By Isabella Hornick; Perspective by Jeffrey G. Demain, MD, FAAAAI, FACAAI, FAAP

Key takeaways:

• Thunderstorms and power outages together negatively impact the risk for respiratory-related ED visits.

• Researchers evaluated this relationship across six respiratory disease subtypes.

The risk for respiratory-related ED visits in New York was greater on days with both thunderstorms and power outages vs. days with only one of these events, according to results published in Environmental Health Perspectives.

“Unlike most prior studies focusing on asthma only, we considered all respiratory diseases and their subtypes, providing a comprehensive picture regarding the respiratory impacts of thunderstorms and [power outages],” Shao Lin, MD, MPH, PhD, professor in the school of public health at University at Albany, and colleagues wrote.

In this study, Lin and colleagues analyzed 10,674,742 ED visits (30.26% aged 18 to 44 years; 54.19% female; 41.97% white) in New York State during 2005 through 2018 for respiratory diseases to determine how thunderstorms, power outages and a combination of both impact the risk for respiratory-related ED visits via distributed lag nonlinear models.

Researchers also assessed which patients faced greater risks based on demographics and how PM2.5 and relative humidity mediated relationships found.

As Healio previously reported, a large-scale study found that ED visits for thunderstorm-related acute respiratory illnesses were increased in older U.S. adults, including those with asthma and COPD.

The most common respiratory disease subtype within the total cohort was respiratory allergy diseases (39%). The remaining five subtypes had a smaller proportion of ED cases: asthma (22%), respiratory infections (11%), bronchitis (10%), COPD (5%) and “other” (13%).

On days with thunderstorms vs. days with no thunderstorms, researchers observed a significant risk for all respiratory-related ED visits on lag 0 (adjusted risk ratio [aRR] = 1.02; 95% CI, 1.01-1.03) in a model controlling for ozone, temperature, day of the week, holidays, time and year.

Similarly, the risk for all respiratory-related ED visits on lag 0 was significant on days with power outages vs. days with no power outages (aRR = 1.02; 95% CI, 1.01-1.02).

Once combined, researchers found a greater risk on lag 0 (aRR = 1.09; 95% CI, 1.04-1.15) and lag 1 (aRR = 1.05; 95% CI, 1.01-1.09) than those observed in the individual analyses of thunderstorms and power outages.

In the model evaluating thunderstorms and power outages together, the risk ratio ranged from 0.97 to 0.99 on lag 2, 6, 7, 8, 9 and 10, whereas on lag 3, 4 and 5, the risk ratio ranged from 0.95 to 0.96.

Looking at multiday lags in the combined cohort, the risk for all respiratory-related ED visits was heightened on lag 0 to 0 (aRR = 1.09; 95% CI, 1.04-1.15) and lag 0 to 1 (aRR = 1.07; 95% CI, 0.97-1.17). Risk ratios below one were observed in the remaining multiday lags.

Compared with the nonpollen season, the risk for all respiratory-related ED visits on days with both thunderstorms and power outages was greater during grass pollen season (highest RR = 1.28; 95% CI, 1.16-1.4), ragweed season (highest RR = 1.2; 95% CI, 1.12-1.29) and tree pollen season (highest RR = 1.12; 95% CI, 1.04-1.21).

Among the six respiratory disease subtypes, researchers noted higher risks for asthma, COPD, respiratory infections and “other” respiratory diseases on days with only thunderstorms vs. days with only power outages.

On days with thunderstorms vs. days with no thunderstorms, the disease subtype linked to the greatest risk was COPD (RR = 1.12; 95% CI, 1.08-1.17). Similarly, the risk for COPD was the highest of all subtypes on days with power outages vs. days with no power outages (RR = 1.11; 95% CI, 1.09-1.13).

In contrast to the risk ratio range of 1.01 to 1.12 for all but one disease subtype in the models considering thunderstorms alone and power outages alone, the risk ratio range for all subtypes was 1.07 to 1.44 on days with both thunderstorms and power outages.

Based on various demographics and seasons, the risk for respiratory-related ED visits on days with both thunderstorms and power outages differed in multiple instances. The cohort(s) with higher risk in each subgroup included:

• nonresidents vs. residents of New York City (RR = 1.1; 95% CI, 1.05-1.16 vs. 0.76; 95% CI, 0.5-1.15);

• individuals aged 6 to 17 years (RR = 1.37; 95% CI, 1.16-1.62) and 65 years or older (RR = 1.36; 95% CI, 1.2-1.53);

• Hispanic vs. non-Hispanic individuals (RR = 1.25; 95% CI, 1.04-1.5);

• individuals with self-paid insurance (RR = 1.59; 95% CI, 1.29-1.97) and Medicare recipients (RR = 1.35; 95% CI, 1.21-1.5);

• noncore/rural area residents (RR = 1.65; 95% CI, 1.32-2.08); and

• spring (RR = 1.17; 95% CI, 1.06-1.3) and summer seasons (RR = 1.2; 95% CI, 1.12-1.29).

Researchers also found a significant difference in the average number of comorbidities for all respiratory ED cases after vs. before a day with both thunderstorms and power outages (2.874 vs. 2.223).

In terms of modification, five factors significantly modified the impact thunderstorms have on respiratory-related ED visits: extreme cold, extreme heat, high relative humidity, PM2.5 and ozone concentrations.

Lastly, PM2.5 mediated the association between thunderstorms and respiratory-related ED visits by 36%. Similarly, relative humidity mediated the association by 38%.

Perspective

Climate change has brought about more severe weather including an increase in thunderstorms. Shao Lin and colleagues provide a very comprehensive look at multiple variables that contribute to exacerbations of a variety of respiratory diseases during thunderstorms and power outages.

All data were collected to include the period from Jan. 1, 2005, to Dec. 13, 2018. Thunderstorm data in New York State were obtained from the National Oceanic and Atmospheric Administration (NOAA). Weather and air pollution variables including temperature, relative humidity, particulate matter (PM2.5 µm) and ozone (O3 ppm) were collected from the NOAA and the U.S. Environmental Protection Agency.

In order to determine those most impacted, patients were identified by gender, age, race, ethnicity, insurance type, residence area and disease subtype. Patient data and ED visits were obtained from the Statewide Planning and Research Cooperative System of the New York State Department of Health.

Respiratory outcomes during three exposure periods (ie, days with both thunderstorms and power outages, days with thunderstorms only, and days with power outages only) were compared with the control days (ie, neither thunderstorm nor power outages) during the same season in the same regional location.

The authors found that both thunderstorms and power outages alone have similarly significant adverse events. The impact of thunderstorms on respiratory disease was stronger when they coincided with power outages. The joint effects on all respiratory disease were most pronounced on the same day of the event and lasted up to 10 days. Subgroups that demonstrated the greatest risk included school aged children, older adults (aged > 65 years), Hispanic individuals, rural residents and those without insurance.

Additional important variables contributed to higher risk during pollen seasons, spring (trees), summer (grasses) and fall (ragweed). Relative humidity, high PM2.5 and ozone also played a role as additive risk variable.

Thunderstorm-related respiratory events, especially in conjunction with grass pollens, have been well reported in previous studies. The authors have taken a very comprehensive approach to identify additional important variables. To my knowledge this is the first study addressing the joint effect of power outages and thunderstorms and significantly contributes to the literature.

Disclosures: Demain reports having consultant and speaker roles with Blueprint Medicines, an advisory role with Thermo Fisher, a contributor role with Up-to-Date, and co-editor and contributor roles with AAAAI Ask the Expert and Immunology and Allergy Clinics of North America. He also serves on the board of directors of the American Board of Allergy & Immunology.

Sources/DisclosuresCollapse

Source: Lin S, et al. Environ Health Perspect. 2024;doi:10.1289/EHP13237.

Disclosures: An NIH grant supported this study. The authors report no relevant financial disclosures.