A genetic algorithm-based strategic planning framework for optimising accessibility and costs of general practices in Northland, New Zealand.

Shortage of general practitioners (GP) is a challenge worldwide, not only in Europe, but also in countries like New Zealand. Providing primary care in rural areas is especially challenging. In order to support decision makers, it is necessary to first assess the current GP coverage and then to determine different scenarios and plans for the future. In this paper, we first present a thorough overview of related literature on locating GP practices. Second, we propose an approach for assessing the GP coverage and determining future GP locations based on a genetic algorithm framework. As a use case, we have chosen the rural New Zealand region of Northland. We also perform a sensitivity analysis for the main input parameters.

The Older Persons' Index of Multiple Deprivation: Measuring the deprivation circumstances of older populations in Aotearoa New Zealand.

Existing indices of multiple deprivation exclude indicators specifically relevant to the population aged ≥65 years. In this study we create a whole-of-population cohort of people aged ≥65 years living in private dwellings and who completed the 2013 New Zealand Census of Populations and Dwellings to create an Older Persons' Index of Multiple Deprivation (OPIMD). We combined 22 indicators representing 6 domains of deprivation (Income, Housing, Health, Assets, Connectedness and Geographic access) to establish this individual-level measure of deprivation. We used smoking data from the census to validate the OPIMD and describe the geography of the OPIMD by District Health Board, contrasting these patterns with a conventional area deprivation index. The OPIMD has the potential to inform policies concerning resource allocation for the older population. An accompanying website with an interactive atlas and an online OPIMD calculator is available for wider use of the data. Further research is required to explore associations between the OPIMD and other major health and social outcomes affecting this population.

Understanding geographical variations in health system performance: a population-based study on preventable childhood hospitalisations.

OBJECTIVE: To investigate interdistrict variations in childhood ambulatory sensitive hospitalisation (ASH) over the years. DESIGN: Observational population-based study over 2008-2018 using the Primary Health Organisation Enrolment Collection (PHO) and the National Minimum Dataset hospital events databases. SETTING: New Zealand primary and secondary care. PARTICIPANTS: All children aged 0-4 years enrolled in the PHO Enrolment Collection from 2008 to 2018. MAIN OUTCOME MEASURE: ASH. RESULTS: Only 1.4% of the variability in the risk of having childhood ASH (intracluster correlation coefficient=0.014) is explained at the level of District Health Board (DHB), with the median OR of 1.23. No consistent time trend was observed for the adjusted childhood ASH at the national level, but the DHBs demonstrated different trajectories over the years. Ethnicity (being a Pacific child) followed by deprivation demonstrated stronger relationships with childhood ASH than the geography and the health system input variables. CONCLUSION: The variation in childhood ASH is explained only minimal at the DHB level. The sociodemographic variables also only partly explained the variations. Unlike the general ASH measure, the childhood ASH used in this analysis provides insights into the acute conditions sensitive to primary care services. However, further information would be required to conclude this as the DHB-level performance variations.

Epidemiology of dog-related injuries within New Zealand.

AIM: To describe the epidemiology of DRIs in New Zealand. METHODS: A review of Accident Compensation Corporation (ACC) new claims for DRIs that required medical attention, and publicly funded hospital discharges identified from the National Minimum Dataset (NMDS) for the period of 1 July 2014 to 30 June 2019. ACC cases were identified using the TE60 READ code and relevant diagnosis or external agency descriptions; NMDS cases with an ICD-10-AM external cause of injury code of W540, W541, or W548 were included. RESULTS: There were 108,324 new ACC claims for DRIs and 3,456 hospitalisations during the five-year review period. The majority of injuries were dog bites (51%, n=54,754 ACC claims; 89%, n=3,084 hospitalisations). The all-age incidence of ACC claims for all DRIs significantly increased by 1.75% per year (p<0.001) during the period reviewed, with a significant increase in claims for dog bite injuries of 1.64% per year (p<0.001), a significant increase in DRI hospitalisations (2.43% per year, p=0.046), and a non-significant annual increase (p=0.217) in dog bite injury hospitalisations. Children aged 0-9 years had similar rates to adults of ACC claims for dog bite injuries; however, children 0-9 years were more likely to be hospitalised. Maori had a higher incidence of ACC claims and hospitalisations for dog bite injuries than non-Maori. ACC claims and hospitalisations for dog bite injuries were more likely to occur in areas of greater deprivation, with substantial regional variation across the country. CONCLUSION: The incidence of injury from dogs in New Zealand is increasing. Inequity exists with substantial regional variation, in higher rates among those living in areas of greater deprivation, and with Maori in the setting of the ongoing effects of colonisation. Children aged 0-9 years are no more likely than other age groups to present for medical attention but are more likely to be hospitalised. Reasons for these disparities require further investigation.

Suicide preceded by health services contact - A whole-of-population study in New Zealand 2013-2015.

New Zealand's rate of suicide persistently exceeds the global average. The burden of suicide in New Zealand is disproportionately borne by youth, males and Maori (NZ indigenous people). While the demographic characteristics of suicide decedents are established, there is a need to identify potential points of contact with health services where preventative action could take place. This paper aims to determine if suicide deaths in New Zealand were likely to be preceded by contact with health services, and the type and time frame in which these contacts took place. This study utilised a whole-of-population-cohort of all individuals age 15 years and over, who were alive on March 5th 2013, followed up to December 2015. Associations between the odds of suicide, demographic factors, area-based deprivation, and the timing of last contact with primary, secondary, and tertiary services were analysed using univariate and multivariate logistic regression. Contact with a health service in the 6 Months prior to death was associated with the highest odds of suicide. Over half of the suicide decedent population (59.4%) had contacted primary health services during this period. Large proportions of the suicide decedent population contacted secondary and tertiary services in the 6 Months prior to death, 46.5% and 30.4% respectively. Contact with primary, secondary and tertiary services in the prior 6 Months, were associated with an increased odds of suicide of 2.51 times [95% CI 2.19-2.88], 4.45 times [95% CI 3.69-4.66] and 6.57 times [95% CI 5.84-7.38], respectively, compared to those who had no health services contact.

Charting elimination in the pandemic: a SARS-CoV-2 serosurvey of blood donors in New Zealand.

New Zealand has a strategy of eliminating SARS-CoV-2 that has resulted in a low incidence of reported coronavirus-19 disease (COVID-19). The aim of this study was to describe the spread of SARS-CoV-2 in New Zealand via a nationwide serosurvey of blood donors. Samples (n = 9806) were collected over a month-long period (3 December 2020-6 January 2021) from donors aged 16-88 years. The sample population was geographically spread, covering 16 of 20 district health board regions. A series of Spike-based immunoassays were utilised, and the serological testing algorithm was optimised for specificity given New Zealand is a low prevalence setting. Eighteen samples were seropositive for SARS-CoV-2 antibodies, six of which were retrospectively matched to previously confirmed COVID-19 cases. A further four were from donors that travelled to settings with a high risk of SARS-CoV-2 exposure, suggesting likely infection outside New Zealand. The remaining eight seropositive samples were from seven different district health regions for a true seroprevalence estimate, adjusted for test sensitivity and specificity, of 0.103% (95% confidence interval, 0.09-0.12%). The very low seroprevalence is consistent with limited undetected community transmission and provides robust, serological evidence to support New Zealand's successful elimination strategy for COVID-19.

The nature of police shootings in New Zealand: A comparison of mental health and non-mental health events.

The use of firearms by police in mental health-related events has not been previously researched in New Zealand. This study analysed reports of investigations carried out by the Independent Police Conduct Authority between 1995 and 2019. We extracted data relating to mental health state, demographics, setting, police response, outcome of shooting, and whether the individual was known to police, mental health services, and with a history of mental distress or drug use. Of the 258 reports analysed, 47 (18%) involved mental health-related events compared to 211 (82%) classified as non-mental health events. Nineteen (40.4%) of the 47 mental health events resulted in shootings, compared to 31 (14.8%) of the 211 non-mental health events. Of the 50 cases that involved shootings 38% (n = 19) were identified as mental health events compared to 62% (n = 31) non-mental health events. Over half of the mental health events (n = 11, 57.9%) resulted in fatalities, compared to 35.5% (n = 11) of the non-mental health events. Cases predominantly involved young males. We could not ascertain the ethnicity of individuals from the IPCA reports. Across all shooting events, a high proportion of individuals possessed a weapon, predominantly either a firearm or a knife, and just under half were known to police and had known substance use. Of the 19 mental health events, 47.4% (n = 9) of individuals were known to mental health services and in 89.5% (n = 17) of cases whanau (family) were aware of the individual's current (at the time of the event) mental health distress and/or history. These findings suggest opportunities to prevent the escalation of events to the point where they involve shootings. Lack of ethnicity data limits the accountability of the IPCA and is an impediment to informed discussion of police response to people of different ethnicities, and Maori in particular, in New Zealand.

Ethnic differences in cardiovascular risk profiles among 475,241 adults in primary care in Aotearoa, New Zealand.

AIM: In Aotearoa, New Zealand, cardiovascular disease (CVD) burden is greatest among Indigenous Maori, Pacific and Indian people. The aim of this study was to describe CVD risk profiles by ethnicity. METHODS: We conducted a cross-sectional analysis of a cohort of people aged 35-74 years who had a CVD risk assessment in primary care between 2004 and 2016. Primary care data were supplemented with linked data from regional/national databases. Comparisons between ethnic groups were made using age-adjusted summaries of continuous or categorical data. RESULTS: 475,241 people (43% women) were included. Fourteen percent were Maori, 13% Pacific, 8% Indian, 10% Other Asian and 55% European. Maori and Pacific people had a much higher prevalence of smoking, obesity, heart failure, atrial fibrillation and prior CVD compared with other ethnic groups. Pacific and Indian peoples, and to a lesser extent Maori and Other Asian people, had markedly elevated diabetes prevalence compared with Europeans. Indian men had the highest prevalence of prior coronary heart disease. CONCLUSIONS: Maori and Pacific people experience the most significant inequities in exposure to CVD risk factors compared with other ethnic groups. Indians have a high prevalence of diabetes and coronary heart disease. Strong political commitment and cross-sectoral action to implement effective interventions are urgently needed.

Spatially explicit models for exploring COVID-19 lockdown strategies.

This article describes two spatially explicit models created to allow experimentation with different societal responses to the COVID-19 pandemic. We outline the work to date on modeling spatially explicit infective diseases and show that there are gaps that remain important to fill. We demonstrate how geographical regions, rather than a single, national approach, are likely to lead to better outcomes for the population. We provide a full account of how our models function, and how they can be used to explore many different aspects of contagion, including: experimenting with different lockdown measures, with connectivity between places, with the tracing of disease clusters, and the use of improved contact tracing and isolation. We provide comprehensive results showing the use of these models in given scenarios, and conclude that explicitly regionalized models for mitigation provide significant advantages over a "one-size-fits-all" approach. We have made our models, and their data, publicly available for others to use in their own locales, with the hope of providing the tools needed for geographers to have a voice during this difficult time.

Predicting Lipid-Lowering Medication Persistence after the First Cardiovascular Disease Hospitalization.

OBJECTIVES: This study analyzed patient factors in medication persistence after discharge from the first hospitalization for cardiovascular disease (CVD) with the aim of predicting persistence to lipid-lowering therapy for 1 to 2 years. METHODS: A subcohort having a first CVD hospitalization was selected from 313,207 patients for proportional hazard model analysis. Logistic regression, support vector machine, artificial neural networks, and boosted regression tree (BRT) models were used to predict 1- and 2-year medication persistence. RESULTS: Proportional hazard modeling found significant association of persistence with age, diabetes history, complication and comorbidity level, days stayed in hospital, CVD diagnosis type, in-patient procedures, and being new to therapy. BRT had the best predictive performance with c-statistic of 0.811 (0.799-0.824) for 1-year and 0.793 (0.772-0.814) for 2-year prediction using variables potentially available shortly after discharge. CONCLUSION: The results suggest that development of a machine learning-based clinical decision support tool to focus improvements in secondary prevention of CVD is feasible.

Prevalence and geographical variation of dementia in New Zealand from 2012 to 2015: Brief report utilising routinely collected data within the Integrated Data Infrastructure.

OBJECTIVES: There are no national dementia epidemiological studies using New Zealand (NZ) data. NZ routinely collects health-care data within the Integrated Data Infrastructure (IDI). The study objectives were to 1) investigate late-onset dementia estimates using the IDI between 2012-2015 and compare these with 2) published estimates, and 3) variations between North and South Islands and ethnicity. METHODS: A population-based, retrospective cohort design was applied to routinely collected de-identified health/administrative IDI data. Dementia was defined by ICD-10-AM dementia codes or anti-dementia drugs. RESULTS: Approximately 2% of those aged ≥60 years had dementia, lower than published estimates. Dementia was higher in North Island; in 80- to 89-year-olds; among the Maori population when age-standardised, and 9% of all dementia cases had >1 dementia sub-type. CONCLUSIONS: To our knowledge, this is the first study ascertaining dementia estimates using NZ's whole-of-population IDI data. Estimates were lower than existing NZ estimates, for several reasons. Further work is required, including expanding IDI data sets, to develop future estimates that better reflect NZ's diverse population.

Deprivation matters: understanding associations between neighbourhood deprivation, unhealthy food outlets, unhealthy dietary behaviours and child body size using structural equation modelling.

BACKGROUND: Children residing in neighbourhoods of high deprivation are more likely to have poorer health, including excess body size. While the availability of unhealthy food outlets are increasingly considered important for excess child body size, less is known about how neighbourhood deprivation, unhealthy food outlets and unhealthy dietary behaviours are interlinked. METHODS: This study involves children aged 8-13 years (n=1029) and resided in Auckland, New Zealand. Unhealthy dietary behaviours (frequency of consumption of unhealthy snacks and drinks) and food purchasing behaviour on the route to and from school were self-reported. Height and waist circumference were measured to calculate waist-to-height ratio (WtHR). Geographic Information Systems mapped neighbourhood deprivation and unhealthy food outlets within individual, child-specific neighbourhood buffer boundaries (800 m around the home and school). Associations between neighbourhood deprivation (calculated using the New Zealand Index of Deprivation 2013), unhealthy food outlets, unhealthy dietary behaviours and WtHR were investigated using structural equation modelling in Mplus V.8.0. Age, sex and ethnicity were included as covariates, and clustering was accounted for at the school level. RESULTS: Structural equation models showed that unhealthy food outlets were unrelated to unhealthy dietary behaviours (estimate 0.029, p=0.416) and excess body size (estimate -0.038, p=0.400). However, greater neighbourhood deprivation and poorer dietary behaviours (estimate -0.134, p=0.001) were associated with greater WtHR (estimate 0.169, p<0.001). CONCLUSION: Excess child body size is associated with neighbourhood deprivation and unhealthy dietary behaviours but not unhealthy outlet density or location of these outlets near home and school.

Interrupted time series analysis on first cardiovascular disease hospitalization for adherence to lipid-lowering therapy.

PURPOSE: We analysed lipid-lowering medication adherence before and after the first hospitalization for cardiovascular disease (CVD) to explore the influence hospitalization has on patient medication adherence. METHODS: We extracted a sub-cohort for analysis from 313,207 patients who had primary CVD risk assessment. Adherence was assessed as proportion of days covered (PDC) ≥ 80% based on community dispensing records. Adherence in the 4 quarters (360 days) before the first CVD hospitalization and 8 quarters (720 days) after hospital discharge was assessed for each individual in the sub-cohort. An interrupted time series design using generalized estimating equations was applied to compare the differences of population-level medication adherence rates before and after the first CVD hospitalization. RESULTS: Overall, a significant improvement in medication adherence rate from before to after the hospitalization was observed (odds ratio (OR) 2.49 [1.74-3.57]) among the 946 patients included in the analysis. Patients having diabetes history had a higher OR of adherence before the hospitalization than patients without diabetes (1.50 [1.03-2.22]) but no significant difference after the hospitalization (OR 1.13 [0.89-1.43]). Before the first hospitalization, we observed that quarterly medication adherence rate was steady at around 55% (OR 0.97 [0.93-1.01), whereas the trend in adherence over the post-hospitalization period decreased significantly per quarter (OR 0.97 [0.94-0.99]). CONCLUSIONS: Patients were more likely to adhere to lipid-lowering therapy after experiencing a first CVD hospitalization. The change in medication adherence rate is consistent with patients having heightened perception of disease severity following the hospitalization.

Can a short neuromuscular warmup before tackling improve shoulder joint position sense in rugby players?

BACKGROUND: In rugby the tackle is a complex task requiring joint position sense (JPS). Injuries commonly occur during the tackle and these account for significant time lost from training and play. Simulated tackling tasks have previously shown a reduction in shoulder joint position sense and it is possible that this may contribute to injury. There is growing evidence in support of injury prevention programs, but none so far are dedicated specifically to tackling. We postulate that a brief neuromuscular warmup could alter the negative effects of fatigue on shoulder JPS. METHODS: In this field based, repeated measures design study, 25 semi-professional Rugby players participated. JPS was measured at criterion angles of 45° and 80° of right arm shoulder external rotation. Reproduction accuracy prior to and following a neuromuscular warmup and simulated tackling task was then assessed. RESULTS: In pre-warmup JPS measures, the spread of angle errors were larger at the 80° positions. Adding the warmup, the spread of the angle errors at the 80° positions decreased compared to pre-intervention measures. Two one-sided tests (TOST) analysis comparing pre- and post-testing angle errors, with the addition of the warmup, indicated no difference in JPS. CONCLUSIONS: The neuromuscular warmup resulted in a decrease in JPS error variance meaning fewer individuals made extreme errors. The TOST analysis results also suggest the neuromuscular warmup used in this study could mitigate the negative effects of tackling on JPS that has been seen in prior research. This neuromuscular warmup could play a role in preventing shoulder injuries. It can easily be added to existing successful injury prevention programs.

Self-management action and motivation of Pacific adults in New Zealand with end-stage renal disease.

AIMS: To explore actions and motivations for self-management practices of Pacific adults following diagnosis of end stage renal disease (ESRD). METHODS: Focused ethnography using in-depth interviews with 16 Pacific people on haemodialysis for diabetic ESRD, in Auckland, New Zealand. Study participants were of Samoan, Cook Islander, Tongan, Niuean, or Tokelauan ethnicity and aged between 30 to 69 years old. Thematic analysis was used to code and identify emergent themes. RESULTS: All participants assumed active responsibility for their self-management following their diagnosis of ESRD. They reported positive differences in their current self-management behaviours, compared to pre-ESRD diagnosis. In the face of their terminal diagnosis, participant's motivations to self-manage their health were fuelled by hope; the hope to live long enough to change their family legacy of diabetes and ESRD. To achieve this, there was a dependency upon family members as a resource for self-management support. Yet at the same time, family members also had health concerns (including diabetes), and several participants themselves were carers for sick or elderly family members. CONCLUSION: The growing number of members (within family units) progressing from moderate to late-stage diabetes raises concerns about the sustainability of future family support in Pacific families in New Zealand with histories of diabetes, ESRD, and other chronic diseases. While the burden upon informal carers (family) has been well documented throughout the past few decades, the dynamics of bi-directional carer support between (two or more) sick family members and their families have had less exposure. This has potentially significant implications for Pacific peoples in New Zealand, considering the increases in diabetes prevalence within their families.

Understandings of disease among Pacific peoples with diabetes and end-stage renal disease in New Zealand.

BACKGROUND: Compared with New Zealand Europeans, Pacific peoples in New Zealand develop type 2 diabetes at a higher rate and a younger age, and have 3.8 times higher incidence of end-stage renal disease (ESRD). OBJECTIVE: To investigate contextual factors that shape understandings of disease for Pacific peoples with diabetes and ESRD. METHODS: Focussed ethnography. In-depth interviews were conducted with 16 Pacific people on haemodialysis for diabetic ESRD, in Auckland, New Zealand. Study participants aged between 30 and 69 years old were of Samoan, Cook Islander, Tongan, Niuean or Tokelauan ethnicity. Thematic analysis was used to code and identify themes. RESULTS: Participants were embedded in a multigenerational legacy of diabetes. The limited diabetes-related education of earlier generations influenced how future generations behaved and understood diabetes. Perceptions were compounded by additional factors including the invisibility of early-stage diabetes; misunderstandings of health risks during communication with health providers; and misunderstandings of multiple conditions' symptoms and management. Participants had limited engagement with health services until their diagnosis of ESRD acted as a trigger to change this behaviour. However, this trigger was not effective in itself-rather, it was in combination with relevant education delivered in a way that made sense to participants, given their current understandings. CONCLUSIONS: Illness representations drive choices and behaviours with respect to self-management of diabetes and engagement with health services. Diabetes is often present in multiple generations of Pacific people; therefore, illness representations are developed and shared within a family. Changing illness representations requires engagement with the individual within a family context.

Acute myocardial infarction: Does survival depend on geographical location and social background?

AIMS: This study described the interplay between geographical and social inequalities in survival after incident acute myocardial infarction (AMI) and examined whether geographical variation in survival exists when accounting for sociodemographic characteristics of the patients and their neighbourhood. METHODS: Ringmap visualization and generalized linear models were performed to study post-AMI mortality. Three individual-level analyses were conducted: immediate case fatality, mortality between days 1 and 28 after admission and 365-day survival among patients who survived 28 days after admission. RESULTS: In total, 99,013 incident AMI cases were registered between 2005 and 2014 in Denmark. Survival after AMI tended to correlate with sociodemographic indicators at the municipality level. In individual-level models, geographical inequality in immediate case fatality was observed with high mortality in northern parts of Jutland after accounting for sociodemographic characteristics. In contrast, no geographical variation in survival was observed among patients who survived 28 days. In all three analyses, odds and rates of mortality were higher among patients with low educational level (odds ratio (OR) (95% credible intervals) of 1.20 (1.12-1.29), OR of 1.12 (1.01-1.24) and mortality rate ratio of 1.45 (1.30-1.61)) and low income (OR of 1.24 (1.15-1.33), OR of 1.33 (1.20-1.48) and mortality rate ratio of 1.25 (1.13-1.38)). CONCLUSION: Marked geographical inequality was observed in immediate case fatality. However, no geographically unequal distribution of survival was found among patients who survived 28 days after AMI. Results additionally showed social inequality in survival following AMI.

Geography and patient history in long-term lipid lowering medication adherence for primary prevention of cardiovascular disease.

In order to determine the role of geographical and patient history factors in long-term medication adherence in cardiovascular disease (CVD), we analysed adherence to lipid-lowering therapy in a primary care cohort based on CVD decision support and linked health systems and census data from Auckland, New Zealand. Two-year adherence was examined for 10,410 patients aged between 30 and 74 with neither diabetes nor a history of CVD. Using logistic regression we found significant variation in adherence by age, ethnicity and being a new therapy user, and in 9 of 86 geographic zones. A large low-adherence 'cold-spot' of 13 contiguous geographic zones was detected through local Getis-Ord Gi* analysis. A set of 42 models to predict adherence was formulated on sets of demographic, geographic and refill history factors. We observed prediction ability to be improved by addition of refill history but not geographical variables, and boosted regression tree (BRT) models outperformed logistic regression.

Different domains of deprivation and their relationship with obesity in New Zealand 4-year-old children.

BACKGROUND: There is a relationship between childhood obesity and area-level deprivation. While the New Zealand Index of Deprivation (NZDep) has been used widely in research for the past 20 years, the Index of Multiple Deprivation (IMD) was released in 2017. This study aims to investigate the association between deprivation and childhood obesity in New Zealand and compare measures of deprivation. METHODS: Data from 316 794 4-year-olds in New Zealand undertaking the B4 School Check in 2010 to 2016, a national health and development screen, were analysed. Multilevel logistic regression models assessed the relationship between area-level deprivation and individual-level child obesity. Models were adjusted for age, sex, immigration status, ethnicity, and year. Deprivation was measured using the census-based NZDep2013 (deciles) and the administrative data-based IMD (deciles). The seven domains of the IMD were also considered. RESULTS: The relationship between deprivation and obesity was very similar for the IMD and NZDep2013, point estimates were near identical, and confidence intervals overlapped substantially. Higher levels of deprivation were associated with a higher prevalence of child obesity. The relationship between deprivation and child obesity varied considerably across IMD domains. The education domain had the strongest association with child obesity and had an association with child obesity independent of the other domains of deprivation. CONCLUSION: Overall, there was little difference between the NZDep and IMD. However, the IMD's domains and IMD-1 approach reveal more nuanced understandings of the deprivation-obesity gradient, including the importance of area-level education deprivation for predicting child obesity rates.