CI = 0-6.86 per 100,000). The reported prevalence of SLE ranges from 14 to 60 per 100,000. Thus, the prevalence of SLE in India is comparatively low. Although the reasons for low prevalence are not clear, the study used highly sensitive methodology and it is therefore unlikely that SLE cases were missed. It is hypothesized that SLE is a disease of modernization and therefore its prevalence in a predominantly rural population like that of India is low.

Survival in patients with systemic lupus erythematosus in India

Survival in patients with systemic lupus erythematosus (SLE) in developed countries has improved considerably over the last 2 decades. In India, however, survival in patients with SLE reported 5 years ago from this tertiary referral centre was very poor. The present study was conducted to examine trends, if any, towards improvement in the survival of patients with SLE attending the same centre during the period 1981-1990. No statistically significant change in survival was noted. It appears that improvement in the survival of SLE patients would require an overall improvement in the standard of medical care in India.

High prevalence of systemic disease and mortality in Asian subjects with systemic lupus erythematosus

All patients with systemic lupus erythematosus (SLE) (American Rheumatism Association criteria with positive antinuclear antibody titre) and who attended any of the three general hospitals in Leicester over a 10 year period were ascertained using several complementary sources. Eighty seven subjects (26 Asian, 61 white) were identified. The estimated prevalence of SLE in Leicester is 0.4/1000 for Asian and 0.2/1000 for white subjects. Mean age of onset of the disease was 24 years in Asian and 31 years in white subjects, with both groups showing a female preponderance. Proteinuria (greater than 1 g/24 h) was noted in 15 (58%) Asian and 21 (35%) white subjects; neuropsychiatric disease in 10 (38%) Asian and 8 (13%) white subjects; myalgic symptoms with raised muscle enzymes in 9 (35%) Asian and 3 (5%) white subjects. Nineteen (73%) Asian subjects were positive for extractable nuclear antigens as well, at some stage of their disease, compared with 6 (10%) white subjects. Immunosuppressive treatment was required in 12 (46%) Asian and 12 (20%) white subjects, and deaths of seven Asian and five white subjects were attributed to SLE. These findings show that Asian subjects have a higher prevalence of SLE with greater systemic disease and mortality.

Specificity of anti-Sm antibodies by ELISA for systemic lupus erythematosus: increased sensitivity of detection using purified peptide antigens

Sm antigen was purified by immunoaffinity chromatography using a murine monoclonal anti-Sm antibody and was confirmed to be free from contaminating polypeptides. This was then used to detect anti-Sm antibodies in patients' sera by enzyme linked immunosorbent assay (ELISA). Antibodies against Sm were detected in only 9/52 (17%) patients with systemic lupus erythematosus (SLE) by immunodiffusion, but 15/52 (29%) were positive for IgG anti-Sm antibodies by ELISA. The presence of anti-Sm antibodies remained disease specific despite the increase in sensitivity of this assay and validates its potential use for clinical application. There was no correlation between the presence of anti-Sm antibodies and any clinical features of SLE. In 23 renal biopsies a membranous component to the glomerulonephritis correlated with anti-Sm antibodies (p less than 0.05). Patients from West Africa, the Carribean Islands, and Asia had a higher prevalence of anti-Sm antibodies than the local Caucasian population.