HIV Weekly - 12th June 2013

Stopping smoking

People living with HIV who smoke are more likely to quit if they receive mobile phone support, the latest research from the United States shows.

Rates of smoking are much higher among people living with HIV, compared to the general population. This is especially concerning as many diseases related to smoking, including cardiovascular disease, are now important causes of serious illness and death for people living with HIV.

Many smokers find it hard to quit.

Researchers in Texas wanted to see if counselling and support delivered using mobile phones would make it easier for people to stop smoking. They therefore designed a study involving 470 people living with HIV who were current smokers.

The study participants were divided into two equal groups. All received written information about stopping smoking and were told where they could obtain nicotine replacement therapy. Half were also given free mobile phones which were used to provide counselling over three months.

Rates of quitting were assessed after three, six and twelve months.

Tests at the twelve-month follow-up visit showed that people who received mobile phone support were over twice as likely not to have smoked cigarettes in the previous seven days than people who received the standard help to stop smoking.

Mobile phone support had the biggest effect during the first three months.

However, the overall proportion of people who stopped smoking was low – at three months only 12% of participants receiving mobile phone support had stopped, compared to just 3% of participants in the control group.

The researchers think these low rates were partly because very few people obtained nicotine replacement therapy. To put this 'quit rate' in context, a recent large trial showed that 30% of smokers who received nicotine replacement plus telephone support remained non-smokers after one year. Better interventions to help people with HIV stop smoking still need to be identified.

It’s also notable that the study population was very disadvantaged and there were high rates of depression (67%), harmful alcohol use (31%) and drug use (40%).

Have you given up smoking or are you trying to? We'd love to hear about what worked for you, and we might feature some of your inspiring stories in our In your own words webpages. Send us your tales of giving up to info@nam.org.uk.

HIV and cancer

Not starting HIV treatment until the CD4 cell count is low increases the risk of several cancers, new research shows.

Researchers in the United States looked at rates of AIDS-defining cancers and other non-AIDS-defining cancers in 11,500 people who started HIV treatment between 1996 and 2011.

People in the study had a low CD4 cell count when they started treatment – on average just 202 cells/mm³.

Each person was followed up for an average of three years, some for much longer. There were 457 cancer diagnoses.

Kaposi’s sarcoma (KS) was the most common AIDS-defining cancer. Anal cancer was the most common non-AIDS-defining cancer, and breast cancer was the most common non-AIDS-defining cancer in women.

Rates of KS were highest in the first six months after starting HIV treatment. They then fell sharply in the next six months, falling even further during the rest of the study.

In contrast, rates of non-AIDS-defining cancers increased with longer duration of treatment, and overall increased by 7% with each year of follow-up.

The researchers think this increase is most likely due to the natural ageing of the people they were studying.

A low CD4 cell count at the time HIV treatment was started was associated with an increased risk of KS during the early months of therapy, as well as an increased risk of lymphomas and cancers related to human papillomavirus (HPV).

The researchers believe their findings show the importance of starting HIV treatment promptly and the incorporation of regular cancer screening into routine HIV care.

Anal cancer

Two recent studies provide some reassuring information about the risk of anal cancer. HIV treatment that suppresses viral load to undetectable levels reduces the risk of anal cancer, research involving 29,000 men shows.

Although still rare, rates of anal cancer are much higher in people with HIV compared to the general population.

The total number of cases is low, but a number of studies have shown that diagnoses of anal cancer have increased since effective antiretroviral treatment became available. This is probably because people who have cell changes associated with certain strains of human papillomavirus (HPV) are living long enough for anal cancer to develop.

Researchers in the United States wanted to see if an undetectable viral load during HIV therapy reduced the risk of anal cancer.

They looked at the records of over 45,000 men who received care between 1985 and 2009.

Overall, rates of anal cancer were similar between men who had taken HIV treatment and men who had not.

The researchers then looked in detail at the risk factors for anal cancer for the 29,000 men (63% of the group) who had taken HIV treatment. There were 302 cases of anal cancer in this group.

Men with a current CD4 cell count above 500 had a lower risk of the cancer, compared to those with a CD4 cell count below 200. Having a higher nadir (lowest-ever) CD4 cell count was also associated with a lower risk of the cancer.

Viral load was also associated with the risk of anal cancer. Men with an undetectable viral load between 81 and 100% of the time during antiretroviral treatment had their risk of anal cancer reduced by half, compared to men whose viral load remained detectable.

The researchers believe their findings have important implications for HIV care, showing the importance of starting HIV treatment at higher CD4 cell counts and also of maintaining an undetectable viral load during therapy.  

Separate research has shown that the high-grade lesions that precede anal cancer are more likely to improve than progress.

The Australian research involved 570 men who received care between 2004 and 2011. Three quarters of these men were living with HIV. The men with HIV had an average CD4 cell count of 500 and 84% had an undetectable viral load.

The participants in the study were followed-up for an average of one year. Overall, 13% developed high-grade lesions.

Progression to a higher stage of pre-cancerous lesion was more common among men with HIV and was associated with a lowest-ever CD4 cell count below 200.

There were four new cases of anal cancer, and two of these patients already had high-grade pre-cancerous lesions.

Spontaneous improvement in disease was much more common, and was seen in up to 47% of participants.

Rates of improvement did not differ between the HIV-positive and HIV-negative men.

The researchers call for further studies to see which factors are associated with disease regression and to determine which groups have the highest risk of disease progression. This will enable treatment to be properly targeted.