Death certificate data of patients with amyotrophic lateral sclerosis in easternmost Finland

Objective: Topical data on causes of death and death certificate (DC) accuracy in patients with amyotrophic lateral sclerosis (ALS) are constantly needed. Methods: Data on a previously published ALS cohort from North Karelia in easternmost Finland was updated by extracting DC information from the electronic health records. Results: Death certificate data were available for 91% of the deceased. In all cases, ALS had been coded as a cause of death. In four cases, it had been inserted as a contributory cause of death. In three cases, ALS was indicated but incorrect coding was used. Three of the four cases in which ALS had not been deemed the underlying or immediate cause of death were cardiovascular deaths. One or more contributory causes of death had been recorded in 28% of DCs (54% of these were cardiovascular disorders), although comorbidities had not always been coded in the DC. In individual cases, the death had been sudden and unexpected, resembling a cardiovascular death, but this had not been coded. Conclusion: Finnish DC data remain a very reliable data source for ALS epidemiology, albeit with the caveat that data need to be obtained rigorously. Comorbidities are incompletely recorded as may be some immediate causes of death.