Collaborating with a social housing provider supports a large cohort study of the health effects of housing conditions.

BACKGROUND: Despite the importance of adequate, un-crowded housing as a prerequisite for good health, few large cohort studies have explored the health effects of housing conditions. The Social Housing Outcomes Worth (SHOW) Study was established to assess the relationship between housing conditions and health, particularly between household crowding and infectious diseases. This paper reports on the methods and feasibility of using a large administrative housing database for epidemiological research and the characteristics of the social housing population. METHODS: This prospective open cohort study was established in 2003 in collaboration with Housing New Zealand Corporation which provides housing for approximately 5% of the population. The Study measures health outcomes using linked anonymised hospitalisation and mortality records provided by the New Zealand Ministry of Health. RESULTS: It was possible to match the majority (96%) of applicant and tenant household members with their National Health Index (NHI) number allowing linkage to anonymised coded data on their hospitalisations and mortality. By December 2011, the study population consisted of 11,196 applicants and 196,612 tenants. Half were less than 21 years of age. About two-thirds identified as Maori or Pacific ethnicity. Household incomes were low. Of tenant households, 44% containing one or more smokers compared with 33% for New Zealand as a whole. Exposure to household crowding, as measured by a deficit of one or more bedrooms, was common for applicants (52%) and tenants (38%) compared with New Zealanders as whole (10%). CONCLUSIONS: This project has shown that an administrative housing database can be used to form a large cohort population and successfully link cohort members to their health records in a way that meets confidentiality and ethical requirements. This study also confirms that social housing tenants are a highly deprived population with relatively low incomes and high levels of exposure to household crowding and environmental tobacco smoke.

Is the use of health services by older adults in New Zealand associated with their housing tenure?

AIM: To explore associations between tenure and the health service use of older New Zealanders. METHODS: Analysis of pooled data for adults aged 55+ from three New Zealand Health Surveys (2013/14, 2014/15, 2015/16) comparing owner-occupiers, private renters and public renters. RESULTS: Public renters, and in some age groups private renters, reported more visits to the GP and a higher proportion reported using a public hospital service in the last year. Renters were less likely than owner-occupiers to have used some privately paid services (visiting a dental health worker or optician). Renters averaged lower co-payments for their last GP visit, but financial barriers to accessing a GP, after-hours medical centre use and not collecting prescriptions were more likely to be reported by renters than owner-occupiers-particularly those that rent publicly. CONCLUSIONS: New Zealanders are simultaneously living longer while having declining opportunities to enter home ownership. Older renters are more likely to live in poorer health and, overall, are more likely to use some (public) health services than owner-occupiers yet are more likely to have unmet health needs. The increasing reliance on renting among older people has implications for population health and wellbeing, health service delivery and transitions to residential care.

The health of older New Zealanders in relation to housing tenure: analysis of pooled data from three consecutive, annual New Zealand Health Surveys.

OBJECTIVE: To explore relationships between the housing tenure of older New Zealanders and their health-related behaviours, and physical and mental health. METHODS: Pooled data were analysed for 15,626 older adults (aged 55+) from three consecutive, annual, nationally representative New Zealand Health Surveys to compare owner-occupiers, private renters and public renters. RESULTS: Most in the sample were owner-occupiers (83.2%), with 12.4% private renters and 4.5% public renters. A higher proportion of renters aged 75+ were female. Maori and Pacific people were more likely to be renters. Renters were more likely to be living alone, on lower annual incomes. Overall measures of physical and mental health showed a health gradient, with public renters in the poorest health and owner-occupiers in the best health. CONCLUSIONS: Rental tenure is associated with poorer health. Implications for public health: Older renters tend to be economically disadvantaged and in poorer health than owner-occupiers. Over time, the proportion of older renters has been increasing. This will have implications for policy and for services in meeting the diverse care and support needs of older people. Higher rates of renting among Maori and Pacific people and older females means that these groups are particularly vulnerable to any negative impact of renting on health.

Effect of insulating existing houses on health inequality: cluster randomised study in the community.

OBJECTIVE: To determine whether insulating existing houses increases indoor temperatures and improves occupants' health and wellbeing. DESIGN: Community based, cluster, single blinded randomised study. SETTING: Seven low income communities in New Zealand. PARTICIPANTS: 1350 households containing 4407 participants. INTERVENTION: Installation of a standard retrofit insulation package. MAIN OUTCOME MEASURES: Indoor temperature and relative humidity, energy consumption, self reported health, wheezing, days off school and work, visits to general practitioners, and admissions to hospital. RESULTS: Insulation was associated with a small increase in bedroom temperatures during the winter (0.5 degrees C) and decreased relative humidity (-2.3%), despite energy consumption in insulated houses being 81% of that in uninsulated houses. Bedroom temperatures were below 10 degrees C for 1.7 fewer hours each day in insulated homes than in uninsulated ones. These changes were associated with reduced odds in the insulated homes of fair or poor self rated health (adjusted odds ratio 0.50, 95% confidence interval 0.38 to 0.68), self reports of wheezing in the past three months (0.57, 0.47 to 0.70), self reports of children taking a day off school (0.49, 0.31 to 0.80), and self reports of adults taking a day off work (0.62, 0.46 to 0.83). Visits to general practitioners were less often reported by occupants of insulated homes (0.73, 0.62 to 0.87). Hospital admissions for respiratory conditions were also reduced (0.53, 0.22 to 1.29), but this reduction was not statistically significant (P=0.16). CONCLUSION: Insulating existing houses led to a significantly warmer, drier indoor environment and resulted in improved self rated health, self reported wheezing, days off school and work, and visits to general practitioners as well as a trend for fewer hospital admissions for respiratory conditions.