Cervical and breast cancer screening uptake among women with serious mental illness: a data linkage study

Background: Breast and cancer screening uptake has been found to be lower among women with serious mental illness (SMI). This study aims to corroborate these findings in the UK and to identify variation in screening uptake by illness/treatment factors, and primary care consultation frequency.

Methods: Linked population-based primary and secondary care data from the London borough of Lambeth (UK) were used to compare breast and cervical screening receipt among linked eligible SMI patients (n = 625 and n = 1393), to those without SMI known only to primary care (n = 106,554 and n = 25,385) using logistic regression models adjusted first for socio-demographic factors and second, additionally for primary care consultation frequency.

Results: Eligible SMI patients were less likely to have received breast (adjusted odds ratio (OR) 0.69, 95 % confidence interval (CI), 0.57 - 0.84, p < 0.001) or cervical screening (adjusted OR 0.72, CI: 0.60 - 0.85, p < 0.001). Schizophrenia diagnosis, depot injectable antipsychotic prescription, and illness severity and risk were associated with the lowest odds of uptake of breast (adjusted ORs 0.46 to 0.59, all p < 0.001) and cervical screening (adjusted ORs 0.48 - 0.65, all p < 0.001). Adjustments for consultation frequency further reduced effect sizes for all subgroups of SMI patient, in particular for cervical screening.

Conclusions: Women with SMI are less likely to receive breast and cervical cancer screening than comparable women without SMI. Higher primary care consultation rates among SMI patients is likely a mediating factor between SMI status and uptake, particularly for cervical screening - a service organised in primary care. To tackle health disparities linked to SMI, efforts at increasing screening uptake are key and should be targeted at women with other markers of illness severity or risk, beyond SMI status alone.