(RxWiki News) One type of sleeping pill can treat several other conditions, like insomnia, epilepsy and anxiety. But it may also weaken the immune system.
A recent study found benzodiazepines are linked to a higher risk for pneumonia. Pneumonia patients taking benzodiazepines are also at higher risk for death, the study found.
This group of sedatives are very common in the US. About 2 percent of the US population have taken them for a year or more. But researchers are now learning more about their possible risks.
"Take medications only as directed."
The study, funded by Eneanya Obiora of the Division of Epidemiology and Public Health at the University of Nottingham in the United Kingdom, relied on a national database with over nine million patients' records. First, the researchers located 4,964 patients who were diagnosed with pneumonia between 2001 and 2002 and compared them to 29,697 patients without pneumonia.
Each pneumonia patient was matched to six non-pneumonia patients in the same practice who had the same age and gender as the pneumonia patient. The patients were matched only for age and gender though, so there were other significant differences between the two groups. The pneumonia patients were more likely to be smokers and more likely to have had pneumonia in the past.
The pneumonia patients were also more likely to have had underlying conditions and/or a serious illness, such as heart attack, depression or another mental disorder.
Then the researchers looked at how many patients in both groups had taken benzodiazepines or zopiclone, a similar drug, recently, presently or in the past.
The researchers found that those who had taken benzodiazepines or zoplicone were about 54 percent more likely to contract pneumonia. The researchers took into account the differences in smoking status, previous infections and underlying conditions in their calculations.
However, because of the significant differences between the two groups at the start, it may not be possible to fully account for in these kinds of calculations.
When the researchers looked at specific individual medications, they found a link between catching pneumonia and use of diazepam (Valium), lorazepam (Ativan) and temazepam (Restoril). They did not find a link for chlordiazepoxide (Librium).
The researchers' analysis also found patients who had pneumonia were slightly more likely to die of the disease if they were taking benzodiazepines.
Pneumonia patients taking benzodiazepines were 22 percent more likely to die within a month and 32 percent more likely to die within three years. This link was found for all four of the specific medications.
This study did not show that benzodiazepines cause pneumonia or an early death. The link could be due to many reasons, and the researchers suspect the benzodiazepines weaken the immune system. Past research has shown a link between this class of medications and a higher risk of infection and death from blood poisoning in critically ill patients.
The study was published December 5 in the journal Thorax. The research was funded by the Medical Research Council in the UK, the GSK/British Lung Foundation Chair of Respiratory Epidemiology (one author) and university department funding. One author received an honorarium from Hospira for a talk given to an organization.