Today, people who have HIV in the western world can live just as long as those who don't, so it’s easy to forget the hazards of the chronic illness.

Lighting up a cigarette, especially if it’s something you’ve always done, may not seem like a very big deal. But it is. Studies show that if you have HIV, the harmful effects of smoking are greatly magnified, even when the disease appears to be under control with medication.

Anti-smoking advocates wonder, with HIV now very manageable with antiretroviral drugs, why would anyone jeopardize their health by smoking? Why not just kick the smoking habit for good?

It’s easier said than done, especially since smoking is so entrenched in many niche communities of people with HIV. That’s why the U.S. Centers for Disease Control and Prevention (CDC) are urging people with HIV to quit, using the story of an HIV-positive man named “Brian” to get their message across.

Hit By a Stroke After Rebounding from HIV

Brian is one of many real people used in the CDC’s “Tips from Former Smokers” campaign. HIV was recently added to agency's list of chronic conditions to target with anti-smoking messages, including asthma, cancer, COPD, and cardiovascular disease. Pregnant women are also included in the social media push.

Pregnancy and Smoking: Why You Need to Quit »

Brian, 43, wound up in the hospital after being diagnosed with HIV. But soon, doctors had his disease under control. He rebounded, went back to work, and began to feel “invincible.” Quitting his three decade smoking habit was hardly a priority.

Then Brian had a stroke and nearly lost his life.

“We know from a large surveillance project running here that the prevalence of smoking among people with HIV in care is about 42 percent,” said Dr. John T. Brooks, an HIV specialist with the CDC.

That is twice the national average of 21 percent, Brooks told Healthline. “Smoking does impair CD4 cells in a way that can be bad for you," he said. "It increases the risk of certain pneumonias, for example.”

Null

CD4 T-cells, or “helper cells,” help the body fight infections like pneumonia. Pneumonia remains a leading cause of death among people who progress from HIV to AIDS. The level of CD4 cells in a person's body is a good indicator of whether their HIV is under control.

Recent studies also point to the role of inflammation in people with HIV. “Just having an HIV infection produces a chronic state of inflammation,” Brooks said.

Inflammation is already linked to other conditions that affect smokers, such as heart disease, lung disease, certain cancers, and low bone density and fragility fractures. “If you have HIV and smoke, you’re getting hit from both directions with this inflammatory problem,” Brooks said.

Just How Dangerous Is Smoking If You’re HIV-Positive?

It’s well established that smoking can cause an early death, and HIV can too. But combine the two, and the deadly punch is much more powerful.

In fact, in a Danish study in which patients got top-of-the-line HIV care including free antiretroviral medication, HIV-positive smokers lost more years of life from smoking than from HIV.

In the study, a person with HIV lost five years of life to the disease. A smoker without HIV lost almost four years of life to smoking. But a person with HIV who also smoked lost a total of 12 years of life, not nine, as one might think.

"If a person's HIV is under control, the risk of smoking remains and becomes a greater and often leading preventable risk for illness and death," Brooks said.

Ready to Quit? Here's How »

Why Do So Many People with HIV Smoke?

People with HIV are often part of demographic groups that have especially high rates of smoking, namely gay men and African-Americans.

People with HIV in the U.S. also tend to have less formal education and to come from poorer family backgrounds, Brooks said. They may also have issues related to substance abuse or mental illness. These factors are also linked to higher rates of smoking.

The smoking rate among gays and bisexuals in the U.S. last year was 27.7 percent, according to the CDC. That is compared to 17.3 percent among heterosexuals.

This can partly be blamed on aggressive marketing by the tobacco industry. In fact, when the pioneering HIV advocacy group ACT-UP boycotted Philip Morris in 1990, the tobacco giant won gay customers back by pledging large sums of money to fight AIDS.

Timeline: What Happens When You Quit Smoking? »

HIV Patients Want to Quit

Surveys have shown that two-thirds of people with HIV who smoke want to quit, according to AIDS.gov. But it is a difficult habit for anyone to kick.

Brooks said doctors can help by initiating conversations with their patients about quitting. The problem is that HIV specialists usually are not trained to provide that kind of care.

"If a person's HIV is under control, the risk of smoking remains and becomes a greater and often leading preventable risk for illness and death." — Dr. John Brooks

There is currently a shift, however, toward people with HIV getting care from doctors in family and general practice. While the move toward primary care providers has some HIV experts concerned about the care patients will receive, in some ways it could be beneficial.

“Smoking cessation is a cornerstone of their training,” Brooks said of primary care doctors. “Now they can be in a care setting where providers pay a lot more attention with the other things in your life.”

Care from a primary care physician always can be “backed up by a specialist when things get tough,” Brooks added.

Brooks hopes more doctors who treat people with HIV will start to provide smoking cessation counseling. He encouraged them to look into levels of reimbursement for these services.

The Affordable Care Act requires insurance providers who sell plans on state and federal exchange websites to offer smoking cessation counseling without any out-of-pocket co-payment from the patient.

Read More: ACA Brings Mental Health, Substance Abuse Treatment to Millions »

CDC Program Drives Smokers to Quit

The good news is that the CDC’s “Tips from Former Smokers” campaign is working.

A paper published last year in The Lancet found that after only 12 weeks of the campaign, an estimated 1.64 million Americans had tried to quit, with an estimated 100,000 presumed successful. About 6 million non-smokers also talked to friends and family about the dangers of smoking.

Calls to the CDC’s 1-800-QUIT-NOW hotline rose by 75 percent during the 2013 "Tips" campaign, and visits to the website increased 38-fold.

Brooks said that with few exceptions, most smoking cessation medications do not interact with antiretroviral therapy. He concedes that people with HIV are under a lot of stress, which makes quitting smoking even more difficult.

But he remains hopeful. “They may say, ‘This is the only way I can release my stress, it’s my last bad habit,’" Brooks said. "But it’s not an argument that’s hard to win when you remind them of the damage smoking is doing to them.”

Star Power: Celebrities Who Quit Smoking »