COPD patients experience worse breathing symptoms and equally worse bronchitis symptoms in high and low outside temperatures respectively, finds a recent study. The latest study by researchers from the Harvard Medical School in Boston and published in ERJ Open Research, observed that COPD patients experienced exacerbations in breathing symptoms including cough and phlegm with increasing temperatures and low temperatures were associated with symptoms of bronchitis. The research, which included about 30 COPD patients with a former smoking history, calculated their daily exposure to temperature and relative humidity to find that lower outdoor temperature was associated with worsening bronchitis symptoms. It also observed a non-linear, U-shaped relationship in which the highest quantities of both warmer and colder outdoor temperature exposure were associated with higher odds of breathing symptoms.