P300 Comparison of birth rates, gestational diabetes and non-standard maternal deliveries between Takayasu arteritis patients and the England and Wales population

Abstract

Abstract Background/Aims Takayasu arteritis (TAK) is a chronic, inflammatory vasculitis of the aorta and primary branches, particularly prevalent in women of childbearing age. We studied pregnancy outcomes for women with TAK compared to the general population. Methods All people in England with an ICD-10 diagnostic code for TAK 1997/98 to 2020/21 were identified from Hospital Episode Statistics (HES) using National Congenital Abnormality and Rare Disease Registration Service (NCARDRS) data (CAG 10-02(d)/2015). To improve precision of estimated date of diagnosis, we used an English hospital case register of 122 TAK patients. We analysed all HES admissions occurring after their clinician-confirmed diagnosis date and before their first TAK ICD code in HES to identify codes which indicated likely TAK-related activity, and then applied these to the whole NCARDRS cohort. Maternity-related ICD-10 and OPCS-4 code admissions after the estimated diagnosis date were extracted and age-specific values were calculated for number of births, TAK patient years and birth rates. ONS published national data was used for comparison. Results We identified 1,437 people with TAK. Between 2001 and 2021, there were 133 babies born (129 singleton, 2 twin births, no stillbirths) to 85 mothers. Mean maternal age at first delivery was 32.2 years (SD 5.3, median 33.2), above the UK mean of 27.8, with age-specific birth rates compared to the 2019 general population (see table). Overall birth rate in women with TAK was 68% of the national England/Wales rate. Gestational diabetes (GDM) was present in 13/131 (9.9%) but large variation in UK prevalence estimates makes national comparison difficult. Mothers with GDM had a median age of 37 and delivery was by C-section in 9/13 cases. For non-GDM, 50% (95% CI: 41%, 59%) were C-section; this is significantly higher than the UK level of 26%. 12% were vacuum and/or forceps assisted deliveries, approximately equal to the general population. Conclusion The birth rate in women with TAK is lower than the general population and C-section rates higher. Causes are complex and might include patient choice, reduced fertility related to cytotoxic treatment, or physician recommendation, highlighting the importance of equitable access to specialist pre-conception counselling for people with rare autoimmune diseases. Disclosure D.J. Groves: None. M. Rutter: None. P.C. Lanyon: None. M. Odingo: None. M.J. Grainge: None. M. Bythell: None. J. Aston: None. S. Stevens: None. J.R. Hannah: None. J. Mason: None. F.A. Pearce: None.