Impact of improved insulation and heating on mortality risk of older cohort members with prior cardiovascular or respiratory hospitalisations

Abstract

ObjectivesWe carried out an evaluation of a large-scale New Zealand retrofit programme using administrative data that provided the statistical power to assess the effect of insulation and/or heating retrofits on cardiovascular and respiratory-related mortality in people aged 65 and over with prior respiratory or circulatory hospitalisations.DesignQuasi-experimental cohort study based on administrative data.SettingNew Zealand.ParticipantsFrom a larger study cohort of over 900 000 people, we selected two subcohorts: 3287 people who were aged 65 and over and had experienced pretreatment period cardiovascular-related hospitalisation (ICD-10 chapter 9), and 1561 people aged 65 and over who had experienced pretreatment respiratory-related hospitalisation (ICD-10 chapter 10).InterventionsTreatment group individuals lived in a home that received insulation and/or heating retrofits under the Warm Up New Zealand: Heat Smart programme. Control group individuals lived in a home that was matched to a treatment home based on physical characteristics and location.Primary and secondary outcome measuresHR for all-cause mortality for treatment with insulation, heating, or insulation and heating relative to control group.ResultsPeople with pretreatment circulatory hospitalisation who occupied a household that received only insulation had an HR for all-cause mortality of 0.673 (95% CI 0.535 to 0.847) (p<0.001) relative to control group members. Individuals with a pretreatment respiratory hospitalisation who occupied a household that received only an insulation retrofit had an HR for all-cause mortality of 0.830 (95% CI 0.655 to 1.051) (p=0.122) relative to control group members. There was no evidence of an additional benefit from receiving heating.ConclusionsWe interpret the hazard rate observed for cardiovascular subcohort individuals who received insulation as evidence of a protective effect, reducing the risk of mortality for vulnerable older adults. There is suggestive evidence of a protective effect of insulation for the respiratory subcohort.

How Economic Analysis Can Contribute to Understanding the Links between Housing and Health

“…Valuing reductions in mortality captured what proved to be the largest health benefit in a CBA of the WUNZ programme: in discounted net present value terms the programme gave a very favourable benefit cost ratio of close to 4:1 [ 53 ]. Indeed, further analysis suggests that, driven by mortality reductions for people over 65 years of age who had been hospitalised with pre-existing circulatory conditions in the previous year, the benefit cost ratio might be as high as 6.4:1 [ 54 ]. It is interesting to note that in the absence of a suitably large administrative dataset it would have been impossible to capture this benefit, leading to an incomplete CBA and quite possibly to an end of the WUNZ programme earlier than has been scheduled.…”

Government failure and success: A trans-Tasman comparison of two insulation subsidy schemes

“…and Kennedy, 2009;Howden-Chapman et al, 2007, 2008. Subsequent evaluations confirmed that the program produced both energy savings (Grimes et al, 2016) and health benefits (Preval, 2012(Preval, , 2015Preval et al, 2017;Telfar Barnard et al, 2011). The program was subsequently continued as Warm Up New Zealand: Healthy Homes with reduced funding (EECA, 2013) and has more recently been continued under the incoming Labour Government.…”

A Review of the Relation between Household Indoor Temperature and Health Outcomes

“…building envelope-indoor temperature [27,29,40,44,[46][47][48] Energies 2020, 13, x FOR PEER REVIEW 7 of 23…”

“…This means that most studies take into consideration the influence and interconnection with outdoor temperatures or climate (link 1). The higher relevance assigned to socioeconomic factors-indoor temperature and indoor temperature-health outcome (links 4 and 5) socioeconomic factor-indoor temperature [27,29,[39][40][41][42][43][44][45][46][47][48][49][50] Energies 2020, 13, x FOR PEER REVIEW 7 of 23…”

“…Table 1 presents the studies addressing each one of the links described in Figure 3 and 264 summarises the identified energy efficiency-indoor temperature-health outcomes. [22] energy efficiency upgrade-low indoor temperature-emergency hospital admissions cardiovascular and respiratory conditions and injuries [27] energy efficiency upgrade-low indoor temperature-cardiovascular and respiratory health related conditions outdoor temperature-cardiovascular and respiratory-related mortality and morbidity [29] high indoor temperature-emergency hospital admissions cardiovascular and respiratory conditions; psychosocial impacts [39] low indoor temperature-emergency care for cardiovascular and respiratory conditions [40] low indoor temperature-cardiovascular and mental health related biomarkers [41] low indoor temperature-cardiovascular and mental health related biomarkers [42] low indoor temperature-cardiovascular and mental health related biomarkers [43] low indoor temperature-cardiovascular related biomarkers [44] high indoor temperature-heat-related health symptoms [45] low indoor temperature-long term health disabilities [46] energy efficiency upgrades-low indoor temperature cardiovascular and respiratory-related mortality [47] energy efficiency upgrade-low indoor temperature general health; respiratoryrelated conditions and general practitioner's hospital admissions [48] energy efficiency upgrade-low indoor temperature-respiratory related conditions, general health status hospital admissions [49] low indoor temperature-cardiovascular related biomarkers [50] low indoor temperature-cardiovascular related biomarkers…”