Smoking habits trump asthma, obesity in risk factors for otherwise healthy population
EDITOR'S NOTE: On April 4, coronavirus cases in Rhode Island reached a peak average age of 55 years. Since then, the average age of people with new infections has dropped steadily and is now at 38 years old. The largest bloc of cases (32%) are between 20 and 39 years old. -Will Collette
As the number of young adults infected with the coronavirus surges throughout the nation, a new study by researchers at UC San Francisco Benioff Children’s Hospitals indicates that youth may not shield people from serious disease.
As the number of young adults infected with the coronavirus surges throughout the nation, a new study by researchers at UC San Francisco Benioff Children’s Hospitals indicates that youth may not shield people from serious disease.
The study
looked at data drawn from a nationally representative sample of approximately
8,400 men and women ages 18 to 25 and concluded that overall “medical
vulnerability” was 33 percent for males and 30 percent for females.
The impact of smoking surpassed other less common risks, the UCSF researchers reported in their study, which publishes in the Journal of Adolescent Health on July 13, 2020.
The impact of smoking surpassed other less common risks, the UCSF researchers reported in their study, which publishes in the Journal of Adolescent Health on July 13, 2020.
Data from the
U.S. Centers for Disease Control and Prevention (CDC), not included in the UCSF
study, indicates that while patients over 65 are significantly more likely to
be hospitalized than younger people, the gap is narrowing.
For the week ending April 18, there were 8.7 hospitalizations per 100,000 of the population for the 18-to-29 age bracket, compared with 128.3 per 100,000 of the population for patients over 65. By the week ending June 27, the figures were 34.7 and 306.7 respectively, representing a 299 percent increase in hospitalizations for young adults, versus a 139 percent increase in hospitalizations for older adults.
For the week ending April 18, there were 8.7 hospitalizations per 100,000 of the population for the 18-to-29 age bracket, compared with 128.3 per 100,000 of the population for patients over 65. By the week ending June 27, the figures were 34.7 and 306.7 respectively, representing a 299 percent increase in hospitalizations for young adults, versus a 139 percent increase in hospitalizations for older adults.
The
researchers, led by first author Sally Adams, PhD, of the UCSF Division of Adolescent and
Young Adult Medicine, determined vulnerability by referencing
indicators identified by the CDC.
These included heart conditions, diabetes, current asthma, immune conditions (such as lupus, gout, rheumatoid arthritis), liver conditions, obesity and smoking within the previous 30 days.
Additionally, the researchers added e-cigarettes to tobacco and cigar use, which the CDC had included, stating that all three were associated with adverse effects on respiratory and immune function.
These included heart conditions, diabetes, current asthma, immune conditions (such as lupus, gout, rheumatoid arthritis), liver conditions, obesity and smoking within the previous 30 days.
Additionally, the researchers added e-cigarettes to tobacco and cigar use, which the CDC had included, stating that all three were associated with adverse effects on respiratory and immune function.
Since there was
no data on the relative impact of each of the CDC risk factors, the researchers
used an overall medical vulnerability estimate of having at least one of the
indicators as the outcome variable, rather than a cumulative score of
indicators. Thus, medical vulnerability was assessed according to each
indicator, so that among smokers for example, 100 percent were vulnerable for
severe COVID-19.
Most notable
among their results was that medical vulnerability stood at 16.1 percent for
the 6,741 non-smokers, versus 31.5 percent for the full sample of 8,405 young
adults, which included smokers.
Smoking Linked
to Progression of COVID-19
“Recent
evidence indicates that smoking is associated with a higher likelihood of
COVID-19 progression, including increased illness severity, ICU admission or
death,” said Adams. “Smoking may have significant effects in young adults, who
typically have low rates for most chronic diseases.”
Recent research
also shows that young adults are starting to smoke at higher rates than
adolescents, a reversal of previous trends, she noted.
The study,
which used data from the National Health Interview Survey, found that over the
previous 30 days, 10.9 percent had smoked a cigarette, 4.5 percent had smoked a
cigar product and 7.2 percent had smoked an e-cigarette. The number of smokers
– 1,664 or 19.8 percent – was higher than the number of people with asthma (8.6
percent), obesity (3 percent) and immune disorders (2.4 percent).
Additionally, 1.2 percent had diabetes, 0.6 percent had a liver condition and 0.5 percent had a heart condition.
Additionally, 1.2 percent had diabetes, 0.6 percent had a liver condition and 0.5 percent had a heart condition.
“The risk of
being medically vulnerable to severe disease is halved when smokers are removed
from the sample,” said senior author Charles Irwin Jr., MD, of the UCSF Division of
Adolescent and Young Adult Medicine. “Efforts to reduce smoking and e-cigarette
use among young adults would likely lower their vulnerability to severe
disease.”
Gender
differences were noted in five vulnerability indicators. Women were more likely
to have asthma, (10 percent versus 7.3 percent), to be obese (3.3 percent
versus 2.6 percent) and to have immune conditions (3.2 percent versus 1.6
percent). But significantly fewer young women smoked, which resulted in overall
medical vulnerability of 29.7 percent compared with 33.3 percent for young men.
Co-Authors: M. Jane Park, MPH, Jason Schaub, MPH, and Claire Brindis, DrPH, of UCSF.
Funding: The study is supported by grants from the Health Resources and Services Administration of the U.S. Department of Health and Human Services.