Air Temperature and Inflammatory and Coagulation Responses in Patients with Coronary or Pulmonary Diseases

Abstract

ISEE-0195 Background and Objective: Air temperature changes have been associated with increased cardiovascular and respiratory risk, but the role of inflammation and coagulation markers in these relationships is not well understood. We investigated the associations between temperature and several blood markers in individuals with coronary heart disease (CHD) and pulmonary disease (PD). Methods: Two panel studies were conducted in Erfurt, Germany, in two subsequent winters. In total, 578 and 381 repeated blood measurements from 57 CHD and 38 PD patients were collected, respectively. Data on patient characteristics and disease history were gathered at the baseline visit. Meteorological data were collected from existing networks. Associations were analyzed using additive mixed models with random patient effects. Effect modification by diabetes status was investigated only in CHD patients, as only two diabetic individuals were part of the PD panel. Results: Mean daily air temperature varied between −13°C and 16°C in both study periods. A 10° decrease in the 5-day-average of temperature before the blood withdrawal led to an increase in fibrinogen (%-change from the mean: 5.5%; 95%-confidence interval (CI): [1.3%; 9.7%]) and platelet counts (3.0%; 95%-CI: [0.6%; 5.5%]), and to no change in C-reactive protein in PD patients, whereas for CHD patients a decrease was observed. A two day delayed increase in factor VII in association with a temperature decrease was seen in CHD patients (4.9%; 95%-CI: [0.7%; 9.2%]), while PD patients showed no effect. The effects in CHD patients without diabetes were similar to those of the PD patients, whereas diabetic CHD patients showed a strong effect (12.1%; 95%-CI: [5.8%; 18.9%]). Conclusions: The present study suggests that a temperature decrease is associated with a change in several blood parameters. It can only be speculated that the partly opposite findings in CHD and PD patients might be influenced by their differing diabetic status.