Which health conditions are more or less common in people with HIV?

A cross-sectional study of patients in UK health services has compared the prevalence of a large number of different health conditions in people with HIV, versus those without HIV. Most findings confirm previous research, but the study also found a lower prevalence of many cardiovascular conditions and rheumatoid arthritis in people with HIV, while infertility, bipolar disorder and numerous infections were more common.

The study, by Dr Daniel Morales and colleagues at Dundee University, looked at anonymised patient data from the UK Clinical Research Database GOLD, which contains de-identified electronic primary care records, plus data on hospitalisation from the Hospital Episodes Statistics database.

The researchers only looked at records completed up to a specific date – 30 November 2015. The reason to choose a date nearly seven years ago was to ensure completeness and anonymity of data, but it means that conditions acquired since then and subsequent outcomes (from recovery to death) were not included.

In total 942,077 records were included, representing 1.8% of the UK population under 18. Of these, 964 had HIV. To correct for likely under-representation, the researchers also crosschecked with Office for National Statistics data up to 2021 that retrospectively mentioned HIV diagnoses made before the 30 November 2015 date. Nonetheless, the 0.1% HIV prevalence recorded is lower than the actual prevalence of HIV in over-18s in the UK (1.9%) which could mean that the prevalence of some conditions could be over- or underestimated.

The people without HIV were evenly balanced between men and women, whereas 61% of those with HIV were men. While a quarter of the HIV negative people were aged at least 65, only 7% of the people with HIV were. Though the figures below are adjusted for sex and age, the lack of older people in the HIV-positive group make the figures for age-related conditions less reliable.

The researchers grouped together 304 diagnosis codes into 47 groups of health conditions. Examples of groups range from ones that are extremely common (such as high blood lipids, recorded in about 40% of people) or mental health/neurological issues (in about 35%) to rarer ones such as central nervous system infections like meningitis (in less than 0.2% of people) and respiratory cancers such as lung cancer (in less than 0.5%).

The study found that the people with HIV were no more likely, or in some cases less likely, to have the most common groups of conditions. However it found that they were more likely to have rarer conditions. In the main these rarer conditions were infections – suggesting the influence of impaired immunity in people with HIV.

There were only two groups of conditions in the top 50% most prevalent ones, that people with HIV were more likely to have than HIV-negative people. Acquired blood abnormalities like anaemia or low white cell count were twice as likely in people with HIV as in HIV-negative people, but this is not surprising. There was also a catch-all group called ‘infections – other’, which were four times more likely in people with HIV.

On the other hand, several common conditions were less likely in people with HIV, including high blood pressure (22% less likely), asthma (35% less likely), and bone and joint disorders (44% less likely).

But several rare groups of conditions were very much more likely in people with HIV. The rarest group of conditions was fungal infections. Only 479 fungal infections were recorded in all subjects – a prevalence of 0.05% or one case in just under 2000 people. But 47 of these cases were seen in the 964 people with HIV in the study – a prevalence of 4.9%, or more than one case in 20. This means that fungal infections were 121 times more common in people with HIV than in people without it, when adjusted for age and sex.

Tuberculosis was also much more common in people with HIV: prevalence was 0.6% in all patients, but nearly 7% in people with HIV, meaning it was 13.5 times more likely. Other conditions more than five times more likely in people with HIV than in HIV negative people were immune disorders (7.4 times more likely) and gastro-intestinal infections (5.7 times more likely). Also viral infections, which as a group were 7.7 times more likely, but this was influenced by the specifically much greater prevalence of viral hepatitis (22 times more likely). Again, none of these findings were especially surprising.

In absolute numbers, some other conditions – such as high blood lipids – were much more common. The 399 cases of high blood lipids in people with HIV contrasts with the 50 viral infections, for example. But the prevalence of high lipids was not significantly higher than in people without HIV. Most other conditions related to cardiovascular disease were less common in people with HIV including atrial fibrillation (63% less likely) and coronary artery disease (48% less likely) but pulmonary embolism, (a blood clot in the lungs), was twice as common.

There were some other surprises when it came to individual conditions. For instance, rheumatoid arthritis was only a quarter as common in people with HIV as in people without it, even though autoimmune processes are involved in both. The more common form of arthritis, osteoarthritis, was also only about a third as common, and other bone/joint problems such as carpal tunnel syndrome and wrist fracture were also less common.

People with HIV were more likely to suffer from conditions influenced by low levels of sex hormones (male and female infertility and erectile dysfunction were all about twice as likely to be recorded in people with HIV), but only half as likely to suffer diverticulitis or gall bladder inflammation.

Certain cancers, as is well known, were more common in people with HIV – to the degree that they are already AIDS-defining conditions. These included non-Hodgkin’s lymphoma (12 times as common), Hodgkin’s lymphoma (4.7 times as common), and cervical cancer (4.6 times). But it was notable that no other cancers were recorded more often in people with HIV.

The other set of conditions significantly more common in people with HIV were a reminder of the psychological burden of having the disease. Bipolar disorder was 2.9 times more common in people with HIV than in HIV negative people, drug dependency 2.45 times as common, alcohol dependency 64% more common and depression 45% more common. So were the neurological conditions Bell’s palsy (three times as common) and peripheral neuropathy (79% more common – some of this may be related to treatment side effects).

One limitation of the study, which the researchers mention and which could lead to both co-morbidities and HIV  being under-recorded, is that many people with HIV get their healthcare primarily from hospital HIV clinics rather than GPs – and this would have been more the case in 2015 than it is now.

“In order to assure holistic care,” they write, specialist and primary care providers need close integration in the particular context of the UK, where HIV care is exclusively delivered by secondary care.”