Mortality effects of temperature changes in the United Kingdom

Abstract

Temperature changes are known to affect the social and environmental determinants of health in various ways. Consequently, excess deaths as a result of extreme weather conditions may increase over the coming decades because of climate change. In this paper, the relationship between trends in mortality and trends in temperature change (as a proxy) is investigated using annual data and for specified (warm and cold) periods during the year in the UK. A thoughtful statistical analysis is implemented and a new stochastic, central mortality rate model is proposed. The new model encompasses the good features of the Lee and Carter (Journal of the American Statistical Association, 1992, 87: 659–671) model and its recent extensions, and for the very first time includes an exogenous factor which is a temperature‐related factor. The new model is shown to provide a significantly better‐fitting performance and more interpretable forecasts. An illustrative example of pricing a life insurance product is provided and discussed.

The impact of parameter uncertainty in insurance pricing and reserve with the temperature‐related mortality model

“…x,t is the error term at age x and time t. Additionally, it should be clarified that the temperature effect, ct x , focuses on population groups above the age a, which for the UK is calculated to be a = 50 (Christidis et al, 2010;Seklecka et al, 2017).…”

“…The goodness of fit is tested by using three standard measures: mean absolute percentage error (MAPE), 7 mean absolute deviation (MAD), 8 and Bayesian information criterion (BIC). 9 Table 1 displays the fitting performance of the Lee and Carter (1992), Renshaw and Haberman (2006), Plat (2009), O'Hare andLi (2012), and Seklecka et al (2017) models for UK males, aged 20-85. As we can observe, the TRM model gives the best-fitting results, based on all the criteria applied.…”

“…13 The Met Office provides detailed climatic data for the UK; available at www.metoffice.gov.uk/datapoint. Although Seklecka et al (2017) considered mortality rates separately for cold and warm months and annual data, this paper is aimed at examining the model's risk and parameter uncertainty, insurance pricing, and reserving. The calculations are based on annual HMD data.…”

“…Previous studies were focused on the age range 20-85+ (Seklecka et al, 2017). In this subsection, the impact of age range is measured for particular age ranges, such as 0-89, 20-85+, 20-89, and 50-89, using the three standard measures as described in Section 2: MAPE, BIC, and MAD.…”

“…Recently, Seklecka, Pantelous, and O'Hare (2017) introduced a new temperature-related mortality (TRM) model in which an additional factor related to climate change was included. The main structure of the TRM model is based on the celebrated Lee and Carter (1992) model and its numerous extensions.…”