Table 2. Poisson regression models depicting the effect of climatic variables on admission rates for ST-elevation myocardial infarction (STEMI) in women and men ≤55 years of age.

Univariate Poisson Regression	Women≤55 years			Men≤55 years			All
Climate variable	RR	95% CI	p-value	RR	95% CI	p-value	RR	95% CI	p-value
Spring/Summer-Season(April-Sept)	1.66	1.12–2.46	0.012	0.86	0.72–1.02	0.09	0.96	0.88–1.04	0.32
Maximal daily temperature >15°C	1.70	1.15–2.51	0.007	0.80	0.67–0.95	0.011	0.95	0.87–1.03	0.21
Daylight >12 hrs	1.67	1.12–2.47	0.011	0.88	0.74–1.05	0.16	0.95	0.87–1.03	0.23
Maximal daily temperature (per single degree [C°] increase)	1.02	1.00–1.04	0.02	0.99	0.99–0.99	0.02	0.99	0.99–1.00	0.29
Multivariate Poisson Regression
Climate variable	RR	95% CI	p-value	RR	95% CI	p-value		95% CI	p-value
Spring/Summer-Season (April-Sept)	2.40	1.06–5.43	0.036	0.85	0.59–1.24	0.403	1.03	0.86–1.23	0.77
Maximal daily temperature >15°C	2.00	1.1–3.7	0.029	0.75	0.57–0.98	0.034	0.97	0.85–1.10	0.62
Daylight >12 hrs	1.78	1.18–2.67	0.06	0.85	0.71–1.02	0.082	0.94	0.87–1.03	0.18
Maximal daily temperature (per single degree [C°] increase)	1.00	1.00–1.04	0.01	0.99	0.98–1.00	0.007	1.00	0.99–1.00	0.24

Upper panel. Univariate Poisson regression analysis testing the effect of season, temperature>15°C (categorical variable), daylight>12hrs (categorical variable) and maximal daily temperature (risk per single °C increase) on admission rates for STEMI. Lower panel. Multivariate Poisson regression analysis testing the effect of season, temperature>15°C (categorical variable), daylight>12hrs (categorical variable) and maximal daily temperature (risk per single °C increase) on admission rates for STEMI. Each variable was adjusted for total rain, total snow fall, relative humidity and wind speed. Due to collinearity daylight and temperature were not tested in the same model. RR, relative risk; CI, confidence interval.