Prevalence of multiple long‐term conditions with psoriasis in England: A cohort study using the Clinical Practice Research Datalink

Abstract Background People with psoriasis live with other long‐term conditions (co‐morbidities) that affect their use of healthcare, but the scale of this is not well characterised. Objectives Estimate the concurrent prevalence of co‐morbidities known to affect the use of healthcare in people living with psoriasis in England. Methods A retrospective cohort study using linked data from the UK's Clinical Practice Research Datalink with Hospital Episode Statistics, Office for National Statistics mortality records, and Index of Multiple Deprivation 2010. A cohort of adults (≥18 years) with psoriasis was matched with a comparator cohort of individuals based on age, sex and registered general practice between April 2007 and December 2017. A predefined list of 21 co‐morbidities was selected from a published measure: the Cambridge Multimorbidity Index (CMI). Descriptive analysis describes prevalence with statistical tests (t tests; two‐sample proportions test) of difference for selected variables. Results The study cohort comprised 372,949 individuals (54,817 psoriasis; and 318,132 matched‐comparator). The calculated CMI general score was statistically higher at 0.54 (standard deviation: 0.9) for psoriasis compared with 0.39 (standard deviation: 0.75) for the matched comparator (t test; p < 0.001). A higher percentage (53.2%) of individuals within the psoriasis cohort had at least one co‐morbidity compared with 45.4% of individuals in the matched‐comparator cohort. The prevalence of 20 individual co‐morbidities was statistically significantly (two‐sample proportions test; p < 0.001) higher than in the matched‐comparator cohort. Conclusions Individuals living with psoriasis are more likely to live with multiple long‐term conditions that have developed at an earlier age compared with those without psoriasis. Knowing the characteristics for a higher prevalence of co‐morbidities in people living with psoriasis provides clinicians with the motivation to consider more holistic approaches to improve management and treatment, noting the importance of mental health alongside physical health, and enabling a conversation about the importance of making lifestyle changes.