Multimorbidity is highly prevalent and increasing among patients with atrial fibrillation, with 85% of 196,536 individuals with new-onset AF having diagnoses from ≥2 comorbidity groups, highlighting the importance of a holistic management approach.
Key Findings
Results
The vast majority of patients with new-onset atrial fibrillation had multimorbidity at the time of diagnosis.
85% of 196,536 individuals with new-onset AF had diagnoses from ≥2 comorbidity groups
28% of patients had diagnoses from ≥6 comorbidity groups
Data were drawn from the nationwide Finnish FinACAF cohort study covering all patients with incident AF between 2009 and 2018
Comorbidity data were obtained using a fixed 5-year look-back period from national healthcare, reimbursement and prescription registers
Results
The mean number of distinct comorbidity groups among AF patients increased over the study period from 2009 to 2018.
Mean number of different comorbidity groups increased from 3.9 to 4.2 between 2009 and 2018
The increase in multimorbidity over time remained statistically significant after adjustment for age and sex
Adjustment for age attenuated but did not eliminate the association between calendar time and multimorbidity
Results
Multimorbidity burden was higher in women than in men among patients with new-onset AF.
Mean number of distinct comorbidity groups was 4.2 in women versus 3.9 in men
Multimorbidity also increased with advancing age across the cohort
Results
The most prevalent comorbidity categories among AF patients were hypertensive diseases, obesity and other metabolic diseases, diabetes, and other cardiovascular diseases.
These four comorbidity groups were identified as the most common at the time of new-onset AF
A previously established comorbidity categorisation was applied to characterise multimorbidity burden
Comorbidity groups were derived from national healthcare and prescription register data
Results
The prevalence of certain cardiovascular comorbidities declined during the study period.
The prevalence of ischaemic heart disease declined between 2009 and 2018
The prevalence of other diseases of the heart and pulmonary circulation also declined over the study period
These declining trends occurred in the context of overall increasing multimorbidity burden
What This Means
This research used nationwide Finnish health registry data to examine how many different health conditions patients had when they were first diagnosed with atrial fibrillation (AF), an irregular heart rhythm condition, and whether this changed over time from 2009 to 2018. The study included nearly 200,000 people and found that having multiple health conditions at the same time (called multimorbidity) was extremely common: 85% of AF patients had at least two different categories of health problems, and more than a quarter had six or more. The average number of comorbidity groups per patient grew from 3.9 to 4.2 over the decade studied, even after accounting for the aging of the population.
The most common additional health conditions found alongside AF were high blood pressure, obesity and metabolic disorders, diabetes, and other cardiovascular diseases. Women with AF tended to have more comorbidities than men, and older patients had more than younger ones. Interestingly, while overall multimorbidity increased, the rates of ischaemic heart disease (narrowed coronary arteries) and some other heart conditions actually decreased during the study period, possibly reflecting improvements in prevention and treatment of those specific conditions.
This research suggests that AF rarely occurs in isolation — the overwhelming majority of patients also have other significant health conditions that need to be managed simultaneously. The finding that multimorbidity is both very common and growing in this population underscores the need for healthcare approaches that consider all of a patient's conditions together rather than treating each one separately. This has practical implications for how healthcare systems organize care for AF patients and for clinical guidelines, which traditionally focus on single diseases.
Reinilä S, Kiuru N, Langén V, Jaakkola J, Halminen O, Putaala J, et al.. (2026). Temporal Trends in Multimorbidity Patterns in Patients With Atrial Fibrillation-A Nationwide Cohort Study.. European journal of clinical investigation. https://doi.org/10.1111/eci.70253