The influence of seasonal climate variability on mortality in pre-industrial Sweden

Figures & data

Fig. 1 Trends in annual numbers of deaths (bars) and population size (lines), Uppsala Domkyrka parish, 1749–1859.

Fig. 2 Annual precipitation (cm) in Uppsala, 1749–1859 (smooth spline).

Table 1 Association of annual and seasonal temperature (°C) and precipitation (cm) with annual mortality, Uppsala Domkyrka parish 1749–1859, both sexes

	Model 1	Model 2
	RR (95% CI)	RR (95% CI)
Annual climate
Annual temperature	1.036 (0.965–1.113)	–
Annual precipitation	1.004 (0.997–1.010)	–
Seasonal climate
Winter temperature	1.007 (0.984–1.030)	1.013 (0.988–1.038)
Winter precipitation	0.992 (0.965–1.020)	0.990 (0.961–1.020)
Spring temperature	0.970 (0.935–1.007)	0.962 (0.923–1.003)
Spring precipitation	0.986 (0.969–1.002)	0.982 (0.965–1.000)
Summer temperature	1.025 (0.976–1.077)	1.048 (0.997–1.102)
Summer precipitation	1.009 (0.996–1.021)	1.007 (0.994–1.020)
Autumn temperature	1.037 (0.984–1.094)	1.031 (0.976–1.090)
Autumn precipitation	1.013 (1.002–1.025)	1.018 (1.004–1.032)

Borderline significant results (p=0.05–0.1) in italics. Significant results (p<0.05) in bold.

Model 1: Temperature and precipitation per year, respectively, per season, simultaneously included in the model.

Model 2: Full seasonal model with all seasonal climate variables simultaneously included.

RR, relative risk; CI, confidence interval.

RR values below 1.0 indicate higher temperature resp. precipitation leading to decreasing mortality, while values above 1.0 indicate increases in mortality.

Table 2 Association of annual and seasonal temperature (°C) and precipitation (cm) with annual mortality, Uppsala Domkyrka parish 1749–1859, sex-stratified results

	Men	Women
	RR (95% CI)	RR (95% CI)
Annual climate*
Annual temperature	1.030 (0.960–1.104)	1.042 (0.961–1.130)
Annual precipitation	1.003 (0.997–1.010)	1.004 (0.997–1.011)
Seasonal climate**
Winter temperature	1.011 (0.987–1.036)	1.015 (0.986–1.045)
Winter precipitation	0.987 (0.959–1.017)	0.993 (0.959–1.027)
Spring temperature	0.959 (0.921–1.000)	0.965 (0.919–1.013)
Spring precipitation	0.985 (0.968–1.002)	0.980 (0.960–1.000)
Summer temperature	1.039 (0.989–1.091)	1.058 (0.997–1.122)
Summer precipitation	1.007 (0.994–1.019)	1.007 (0.992–1.023)
Autumn temperature	1.042 (0.986–1.100)	1.021 (0.958–1.088)
Autumn precipitation	1.017 (1.003–1.031)	1.020 (1.004–1.036)

Borderline significant results (p=0.05–0.1) in italics. Significant results (p<0.05) in bold.

* Annual temperature and precipitation simultaneously included in the model; **Seasonal climate: All seasonal climate variables simultaneously included in the model.

RR, relative risk; CI, confidence interval.

RR values below 1.0 indicate higher temperature resp. precipitation leading to decreasing mortality, while values above 1.0 indicate increases in mortality.

Table 3 Association of seasonal temperature and precipitation with annual mortality, Uppsala Domkyrka parish in three periods between 1749 and 1859, both sexes

	1749–1785	1786–1824	1825–1859
	RR (95% CI)	RR (95% CI)	RR (95% CI)
Winter temperature	1.049 (1.003–1.098)	0.990 (0.965–1.015)	1.004 (0.942–1.071)
Winter precipitation	1.030 (0.978–1.085)	1.045 (0.997–1.096)	0.941 (0.894–0.991)
Spring temperature	0.956 (0.887–1.031)	0.978 (0.936–1.022)	0.980 (0.899–1.069)
Spring precipitation	0.972 (0.947–0.999)	0.965 (0.935–0.995)	0.999 (0.967–1.031)
Summer temperature	1.027 (0.946–1.114)	1.017 (0.960–1.078)	1.107 (0.993–1.235)
Summer precipitation	0.995 (0.977–1.014)	0.996 (0.976–1.016)	0.994 (0.967–1.021)
Autumn temperature	0.970 (0.886–1.062)	1.019 (0.948–1.094)	1.044 (0.934–1.166)
Autumn precipitation	0.997 (0.962–1.034)	1.000 (0.980–1.021)	1.024 (0.997–1.052)

Borderline significant results (p=0.05–0.1) in italics. Significant results (p<0.05) in bold.

All seasonal climate variables simultaneously included in the model.

RR, relative risk; CI, confidence interval.

RR values below 1.0 indicate higher temperature resp. precipitation leading to decreasing mortality, while values above 1.0 indicate increases in mortality.