3 DECEMBER 2021 ausdoc . com . au
Table 2 . Individual interventions to reduce risk of air pollution Activity Wearing face masks
Installing air purifiers
Lifestyle and preventive measures
Reducing in-traffic exposures
Staying indoors
Reducing the amount of outdoor air pollution that penetrates the home
Following air quality information
Source : Brook RD et al 207
Considerations
Figure 3 . Australia ’ s carbon emissions .
35 % 30 % 25 % 20 % 15 % 10 % 5 % 0 % -5 % -10 %
Energy ( electrical )
Energy ( direct combustion )
Source : Australian Government 293
High-efficiency face masks reduce acute CV effects of air pollution in patients with CAD living in areas of high pollution 285 N95 masks are protective , and reduce BP and HR variability 286 Mask effectiveness depends on filtration capacity Masks may be uncomfortable in hot weather and are not well tolerated by children and older individuals
Air purifiers with HEPA filters reduce indoor PM 2 . 5 by more than 50 % and lead to improvements in
287 , 288
BP , insulin sensitivity , inflammatory markers , stress hormones and metabolic profiles
Statins and a healthy diet may help mitigate the cardiopulmonary effects of air pollution 289 Exercise may attenuate the adverse effects of air pollution , but excessive inhalation of pollutants
290 , 291
during exercise may negate any protective effect Avoid exercise outdoors when air quality is poor / during peak exposure times , avoid roadways / traffic Be aware of health risks of travel to heavily polluted regions
Avoid commutes during rush hour , install in-cabin HEPA filters , close car windows , recirculate in-cabin air
Provides some protection , dependant on ventilation and building quality Outdoor pollutants may penetrate houses in very bad conditions , if air-conditioning systems lack high-efficiency air filters or houses lack air purifiers
Close windows , use door and window seals , indoor air purifiers and air-conditioning filters
Local air quality can vary rapidly ; real-time hourly PM 2 . 5 data and smoke forecasts can help plan daily activities and reduce exposure to air pollution . Use smartphone apps , eg , AirRater 292
Transport
% of total emissions
Agriculture
Fugitive emissions
Industrial processes
Waste
Land use , land use change and forestry
Box 1 . Cardiac benefits from GHG reductions
• Dietary changes :
— Choosing a plant-based diet , reducing consumption of ruminant meat , and dairy ( particularly cheese ) contributes to the mitigation of climate change and has cardiac health benefits . 294-296 Farming is a significant source of GHG emissions , and contributes to water pollution as well as deforestation . 297-299
— Reduce processed / extensively packaged foods . These are often high in fat and sugar , require large amounts of petroleum-based fuels in their production and generate large amounts of plastic waste ( see figures 4 and 5 ). Consume locally produced , seasonal fresh fruits and vegetables to reduce carbon emissions from transport and packaging . 300
— Buy organic foods if possible . These have lower pesticide residues ,
301 , 302 providing greater levels of certain nutrients .
• Increase active transport :
— Incorporate physical activity into the daily commute . Increasing active transport reduces obesity , CAD , diabetes and cancer , and also reduces air pollution , traffic and GHG emissions . 303 , 304 Walking reduces obesity compared with time spent in a car , which increases obesity risk . 304 Those walking or cycling to work have reduced CVD and all-cause
305 , 306 mortality . — Postmenopausal women who walk have reduced CVE and women
307 , 308 who cycle have reduced all-cause mortality . — Commuting by car is associated with an increased risk of MI compared with commuting by bus , cycling or walking . 309
• Change to renewable energy source :
— Renewable energy sources ( solar / wind ) instead of fossil fuel combustion ( especially coal ) for heat and electricity improves air quality and lowers CVD risk . 310 Reductions in air pollution reduce CVE
303 , 310 , 311 and improve life expectancy .
• Increase green spaces :
— These may be public or private and include green infrastructure , natural open spaces , community gardens , school grounds , shorelines or similar .
— Health benefits including lower rates of mortality , obesity , CVD , mental illness and stress . 312-314
— Green spaces mitigate climate change and improve resilience and recovery from the impacts of climate change . Providing shade and reducing the urban heat island effect reduces heat illness and premature death from extreme heat ; improved air quality lowers
315 , 316 rates of CVD from air pollution .
• Stop smoking :
— Smoking is a known risk factor for CVD . Fine PM from active cigarette smoking and second-hand smoke increases CVD mortality . 317 The significant environmental impact of smoking includes tobacco growing , manufacturing and distribution , consumption , and postconsumption waste . 318
• Architectural solutions : — Improved housing insulation , which reduces excessive heating of indoor spaces , can provide cardiac health benefits while reducing
55 , 319 , 320 energy use .
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and haemostatic / prothrombotic responses to this strain lead to ischaemia and arrhythmias , or plaque rupture and thrombus formation causing a CVE . 268 , 270 The ultimate cause of death is a terminal arrhythmia ; this may result from an MI in those with CHD , or may be associated with cardiomegaly
271 , 272 or left ventricular hypertrophy .
Firefighters have higher burdens of classic CVD risk factors ( smoking , hypertension , obesity ). 273 On-duty CVEs occur almost exclusively in firefighters with previously diagnosed CVD , underlying structural heart disease , CVD factors and subclinical
271 , 273 , 274
CHD , or a combination of these . Age over 60 increases risk of SCD . 263
Strategies to reduce CVE in this
group includes annual medical evaluations for all firefighters ; banning smoking / tobacco use in fire services ; wellness programs promoting exercise and healthy diets ; aggressive treatment of CVD risk factors ; education ; screening ; and investigations to detect subclinical disease . 275
Increased thrombogenicity and impaired vascular function have been observed secondary to an increase in core body temperature and dehydration . 276 Thus , limiting the duration of extreme exposures , active cooling , and rehydration following heat exposure and physical exertion may help mitigate the CVD risk . Aspirin may have a role after a bout of firefighting . 277
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Figure 4 . Plastic waste .
MANAGEMENT
Acute management
TO help patients cope with intense heat exposure , encourage them to increase ( non-alcoholic ) fluid intake , avoid the hottest environments , wear loose-fitting clothes , take frequent cool showers or baths , and reduce physical activity . 278 Reduce working hours if working in hot environments and where possible use air conditioning or seek a public space with air conditioning . This reduces heat-related health risk and risk of death during heatwaves . 279 However , extensive use of air conditioning may increase energy demands and contribute to the urban heat island effect ; power
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outages also limit the protective effect
280 , 281 of air-conditioning .
Patients on CV drugs ( particularly diuretics , beta blockers , renin-angiotensin system inhibitors and anticholinergic drugs ) require increased monitoring / dose adjustment and may need temporary suspension .
Increase patient awareness regarding symptoms of heat exhaustion and heat stroke . 282 Inpatient education regarding preventive behavioural change could help reduce temperature-related readmission of CHD / stroke . 283 Individual interventions to reduce risk of air pollution are in table 2 .
The greatest mortality PAGE 36
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Figure 5 . Plastic waste . |