hospitalised with hip fracture: A POPULATION-BASED MATCHED COHORT - - PowerPoint PPT Presentation

A POPULATION-BASED MATCHED COHORT STUDY

Mortality risk among adults hospitalised with hip fracture:

Reidar P. Lystad1 Cate M. Cameron2 Rebecca J. Mitchell1

1 Australian Institute of Health Innovation,

Macquarie University

2 Menzies Health Institute Queensland,

Griffith University

Background

• Hip fracture is a major public health problem
• Hip fracture is a very common cause of death

in older people

• Many factors have been associated with a

higher risk of mortality, e.g.

• Sex (males)
• Age (older age groups)
• Socioeconomic status (lower)
• Comorbid or pre-existing health conditions

(e.g. CVD, diabetes, mental health)

Commonwealth of Australia, 2010

Ageing population

Aim

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To quantify and describe mortality attributable to hip fracture during the 12 months following a hip fracture-related hospitalisation, among individuals aged ≥65 years in Australia

Methods

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• Population-based matched cohort study using linked

emergency department presentation, hospital admission, and mortality records

• Hip fracture cohort:
• Individuals aged ≥65 years
• Hospitalised with hip fracture in 2009
• NSW, QLD, SA, TAS
• Comparison cohort randomly selected from the electoral

roll, matched 1:1 on age, sex, and residential postcode STUDY POPULATION & DATA SOURCES

Methods

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12-month look-back period Selection period 12-month follow-up period Comorbid conditions Mental health diagnoses Alcohol misuse and dependence Cumulative hospital length of stay Mortality 2009 2008 2010

Methods

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OUTCOME MEASURES 12-month survival Unadjusted and adjusted mortality rate ratios Attributable risk percentage Mortality rate by month post injury Kaplan-Meier plot with log-rank test Cox proportional hazard regression

𝑩𝑺% = 𝟐𝟏𝟏 × 𝒃𝒆𝒌 𝑵𝑺𝑺 − 𝟐 𝒃𝒆𝒌 𝑵𝑺𝑺

Time series plot

Results

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COHORT CHARACTERISTICS

Characteristic Hip fracture cohort (n=9,748) Non-injured cohort (n=9,748) Australian state n % n % New South Wales 5,309 56.0 5,309 56.0 Queensland 2,828 29.8 2,828 29.8 South Australia 1,080 10.7 1,080 10.7 Tasmania 323 3.4 323 3.4 Sex Male 2,667 28.1 2,667 28.1 Female 6,811 71.9 6,811 71.9 Age group 65–74 years 1,218 12.9 1,218 12.9 75–84 years 3,570 37.7 3,570 37.7 ≥85 years 4,690 49.5 4,690 49.5 Location of residence Urban 6,259 66.0 6,259 66.0 Rural 3,219 34.0 3,219 34.0 Charlson comorbidity conditions 4,775 50.4 8,148 86.0 1-2 3,843 40.6 1,240 13.1 ≥3 860 9.1 90 1.0 Other health conditions Mental health diagnoses 380 4.0 105 1.1 Alcohol misuse and dependence 194 2.1 30 0.3

Results

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12-MONTH SURVIVAL

Results

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UNADJUSTED MORTALITY RATE RATIOS

Results

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ADJUSTED MORTALITY RATE RATIOS

Results

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ATTRIBUTALBE RISK %

Results

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MONTHLY MORTALITY RATE

Discussion

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• What accounts for the excess mortality among older

people who experience hip fracture?

• What accounts for the disparity between sexes?
• What accounts for the disparity between age groups?
• What are the implications of these findings?
• What are the limitations of this study?

Summary

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Lystad RP, Cameron CM, Mitchell RJ. Mortality risk among older Australians hospitalised with hip fracture: a population-based matched cohort study. Arch Osteoporosis 2017;12:67.

• Societal burden of hip fracture is projected to

increase in coming decades

• Older people who experience hip fracture are

3.5 times more likely to die within 12 months

• 72% of excess mortality can be attributed to

the hip fracture itself

• Prevention is key to reduce hip fracture-related

mortality

Acknowledgements

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Tasmanian Data Linkage Unit Statistical Services Branch, QLD Health

Thank you for your attention…