Inflammation in the body has been linked to the intensity of tobacco smoking among people with HIV, a new study suggests.

The researchers, including Krishna Poudel from University of Massachusetts at Amherst, reported positive linear relationships between intensity, duration and pack-years of smoking and inflammation in HIV-positive people. "While it is important to support and encourage people living with HIV to ultimately quit smoking, it is also important to suggest they reduce the frequency of smoking until they can fully quit," Poudel said. "That would also help their health status by reducing inflammation," he added, noting that a high level of inflammation is linked to a greater risk of disease and death in people living with HIV.

The team believes it to be the first, more thorough examination of specific smoking-related variables with the levels of inflammation in this group, while also taking into account highly active antiretroviral therapy (HAART) and other important factors. For the study, published in the journal AIDS and Behavior, the researchers interviewed 284 study participants, gathering details about their smoking and medical history and other relevant information, such as whether they were receiving HAART. They asked about how many cigarettes were smoked per day (intensity) and for how many years (duration). Lifetime smoking exposure was gauged in pack-years, which is determined by multiplying the number of packs smoked daily by the number of years the person has smoked.

The team then measured serum C-reactive protein (CRP), a pro-inflammatory biomarker, and several strong predictors of inflammation in the participants. The researchers found similar results for smoking duration and pack-years of smoking; that is, participants who had smoked for longer periods and those who had greater pack-years were more likely to have high levels of CRP than those who had smoked for shorter periods and had fewer pack-years.