Publications

Publications

Monocyte and T cell immune phenotypic profiles associated with age advancement differ between people with HIV, lifestyle-comparable controls and blood donors.

Monocyte and T cell immune phenotypic profiles associated with age advancement differ between people with HIV, lifestyle-comparable controls and blood donors.

Authors

De Francesco D, Sabin CA, Reiss P, Kootstra NA.

Lay summary

People with HIV who are successfully treated show some signs of premature aging and may be more likely to experience clinical conditions.   It has been suggested that HIV may contribute to this through the immune dysfunction and inflammation that it causes.  In a previous study we used a set of markers in the blood to generate an aging score for each person.  In this study, we studied associations between these scores and several immunological markers among participants in the COBRA cohort.  We found that ‘age advancement’ (a score that would predict an older age than someone’s true age) was associated with distinct patterns of blood markers, some of which were also seen in blood donors who were uninfected with HIV.  Among people with HIV, associations with age advancement were also seen with immune recovery after antiretroviral treatment.  The findings suggested, however, that a range of factors (including some unrelated to HIV) may contribute to the ageing process in people with HIV.

Research theme

Sleep disorders in human immunodeficiency virus: a substudy of the Pharmacokinetics and Clinical Observations in PeoPle over fifty (POPPY) Study.

Sleep disorders in human immunodeficiency virus: a substudy of the Pharmacokinetics and Clinical Observations in PeoPle over fifty (POPPY) Study.

Authors

Kunisaki KM, De Francesco C, Sabin CA, Winston A, Mallon PWG, Anderson J, Bagkeris E, Boffito M, Doyle N, Haddow L, Post FA, Sachikonye M, Vera J, Khalil W, Redline S.

Lay summary

We know that many people with HIV report problems with their sleep.  However, the existing literature on sleep problems in this group is extremely limited. We asked participants in the POPPY-Sleep study to complete questionnaires that would assess whether they were likely to have insomnia or restless legs syndrome (RLS), and measured whether they had sleep apnea (SA).  Of the 357 people with HIV in the study, 21% had insomnia, 13% had RLS and 6% had SA.  Insomnia was over five times more common in people with HIV than in the HIV-negative controls in the study, but RLS and SA didn’t appear to occur any more commonly in those with HIV.  People with HIV with insomnia had poorer quality of life.  Importantly, very few people with insomnia had been diagnosed by a doctor as having this, or were receiving treatment for their insomnia.  The findings from our study argue for better screening and advice for people with HIV about how to improve their sleep.

Research theme

Correlation between computerised and standard cognitive testing in people with HIV and HIV-negative individuals

Correlation between computerised and standard cognitive testing in people with HIV and HIV-negative individuals

Authors

De Francesco D, Underwood J, Anderson J, Boffito M, Post FA, Sachikonye M, Mallon PWG, Haddow L, Vera JH, Kunisaki KM, Sabin CA, Winston A.

Lay summary

There are different ways to measure whether a person has a problem with their brain.  In research studies, such as the POPPY study, the traditional approach is to use a method whereby we ask participants to complete tasks using pen and paper.  More recently, it has been possible to do similar assessments using a computer.  However, we don’t know if the results are similar from these two approaches.  A sub-group of POPPY participants has received both types of assessment.  We therefore investigated whether the results were broadly similar from these two different methods of assessment.  Overall, the two methods were broadly similar with moderate correlations between them.  As we might expect, correlations were stronger when the tasks intended to assess a similar brain process.  However, overall, when each tool was used to identify people who might have brain problems, the different approaches identified slightly different people.  Therefore, it appears that the two approaches may assess slightly different components of brain function. 

Sleep health and cognitive function among people with and without HIV: the use of different machine learning approaches

Sleep health and cognitive function among people with and without HIV: the use of different machine learning approaches

Authors

De Francesco D, Sabin CA, Winston A, Rueschman MN, Doyle ND, Anderson J, Vera JH, Boffito M, Sachikonye M, Mallon PWG, Haddow L, Post FA, Redline S, Kunisaki KM.

Lay summary

There are many different ways to measure sleep patterns.  Within the POPPY-Sleep study we measured sleep using several different approaches, including a technique known as actigraphy.  This technique monitors periods when a person is active or at rest, and uses a standard algorithm to convert the measurements obtained into a number of measures which summarise both the quantity and quality of a person’s sleep.  We currently don’t know which of the many measures generated are most strongly associated with brain function.   We investigated this in the POPPY-Sleep study.  We did not find any strong associations between either the amount of time a person slept or the proportion of time that they were asleep during the night and their brain function.  However, the average amount of time the person was awake whilst trying to sleep (rather than the actual time spent asleep) was associated with their brain function.  In addition, people whose sleep patterns were very irregular generally had poorer brain function.  Our findings suggested that it is sleep continuity and regularity which is more strongly associated with brain health rather than other simpler measures of sleep.

Research theme