Abstract
OBJECTIVES: The aim is to (i) examine the evolution of (multi-)morbidity in Czechia, (ii) analyse changes in mortality by (multi-)morbidity between 2014 and 2023 and (iii) analyse factors driving mortality change in these subpopulations, using national health registry data, which is unique among countries of the former Eastern Bloc. DESIGN: Cross-sectional population-wide analysis. SETTING: Czechia. PARTICIPANTS: Adult population aged 30 and above (n~7.5 million). OUTCOME MEASURES: 1-year period prevalence proportion by age, age-specific and disease-specific occurrence-exposure mortality rates and their coefficient of variation, contributions of age composition, multimorbidity composition and mortality rates to mortality change. RESULTS: Between 2014 and 2023, the prevalence of no or single diseases remained stable at 55%, while complex multimorbidity patterns (3+ diseases) decreased, especially in the 60+ group (from 20% to 16%). Despite additional diagnoses being associated with elevated mortality, especially for those with diabetes and chronic obstructive pulmonary disease (COPD), mortality risks homogenised across (multi)morbid groups, and overall mortality declined (9 pp in neoplasm and COPD, 7 pp in cerebrovascular diseases and 3 pp in diabetes). This decline was primarily due to shifts in multimorbidity composition; without this, mortality in groups with cerebrovascular diseases, diabetes and COPD would have risen. CONCLUSION: The change in mortality over the past decade in Czechia among people with chronic diseases is mainly driven by shifts in multimorbidity composition, rather than pure effects of decline in mortality, contributing to diverging patterns of change between individuals with and without chronic conditions.