Explore comorbidities associated with systemic lupus erythematosus: a total population-based case-control study

Examination of the shared genetic architecture between multiple sclerosis and systemic lupus erythematosus facilitates discovery of novel lupus risk loci

Systemic Lupus Erythematosus (SLE) is an autoimmune disease with heterogeneous manifestations, including neurological and psychiatric symptoms. Genetic association studies in SLE have been hampered by insufficient sample size and limited power compared to many other diseases. Multiple Sclerosis (MS) is a chronic relapsing autoimmune disease of the central nervous system (CNS) that also manifests neurological and immunological features. Here, we identify a method of leveraging large-scale genome wide association studies (GWAS) in MS to identify novel genetic risk loci in SLE. Statistical genetic comparison methods including linkage disequilibrium score regression (LDSC) and cross-phenotype association analysis (CPASSOC) to identify genetic overlap in disease pathophysiology, traditional 2-sample and novel PPI-based mendelian randomization to identify causal associations and Bayesian colocalization were applied to association studies conducted in MS to facilitate discovery in the smaller, more limited datasets available for SLE. Pathway analysis using SNP-to-gene mapping identified biological networks composed of molecular pathways with causal implications for CNS disease in SLE specifically, as well as pathways likely causal of both pathologies, providing key insights for therapeutic selection.

High risk of depression, anxiety, and an unfavorable complex comorbidity profile is associated with SLE: a nationwide patient-level study

Objectives

The aim of this national population-based, retrospective database study is to compare the comorbidity profiles of systemic lupus erythematosus (SLE) patients and general population controls matched for age, gender, and region and assess the risk of depression or anxiety when controlled for age, gender and adjusted for the Charlson Comorbidity Index (CCI).

Methods

Claims data of 1051 patients diagnosed with SLE (full population between January 01, 2011, and December 31, 2014) from the Hungarian National Health Insurance Fund have been analyzed against matched controls (1:5 ratio) with a follow-up of 30 months. The first record of SLE diagnosis was considered the diagnosis date. The odds ratio (OR) and 99.9% confidence interval (CI) of having depression or anxiety among patients with SLE vs. controls have been assessed using logistic regression models.

Results

SLE patients report more comorbidities than the matched general population both in pre- and post-index periods (mean CCI 1.79 vs. 1.15 and 2.78 vs. 1.22 [both p<0.001], respectively). Both SLE patients and controls diagnosed with depression or anxiety had significantly higher CCI than those without comorbid depression or anxiety (p<0.001). However, SLE patients had a twofold higher risk of depression or anxiety than matched controls when controlled for age, gender, and adjusted for CCI.

Conclusion

Our analysis indicates the enormity of comorbidity burden in SLE, especially that of anxiety and depression. The size and complexity of the comorbidity burden emphasizes the importance of early diagnosis and intervention with comprehensive modalities incorporating attention to comorbidities in SLE patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02799-6.

Comorbidities of systemic lupus erythematosus prior to and following diagnosis in different age-at-onset groups

OBJECTIVES

Systemic lupus erythematosus (SLE) is a female-dominated autoimmune disease that can occur at any age and has a diverse course. The clinical manifestation of this disease can vary depending on the patient's age at onset. The aim of this study was to characterise the comorbidities at the time of SLE diagnosis and after in different age groups.

METHODS

A total 1042 incident cases of SLE with a Catastrophic Illness Card in 2005 and 10,420 age- and sex-matched controls from the general population registered in the National Health Insurance Research Database in Taiwan were enrolled in the study. The risk of comorbidities before (adjusted odds ratio, [aOR]) and after (adjusted hazard ratio, [aHR]) of SLE was analysed. The burden of these SLE-associated comorbidities was weight by the Charlson comorbidity index (CCI). We used the cumulative incidence to evaluate the impact of comorbidities on different age onset groups.

RESULTS

In this study, musculoskeletal diseases had the highest positive association (aOR, 5.29; 95% confidence interval [CI]: 4.25-6.57) prior to the diagnosis of SLE and they were also the most common developing incident comorbidity after the diagnosis (HR, 13.7; 95% CI: 11.91-15.77). It only took less than 1 year for 50% of the late-onset SLE patients to develop any increase in CCI score. The developing comorbidities attributed to 16.3% all-cause mortality and they had the greatest impact on late-onset SLE patients, with 33.3% cumulative incidence to all-cause mortality. There is no difference in the incidence of infectious diseases across different age groups. The herpes zoster infection had the greatest cumulative incidence among the category of infection diseases in child-onset SLE patients.

CONCLUSION

SLE patients had increased risks of multiple pre-existing comorbidities at diagnosis. The developed comorbidity after diagnosis could contribute to all-cause mortality. The herpes zoster infection is primarily an issue in child-onset SLE patients.