Occupational cold exposure is associated with increased reporting of airway symptoms

Abstract

Objective To determine if exposure to cold environments, during work or leisure time, was associated with increased reporting of airway symptoms in the general population of northern Sweden. Methods Through a population-based postal survey responded to by 12627 subjects, ages 18–70, living in northern Sweden, the occurrence of airway symptoms was investigated. Cold exposure during work or leisure time was self-reported on numerical rating scales. Binary logistic regression was used to determine the statistical association between cold exposure and airway symptoms. Results For currently working subjects (N = 8740), reporting any occupational cold exposure was associated to wheeze (OR 1.3; 95% CI 1.1–1.4); chronic cough (OR 1.2; 95% CI 1.1–1.4); and productive cough (OR 1.3; 95% CI 1.1–1.4), after adjusting for gender, age, body mass index, daily smoking, asthma, and chronic obstructive pulmonary disease. Leisure-time cold exposure was not significantly associated to reporting airway symptoms. Conclusions Occupational cold exposure was an independent predictor of airway symptoms in northern Sweden. Therefore, a structured risk assessment regarding cold exposure could be considered for inclusion in the Swedish workplace legislation.

Occupational cold exposure in relation to incident airway symptoms in northern Sweden: a prospective population-based study

“…More likely, the exposure measure in the present study was simply not detailed enough to capture such effects. There were no clear effects of leisure-time cold exposure on incident airway symptoms, well in line with the previous study (Stjernbrandt et al 2021 ). It has not been fully understood why occupational cold exposure appears to be more strongly associated with airway symptoms than leisure-time exposure, even though the latter can constitute a larger contribution to the total exposure on a population level (Mäkinen et al 2006 ).…”

“…In the first cross-sectional study on this cohort, both wheeze, long-standing cough and productive cough were associated with occupational cold exposure (Stjernbrandt et al 2021 ). However, in this longitudinal continuation, associations were found only for incident wheeze and productive cough, but not incident long-standing cough.…”

“…Apart from manifest diagnoses of asthma and COPD, several large epidemiological studies in Finland have indicated that airway symptoms, such as wheeze, cough, and increased sputum production are more prevalent in subjects living in cold climate (Kotaniemi et al 2003 ; Näyhä et al 2011 ; Raatikka et al 2007 ), with an especially high occurrence among smoking outdoor workers (Kotaniemi et al 2002 ). There are several indications that individuals occupationally exposed to cold climate are at higher risk for airway symptoms than other workers, which might be due to longer and more intense exposure to low temperatures, but also because of increased ventilation during strenuous manual work, inducing respiratory tract cooling and subsequent airway dysfunction (Mäkinen 2007 ; Stjernbrandt et al 2021 ). Moreover, while some previous studies have reported that cold air is merely a trigger for airway symptoms (Koskela 2007 ), others have suggested that it might actually be a causal factor for the emergence of airway disease (Giesbrecht 1995 ; Kotaniemi et al 2003 ).…”

“…Moreover, while some previous studies have reported that cold air is merely a trigger for airway symptoms (Koskela 2007 ), others have suggested that it might actually be a causal factor for the emergence of airway disease (Giesbrecht 1995 ; Kotaniemi et al 2003 ). In 2015, we conducted a cross-sectional population-based study in northern Sweden, revealing associations between occupational cold exposure and reporting of airway symptoms (Stjernbrandt et al 2021 ). However, there have been no previous longitudinal studies on the topic, and this paper represents a continuation of the previous project.…”

A prospective study on local cold injuries in northern Sweden

“…There were surprisingly weak associations between cold exposure and incident local cold injuries, and this raises concern about the validity of these exposure variables. The reason for occupational cold exposure tending towards a higher probability for incident local cold injuries in comparison to that of leisure-time cold exposure, could be that during working-time outdoor exposure is more mandatory and there is usually a lower ability to adjust the ambient circumstances to the individuals’ needs and comfort [ 36 ]. Finally, there were many statistical tests performed, which increases the risk of type 1-error.…”