Most health problems in people living with HIV in two large
cohorts can be classified in six clusters, with cardiovascular disease,
metabolic problems, sexually transmitted infections and mental health
conditions being the most common in Britain, Ireland and the Netherlands,
according to research published in the journal Open Forum Infectious
Diseases
 last month.

The clusters identified in the study reveal the major
non-HIV medical needs of people living with HIV, especially older adults, and
the needs for prevention of ill health.

Findings from the study were also presented at the
Conference on Retroviruses and Opportunistic Infections (CROI) in Seattle earlier this
month.

Two cohorts were analysed in the study, which was designed
to detect patterns in potentially preventable co-morbidities in people living
with HIV and to provide information to help better targeting of interventions
and a better understanding of shared pathophysiology of co-morbidities.

The POPPY cohort consisted of 699 people with HIV aged 50 or
over and 374 younger people with HIV, receiving care in the United Kingdom and
Ireland. Eighty-five per cent of the cohort was male, the median age was 52, 15.9% were black
African, and 76% were men who have sex with men. Participants had been living with
HIV for a median of 13.2 years, 97.5% were on antiretroviral treatment and
89.9% had a viral load below 50 copies/ml. The median age in the over-50
segment of the cohort was 57 years and duration of HIV infection was slightly
longer (15.8 years) but in other respects the older segment was demographically
similar to the overall cohort.

The AGEhIV cohort consisted of 598 people living
with HIV aged 45 and over receiving care in the Netherlands. Demographic
characteristics and HIV history were very similar to the overall POPPY cohort.

Co-morbidities were captured through a structured interview
cross-checked against medical records. There were a few differences in the list
of co-morbidities asked about in the two cohorts.

The most common single co-morbidities in POPPY were
gonorrhoea (42.6%), syphilis (30.4%), depression (32.4%) and dyslipidaemia
(27.3%). In AGEhIV the most common co-morbidities were hypertension
(43.1%), osteopenia/osteoporosis (42.6%), lipodystrophy/lipoatrophy (32.1%) and
candidiasis (31.9%). In both cohorts, people reported a median of five co-morbidities.

The researchers analysed the relationship between
co-morbidities to identify conditions that are more likely to occur together in
the same person than would be expected by chance alone. In the POPPY cohort,
they identified six clusters:

  • cardiovascular (angina, coronary
    bypass surgery, heart attack, heart failure, high blood pressure, peripheral
    vascular disease, end stage kidney disease)
  • sexually transmitted diseases
    (gonorrhoea, lymphogranuloma venereum [LGV], chlamydia, hepatitis C)
  • mental health (depression,
    anxiety, panic attacks)
  • cancers (blood cancers, skin
    cancer, solid organ cancer)
  • metabolic (abnormal lipids,
    lipodystrophy, high blood pressure)
  • chest and other infections (cytomegalovirus [CMV],
    pneumonia, dizziness/vertigo, asthma/bronchitis/chronic obstructive pulmonary disease [COPD], chest infection).

Similar clusters were seen in AGEhIV.

Moreover, in the POPPY study:

  • People with a higher burden of
    cardiovascular disease tended to have a lower burden of sexually transmitted
    infections, and vice versa.
  • Depression was associated with
    sleeping problems and irritable bowel syndrome.
  • Greater severity of mental health
    problems was strongly associated with severity of all other health patterns,
    but especially cancers and chest and other infections.
  • In the older people in the
    POPPY cohort, greater cardiovascular disease severity was associated with
    greater severity of mental health, metabolic and asthma scores.
  • In older individuals, panic
    attacks were associated with asthma/bronchitis/COPD.

In the AGEhIV study:

  • Cardiovascular disease was most
    strongly associated with a past history of AIDS-defining conditions.
  • Depression was associated with
    neurological problems such as dizziness/vertigo.
  • More severe general health
    problems were strongly associated with greater severity of cardiovascular
    disease, chest or liver disorders, and mental health or neurological problems.

The investigators say that their findings demonstrate that
“comorbidities do not co-occur at random, and in general, are likely to cluster
in specific patterns, some which are consistent across different cohorts.”

Although some of the clusters – such as cardiovascular
disease and metabolic problems – are well recognised and have common
pathologies, other patterns are less well established, they say. The strong
association between mental health and neurological problems deserves more
investigation, as do the associations between mental health disorders and
cardiovascular disease, metabolic problems and sexually transmitted infections.

Looking at the POPPY cohort alone, the researchers also
found that different co-morbidity clusters were associated with different risk
factors. For example, prior AIDS was associated with cardiovascular disease,
mental health problems, cancers and chest or other infections, but not with
metabolic problems. People with a history of injecting drug use, who formed
about 10% of the cohort, were less likely to have co-morbidities except for
mental health problems or sexually transmitted infections.

Surprisingly, current or former smoking was not associated
with any co-morbidity cluster, and nor was nadir CD4 cell count.

Image: Graphic from the study showing significant nonrandom associations between co-morbidities in the POPPY cohort.