Substance Use Among TB Patients Makes Treatment More Difficult
An article published in the January 26 issue of the Archives of Internal Medicine reports that about one in five tuberculosis patients in the United States abuse alcohol or use illicit drugs. It appears that these patients are more contagious and difficult to treat.
The annual tuberculosis (TB) incidence in the United States is among the lowest in the world at 4.6 cases per 100,000 people. Even so the risk of TB continues to be higher among certain groups which include ethnic minorities, immunocompromised people, those who have a history of homelessness, and foreign-born persons.
A less frequently discussed group that complicates US tuberculosis control efforts is the illicit drug–using and alcohol-abusing population. This study looked at the prevalence of substance abuse among tuberculosis cases reported in the United States.
John E. Oeltmann, Ph.D., of the Centers for Disease Control and Prevention, Atlanta, and colleagues analyzed data from 153,268 patients 15 years or older who were reported to have TB between 1997 and 2006. Of these, 18.7% (28,650) reported substance abuse. This is a larger percentage than those who reported any other established risk factors for TB, including recent immigration to the United States (12.9 percent), infection with HIV (9.5 percent), living in a group setting (6.6 percent), homelessness (6.3 percent) or working in a high-risk occupation (4.3 percent).
Among patients who were negative for HIV, those who reported substance abuse were 1.8 times more likely to have a more contagious form of TB (as indicated by a positive sputum smear). Females who were substance abusers were 2.4 times more likely to experience treatment failure than were other females.
The results suggest that substance abuse is the most commonly reported modifiable behavior that impedes tuberculosis elimination efforts in the United States. Oeltmann and colleagues found that approximately 1 in 5 patients with TB either use an illicit drug, drink alcohol to excess, or both. In US born patients with TB, the ratio is nearly 1 in 3.
The prevalence of substance abuse among patients with TB varies greatly according to country of birth, sex, and race. Substance abuse among patients with TB is most prevalent among the US-born (29.0%), male (32.8%), and black (39.0%) patients. Prevalence of substance abuse was also relatively high among white (26.2%) and Hispanic (22.7%) patients.
The researchers suggest that the relationship between substance abuse and increased transmission of Mycobacterium tuberculosis can be explained in several ways:
* Patients who abuse substances are less likely to be screened for tuberculosis
* Patients who abuse substances are less likely to begin and complete treatment for latent infection or active disease
* Patients who abuse substances often have compromised immune systems or nutrition deficits
* Antituberculois medications are usually metabolized by the liver which is often damaged (ie cirrhosis) by the substance abuse.
I would concur with the authors who conclude, "Tuberculosis control and substance abuse programs need to work together to simultaneously treat the diseases of addiction and TB.”
This study was funded by the Centers for Disease Control and Prevention, Division of Tuberculosis Elimination. Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.
Tuberculosis and Substance Abuse in the United States, 1997-2006; Arch Intern Med. 2009;169:189-197.; John E. Oeltmann, PhD; J. Steve Kammerer, MBA; Eric S. Pevzner, PhD; Patrick K. Moonan, DrPH