Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2018 Feb 14;8(2):e018969.
doi: 10.1136/bmjopen-2017-018969.

Mortality and quality of death certification in a cohort of patients with Parkinson's disease and matched controls in North Wales, UK at 18 years: a community-based cohort study

Affiliations

Mortality and quality of death certification in a cohort of patients with Parkinson's disease and matched controls in North Wales, UK at 18 years: a community-based cohort study

Peter Hobson et al. BMJ Open. .

Abstract

Objective: This investigation reports the cause and the quality of death certification in a community cohort of patients with Parkinson's disease (PD) and controls at 18 years.

Setting: Denbighshire North Wales, UK.

Participants: The community-based cohorts consisted of 166 patients with PD and 102 matched controls.

Primary outcomes: All-cause mortality was ascertained at 18 years by review of hospitals' primary care records and examination of death certificates obtained from the UK General Register Office. Mortality HRs were estimated using Cox proportional regression, controlling for covariates including age at study entry, age at death, gender, motor function, mood, health-related quality of life (HRQoL) and cognitive function.

Results: After 18 years, 158 (95%) of patients in the PD cohort and 34 (33%) in the control cohort had died. Compared with the general UK population, the PD cohort had a higher risk of mortality (standard mortality rate, 1.82, 95% CI 1.55 to 2.13). As the primary or underlying cause of death, PD was not reported in 75/158 (47%) of the death certificates. In addition, although 144/158 (91%) of the PD cohort had a diagnosis of dementia, this was reported in less than 10% of death certificates. The main cause of death reported in the PD cohort was pneumonia (53%), followed by cardiac-related deaths (21%). Compared with controls, patients with PD had a greater risk of pneumonia (2.03, 95% CI 1.34 to 3.6), poorer HRQoL and more likely to reside in institutional care at death (P<0.01).

Conclusion: This investigation found that PD was associated with an excess risk of mortality compared with the general population. However, PD as a primary or underlying cause of death recorded on certificates was found to be suboptimal. This suggests that the quality of mortality statistics drawn from death certificates alone is not a valid or reliable source of data.

Keywords: death certification; dementia; mortality; parkinson’s disease.

PubMed Disclaimer

Conflict of interest statement

Competing interests: None declared.

Figures

Figure 1
Figure 1
Kaplan-Meier survival curves for all-cause mortality in the Parkinson’s disease (PD) and control cohorts.

References

    1. Devis T, Rooney C. Death certification and the epidemiologist. Health Statistics Quarterly 1999;1:21–33.
    1. Hanzlick R. Cause of death and the death certificate: Important information for physicians, coroners, medical examiners, and the public. Northfield, IL: College of American Pathologists, 2006.
    1. World Health Organisation. International classification of diseases and related health problems. Tenth Revision Geneva: WHO, 1992.
    1. Rooney C, Smith S. Implementation of ICD-10 for mortality data in England and Wales from January 2001. Health Statistics Quarterly;2000:41–50.
    1. Rooney C, Griffiths C, Cook L. Implementation of ICD-10 for cause of death coding – some preliminary results from the bridge coding stud. Health Statistics Quarterly 2002;13:31–41.

MeSH terms