Determining risk of hip fracture in older adults with complex needs in New Zealand: A national population time-to-event study

Hip fractures are one of the most common and debilitating injuries in older adults. Older adults who sustain a hip fracture are more likely to have increased mortality and morbidity with reduced quality of life. This, combined with slow recovery times, can lead to a need for entry to aged care facilities. Considerable work has been undertaken to investigate risk factors for hip fracture in the wider clinical research. This study built on that work and aims to identify risk factors for hip fracture in older adults with complex needs in the New Zealand context, based on questions from the interRAI home care (interRAI-HC) assessment. The interRAI-HC assessment is a standardised comprehensive clinical assessment typically given to people aged 65 years and older to assess areas of need that each person has. From the determined risk factors, a hip fracture risk score was developed to identify individuals who are more likely to sustain a hip fracture in the two years following their assessment. Two sets of interRAI-HC data were used in this study. The initial dataset (September 2012 to June 2015) was randomly split into two datasets. Two-thirds of the data was used to explore risk factors for hip fracture and to develop a risk score. A competing risk regression was used to determine which variables were significantly associated with hip fracture and were to be included in the hip fracture risk scores. The remaining one-third of the initial dataset was used to perform cross-validation of the developed scores, evaluating how well the scores predicted hip fracture events not used in the creation of the scores. Separate scores for males and females were created due to their different risk profiles. The predictive power of each score was assessed using Receiver Operator Characteristic (ROC) curves and their associated area under the curve (AUC) at various candidate thresholds. The scores developed were further validated with the second, more recent, set of interRAI-HC assessments (November 2015 to June 2018). Factors associated with hip fracture for the whole interRAI-HC assessment cohort were age, sex, ethnicity, falls, mental function varies, wandering, body mass index (BMI), tobacco use, Parkinson's disease, and dyspnoea (shortness of breath). For males, the risk factors associated with hip fracture were age, Parkinson's disease, and dyspnoea. For females, the factors associated with hip fracture were age, ethnicity, wandering, BMI, tobacco use, and dyspnoea. The male's score had an AUC of 0.586 (95% CI: 0.548 to 0.625), and the female's score had an AUC of 0.615 (95% CI: 0.593 to 0.637). When retesting using the more recent dataset, the male's score had an AUC of 0.611 (95% CI: 0.594 to 0.629) and the female’s score had an AUC of 0.624 (95% CI: 0.612 to 0.636). The scores developed here were modestly predictive of hip fracture risk for a New Zealand interRAI-HC cohort. The results of this thesis provide a good foundation for the development of a more sensitive and specific hip fracture prediction model. With further development, the score could have clinical use for individuals who complete interRAI-HC assessments

Development and validation of a frailty index compatible with three interRAI assessment instruments

BACKGROUND: a Frailty Index (FI) calculated by the accumulation of deficits is often used to quantify the extent of frailty in individuals in specific settings. This study aimed to derive a FI that can be applied across three standardised international Residential Assessment Instrument assessments (interRAI), used at different stages of ageing and the corresponding increase in support needs. METHODS: deficit items common to the interRAI Contact Assessment (CA), Home Care (HC) or Long-Term Care Facilities assessment (LTCF) were identified and recoded to form a cumulative deficit FI. The index was validated using a large dataset of needs assessments of older people in New Zealand against mortality prediction using Kaplan Meier curves and logistic regression models. The index was further validated by comparing its performance with a previously validated index in the HC cohort. RESULTS: the index comprised 15 questions across seven domains. The assessment cohort and their mean frailty (SD) were: 89,506 CA with 0.26 (0.15), 151,270 HC with 0.36 (0.15) and 83,473 LTCF with 0.41 (0.17). The index predicted 1-year mortality for each of the CA, HC and LTCF, cohorts with area under the receiver operating characteristic curves (AUCs) of 0.741 (95% confidence interval, CI: 0.718-0.762), 0.687 (95%CI: 0.684-0.690) and 0.674 (95%CI: 0.670-0.678), respectively. CONCLUSIONS: the results for this multi-instrument FI are congruent with the differences in frailty expected for people in the target settings for these instruments and appropriately associated with mortality at each stage of the journey of progressive ageing.</p

Frailty of Māori, Pasifika, and non-Māori/non-Pasifika older people in New Zealand: a national population study of older people referred for home care services

Little is known about the prevalence of frailty in indigenous populations. We developed a frailty index for older New Zealand Māori and Pasifika who require publicly funded support services.A frailty index (FI) was developed for New Zealand adults aged ≥65 years who had an interRAI-Home Care assessment between 1 June 2012 and 30 October 2015. A frailty score for each participant was calculated by summing the number of deficits recorded and dividing by the total number of possible deficits. This created a FI with a potential range from 0 to 1. Linear regression models for FIs with ethnicity were adjusted for age and sex. Cox proportional hazards models were used to assess the association between the FI and mortality for Māori, Pasifika, and non-Māori/non-Pasifika.Of 54,345 participants, 3,096 (5.7%) identified as Māori, 1,846 (3.4%) were Pasifika, and 49,415 (86.7%) identified as neither Māori nor Pasifika. New Zealand Europeans (48,178, 97.5%) constituted most of the latter group. Within each sex, the mean FIs for Māori and Pasifika were greater than the mean FIs for non-Māori and non-Pasifika, with the difference being more pronounced in females. The FI was associated with mortality (Māori SHR 2.53, 95% CI 1.63 to 3.95; Pasifika SHR 6.03, 95% CI 3.06 to 11.90; non-Māori and non-Pasifika SHR 2.86, 95% 2.53 to 3.25).This study demonstrated differences in FI between the ethnicities in this select cohort. After adjustment for age and sex, increases in FI were associated with increased mortality. This suggests that FI is predictive of poor outcomes in these ethnic groups

Drug burden index and its association with hip fracture among older adults:a national population-based study

Background: The Drug Burden Index (DBI) calculates the total sedative and anticholinergic load of prescribed medications and is associated with functional decline and hip fractures in older adults. However, it is unknown if confounding factors influence the relationship between the DBI and hip fractures. The objective of this study was to evaluate the association between the DBI and hip fractures, after correcting for mortality and multiple potential confounding factors. Methods: A competing-risks regression analysis conducted on a prospectively recruited New Zealand community-dwelling older population who had a standardized (International Resident Assessment Instrument) assessment between September 1, 2012, and October 31, 2015, the study's end date. Outcome measures were survival status and hip fracture, with time-varying DBI exposure derived from 90-day time intervals. The multivariable competing-risks regression model was adjusted for a large number of medical comorbidities and activities of daily living. Results: Among 70,553 adults assessed, 2,249 (3.2%) experienced at least one hip fracture, 20,194 (28.6%) died without experiencing a fracture, and 48,110 (68.2%) survived without a fracture. The mean follow-up time was 14.9 months (range: 1 day, 37.9 months). The overall DBI distribution was highly skewed, with median time-varying DBI exposure ranging from 0.93 (Q = 0.0, Q = 1.84) to 0.96 (Q = 0.0, Q = 1.90). DBI was significantly related to fracture incidence in unadjusted (

Determining risk of hip fracture in older adults with complex needs in New Zealand: A national population time-to-event study

Hip fractures are one of the most common and debilitating injuries in older adults. Older adults who sustain a hip fracture are more likely to have increased mortality and morbidity with reduced quality of life. This, combined with slow recovery times, can lead to a need for entry to aged care facilities. Considerable work has been undertaken to investigate risk factors for hip fracture in the wider clinical research. This study built on that work and aims to identify risk factors for hip fracture in older adults with complex needs in the New Zealand context, based on questions from the interRAI home care (interRAI-HC) assessment. The interRAI-HC assessment is a standardised comprehensive clinical assessment typically given to people aged 65 years and older to assess areas of need that each person has. From the determined risk factors, a hip fracture risk score was developed to identify individuals who are more likely to sustain a hip fracture in the two years following their assessment. Two sets of interRAI-HC data were used in this study. The initial dataset (September 2012 to June 2015) was randomly split into two datasets. Two-thirds of the data was used to explore risk factors for hip fracture and to develop a risk score. A competing risk regression was used to determine which variables were significantly associated with hip fracture and were to be included in the hip fracture risk scores. The remaining one-third of the initial dataset was used to perform cross-validation of the developed scores, evaluating how well the scores predicted hip fracture events not used in the creation of the scores. Separate scores for males and females were created due to their different risk profiles. The predictive power of each score was assessed using Receiver Operator Characteristic (ROC) curves and their associated area under the curve (AUC) at various candidate thresholds. The scores developed were further validated with the second, more recent, set of interRAI-HC assessments (November 2015 to June 2018). Factors associated with hip fracture for the whole interRAI-HC assessment cohort were age, sex, ethnicity, falls, mental function varies, wandering, body mass index (BMI), tobacco use, Parkinson's disease, and dyspnoea (shortness of breath). For males, the risk factors associated with hip fracture were age, Parkinson's disease, and dyspnoea. For females, the factors associated with hip fracture were age, ethnicity, wandering, BMI, tobacco use, and dyspnoea. The male's score had an AUC of 0.586 (95% CI: 0.548 to 0.625), and the female's score had an AUC of 0.615 (95% CI: 0.593 to 0.637). When retesting using the more recent dataset, the male's score had an AUC of 0.611 (95% CI: 0.594 to 0.629) and the female’s score had an AUC of 0.624 (95% CI: 0.612 to 0.636). The scores developed here were modestly predictive of hip fracture risk for a New Zealand interRAI-HC cohort. The results of this thesis provide a good foundation for the development of a more sensitive and specific hip fracture prediction model. With further development, the score could have clinical use for individuals who complete interRAI-HC assessments

Evaluating the influence of social factors on aged residential care admission in a national home care assessment database of older adults

Objectives: Evaluate the influence of social factors on admission to aged residential care (ARC) facilities using a national comprehensive geriatric assessment database in New Zealand. Design: Time-to-event analysis of a continuously recruited national cohort. Participants and setting: An anonymized data extract from a large national database for home care assessments (June 2012–December 2015) was matched with data on mortality and admissions into ARC. Methods: Four key components of psychosocial risk in relation to ARC admission were used for analysis: living alone, negative social interactions, perceived loneliness, and carer stress. Exploratory data analysis was conducted for each of the variables of interest and demographics. Unadjusted and adjusted competing risk regressions were then performed with admission into ARC being the primary outcome, death the competing risk, and remaining at home the survival case. Results: After data cleaning, matching, and applying exclusions, the study population consisted of 54,345 eligible participants. Mean age of participants was 81.9 years (standard deviation 7.4), 62.1% were female, and 88.7% identified as European ethnicity. In the adjusted model, all 4 social factors remained significantly associated with ARC admission, namely: living alone [subhazard ratio (SHR) = 1.43 95% confidence interval (CI) 1.37–1.50]; negative social interactions (SHR = 1.22, 95% CI 1.15–1.30); perceived loneliness (SHR = 1.18, 95% CI 1.13–1.24); and carer stress (SHR = 1.28, 95% CI 1.23–1.34). Conclusions and implications: Interventions targeted at social factors in the context of delaying ARC admission merit further development and evaluation

Risk factors for hip fracture in New Zealand older adults seeking home care services: A national population cross-sectional study

Background: Hip fractures are a common injury in older people. Many studies worldwide have identified various risk factors for hip fracture. However, risk factors for hip fracture have not been studied extensively in New Zealand. The interRAI home care assessment consists of 236 health questions and some of these may be related to hip fracture risk. Methods: The cohort consisted of 45,046 home care clients aged 65 years and older, in New Zealand. Assessments ranged from September 2012 to October 2015. Hip fracture diagnosis was identified by linking ICD (International Classification of Diseases) codes from hospital admissions data (September 2012 to December 2015) to the interRAI home care data. Unadjusted and adjusted competing risk regressions, using the Fine and Gray method were used to identify risk factors for hip fracture. Mortality was the competing event. Results: The cohort consisted of 61% female with a mean age of 82.7 years. A total of 3010 (6.7%) of the cohort sustained a hip fracture after assessment. After adjusting for sociodemographic and potentially confounding variables falls (SHR (Subhazard Ratio) = 1.17, 95% CI (Confidence interval): 1.05-1.31), previous hip fracture (SHR = 4.16, 95% CI: 2.93-5.89), female gender (SHR = 1.38, 95% CI: 1.22-1.55), underweight (SHR = 1.67, 95% CI = 1.39-2.02), tobacco use (SHR = 1.56, 95% CI = 1.25-1.96), Parkinson's disease (SHR = 1.45, 95% CI: 1.14-1.84), and Wandering (SHR = 1.36, 95% CI: 1.07-1.72) were identified as risk factors for hip fracture. Shortness of breath (SHR = 0.80, 95% CI: 0.71-0.90), was identified as being protective against hip fracture risk. Males and females had different significant risk factors. Conclusions: Risk factors for hip fracture similar to international work on risk factors for hip fracture, can be identified using the New Zealand version of the interRAI home care assessment

Profile of ethnicity, living arrangements and loneliness amongst older adults in Aotearoa New Zealand: a national cross-sectional study

To explore the patterns of living arrangements, ethnicity and loneliness amongst older adults (aged 65+ years) living at home.National interRAI-HC (International Residential Assessment Instrument-Home Care) assessments conducted between 1 September 2012 and 31 January 2016 were analysed. Analysis focused on the associations between loneliness and both ethnic groups and living arrangements.There were 71 859 eligible participants, with average age 82.7 years, comprising Māori (5%), Pasifika (3%), Asian (2%) and European/Other (89%) ethnic identification. Most stated that they were not lonely (79%), but those living alone were more likely to be lonely (29%) than those living with others (14%) (P < 0.05). Amongst those living alone, significant differences in the likelihood of being lonely emerged between ethnic groups (P < 0.05).Ethnic identification and living arrangements were significantly associated with the likelihood of loneliness for those having an interRAI-HC assessment. Efforts to reduce the negative impacts of loneliness need a nuanced approach

A frailty index derived from a standardized comprehensive geriatric assessment predicts mortality and aged residential care admission

Abstract Background Frailty in older adults is a condition characterised by a loss or reduction in physiological reserve resulting in increased clinical vulnerability. However, evidence suggests that frailty may be modifiable, and identifying frail older people could help better target specific health care interventions and services. Methods This was a regional longitudinal study to develop a frailty index for older adults living in Canterbury New Zealand. Participants included 5586 community dwelling older people that had an interRAI Minimum Data Set (MDS-HC) Home Care assessment completed between 2008 and 2012. The outcome measures were mortality and entry into aged residential care (ARC), after five years. Results Participants were aged between 65 and 101 (mean age was 82 years). The five-year mortality rate, including those who entered ARC, for this cohort was 67.1% (n = 3747). The relationship between the frailty index and both mortality and entry into ARC was significant (P < 0.001). At five years, 25.1% (n = 98) of people with a baseline frailty of < 0.1 had died compared with 28.2% (n = 22) of those with a frailty index of ≥0.5 (FS 5). Furthermore, 43.7% (n = 171) of people with a frailty index of < 0.1 were still living at home compared to 2.6% (n = 2) of those with a frailty index of ≥0.5. Conclusion A frailty index was created that predicts mortality, and admission into ARC. This index could help healthcare professionals and clinicians identify older people at risk of health decline and mortality, so that appropriate services and interventions may be put in place