Excess Winter Research Articles

Excess winter mortality in Finland, 1971–2019: a register-based study on long-term trends and effect modification by sociodemographic characteristics and pre-existing health conditions

ObjectivesExcess winter mortality is a well-established phenomenon across the developed world. However, whether individual-level factors increase vulnerability to the effects of winter remains inadequately examined. Our aim was to assess...

The impacts of extreme temperature on mortality and emergency hospital admissions within East Sussex in comparison with pre-existing national trends.

The impacts of heatwaves are a rapidly growing area of study; however, much of the existing research focusses on national data analysis. This article aims to add a local perspective using data from only one county, East Sussex, and comparing these with the pre-existing national data. Population data were obtained from publicly available sources such as the Office of National Statistics, in addition to anonymized data from patients. Statistical analysis calculated excess mortality and emergency hospital admissions associated with both winter and heatwaves. Further analyses into factors associated with worse health outcomes in pre-existing data, such as the extremes of age (under 1s and over 75s), dementia and respiratory conditions, were conducted and their effect on excess mortality and emergency admissions was compared with national data. Excess winter mortality within East Sussex averaged 22.5%. Excess heatwave mortality averaged 17%, measuring higher than national data. The relative significance of these data is expected to increase over the next 30years in line with the UK Health Security Agency projection of heat-related mortality tripling by 2050 in the context of global warming and increasing temperatures. Although the number of residents dying or requiring emergency admission due to cold weather is larger than that of heatwaves, trends show a worsening impact of heatwaves. The results of this report are significant findings which show more action is required to mitigate the effects of extreme heat.

The rise and fall of excess winter mortality in New Zealand from 1876 to 2020

Excess winter mortality (EWM) has been used as a measure of how well populations and policy moderate the health effects of cold weather. We aimed to investigate long-term changes in the EWM of Aotearoa New Zealand (NZ), and potential drivers of change, and to test for structural breaks in trends. We calculated NZ EWM indices from 1876 (4,698 deaths) to 2020 (33,310 deaths), total and by age-group and sex, comparing deaths from June to September (the coldest months) to deaths from February to May and October to January. The mean age and sex-standardised EWM Index (EWMI) for the full study period, excluding 1918, was 1.22. However, mean EWMI increased from 1.20 for 1886 to 1917, to 1.34 for the 1920s, then reduced over time to 1.14 in the 2010s, with excess winter deaths averaging 4.5% of annual deaths (1,450 deaths per year) in the 2010s, compared to 7.9% in the 1920s. Children under 5 years transitioned from a summer to winter excess between 1886 and 1911. Otherwise, the EWMI age-distribution was J-shaped in all time periods. Structural break testing showed the 1918 influenza pandemic strain had a significant impact on trends in winter and non-winter mortality and winter excess for subsequent decades. It was not possible to attribute the post-1918 reduction in EWM to any single factor among improved living standards, reduced severe respiratory infections, or climate change.

Assessing the Impact of Energy and Fuel Poverty on Health: A European Scoping Review

Abstract Background The burden of energy and fuel poverty (EFP) in Europe is increasing in the face of the cost-of-living crisis, Russian invasion of Ukraine, COVID-19 pandemic, and climate emergency. While the health impacts of EFP are often the driving reason for addressing it, EFP's association with health is poorly delineated. This review aims to scope the evidence of EFP's association with health in Europe. Methods A scoping review based on Arksey and O'Malley's framework was conducted using search terms relevant to EFP, health, and Europe. Five databases were searched, in addition to hand searching. Review selection was performed by two independent reviewers and articles were thematically analysed. Results Thirty-five articles published between January 2000 and March 2022 were included. The literature varied in definitions and measurements of EFP, and in the health indicators examined. The review revealed a negative association between EFP and health, specifically, general unspecified poor health (9 articles), excess winter mortality (3 articles), communicable disease (3 articles), non-communicable diseases (11 articles), mental health (15 articles), and wellbeing (11 articles). While women were reported to be at higher risk of EFP than men, children and older adults were identified as particularly vulnerable to EFP's adverse health repercussions. Conclusions This scoping review illustrates a significant and complex association between EFP and various domains of health. Though heterogeneity across research makes it difficult to compare findings, our review supports the use of health as a justification to address EFP and urges public health to be more involved in EFP mitigation. Key messages • This scoping review revealed a clear association between EFP and various domains of health, including mental (e.g., anxiety and depression) and physical health (e.g., cardiovascular disease and flu). • We recommend health systems, health professionals, and public health broadly as a field be more involved in working to confront EFP.

Learning from the Past: The Impacts of Economic Crises on Energy Poverty Mortality and Rural Vulnerability

The summer-dominated Mediterranean island of Cyprus is often considered in the contexts of beach tourism, sunny weather, and different types of business economic activities and services. In terms of its climatic conditions, extreme heat and mild winters characterise the island; yet, recent evidence has shown that winter poses a significant threat to public health. Its excess winter mortality is amongst the highest in Europe and there is an increased risk of energy-poverty-related mortality compared to total mortality. This study is an extension of previous research, with the objective of further scrutinizing the shift observed between urban and rural energy poverty mortality in the time of a severe nationwide financial crisis. Mortality and temperature data for the period of 2008–2018, as well as macroeconomic indicators, were investigated through a linear regression analysis. The results indicated that the declining economic situation of the island severely hit rural areas, with a significant increase in energy-poverty-related mortality, while urban areas were more resilient to this. There are three existing challenges linked to energy poverty: low incomes, high energy prices, and poor building energy efficiency. In Cyprus, all three coincide and are aggravated in times of crisis, creating conditions of extreme vulnerability for populations already in a disadvantaged position. This study’s motivation was to highlight the intense vulnerability associated with crises in Cyprus, and its outcomes call for higher levels of support at such times, especially when it comes to rural populations.

Could some vaccines have unanticipated effects against NHS winter pressures?

Journal of Paramedic PracticeVol. 15, No. 6 CommentCould some vaccines have unanticipated effects against NHS winter pressures?Rodney JonesRodney JonesEmail:E-mail Address: [email protected]Statistical Advisor, Healthcare Analysis & ForecastingSearch for more papers by this authorRodney JonesPublished Online:2 Jun 2023https://doi.org/10.12968/jpar.2023.15.6.251AboutSectionsView articleView Full TextPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareShare onFacebookTwitterLinked InEmail View article References Arega SM, Knobel DL, Toka FN, Conan A. Non-specific effects of veterinary vaccines: a systematic review. Vaccine. 2022;40(11):1655–1664. https://doi.org/10.1016/j.vaccine.2021.11.034 Crossref, Google ScholarBenn CS, Amenyogbe N, Björkman A et al.. Implications of non-specific effects for testing, approving, and regulating vaccines. Drug Saf. 2023 May;46(5):439–448. https://doi.org/10.1007/s40264-023-01295-3 Crossref, Google ScholarFink F, Lipatov V, Konitzer M. Diagnoses by general practitioners: Accuracy and reliability. Int J Forecasting. 2009;25(4):784–793. https://doi.org/10.1016/j.ijforecast.2009.05.023 Crossref, Google ScholarGOV.UK. Notifications of infectious diseases (NOIDs). 2023. https://www.gov.uk/government/collections/notifications-of-infectious-diseases-noids (accessed 23 May 2023) Google ScholarJones R. Excess winter mortality (EWM) as a dynamic forensic tool: where, when, which conditions, gender, ethnicity, and age. Int J Environ Res Public Health. 2021;18(4):2161. https://doi.org/10.3390/ijerph18042161 Crossref, Google ScholarJones RP. A model to compare international hospital bed numbers, including a case study on the role of indigenous people on acute ‘occupied’ bed demand in Australian states. Int J Environ Res Public Health. 2022;19:11239. https://doi.org/10.3390/ijerph191811239 Crossref, Google ScholarJones R, Ponomarenko A. Trends in excess winter mortality (EWM) from 1900/01 to 2019/20 – evidence for a complex system of multiple long-term trends. Int J Environ Res Public Health. 2022a;19:3407. https://doi.org/10.3390/ijerph19063407 Crossref, Google ScholarJones R, Ponomarenko A. System complexity in influenza infection and vaccination: effects upon excess winter mortality. Infect Dis Rep. 2022b;14(3):287–309. https://doi.org/10.3390/idr14030035 Crossref, Google ScholarJones R, Ponomarenko A. Roles for pathogen interference in influenza vaccination, with implications to vaccine effectiveness (VE) and attribution of influenza deaths. Infect Dis Rep. 2022c;14(5):710–758. https://doi.org/10.3390/idr14050076 Crossref, Google ScholarJones RP, Ponomarenko A. Effect of age, sex, and covid-19 vaccination history on all-cause mortality: unexpected outcomes in a complex biological and social system. Preprints. 2023a;2023040248. https://doi.org/10.20944/preprints202304.0248.v1 Google ScholarJones RP, Ponomarenko A. Age profiles for SARS-CoV-2 variants in England and Wales and States of the USA (2020 to 2022): Impact on all-cause mortality. 2023b;2023050911. https://doi.org/10.20944/preprints202305.0911.v1 Google ScholarNHS Digital. Hospital Admitted Patient Care Activity - NHS Digital. 2022. https://tinyurl.com/ye22uy2k (accessed 23 May 2023) Google ScholarOffice for National Statistics. National population projections: 2020-based interim. 2022. https://tinyurl.com/55dcujed (accessed 23 May 2023) Google ScholarOffice for National Statistics. Deaths registered monthly in England and Wales. 2023. https://tinyurl.com/yaxmv92v (accessed 23 May 2023) Google ScholarWaltrald F, Lipatov V, Konitzer M. Diagnoses by general practitioners: Accuracy and reliability. Int J Forecasting. 2009;25(4):784–793. https://doi.org/10.1016/j.ijforecast.2009.05.023 Crossref, Google Scholar FiguresReferencesRelatedDetails 2 June 2023Volume 15Issue 6ISSN (print): 1759-1376ISSN (online): 2041-9457 Metrics History Published online 2 June 2023 Published in print 2 June 2023 Information© MA Healthcare LimitedPDF download

Seasonal mortality trends for hospitalised patients with acute kidney injury across England

BackgroundIncidence of acute kidney injury (AKI) is known to peak in winter months. This is likely influenced by seasonality of commonly associated acute illnesses. We set out to assess seasonal mortality trends for patients who develop AKI across the English National Health Service (NHS) and to better understand associations with patient ‘case-mix’.MethodsThe study cohort included all hospitalised adult patients in England who triggered a biochemical AKI alert in 2017. We modelled the impact of season on 30-day mortality using multivariable logistic regression; adjusting for age, sex, ethnicity, index of multiple deprivation (IMD), primary diagnosis, comorbidity (RCCI), elective/emergency admission, peak AKI stage and community/hospital acquired AKI. Seasonal odds ratios for AKI mortality were then calculated and compared across individual NHS hospital trusts.ResultsThe crude 30-day mortality for hospitalised AKI patients was 33% higher in winter compared to summer. Case-mix adjustment for a wide range of clinical and demographic factors did not fully explain excess winter mortality. The adjusted odds ratio of patients dying in winter vs. summer was 1.25 (1.22–1.29), this was higher than for Autumn and Spring vs. Summer, 1.09 (1.06–1.12) and 1.07 (1.04–1.11) respectively and varied across different NHS trusts (9 out of 90 centres outliers).ConclusionWe have demonstrated an excess winter mortality risk for hospitalised patients with AKI across the English NHS, which could not be fully explained by seasonal variation in patient case-mix. Whilst the explanation for worse winter outcomes is not clear, unaccounted differences including ‘winter-pressures’ merit further investigation.

Policy prescriptions to address energy and transport poverty in the United Kingdom

Tens of millions of households across Europe struggle to afford adequate electricity and heating services and reliable transportation, while recent high fuel prices could lead to an increase in excess winter deaths. Tackling energy and transport poverty is thus of paramount policy importance. Here we document the drivers and lived experiences of energy and transport poverty in the United Kingdom, based on public focus groups and expert interviews. We find a set of policies that resonate with both expert planners and members of the public, implying they have a level of political and social acceptability that other measures may be lacking, notably: mandatory landlord energy efficiency upgrades, increasing the extent of financial assistance to households, cheaper (or even free) bus and train fares and restarting and expanding bus services. We buttress these findings with further suggestions for energy and transport system redesign that better meets emerging principles of energy and social justice.

S-01-3: SMART WELLNESS HOUSING AND BLOOD PRESSURE CONTROL

Objective: Mortality due to cardiovascular diseases (CVDs) rises sharply in winter, a phenomenon known as excess winter mortality. It is partially explained by cold exposure induced hypertension. Nevertheless, existing countermeasures for the prevention of hypertension and CVDs place emphasis only on improving lifestyle habits. Improving life environment has attracted attention recently because people spend 60–70% of their time at home. Therefore, we aimed to quantitatively evaluate the relationship between housing thermal environment and blood pressure (BP) in a real-world setting. Design and method: We conducted a nationwide prospective intervention study named the Smart Wellness Housing survey in Japan, as a nonrandomized controlled trial. The intervention was the thermal insulation retrofitting of homes. Participants were recruited by construction companies throughout all 47 prefectures of Japan. Home BP and indoor temperature were measured for 2 weeks before and after the intervention in winter (November-March) of FY 2014 to 2019. Results: Cross-sectional analyses before intervention involving about 2900 participants (1840 households) showed that systolic blood pressure (SBP) in the morning had significantly higher sensitivity to changes in indoor temperature (8.2 mmHg increase/10°C decrease) than that in the evening (6.5 mmHg increase/10°C decrease) in participants aged 57 years (mean age in this survey). Interaction terms between age/women and indoor temperature were significant, indicating that SBP in older residents and women was vulnerable to indoor temperature change. The association between BP variability and indoor temperature instability was also analyzed using the morning-evening (ME) difference as an index of diurnal variability and the standard deviation (SD) of 2-week data as an index of day-by-day variability. The analyses showed that the ME difference in indoor temperature was closely correlated with the ME difference in SBP (0.85 mmHg/°C). The SD of indoor temperature was also associated with the SD of SBP (0.61 mmHg/°C). In the comparison of before and after intervention, insulation retrofitting significantly reduced morning SBP by 3.1 mmHg. In addition, there was heterogeneity in the effect of insulation retrofitting on morning SBP in hypertensive patients compared with normotensive occupants (-7.7 versus -2.2 mmHg). Conclusions: Hypertension might be not only lifestyle diseases but also life-environment diseases. Residents should keep the indoor temperature high to reduce BP level and keep it stable to reduce BP variability through strategies such as installing high thermal insulation. We expect that these results will be useful to prevent excess winter mortality due to CVDs.

The adverse effect of ambient temperature on respiratory deaths in a high population density area: the case of Malta

BackgroundThe effect of ambient temperature on respiratory mortality has been consistently observed throughout the world under different climate change scenarios. Countries experiencing greater inter–annual variability in winter temperatures (and may not be lowest winter temperatures) have greater excess winter mortality compared to countries with colder winters. This study investigates the association between temperature and respiratory deaths in Malta which has one of the highest population densities in the world with a climate that is very hot in summer and mild in winter.MethodsDaily number of respiratory deaths (7679 deaths) and meteorological data (daily average temperature, daily average humidity) were obtained from January 1992 to December 2017. The hot and cold effects were estimated at different temperatures using distributed lag non-linear models (DLNM) with a Poisson distribution, controlling for time trend, relative humidity and holidays. The reference temperature (MMT) for the minimum response-exposure relationship was estimated and the harvesting effects of daily temperature (0–27 lag days) were investigated for daily respiratory mortality. Effects were also explored for different age groups, gender and time periods.ResultsCooler temperatures (8–15 °C) were significantly related to higher respiratory mortality. At 8.9 °C (1st percentile), the overall effect of daily mean temperature was related to respiratory deaths (RR 2.24, 95%CI 1.10–4.54). These effects were also found for males (95%CI 1.06–7.77) and males across different age groups (Males Over 65 years: RR 4.85, 95%CI 2.02–11.63 vs Males between 16 and 64 years: RR 5.00, 95%CI 2.08–12.03) but not for females. Interestingly, colder temperatures were related to respiratory deaths in the earliest time period (1992–2000), however, no strong cold effect was observed for later periods (2000–2017). In contrast, no heat effect was observed during the study period and across other groups.ConclusionsThe higher risk for cold-related respiratory mortality observed in this study could be due to greater inter-annual variability in winter temperatures which needs further exploration after adjusting for potential physical and socio-demographic attributes. The study provides useful evidence for policymakers to improve local warning systems, adaptation, and intervention strategies to reduce the impact of cold temperatures.

Cold homes and mental health harm: Evidence from the UK Household Longitudinal Study

Cold homes are associated with a range of serious health conditions as well as excess winter mortality. Despite a comparatively mild climate cold homes are a significant problem in the UK, with a recent estimate finding that over one-quarter of low-income households had been unable to adequately heat their home in winter 2022. The magnitude of cold housing in a country that benefits from a mild climate indicates indifference towards, or acceptance of, a significant minority of people living in inadequate conditions on the part of policy makers. Cold homes are therefore a source of social harm. Recent changes to the household energy price cap, the rising cost of living, the ongoing effects of the benefit cap, and below inflation uprating to social security benefits is likely to greatly exacerbate this issue. In this research we use data from the UK Household Longitudinal Study to explore whether living in a cold home causes mental health harm. We control for mental distress and housing temperature on entry to the survey in order to account for the potentially bi-directional relationship. Multilevel discrete-time event history models show that the transition into living in a home that is not suitably warm is associated with nearly double the odds of experiencing severe mental distress for those who had no mental distress at the beginning of the survey; and over three times the odds of severe mental distress for those previously on the borderline of severe mental distress. These results show the significant costs of failing to ensure that people are able to live in homes in which they are able to live comfortably by even the most basic standards. These costs will be felt not just individually, but also more broadly in terms of increased health spending and reduced working.

Early winter barium excess in the southern Indian Ocean as an annual remineralisation proxy (GEOTRACES GIPr07 cruise)

Abstract. The Southern Ocean (SO) is of global importance to the carbon cycle, and processes such as mesopelagic remineralisation that impact the efficiency of the biological carbon pump in this region need to be better constrained. During this study early austral winter barium excess (Baxs) concentrations were measured for the first time, along 30∘ E in the southern Indian Ocean. Winter Baxs concentrations of 59 to 684 pmol L−1 were comparable to those observed throughout other seasons. The expected decline of the mesopelagic Baxs signal to background values during winter was not observed, supporting the hypothesis that this remineralisation proxy likely has a longer timescale than previously reported. A compilation of available SO mesopelagic Baxs data, including data from this study, shows an accumulation rate of ∼0.9 µmol m−2 d−1 from September to July that correlates with temporally integrated remotely sensed primary productivity (PP) throughout the SO from data spanning ∼20 years, advocating for a possible annual timescale of this proxy. The percentage of mesopelagic particulate organic carbon (POC) remineralisation as calculated from estimated POC remineralisation fluxes over integrated remotely sensed PP was ∼2-fold higher south of the polar front (19 ± 15 %, n=39) than north of the polar front (10 ± 10 %, n=29), revealing the higher surface carbon export efficiency further south. By linking integrated remotely sensed PP to mesopelagic Baxs stock, we could obtain better estimates of carbon export and remineralisation signals within the SO on annual and basin scales.

Environmental and socioeconomic determinants of neonatal mortality in a northern Italian city in the early nineteenth century

The research explores the effects of the environment on neonatal mortality in the early nineteenth century, controlling for social and economic factors. Individual data, relative to the resident population of Udine, a city in northeastern Italy, under French domination (1806–1815) have been used. The information collected regards births and deaths within the first month of life and is taken from the Napoleonic civil registers. The spatial distribution of some data within the urban area, heating in the houses where children were born or died, and a time series of temperature levels and corn prices are taken into account. The methodological approach adopted is based on logistic regression models and discrete-time event history analysis. The results point to excess winter neonatal mortality. Neonatal mortality was higher in peripheral areas of the city and in heated houses. A positive relationship between mortality and lower temperatures and corn prices has been found. As to socioeconomic status, peasant families and those of the upper class showed, respectively, the lowest and the highest mortality levels. This was arguably the result of the adoption of different breastfeeding practices.

Early winter barium excess in the Southern Indian Ocean as an annual remineralisation proxy (GEOTRACES GIPr07 cruise)

Early winter barium excess in the Southern Indian Ocean as an annual remineralisation proxy (GEOTRACES GIPr07 cruise)

An improved definition of official excess winter mortality statistics as the basis for detailed analysis and monitoring

In official statistics, excess winter mortality, the number of additional deaths in a winter period, is typically defined as the difference between mortality in a winter period relative to the nonwinter periods before and after. We note two limitations of this approach: (1) the data for the period after winter is available only later, so estimates of excess winter mortality are not timely; (2) unusually high or low numbers of deaths in the non-winter periods can affect estimates. We propose an alternative statistic based on the application of standard seasonal adjustment procedures. We compare the approaches and present some illustrative analyses. The new statistic provides a more objective and timely official series, but is susceptible to revisions, which are shown to be small in practice. We recommend it as the basis of more detailed monitoring and modelling.

System Complexity in Influenza Infection and Vaccination: Effects upon Excess Winter Mortality.

Unexpected outcomes are usually associated with interventions in complex systems. Excess winter mortality (EWM) is a measure of the net effect of all competing forces operating each winter, including influenza(s) and non-influenza pathogens. In this study over 2400 data points from 97 countries are used to look at the net effect of influenza vaccination rates in the elderly aged 65+ against excess winter mortality (EWM) each year from the winter of 1980/81 through to 2019/20. The observed international net effect of influenza vaccination ranges from a 7.8% reduction in EWM estimated at 100% elderly vaccination for the winter of 1989/90 down to a 9.3% increase in EWM for the winter of 2018/19. The average was only a 0.3% reduction in EWM for a 100% vaccinated elderly population. Such outcomes do not contradict the known protective effect of influenza vaccination against influenza mortality per se—they merely indicate that multiple complex interactions lie behind the observed net effect against all-causes (including all pathogen causes) of winter mortality. This range from net benefit to net disbenefit is proposed to arise from system complexity which includes environmental conditions (weather, solar cycles), the antigenic distance between constantly emerging circulating influenza clades and the influenza vaccine makeup, vaccination timing, pathogen interference, and human immune diversity (including individual history of host-virus, host-antigen interactions and immunosenescence) all interacting to give the observed outcomes each year. We propose that a narrow focus on influenza vaccine effectiveness misses the far wider complexity of winter mortality. Influenza vaccines may need to be formulated in different ways, and perhaps administered over a shorter timeframe to avoid the unanticipated adverse net outcomes seen in around 40% of years.

Trends in Excess Winter Mortality (EWM) from 1900/01 to 2019/20-Evidence for a Complex System of Multiple Long-Term Trends.

Trends in excess winter mortality (EWM) were investigated from the winter of 1900/01 to 2019/20. During the 1918–1919 Spanish flu epidemic a maximum EWM of 100% was observed in both Denmark and the USA, and 131% in Sweden. During the Spanish flu epidemic in the USA 70% of excess winter deaths were coded to influenza. EWM steadily declined from the Spanish flu peak to a minimum around the 1960s to 1980s. This decline was accompanied by a shift in deaths away from the winter and spring, and the EWM calculation shifted from a maximum around April to June in the early 1900s to around March since the late 1960s. EWM has a good correlation with the number of estimated influenza deaths, but in this context influenza pandemics after the Spanish flu only had an EWM equivalent to that for seasonal influenza. This was confirmed for a large sample of world countries for the three pandemics occurring after 1960. Using data from 1980 onward the effect of influenza vaccination on EWM were examined using a large international dataset. No effect of increasing influenza vaccination could be discerned; however, there are multiple competing forces influencing EWM which will obscure any underlying trend, e.g., increasing age at death, multimorbidity, dementia, polypharmacy, diabetes, and obesity—all of which either interfere with vaccine effectiveness or are risk factors for influenza death. After adjusting the trend in EWM in the USA influenza vaccination can be seen to be masking higher winter deaths among a high morbidity US population. Adjusting for the effect of increasing obesity counteracted some of the observed increase in EWM seen in the USA. Winter deaths are clearly the outcome of a complex system of competing long-term trends.

Thermal comfort in naturally ventilated dwellings in the central Mexican plateau

A third of Mexico's population (35 M people) lacks decent housing. Current efforts to improve housing focus on structural strength and security rather than thermal comfort. However, as 59% of the population earns less than the median income, the building itself must provide adequate internal temperatures, i.e., the range between the minimum temperature suggested by WHO of 18 °C, and the maximum temperatures suggested by the CIBSE TM59:2017 criteria. Despite the perception of being a “warm” country, 38% of the Mexican population lives in places where the external temperatures often drop to 0 °C in winter falling to −6 °C during seasonal cold fronts. This is worrying, as a lack of adequate protection from low indoor temperatures is associated with high excess winter mortality rates. Hence, we undertake one of the first Class-II thermal comfort studies in a cold climate in Mexican homes. For eleven months, hourly indoor environmental and occupancy data, complemented with language-localised bi-monthly thermal comfort surveys, were matched against the Adaptive and PMV thermal comfort models. We find that only 42% of the living room occupied hours were within acceptability ranges, dropping to 22% in winter. Finally, we find that current strategies for achieving homeostatic heat balance are garment based (i.e., extra blankets or clothing), in addition to electric heaters to a lesser extent. Hence, we find that Mexican houses are presently not capable of providing adequate internal thermal environments during cold periods, suggesting the need for an extensive insulation programme.

Effects of indoor and outdoor temperatures on blood pressure and central hemodynamics in a wintertime panel of peri-urban Chinese adults

BACKGROUND AND AIM: Excess wintertime cardiovascular mortality has been observed in populations globally and is partly attributed to cold-induced elevated blood pressure (BP). An inverse relationship between outdoor temperature and BP is well documented. The influence of indoor environmental conditions (e.g., heating, insulation) and indoor temperature on BP is less clear. We examined the effects of indoor and outdoor temperature on wintertime BP and central hemodynamics among older adults in peri-urban Beijing, China. METHODS: We enrolled 1,285 older adults into a panel study conducted in two winter seasons (2018-19 and 2019-2020). Staff traveled to participant homes to administer a questionnaire and measure their brachial and central systolic and diastolic BPs, pulse pressures, and pulse pressure amplification. Indoor temperature was measured within the 5-minutes prior to BP measurements for all participants and 12-month indoor temperature measurements were obtained in a 37% (1st season) and 32% (2nd season) random subsample. Village-level outdoor temperature was estimated from regional meteorological stations. Multivariable mixed-effects regression models were used to estimate the within- and between-individual effects of indoor and outdoor temperature on BP, allowing for effect measure modification. RESULTS:Indoor and outdoor winter temperatures ranged from 0.0 to 28.0˚C and -14.3 to 6.4˚C, respectively. Those in colder homes had a lower wealth score and less home insulation. We observed an inverse linear relationship between indoor temperature and BP (mmHg per 1˚C increase in temperature: −0.4 to −0.5 systolic, −0.3 diastolic, and −0.2 pulse pressure). We found little evidence of any effect of outdoor temperature with BP, or that outdoor temperature modified the effect of indoor temperature. CONCLUSIONS:We found an inverse association between indoor temperature and BP, but no relationship of BP with outdoor temperature. This suggests a stronger effect on BP of indoor compared to outdoor temperature. Improving insulation and household heating may help lower BP and prevent excess winter mortality. KEYWORDS: Cardiovascular diseases, Epidemiology, Socio-economic factors, Temperature

Excess mortality at Christmas due to cardiovascular disease in the HUNT study prospective population-based cohort in Norway

BackgroundAlthough it is known that winter inclusive of the Christmas holiday period is associated with an increased risk of dying compared to other times of the year, very few studies have specifically examined this phenomenon within a population cohort subject to baseline profiling and prospective follow-up. In such a cohort, we sought to determine the specific characteristics of mortality occuring during the Christmas holidays.MethodsBaseline profiling and outcome data were derived from a prospective population-based cohort with longitudinal follow-up in Central Norway - the Trøndelag Health (HUNT) Study. From 1984 to 1986, 88% of the target population comprising 39,273 men and 40,353 women aged 48 ± 18 and 50 ± 18 years, respectively, were profiled. We examined the long-term pattern of mortality to determine the number of excess (all-cause and cause-specific) deaths that occurred during winter overall and, more specifically, the Christmas holidays.ResultsDuring 33.5 (IQR 17.1–34.4) years follow-up, 19,879 (50.7%) men and 19,316 (49.3%) women died at age-adjusted rate of 5.3 and 4.6 deaths per 1000/annum, respectively. Overall, 1540 (95% CI 43–45 deaths/season) more all-cause deaths occurred in winter (December to February) versus summer (June to August), with 735 (95% CI 20–22 deaths per season) of these cardiovascular-related. December 25th–27th was the deadliest 3-day period of the year; being associated with 138 (95% CI 96–147) and 102 (95% CI 72–132) excess all-cause and cardiovascular-related deaths, respectively. Accordingly, compared to 1st–21st December (equivalent winter conditions), the incidence rate ratio of all-cause mortality increased to 1.22 (95% CI 1.16–1.27) and 1.17 (95% 1.11–1.22) in men and women, respectively, during the next 21 days (Christmas/New Year holidays). All observed differences were highly significant (P < 0.001). A less pronounced pattern of mortality due to respiratory illnesses (but not cancer) was also observed.ConclusionBeyond a broader pattern of seasonally-linked mortality characterised by excess winter deaths, the deadliest time of year in Central Norway coincides with the Christmas holidays. During this time, the pattern and frequency of cardiovascular-related mortality changes markedly; contrasting with a more stable pattern of cancer-related mortality. Pending confirmation in other populations and climates, further research to determine if these excess deaths are preventable is warranted.