Changes in falls and fracture rates in New Zealand elderly : retrospective analysis

Abstract

BACKGROUND: Falls are highly prevalent in elderly people and are responsible for health challenges and injury, ranging in severity and type. Many factors, including changes in public policy or behaviour, might influence fall and fracture rates in older populations. Data available from Accident Compensation Corporation (ACC) of New Zealand could be used to observe trends in fall and fracture rates and evaluated in relation to any known changes in these factors. A longitudinal examination of falls and fracture incidence in older individuals might thereby further guide the planning of health services in New Zealand.

OBJECTIVES: Determine, using New Zealand-wide and regionally-specific ACC data, whether or not there are any demographic changes in numbers of falls or fall-related fracture claims or rates, adjusted for population or for total number of claims, by gender, ethnicity (Māori versus non-Māori), or 5-year age groups over 65 years. Additionally, to assess agreement rates of ACC falls coding and falls identified from a sample of available accident descriptions.

METHODS: The number of ACC claims relating to falls and fall-related fractures in persons aged 65 years and over for National and Bay of Plenty (BOP) and Lakes District specific populations were determined for the period 1997 – 2013. Age group, ethnicity and temporal trends in numbers and rates of claims were plotted. The poor quality of accessible data for years preceding 2007 restricted analysis. Outcomes were established for each ethnicity x gender x age-group category from 2007 – 2013.

RESULTS: Population corrected results showed very little change in fall and fall-related fracture rates during the investigated period in most age groups. The most prominent changes occurred in those aged >80 years. Reductions of 11% and 25% in those aged over 80 years, compared to under, were demonstrated for fall-related fractures for both National and regional populations respectively. In those over 80 years, temporal changes between 2007 – 2013, in both fall and fall-related fracture rates were greatest when adjusted for both population and total number of claims, with a 37% decrease in falls and 71% decrease in fall-related fracture observed. Overall, temporal decreases were shown to be most prominent for Māori individuals. Non-Māori consistently experienced greater fall (74% and 78% higher in National and regional populations) and fall-related fracture (82% and 56%) claim rates compared to Māori when adjusted for population only.

CONCLUSIONS: Based on minimal changes seen in ACC claim rates since 2007, recent interventions or changes in the use of vitamin D may have had relatively little influence on falls and fall-related fractures. Slight temporal reductions in fracture rates in the advanced elderly (80 years and over) may have occurred as the result of improvements in bone strength during the investigated period. Non-Māori, compared to Māori, individuals appear to have a greater risk of falling and sustaining a fracture from falling. Limitations associated with historical and present ACC claim data include missing accident descriptions, unidentified falls, and errors and inconsistencies in falls coding. Research of a similar nature in the future should make use of the increasingly robust ACC data set over a longer period.