This study aimed to characterise how prevalence estimates of single and multiple organ fibrosis changed between 2012 and 2022 in an adult population in England.
A retrospective population-based cohort design was used. The analysis drew on linked electronic health records from primary care (Clinical Practice Research Datalink Aurum) and secondary care (Hospital Episode Statistics Admitted Patient Care). These data sources were used to identify diagnoses recorded in routine clinical care across the study period.
The study population comprised adults aged 18 years and older whose primary and secondary care records were available for research. Case identification for fibrotic conditions was based on diagnoses determined from a clinician Delphi survey; these diagnostic codes were sought in either primary or secondary care records. The cohort included 5,839,459 people with at least one fibrotic condition and used a denominator of 18,784,962 adults for prevalence calculations.
The primary analysis estimated annual prevalence of single and multiple organ fibrosis across the decade. A secondary analysis used Cox proportional hazards models to evaluate the association between the time-updated number of fibrotic conditions and risk of death, with adjustment for age and sex.
Over the study period, the overall prevalence of fibrotic conditions increased by 6.72%. By 2022, 19.95% (95% CI 19.92% to 19.98%) of adults had at least one fibrotic condition. The prevalence of multiple organ fibrosis rose from 4.78% (95% CI 4.76% to 4.79%) in 2012 to 8.51% (95% CI 8.50% to 8.53%) in 2022.
Health-care use in the year preceding diagnosis differed between groups. The median number of primary care consultations in the year before diagnosis was 14 for people who went on to have a single organ fibrotic diagnosis, compared with a median of 21 consultations for those with multiple organ fibrosis.
Cox proportional hazards models with the number of fibrotic conditions treated as a time-updated exposure and adjusted for age and sex showed stepwise increases in mortality risk with greater fibrotic multimorbidity. Compared with people with a single organ fibrotic condition, people with two fibrotic conditions had a mortality hazard ratio (HR) of 2.90 (95% CI 2.87 to 2.93). People with three fibrotic conditions had a mortality HR of 5.22 (95% CI 5.14 to 5.30).
The authors estimate that multiple organ fibrosis affects more than 3 million people in the UK and that this burden is increasing. People with multiple organ fibrosis accessed primary care more often in the year before diagnosis than those with single organ fibrosis, and they faced substantially higher mortality risk. These findings suggest that patterns of fibrotic multimorbidity represent an important and growing public health concern and that earlier recognition of multimorbidity could present opportunities to reduce mortality.
Between 2012 and 2022, the prevalence of both single and multiple organ fibrosis increased substantially in this large England-based cohort. Multiple organ involvement was associated with greater primary care use prior to diagnosis and markedly higher adjusted mortality. Better understanding of fibrotic multimorbidity patterns may help inform earlier diagnosis and interventions aimed at reducing mortality.
The study defined fibrotic conditions using codes identified via a clinician Delphi survey and ascertained diagnoses from primary or secondary care records. The mortality analyses adjusted for age and sex and used time-updated counts of fibrotic conditions. Other methodological details beyond those described in the source were not reported in the provided text.