Population

Patients registered in SwedeHF

All patients recorded in SwedeHF are included. This cohort includes patients up until 2023-12-31.

Patients with HF from the National Patient Register

Patients with an ICD-10 code for HF in main position in the National Patient Register (ICD-10: I110, I130, I132, I255, I420, I423, 1425-9, I43, I50, J81, K761) starting from 2000-01-01 with no previous ICD-9/10 code for HF (I110 I130 I132 I255 I420 I423 1425 I426 I427 I428 I429 I43 I50 J81 K761 ICD-9: 414W 425E 425F 425G 425H 425W 425X 428) since 1987. This cohort includes patients up until 2021-12-31.

HF-free controls

For each post in SwedeHF or the first date in the National Patient Register a set of controls was chosen by Statistics Sweden in a ratio of 2:1. Since a person can have more than one registered post in SwedeHF a patient can have more than 2 controls in total, up to 2 for each posts. This cohort includes patients up until 2021-12-31.

Eligible controls were persons without re-used Swedish personal identity numbers (PINs) and free of HF, defined either in the National Patient registry (ICD-10: I110, I130, I132, I255, I420, I423, 1425-9, I43, I50, J81, K761, R570, ICD-9: 414W, 425E-H, 425W, 425X, 428) or SwedeHF, at the end of the year of the index date for the case and matched by gender, year of birth and county of residence at index. For posts with age ≥ 90 years, controls were only matched by gender and year of birth due to the smaller available number of controls.

The selection of controls was performed without replacement.

A control was allowed to become a case after the year of the index date for the case.

A full set of controls (n = 2) was not found for all cases:

Population No controls Posts Unique patients
Case SwedeHF 0 40426 19069
Case SwedeHF 1 17211 7319
Case SwedeHF 2 185576 104908
Case NPR 0 19187 19187
Case NPR 1 26442 26442
Case NPR 2 377463 377463

Inclusion/exclusion criteria

Criteria Case SwedeHF Case NPR Control SwedeHF Control NPR
No of posts recieved 246769 494514 405907 803243
Exclude posts with duplicated index dates 246146
Exclude posts with with index date < 2000-01-01 246143 459841 405901 800473
Exclude posts with with index date > 2023-12-31 (SwedeHF)/2021-12-31 (NPR HF, Controls) 243917 426264 388934 785670
Exclude posts < 18 years 243900 424979 388907 783134
Exclude posts that are not present in SCB register 243489 423627 388907 783134
Exclude posts with reused PINs 243224 423251 388907 783134
Exclude posts censored end fu < index 243213 423092 388841 782402
Exclude controls without cases 243213 423092 388841 782402
Exclude posts with end of follow-up <= index date (died in hospital) 239931
Unique patients 129273