Temporal patterns of suicide and circulatory system disease-related mortality are inversely correlated in several countries

Background Nearly 800,000 suicides occur worldwide annually and suicide rates are increasing faster than population growth. Unfortunately, the pathophysiology of suicide remains poorly understood, which has hindered suicide prevention efforts. However, mechanistic clues may be found by studying effects of seasonality on suicide and other mortality causes. Suicides tend to peak in spring-summer periods and nadir in fall-winter periods while circulatory system disease-related mortality tends to exhibit the opposite temporal trends. This study aimed to determine for the first time whether monthly temporal cross-correlations exist between suicide and circulatory system disease-related mortality at the population level. If so and if common biological factors moderate risks for both mortality types, such factors may be discoverable and utilized to improve suicide prevention. Methods We conducted time series analyses of monthly mortality data from northern (England and Wales, South Korea, United States) and southern (Australia, Brazil) hemisphere countries during the period 2009–2018 (N = 41.8 million all-cause mortality cases). We used a Poisson regression variant of the standard cosinor model to determine peak months of mortality. We also estimated cross-correlations between monthly mortality counts from suicide and from circulatory system diseases. Results Suicide and circulatory disease-related mortality temporal patterns were negatively correlated in Australia (− 0.32), Brazil (− 0.57), South Korea (− 0.32), and in the United States (− 0.66), but no temporal correlation was discernable in England and Wales. Conclusions The negative temporal cross-correlations between these mortality types we found in 4 of 5 countries studied suggest that seasonal factors broadly and inversely moderate risks for circulatory disease-related mortality and suicide, but not in all regions, indicating that the effect is not uniform. Since the seasonal factors of temperature and light exert opposite effects on suicide and circulatory disease-related mortality in several countries, we propose that physiologically-adaptive circulatory system responses to heat and light may increase risk for suicide and should be studied to determine whether they affect suicide risk. For example, heat and light increase production and release of the bioactive gas nitric oxide and reduce circulatory system disease by relaxing blood vessel tone, while elevated nitric oxide levels are associated with suicidal behavior, inverse effects that parallel the inverse temporal mortality patterns we detected.

Temporal patterns of suicide and circulatory system disease-related mortality are inversely correlated in several countries

Background Nearly 800,000 suicides occur worldwide annually and suicide rates are increasing faster than population growth. Unfortunately, the pathophysiology of suicide remains poorly understood, which has hindered suicide prevention efforts. However, mechanistic clues may be found by studying effects of seasonality on suicide and other mortality causes. Suicides tend to peak in spring-summer periods and nadir in fall-winter periods while circulatory system disease-related mortality tends to exhibit the opposite temporal trends. This study aimed to determine for the first time whether monthly temporal cross-correlations exist between suicide and circulatory system disease-related mortality at the population level. If so and if common biological factors moderate risks for both mortality types, such factors may be discoverable and utilized to improve suicide prevention.Methods We conducted time series analyses of monthly mortality data from northern (England and Wales, South Korea, United States) and southern (Australia, Brazil) hemisphere countries during the period 2009-2018 (N=41.8 million all-cause mortality cases). We used a Poisson regression variant of the standard cosinor model to determine cross-correlations between monthly mortality rates from suicide and from circulatory system diseases.Results Suicide and circulatory disease-related mortality temporal patterns were negatively correlated in Australia (-0.32), Brazil (-0.57), South Korea (-0.32), and in the United States (-0.66), but no temporal correlation was discernable in England and Wales.Conclusions The negative temporal cross-correlations between these mortality types we found in 4 of 5 countries studied suggest that seasonal factors broadly and inversely moderate risks for circulatory disease-related mortality and suicide. Since the seasonal factors of temperature and light exert opposite effects on suicide and circulatory disease-related mortality in several countries, we propose that physiologically-adaptive circulatory system responses to heat and light may increase risk for suicide and should be studied to determine whether they affect suicide risk. For example, heat and light increase production and release of the bioactive gas nitric oxide and reduce circulatory system disease by relaxing blood vessel tone, while elevated nitric oxide levels are associated with suicidal behavior, inverse effects that parallel the inverse temporal mortality patterns we detected.

Regional Variability in the Access to Cardiac Rehabilitation in Poland

Equitable access to cardiological rehabilitation services is one of the important elements in the effectiveness of the treatment of cardiovascular diseases as cardiological rehabilitation is an important part of circulatory system disease prevention and treatment. However, in many countries among others, Poland suffers from the underutilization of cardiac rehabilitation services. Cardiovascular diseases are the worldwide number one cause of mortality, morbidity, and disability and are responsible for the substantial increase in health care costs. Thus, the aim of the research was the analysis of geographical accessibility to cardiac rehabilitation services in Poland. Perkal’s method was employed in this research. The conducted research allowed to recognize the regional variation, but also made it possible to classify Polish voivodeships in terms of the level of availability achieved. This enables the identification of voivodeships that provide a good, or even very good, access to cardiology rehabilitation services and those characterized by low, or very low access. It was found that there was a slight regional variability in the access to cardiological rehabilitation services. However, the sufficient development of a rehabilitation infrastructure has been also recognized.

Difference in the characteristics of mortality reports during a heatwave period: retrospective analysis comparing deaths during a heatwave in January 2014 with the same period a year earlier

ObjectivesTo describe the characteristics of deaths reported to the Coroners Court of Victoria (CCOV) during Victoria’s last heatwave (14–17 January 2014) and subsequent 4 days (18–21 January) using medicolegal data obtained from both the police investigation report and the pathologist’s report.Design, setting and participantsA single-jurisdiction population-based retrospective analysis of consecutive heat-related deaths (HRDs) reported to the CCOV between 14 and 21 January 2014 with a historical comparison group.Main outcome measuresDescriptive statistics were used to summarise case demographics, causes of death and the types of investigations performed. The cases from 2014 were subgrouped into HRD and non-HRD.ResultsOf the 222 cases during the study period in 2014, 94 (42.3%) were HRDs and 128 (57.7%) were non-HRDs. HRDs were significantly older than non-HRDs (70.5 years: SD=13.8 vs 61.0 years: SD=22.4, t(220)=3.60, p<0.001, 95% CI 4.3 to 14.6). The most common primary cause of death in HRDs was circulatory system disease (n=57, 60.6%), which was significantly higher when compared with non-HRDs (n=39, 30.5%; χ2=20.1, p<0.001, OR 3.5, 95% CI 2.0 to 6.2). HRDs required significantly greater toxicology investigation (89.4% (n=84) vs 71.9% (n=92); χ2=10.9, p<0.001, OR 3.3, 95% CI 1.54 to 7.03) and greater vitreous biochemistry testing (40.4% (n=38) vs 16.4% (n=21); χ2=16.0, p<0.001, OR 3.5, 95% CI 1.9 to 6.5).ConclusionsA heatwave places a significant burden on death investigation services. The inclusion of additional laboratory tests and more detailed circumstantial information are essential if the factors that contribute to HRDs are to be identified.