Global and regional prevalence and incidence of systemic lupus erythematosus in low-and-middle income countries: a systematic review and meta-analysis

Systemic lupus erythematosus (SLE) may be more prevalent among most ethnic groups in the low-and-middle income countries (LMICs), still these countries are under-represented in epidemiological data on SLE. The aim of this study was to review the prevalence and incidence of SLE in LMICs and use meta-analytic techniques. The MEDLINE, CINHAL, Web of Science, Scopus and Global Index Medicus databases were searched for relevant studies published up to July of 2022. Papers selected for full-text review were included in the systematic review if they provided the prevalence or incidence of SLE in LMICs and published in English language. The reference lists of included articles were also searched for additional studies. Two individuals independently performed abstract and full-text review, data extraction, and quality assessment of the papers. The prevalence and incidence of SLE were pooled through random effects model. Pooled estimates were expressed with 95% confidence. Out of 2340 papers, 23 studies were included in the review. The mean age at diagnosis ranged from 25.5 to 45.8 years. Three studies were conducted in Argentina and Brazil, two studies in China and one study in Cuba, Colombia, Democratic Republic Congo, Ecuador, Egypt, India, Kenya, Malaysia, Mexico, Nigeria, Pakistan, Turkey, Ukraine, Venezuela, and Zimbabwe. The SLE prevalence and incidence varied from 3.2 to 159 per 100,000 and 0.3-8.7 per 100,000 persons, respectively. In a random effects meta-analysis (n = 10), the pooled prevalence of SLE was 103 (95% confidence interval [CI] - 17 to 224) per 100,000. Meta-analysis of data from 6 incidence studies revealed an incidence of 5 cases per year (95% CI 2-8) per 100,000. According to WHO regions, the pooled prevalence of American and Western Pacific regions was 300 (95% CI - 200 to 900) and 36 (95% CI 35-37) per 100,000, respectively. The pooled incidence of the American region was 10 (95%, 0-14) per 100,000 inhabitants. Systemic lupus erythematosus is a common disease with considerable variation in prevalence and incidence among the general population in LMICs. Accurate estimates of prevalence and incidence of SLE are required to put in place appropriate programmes to reduce its burden in LMICs. PROSPERO registration number: CRD: 42020197495, https://www.crd.york.ac.uk/prospero/ .