Pedestrian wintertime slip and fall injuries-effectiveness of weather warning service in prevention.

BACKGROUND AND AIM: In climates with wintry conditions, slip and fall injuries of pedestrians during wintertime can result in high healthcare and societal costs. The aim of this study was to evaluate the effectiveness of early warnings about slipperiness in preventing such injuries in Finland. Since 2004, the Finnish Meteorological Institute (FMI) has been providing a weather service for pedestrians, which has been developed continuously over time. DATA AND METHODS: Time series of pedestrian slip and fall injuries in commuting on foot in the 19 regions of Finland in 2005-2022 was obtained from the Finnish Workers' Compensation Center and analysed for trends. We also analysed daily warnings about slippery sidewalks from the FMI archives for the period 2011-2022. To identify steps in the service chain that require improvement, we conducted a weather service chain analysis (WSCA) based on a slip and fall accident storyline. RESULTS: There was no significant trend in the number of slipping injuries during the study period. The exposure of the Finnish population to slippery conditions varies according to the climate of the region and characteristics of the winters. We found that the responses of the users of the warning information may be inadequate. CONCLUSIONS: Changes in the behaviour of individuals and more efficient winter maintenance of sidewalks are required. Furthermore, it is necessary to promote the role and safety of walking in the planning of traffic systems and urban planning. Further improvements to the pedestrian weather service are needed as well.

Recognition of climate-related risks for prehospital emergency medical service and emergency department in Finland - A Delphi study.

BACKGROUND: Emergency departments (ED) and prehospital emergency medical services (EMS) will experience new or increasing challenges due to the changing climate. The aims of this study was to add knowledge about these challenges in Finland and to help EMS and ED operators to prepare for the effects of climate change. METHODS: A two-round Delphi study was conducted. Ten participants expressed their views of climate change-related challenges currently and in the future, and how to prepare for challenges ahead. First-round questions based on the literature search about the climate-related impacts on EMS and ED. The stage one data was analysed by thematic analysis, which generated the second-round survey where the probability of the statements was estimated. RESULTS: Various climate change-related challenges were recognized such as negative health impacts, the increased workload, difficulties with the EMS operations and problems with the functions of society. Preparation of action plans was considered important in case for incidents and emergencies. CONCLUSION: The study indicated that climate change may cause various challenges for EMS and ED in Finland. To meet the future challenges, it is important to identify potential future risks and create plans to manage them. Further studies are needed to create climate resilient healthcare systems.

Effect of cold winters on the risk of new asthma: a case-crossover study in Finland.

BACKGROUND: Cold weather increases respiratory symptoms and provokes exacerbations of asthma, but there are no previous studies on its role in the aetiology of asthma. OBJECTIVE: We tested the hypothesis that a cold winter increases the risk of developing asthma during the following 1 to 2 years. METHODS: We conducted a case-crossover study of 315 newly diagnosed cases of asthma from the population-based Espoo Cohort Study from birth to the age of 27 years. The hazard period constituted 3 winter months preceding the onset of asthma and bidirectional reference periods of 1 year before hazard period and 1 year after onset of asthma. Exposure constituted average ambient temperature during the winter months of December, January and February. The outcome of interest was new doctor-diagnosed asthma. The measure of effect was OR of asthma estimated by conditional logistic regression analysis. RESULTS: The average winter temperature for the study period from winter 1983 to 2010 was -4.4°C (range -10.7 to 0.4). A 1°C decrease in the average winter temperature predicted a 7% increase in the risk of new asthma (OR=1.07, 95% CI 1.02 to 1.13). A cold winter with an average temperature below the climate normal value (-4.5°C; period 1981-2010) increased the risk of new asthma by 41% during the following year (OR: 1.41; 95% CI 1.04 to 1.90). CONCLUSIONS: This case-crossover study provides original evidence that a cold winter with below normal average temperatures increases the risk of developing new asthma during the following 1 to 2 years.

Long-term residential sunlight exposure associated with cognitive function among adults residing in Finland.

While sunlight may influence cognitive function through several pathways, associations of residential sunlight exposure with cognitive function are not well known. We evaluated associations of long-term residential sunlight exposure with cognitive function among a representative cohort of 1838 Finnish adults residing in Finland who underwent comprehensive cognitive assessment in midlife. We linked daily recordings of global solar radiation to study participants using residential information and calculated the average daily residential exposure to sunlight for four exposure time intervals: 2 months, 1 year, 2 years and 5 years prior to the date of the cognition assessment. Associations of the residential sunlight exposure with cognitive function were assessed using linear regression analyses adjusting for season, sex, age, and individual- and neighborhood-level socioeconomic characteristics. Greater average residential sunlight exposure over 2 and 5 years prior to the cognitive function assessment was associated with better global cognitive function (b = 0.13, 95% CI = 0.01, 0.25; b = 0.17, 95% CI = 0.05, 0.29, per 1 MJ/m2 difference in sunlight exposure), while no associations with global cognitive function were observed at shorter exposure time intervals. In domain-specific analyses, greater residential exposure to sunlight over 1, 2 and 5 years prior to the cognitive function assessment was associated with better performance on new learning and visual memory (b = 0.10, 95% CI = 0.00, 0.20; b = 0.16, 95% CI = 0.04, 0.28; b = 0.19, 95% CI = 0.08, 0.31) and sustained attention (b = 0.15, 95% CI = 0.05, 0.25; b = 0.18, 95% CI = 0.06, 0.30; b = 0.17, 95% CI = 0.05, 0.29), but worse performance on reaction time (b = - 0.12, 95% CI = - 0.22, - 0.02; b = -0.15, 95% CI = - 0.28, - 0.02; b = - 0.18, 95% CI = - 0.30, - 0.05). Residential sunlight exposure was not associated with executive function. These findings suggest long-term residential sunlight exposure may be an environmental factor influencing cognitive function among a cognitively healthy cohort residing in Northern Europe. Further studies in populations residing in different geographical locations are needed.

Impact of Selected Meteorological Factors on COVID-19 Incidence in Southern Finland during 2020-2021.

We modelled the impact of selected meteorological factors on the daily number of new cases of the coronavirus disease 2019 (COVID-19) at the Hospital District of Helsinki and Uusimaa in southern Finland from August 2020 until May 2021. We applied a DLNM (distributed lag non-linear model) with and without various environmental and non-environmental confounding factors. The relationship between the daily mean temperature or absolute humidity and COVID-19 morbidity shows a non-linear dependency, with increased incidence of COVID-19 at low temperatures between 0 to -10 °C or at low absolute humidity (AH) values below 6 g/m3. However, the outcomes need to be interpreted with caution, because the associations found may be valid only for the study period in 2020-2021. Longer study periods are needed to investigate whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has a seasonal pattern similar such as influenza and other viral respiratory infections. The influence of other non-environmental factors such as various mitigation measures are important to consider in future studies. Knowledge about associations between meteorological factors and COVID-19 can be useful information for policy makers and the education and health sector to predict and prepare for epidemic waves in the coming winters.

Climatic exposures in childhood and the risk of schizophrenia from childhood to early adulthood.

BACKGROUND: Season of birth is a risk factor of schizophrenia, and it is possible that cumulative exposure to climatic factors during childhood affects the risk of schizophrenia. We conducted a cohort study among 365,482 persons born in Finland in 1990-1995 to examine associations of 10-year cumulative exposure to global solar radiation and ambient temperature in childhood with schizophrenia. METHODS: Data on schizophrenia diagnoses and sociodemographic factors from the Finnish population register and health care register were linked to daily meteorological data using residential information. The study population was followed from age 10 until the first schizophrenia diagnosis, death, emigration or December 31, 2017, whichever came first. Hazard ratios (HR) for the risk of schizophrenia were estimated using Cox proportional hazards model. RESULTS: Compared to the lowest quintile of global solar radiation or ambient temperature, growing up in the second highest quintile (Q4) was associated with greater risk of schizophrenia. These hazard ratios were attenuated after adjustment for parental mental disorder, parental education, parental income, area-level socioeconomic characteristics and urbanicity (HR = 1.29, 95 % CI 1.06-1.58 for radiation; HR = 1.24, 95 % CI, 1.02-1.52 for temperature). Continuous linear terms evaluated in secondary models suggested a greater risk of schizophrenia at greater childhood exposure to global radiation and ambient temperature, but these associations did not remain in fully adjusted models. CONCLUSIONS: We found no consistent evidence that cumulative exposure to sunlight and ambient temperature in childhood is associated with the risk of developing schizophrenia. Studies in other populations residing in different latitudes are needed.

Associations of long-term solar insolation with specific depressive symptoms: Evidence from a prospective cohort study.

Evidence suggests that sunlight counteracts depression, but the associations of long-term sunlight exposure with specific symptoms of depression are not well known. We evaluated symptom-specific associations of average 1-year solar insolation with DSM-5 depressive symptoms in a representative cohort of Finnish adults. The sample included 1,845 participants from the Cardiovascular Risk in Young Finns Study with data on DSM-5 depressive symptoms, place of residence and covariates. Daily recordings of global solar radiation were obtained from the Finnish Meteorological Institute. Each participant's residential zip code on each day one year prior to the assessment of depressive symptoms was linked to the solar radiation data, and 1-year average daily solar insolation was calculated. Associations of the average 1-year solar insolation with depressive symptoms were assessed with linear and logistic regression analyses adjusting for season, sex, age, as well as individual- and neighborhood-level socioeconomic characteristics. Average daily solar insolation over one year prior to the depressive symptom assessment was not associated with the total number of depressive symptoms reported by participants. In symptom-specific analyses, participants exposed to higher levels of solar insolation in their residential neighborhood were less likely to report suicidal thought (OR = 0.61, 95% CI, 0.39-0.94), and more likely to report changes in appetite (OR = 1.24, 95% CI, 1.00-1.54), changes in sleep (OR = 1.30, 95% CI, 1.06-1.59) and feelings of worthlessness/guilt (OR = 1.33, 95% CI = 1.07-1.65). These findings suggest that solar insolation may contribute to symptom-specific differences in depression. Studies in other populations residing in different geographical locations are needed.

Long-term cumulative light exposure from the natural environment and sleep: A cohort study.

We analysed (A) the association of short-term as well as long-term cumulative exposure to natural light, and (B) the association of detailed temporal patterns of natural light exposure history with three indicators of sleep: sleep duration, sleep problems, and diurnal preference. Data (N = 1,962; 55% women; mean age 41.4 years) were from the prospective Young Finns Study, which we linked to daily meteorological data on each participant's neighbourhood natural light exposure using residential postal codes. Sleep outcomes were self-reported in 2011. We first examined associations of the sleep outcomes with cumulative light exposure of 5-year, 2-year, 1-year, and 2-month periods prior to the sleep assessment using linear and Poisson regression models adjusting for potential confounders. We then used a data-driven time series approach to detect clusters of participants with different light exposure histories and assessed the associations of these clusters with the sleep outcomes using linear and Poisson regression analyses. A greater cumulative light exposure over ≥1 year was associated with a shorter sleep duration (ß = -0.10, 95% confidence interval [CI] -0.15 to -0.04), more sleep problems (incident rate ratio [IRR] 1.04, 95% CI 1.0-1.07) and diurnal preference towards eveningness (ß = -0.09, 95% CI -0.14 to -0.03). The data-driven exposure pattern of "slowly increasing" light exposure was associated with fewer overall sleep problems (IRR 0.93, 95% CI 0.88-0.98) compared to a "recently declining" light exposure group representing the "average-exposure" group. These findings suggest that living in an area with relatively more intense light exposure for a longer period of time influences sleep.

Seasonal Variation in Generic and Disease-Specific Health-Related Quality of Life in Rhinologic Patients in Southern Finland.

BACKGROUND: Seasonal variation in exacerbations, hospitalisations, and mortality statistics has been reported for some diseases. To our knowledge, however, no published studies exist on the seasonality of health-related quality of life (HRQoL) amongst rhinologic patients. AIMS/OBJECTIVES: This study, therefore, aimed to investigate the possible seasonal variation in rhinologic patients' HRQoL using the rhinologic disease-specific Sino-Nasal Outcome Test-22 (SNOT-22) and the generic 15D HRQoL instrument. MATERIAL AND METHODS: We enrolled unselected adult rhinologic patients requiring specialist care at the Helsinki University Hospital in this cross-sectional, questionnaire-based prospective study during four seasons: February (winter), May (spring), August (summer), and November (autumn). Patients received SNOT-22 and 15D questionnaires via post. The Finnish Meteorological Institute supplied climate data from these months. RESULTS: SNOT-22 and 15D data were available for 301 and 298 patients, respectively. We found no statistically significant differences (p = 0.948) between the mean monthly 15D scores or mean SNOT-22 scales. Furthermore, the mean SNOT-22 subscales did not differ between the monthly study periods. CONCLUSIONS AND SIGNIFICANCE: Our study shows that seasonality did not impact rhinologic patients' SNOT-22 or 15D HRQoL scores. Thus, these questionnaires can be used for follow-up amongst rhinologic patients regardless of season.

Campylobacter infections expected to increase due to climate change in Northern Europe.

Global climate change is predicted to alter precipitation and temperature patterns across the world, affecting a range of infectious diseases and particularly foodborne infections such as Campylobacter. In this study, we used national surveillance data to analyse the relationship between climate and campylobacteriosis in Denmark, Finland, Norway and Sweden and estimate the impact of climate changes on future disease patterns. We show that Campylobacter incidences are linked to increases in temperature and especially precipitation in the week before illness, suggesting a non-food transmission route. These four countries may experience a doubling of Campylobacter cases by the end of the 2080s, corresponding to around 6,000 excess cases per year caused only by climate changes. Considering the strong worldwide burden of campylobacteriosis, it is important to assess local and regional impacts of climate change in order to initiate timely public health management and adaptation strategies.

Regional Assessment of Temperature-Related Mortality in Finland.

The aim of this study was to assess regional differences in temperature-mortality relationships across 21 hospital districts in Finland. The temperature dependence of the daily number of all-cause, all-aged deaths during 2000-2014 was studied in each hospital district by using daily mean temperatures, spatially averaged across each hospital district, to describe exposure to heat stress and cold stress. The relationships were modelled using distributed lag non-linear models (DLNM). In a simple model version, no delayed impacts of heat and cold on mortality were taken into account, whereas a more complex version included delayed impacts up to 25 days. A meta-analysis with selected climatic and sociodemographic covariates was conducted to study differences in the relationships between hospital districts. A pooled mortality-temperature relationship was produced to describe the average relationship in Finland. The simple DLNM model version without lag gave U-shaped dependencies of mortality on temperature almost without exception. The outputs of the model version with a 25-day lag were also U-shaped in most hospital districts. According to the meta-analysis, the differences in the temperature-mortality relationships between hospital districts were not statistically significant on the absolute temperature scale, meaning that the pooled mortality-temperature relationship can be applied to the whole country. However, on a relative temperature scale, heterogeneity was found, and the meta-regression suggested that morbidity index and population in the hospital districts might explain some of this heterogeneity. The pooled estimate for the relative risk (RR) of mortality at a daily mean temperature of 24 °C was 1.16 (95% CI 1.12-1.20) with reference at 14 °C, which is the minimum mortality temperature (MMT) of the pooled relationship. On the cold side, the RR at a daily mean temperature of -20 °C was 1.14 (95% CI 1.12-1.16). On a relative scale of daily mean temperature, the MMT was found at the 79th percentile.

Biometeorological Assessment of Mortality Related to Extreme Temperatures in Helsinki Region, Finland, 1972-2014.

Climate change is expected to increase heat-related and decrease cold-related mortality. The extent of acclimatization of the population to gradually-changing thermal conditions is not well understood. We aimed to define the relationship between mortality and temperature extremes in different age groups in the Helsinki-Uusimaa hospital district in Southern Finland, and changes in sensitivity of the population to temperature extremes over the period of 1972-2014. Time series of mortality were made stationary with a method that utilizes 365-day Gaussian smoothing, removes trends and seasonality, and gives relative mortality as the result. We used generalized additive models to examine the association of relative mortality to physiologically equivalent temperature (PET) and to air temperature in the 43-year study period and in two 21-year long sub-periods (1972-1992 and 1994-2014). We calculated the mean values of relative mortality in percentile-based categories of thermal indices. Relative mortality increases more in the hot than in the cold tail of the thermal distribution. The increase is strongest among those aged 75 years and older, but is somewhat elevated even among those younger than 65 years. Above the 99th percentile of the PET distribution, the all-aged relative mortality decreased in time from 18.3 to 8.6%. Among those ≥75 years old, the decrease in relative mortality between the sub-periods were found to be above the 90th percentile. The dependence of relative mortality on cold extremes was negligible, except among those ≥75 years old, in the latter period. Thus, heat-related mortality is also remarkable in Finland, but the sensitivity to heat stress has decreased over the decades.

Supracondylar humerus fractures in children: the effect of weather conditions on their risk.

INTRODUCTION: Supracondylar humerus fractures are the most common fractures of the elbow in children. Many environmental factors such as weather conditions may affect the risk of these fractures. The purpose of the study was to analyze the effect of weather conditions (temperature, rainfall, wind) on fracture risk in children <16 years of age during the extended summer time period with the absence of snow cover. MATERIALS AND METHODS: All children <16 years of age with an outdoor supracondylar humerus fracture between May 1 and September 30 in a defined geographical area during the decade of 2000-2009 were included. Daily meteorological recordings for altogether 1526 study days were reviewed from the national weather service and the association of weather conditions and fractures were analyzed. RESULTS: A majority (79.7%, N = 181) of the fractures occurred on dry days versus rainy days (20.3%) (P = 0.011), and risk of a fracture was 3.5-fold higher on dry days as compared with rainy days (crude OR 3.5, 3.41-3.59, P < 0.001). The weather was warm, instead of cool or hot, when the majority of the fractures (N = 147, 64.8%) occurred (P = 0.008): Warm temperatures (15-24.9 °C) increased the fracture risk 2.6-fold (crude OR 2.64, 2.59-2.70, P < 0.001), compared with cool (<15 °C) days. The fracture incidence did not change according to the wind speed (P = 0.171). The findings were similar through the school term and summer vacation. CONCLUSION: Dry and warm weather conditions increase the risk of outdoor supracondylar humerus fractures in children during the time period with the absence of snow cover.

Local daily temperatures, thermal seasons, and suicide rates in Finland from 1974 to 2010.

OBJECTIVES: Suicide peaks in late spring and October are still seen in Finland among many countries. Weather factors have been suggested as explanations for these peaks, although with inconsistent results. Since the exact timing of these peaks varies each year, the length of daylight and changes in it seem inadequate as an explanation. We hypothesized that ambient temperature and the timing of thermal seasons might associate with suicide rate. METHODS: Suicide rates from three areas across Finland (N = 10,802) were analyzed with Poisson regression in six different models against variables calculated from the local ambient daily temperature, diurnal temperature range, and the duration from the onset of thermal seasons. Separate models for men and women were constructed. RESULTS: The temperature change over 5 days associated with the suicide rate of men in Helsinki region, or in other words, the lower the suicide rate was, the higher the temperature decrease had been. For women, the results were more inconsistent. CONCLUSIONS: Our study is in line with some earlier studies which imply that impairment of thermoregulation might exist among suicide victims.

Population-based research on the relationship between summer weather and paediatric forearm shaft fractures.

BACKGROUND: Paediatric forearm shaft fractures show an increasing incidence. The predictive factors of these fractures are not fully understood. Summer weather is suggested to have an effect on the risk of children's fractures. We studied the effect of rainfall, temperature and wind on paediatric forearm shaft fractures in summer. METHODS: All 148 children's forearm shaft fractures in the geographic catchment district during the summer months in 1997-2009 were included. There were 1989 days in the study period. Daily meteorological readings captured the maximum daytime temperature, precipitation and wind speed. The direct daily association between fractures (yes/no) and different weather conditions was analysed in this population-based study. RESULTS: The risk of forearm shaft fracture was 50% higher on dry days compared to rainy days (P=0.038). Temperature and wind speed had no statistically significant effect on fractures. CONCLUSIONS: The results give support for the presumption by the general public and professionals that summer weather affects children's fractures. A 1.5-fold increase in the risk is especially significant as the forearm shaft fractures are challenging to manage and prone to complications. Paediatric trauma units should prepare themselves for these severe injuries on dry summer days.

[New infectious diseases in Finland--caused by climate change?]. / Uudet infektiotaudit Suomessa--ilmastonmuutosko syynä?

Although the appearance and spreading of most new infectious diseases are likely to be due to globalization or socio-economic changes, the occurrence of tick-, insect- and rodent-borne infections is at least partially dependent on climate variability and change. Climate influences the distribution and life cycle of vectors of arthropod-borne viruses as well as viral evolution and efficacy of transmission. The natural circulation of many pathogens and the development of epidemics are dependent on complex ecological factors, such as biodiversity and predator-prey cycles that in turn are indirectly linked to climate.

Atmospheric pressure and suicide attempts in Helsinki, Finland.

The influence of weather on mood and mental health is commonly debated. Furthermore, studies concerning weather and suicidal behavior have given inconsistent results. Our aim was to see if daily weather changes associate with the number of suicide attempts in Finland. All suicide attempts treated in the hospitals in Helsinki, Finland, during two separate periods, 8 years apart, were included. Altogether, 3,945 suicide attempts were compared with daily weather parameters and analyzed with a Poisson regression. We found that daily atmospheric pressure correlated statistically significantly with the number of suicide attempts, and for men the correlation was negative. Taking into account the seasonal normal value during the period 1971-2000, daily temperature, global solar radiation and precipitation did not associate with the number of suicide attempts on a statistically significant level in our study. We concluded that daily atmospheric pressure may have an impact on suicidal behavior, especially on suicide attempts of men by violent methods (P < 0.001), and may explain the clustering of suicide attempts. Men seem to be more vulnerable to attempt suicide under low atmospheric pressure and women under high atmospheric pressure. We show only statistical correlations, which leaves the exact mechanisms of interaction between weather and suicidal behavior open. However, suicidal behavior should be assessed from the point of view of weather in addition to psychiatric and social aspects.

Climate impact on suicide rates in Finland from 1971 to 2003.

Seasonal patterns of death from suicide are well-documented and have been attributed to climatic factors such as solar radiation and ambient temperature. However, studies on the impact of weather and climate on suicide are not consistent, and conflicting data have been reported. In this study, we performed a correlation analysis between nationwide suicide rates and weather variables in Finland during the period 1971-2003. The weather parameters studied were global solar radiation, temperature and precipitation, and a range of time spans from 1 month to 1 year were used in order to elucidate the dose-response relationship, if any, between weather variables and suicide. Single and multiple linear regression models show weak associations using 1-month and 3-month time spans, but robust associations using a 12-month time span. Cumulative global solar radiation had the best explanatory power, while average temperature and cumulative precipitation had only a minor impact on suicide rates. Our results demonstrate that winters with low global radiation may increase the risk of suicide. The best correlation found was for the 5-month period from November to March; the inter-annual variability in the cumulative global radiation for that period explained 40 % of the variation in the male suicide rate and 14 % of the variation in the female suicide rate, both at a statistically significant level. Long-term variations in global radiation may also explain, in part, the observed increasing trend in the suicide rate until 1990 and the decreasing trend since then in Finland.

Factors affecting outdoor exposure in winter: population-based study.

The extent of outdoor exposure during winter and factors affecting it were examined in a cross-sectional population study in Finland. Men and women aged 25-74 years from the National FINRISK 2002 sub-study (n=6,591) were queried about their average weekly occupational, leisure-time and total cold exposure during the past winter. The effects of gender, age, area of residence, occupation, ambient temperature, self-rated health, physical activity and education on cold exposure were analysed. The self-reported median total cold exposure time was 7 h/week (8 h men, 6 h women),<1 h/week (2 h men, 0 h women) at work, 4 h/week (5 h men, 4 h women) during leisure time and 1 h/week (1 h men, 1.5 h women) while commuting to work. Factors associated with increased occupational cold exposure among men were: being employed in agriculture, forestry and industry/mining/construction or related occupations, being less educated and being aged 55-64 years. Factors associated with increased leisure-time cold exposure among men were: employment in industry/mining/construction or related occupations, being a pensioner or unemployed, reporting at least average health, being physically active and having college or vocational education. Among women, being a housewife, pensioner or unemployed and engaged in physical activity increased leisure-time cold exposure, and young women were more exposed than older ones. Self-rated health was positively associated with leisure time cold exposure in men and only to a minor extent in women. In conclusion, the subjects reported spending 4% of their total time under cold exposure, most of it (71%) during leisure time. Both occupational and leisure-time cold exposure is greater among men than women.