Annual incidence of mortality related to hypertensive disease in Canada and associations with heliophysical parameters

Abstract

Increasing research into heliobiology and related fields has revealed a myriad of potential relationships between space weather factors and terrestrial biology. Additionally, many studies have indicated cyclicity in incidence of various diseases along with many aspects of cardiovascular function. The current study examined annual mortality associated with hypertensive diseases in Canada from 1979 to 2009 for periodicities and linear relationships with a range of heliophysical parameters. Analyses indicated a number of significant lagged correlations between space weather and hypertensive mortality, with solar wind plasma beta identified as the likely source of these relationships. Similar periodicities were observed for geomagnetic activity and hypertensive mortality. A significant rhythm was revealed for hypertensive mortality centered on a 9.6-year cycle length, while geomagnetic activity was fit with a 10.1-year cycle. Cross-correlograms of mortality with space weather demonstrated a 10.67-year periodicity coinciding with the average 10.6-year solar cycle length for the time period examined. Further quantification and potential implications are discussed.

Interdisciplinary Analysis of Annual Space Weather Activity in Relation to Mortality Associated with Cerebrovascular Disease: A Novel Model of Solar-Terrestrial Interaction

“…Following our previous research in this area [10], we proceeded to assess the CVD timeseries for additional periodicities after further curve-fitting and de-trending procedures common to many forms of signal processing in order to minimize the dominant cycle inherent to the data and examine potential rhythmic features buried within the overall trend. After inspection of confidence intervals (CI) and calculated root mean squared error terms (RMSE), additional curve-fitting procedures applied to CVD values controlling for population suggested a fourth-order polynomial After de-trending, data were normally distributed.…”

“…Procedures for epidemiological data from our previous research [10] were applied including general statistical methodology and annual disease data source. The annual total numbers of deaths associated with cerebrovascular diseases in Canada (CVD) were obtained for 1979 to 2009 for both males and females and all ages combined from the World Health Organization (WHO) online Mortality Database (http://apps.who.int/healthinfo/statistics/mortality/whodpms/) which includes ICD-10 codes I60 to I69 (Table 1).…”

“…Aside from the standard analysis of linear relationships between space weather and epidemiological measures of interest, we also employed signal processing techniques more amenable to smaller samples which included least-squares fitting of trigonometric approximations describing potential cycles in a timeseries. Where necessary, variable distributions were normalized following previous suggestion in similar contexts [10,22] according to Blom's [23] method of transformation:…”

“…Of particular relevance for the current research, Zeng et al [21] recently identified strong coperiodicities in patterns of daily mortality due to both cardio-and cerebrovascular diseases in China with a number of heliogeophysical variables including solar and geomagnetic activity, as well as the interplanetary magnetic field. Additionally, we [10] have previously described significant linear phase shifted correlations between space weather parameters, particularly related to dynamic pressure changes of solar wind, and annual hypertensive disease mortality in Canada, along with the identification of relevant overlapping cycles between measures.…”

“…This approach has proven particularly effective for the integration of biology with the lowest orders of discourse within physics through the highest orders of astronomy and also for exploring especially novel theoretical perspectives, many of which contribute to a greater overall understanding of potential mechanisms of action for various phenomena of interest [1][2][3][4][5][6][7][8][9]. We previously applied a similar interdisciplinary perspective within the area of chronoepidemiology [10] which revealed a number of interesting post-hoc theoretical approaches to heliogeophysical influence on terrestrial systems. The current study was undertaken in order to help describe a novel model of solar-terrestrial interaction involving dynamic pressure systems and magnetic energies derived from empirical data and the analysis of heliogeophysical and epidemiological time-series.…”