In this descriptive study we have seen that among those who died in the period 2009 – 2011, four out of five had been admitted to and/or had an outpatient consultation in a somatic hospital during their last year of life. The proportion who had been in contact with a psychiatric institution was much lower.
The proportion of deceased persons who had been in contact with a somatic hospital was relatively low among boys/men aged 10 – 29 years. This can most likely be explained by a higher proportion of deaths from violent causes in these age groups.
We found that approximately one in two persons whose underlying cause of death was dementia and Alzheimer’s disease had been admitted and/or had an outpatient consultation during their final year of life, with a very small proportion of deaths in somatic hospitals. This concurs with information from the Cause of Death Registry, showing that the vast majority of persons in this group died in nursing homes (data not shown).
Among persons with unknown or unspecified causes of death, more than half had been in contact with a somatic hospital during their last year of life. However, most of these were registered with outpatient consultations only, which may limit the potential benefits of retrieving data from somatic hospitals to supplement the death certificate in such cases.
For cancers as the underlying cause of death, a relatively large proportion had equivalent diagnostic codes in the Norwegian Patient Register. Since 2010, data from the Norwegian Patient Register have been routinely transferred to the Cancer Registry of Norway (9). The Cancer Registry checks the diagnostic codes in their databases against the Norwegian Patient Register and requests supplementary information from the hospitals if the codes fail to match. Before the decision to introduce routine data transfer, a study was undertaken in which the data on cancer diagnostic codes in the Norwegian Patient Register were collated with data in the Cancer Registry of Norway (10). For all groups of cancers studied, there was good correspondence between the two registries. For some forms of cancer, however, the question will remain as to whether someone has died from or with the cancer. This applies in particular to deaths among elderly men with prostate cancer (11).
In Sweden it has been shown that inclusion of data from patient records for the last year of life to determine the underlying cause of death resulted in a change for approximately 11 % of all deaths, but only for somewhat less than 5 % of deaths from cancer (12). Another Swedish study based on a review of medical histories for the last hospitalisation before death also showed that the quality of data on causes of death varies considerably with the group of causes, with the best correspondence for cancers (13). Similar findings have been made in France, where cancer could most frequently be identified as the last main diagnosis for persons who had died in hospital (14).
To the best of our knowledge, no equivalent studies of contact with mental healthcare institutions during the last year of life have been made, in Norway or internationally. In our study, we found that among those who had died from violent causes, one in five had been in contact with a psychiatric institution during their final year of life. Among the deceased whose underlying cause of death was mental disorder, the corresponding figure was one in twelve. Even though the total number of persons who died from these causes is low, it might be valuable to collect supplementary information from psychiatric institutions for quality assurance of the causes of death reported to the Cause of Death Registry.