Using the BILAG Biologics Prospective Cohort to analyse health care use for Systemic Lupus

Erythematosus (SLE) patients

Zhongjiu Lu, NIHR Research Method InternDr. Brenda GannonProf Ian Bruce

Introduction of Lupus disease

• Systemic lupus erythematosus (SLE), known as lupus, is an autoimmune disease in which the body’s immune system mistakenly attacks healthy tissue in many parts of the body.

• Common symptoms include painful and swollen joints, fever, chest pain, hair loss, feeling tired, and a red rash which is most commonly on the face.

Background• The BILAG Biologics Prospective Cohort is a prospective

observational cohort study of patients with SLE who are starting treatment with a biologic drug or a conventional, non-biologic therapy.

• The study aims to recruit 220 patients into the biologic treatment group and a further 220 patients into the conventional, non-biologic therapy cohort.

• Recruitment began in September 2010 and continued in the first instance until October 2015

Background

• 43 UK-wide centres signed up for observational cohort study

• Monitor “real world” safety and effectiveness of biologic therapies in treatment of SLE, compared to standard, immunosuppressive therapies

• All patients were diagnosed with SLE, aged 5 years or older and provided consent.

Categories of biologic patients

Biologic – starting first biologic therapy (previously biologically naïve)

Biologic - starting repeat of same biologic therapy (e.g. rituximab → rituximab)

Biologic – starting a different, new biologic therapy (e.g. rituximab → belimumab)

Biologic – switched from control patient within the study

Literature review• The employment rate amongst patients varies from 35% to

55% (Zhu, Tam,Li, 2011)

• Cognitive, physical function, and depressive symptoms determine the work loss (Yelin el al, 2009)

• The average direct costs per patient-year ranged from $3,735 to $14,410(Yelin el al, 2009)

• Annual indirect costs per patient ranged from $1,093 to $14,614 (Zhu, Tam,Li, 2011)

Patient data

Baseline

Patient demographics Health status and quality

of life EQ5D SF36 Lupus QoL

Disease activity BILAG 2004 Index SLEDAI2K

SLICC damage index Lifestyle Questionnaire

3 months and 6 months• Disease activity• Adverse events

• Patient QoL• Patient dairies

Data collection

• Data is collected through a web-based data entry system

Baseline 6 months 1 year Annual questionnaires for at least 2 more years3 months

Information collected for at least 3 years

Data process 1

SLEDAI+BILAG• Use "Cleaned SLEDAI" to merge" Cleaned BILAG“

as they both have time point 0 and 2.

SLICC+Lifestyle Questionnaire

• use "Cleaned SLICC" to merge Cleaned Lifestyle Questionnaire as they both have time point 0

SLICC+Lifestyle Questionnaire+SLEDAI+BILAG

• use "SLICC+Lifestyle Questionnaire" to merge "SLEDAI+BILAG"

Data process 2

Used biologic group to append previous

data

Merge Clean_Patients‘diary

Saved as “Analysis data“ ready to

analyse

Data

• Created a panel dataset, consists of baseline information and follow-up outcomes in 3 months and 6 months.

• Used patients diary data as proxies to measure healthcare utilisation for each patient in each period

• Disregarded patients who do not have clinic visit records 456(65%) obs deleted, 245 obs remains(103 unique ID)

Summary statistics tableVariable Obs. Mean/percentage Std. Dev. Min. Max.  

Patients’ ID 245 . . . .

Years of education 220 19.18 4.37 6 42

Age 124 45.34 11.94 20.29 68.13

Clinic visits 127 2.02 1.77 0 12

Time point 245 0.96 0.87 0 2 baseline 97 39.59% . . . 3 months 61 24.90% . . . 6 months 87 35.51% . . .

Gender 245 100% . 0 1 male 22 8.98% . 0 0 female 223 91.02% . 1 1

Treatment group 182 100% 1.99 1 5 Biologic 116 63.74% . . . Standard 58 31.87% . . . Switched to biologic 8 4.40% . . .

Research questions

• What is the impact of treatment on healthcare use?

• How much does SLE cost the patient/health system?

Method

Other potential research questions

• What is the impact of different treatment on patients’ quality of life ?

• How does healthcare use impact on patients’ quality of life ?

Thank you !