Table 2.

Association between indoor temperature and COPD symptoms, rescue medication use, and lung function

Outcome	Coefficient*	95% Confidence Interval	P Value
Breathlessness, Cough, and Sputum Scale
Daily temperature (limited model)†	0.30	0.00–0.59	0.048
Daily temperature (with humidity, NO2, PM2.5)	0.38	0.01–0.67	0.013
Lag 0	0.30	0.00–0.59	0.048
Lag 1	0.36	0.01–0.70	0.042
Lag 2	0.48	0.12–0.85	0.010
Lag 3	0.10	−0.27–0.47	0.602
Rescue inhaler use
Daily temperature (limited model)†	0.26	0.09–0.42	0.002
Daily temperature (with humidity, NO2, PM2.5)	0.23	0.06–0.41	0.008
Lag 0	0.26	0.09–0.42	0.002
Lag 1	0.17	-0.02–0.36	0.077
Lag 2	0.21	-0.01–0.42	0.058
Lag 3	−0.02	−0.24–0.20	0.845
Lung function (evening FEV1)
Daily temperature (limited model)†	−0.02	−0.05–0.02	0.419
Daily temperature (with humidity, NO2, PM2.5)	−0.01	−0.05–0.02	0.439
Lag 0	−0.02	−0.05–0.02	0.419
Lag 1	−0.01	−0.04–0.03	0.610
Lag 2	−0.01	−0.05–0.02	0.418
Lag 3	−0.02	−0.06–0.02	0.262

Definition of abbreviations: COPD = chronic obstructive pulmonary disease; PM = particulate matter.

^*Models include visit, age, sex, education, baseline FEV₁. (Number of pack-years was used instead of baseline FEV₁ in the lung function models).

^†Changes are expressed per 10°F increase in indoor temperature.