STI clinic attendees have high HIV diagnosis rates in Netherlands, but many missed opportunities in primary care

Two studies from the Netherlands show that while the proportion of people with HIV who are diagnosed has improved in recent years, the Netherlands lags behind some other western European countries in its HIV diagnosis rate, which has not improved at all in some groups.

Diagnosis rates in 2012 were high in gay men and other men who have sex with men (MSM – only 14% of those with HIV undiagnosed) and non-migrant heterosexuals (16% undiagnosed) who attended sexual health clinics. However, they were considerably lower among MSM who did not visit sexual health clinics (about 35% undiagnosed), among African migrants visiting sexual health clinics (46% undiagnosed) and among migrants who did not visit sexual health clinics (about 50% undiagnosed).

The lowest rates of diagnosis were in female sex workers, in whom two-thirds of those with HIV did not know they had it. The researchers comment that this is often because female sex workers are undocumented or otherwise hard-to-reach immigrants who may only stay in the Netherlands for a short time.

Glossary

matched

In a case-control study, a process to make the cases and the controls comparable with respect to extraneous factors. For example, each case is matched individually with a control subject on variables such as age, sex and HIV status. 

syphilis

A sexually transmitted infection caused by the bacterium Treponema pallidum. Transmission can occur by direct contact with a syphilis sore during vaginal, anal, or oral sex. Sores may be found around the penis, vagina, or anus, or in the rectum, on the lips, or in the mouth, but syphilis is often asymptomatic. It can spread from an infected mother to her unborn baby.

shingles

Condition caused by a herpes virus infection, involving painful blisters on the skin.

 

lymph nodes

Bean-sized structures throughout the body's lymphatic system, where immune cells congregate to fight infections. Clusters of lymph nodes are found in the underarms, the groin, and the neck.

lymphadenopathy

A swelling of the lymph nodes.

A second study, of people attending six primary care practices in Amsterdam, found that the majority of people eventually diagnosed with HIV had attended their GP more than once in the year before their diagnosis and had more appointments and blood tests than a control group of matched patients who were not living with HIV. They were also vastly more likely than control patients, in the five years before diagnosis, to have been diagnosed with a sexually transmitted infection (STI) or at least one of a list of HIV-related diseases and symptoms. The most common single condition associated with subsequent HIV diagnosis was unexplained weight loss.

The researchers of this paper say that “there is an urgent need to identify the barriers and facilitators that affect effective implementation by GPs…of HIV indicator condition-guided testing in primary care.”

Changing patterns of HIV prevalence and diagnosis in the Netherlands

The first study compared the absolute number of people with HIV in different groups, HIV prevalence in those groups, and the proportion who were undiagnosed in each group, in 2007 and 2012, using national data sources including the ATHENA cohort, which captures data on most Dutch HIV patients.

During the five years from 2007 to 2012, it is estimated that the absolute number of people aged 15 to 70 living with HIV in the Netherlands, diagnosed and undiagnosed, increased from approximately 21,360 to 24,350, a 14% increase. This was largely accounted for by a 33% increase in MSM: 15,590 MSM are now thought to be living with HIV.

Among MSM who did attend sexual health clinics, HIV prevalence fell, from 21.1% to 15.5%. This may show that more testing means that men at somewhat lower risk of HIV are coming forward to test.

However, the large majority of MSM did not attend a sexual health clinic in the last year, including an estimated 12,000 or more MSM with HIV. Estimated HIV prevalence in non-attendees increased, from 4.0% to 7.5%.

The second-largest group of people living with HIV were migrants. In the Netherlands, while the majority of HIV-positive migrants came from sub-Saharan Africa (3760 people, representing an estimated 2.3% of all immigrants from sub-Saharan Africa), a significant minority came from the substantial population of Caribbean and Surinamese people in the country. The prevalence in this group is 0.3%, which is somewhat higher than in the general population.

In 2012, prevalence in sub-Saharan African people was essentially the same among sexual health clinic attendees and non-attendees (around 2.4%). Since 2007, HIV prevalence among sexual health clinic attendees almost halved, from just under 5% in 2007, but fell little in non-attendees.

Other populations in the Netherlands either have low prevalence or are small in number. In 2012, it is estimated that there were just 350 HIV-positive female sex workers in the Netherlands, representing 1.6% of the population of female sex workers, and even fewer HIV-positive people who inject drugs.

As mentioned above, the Netherlands has rather higher rates of undiagnosed people with HIV than some other high-income European countries. In 2012, it is thought that 34% of people with HIV (and the same proportion of gay men with HIV) were undiagnosed, compared with approximately 24% in the UK and 18% in France – though the Netherlands rate is comparable with Germany. This is an improvement since 2007, when nearly 40% were undiagnosed. The situation is much better among sexual health clinic attendees, with only 14% of gay men and 16% of non-migrant heterosexuals who attended sexual health clinics undiagnosed – in the latter case, this has fallen from 27% in 2007.

However, it is estimated that 48% of sub-Saharan African people in the Netherlands were undiagnosed and this appears not to have changed significantly since 2007. As noted above, two-thirds of the small group of HIV-positive sex workers were undiagnosed.

There were very large regional differences. In Amsterdam, only 14% of people with HIV in general and 9% of MSM were undiagnosed: in the rest of the Netherlands it was still around 40%, even in MSM.

The researchers note that despite improvements in diagnosis rates in sexual health clinic attendees, rates in general have not fallen and that “Besides STI clinics, GPs could have a more active role in the detection of HIV, as recently put forth in the Dutch guidelines on STI testing for GPs.”

Missed opportunities for HIV testing by Amsterdam GPs

Another study looked at 102 HIV cases diagnosed at six GP practices in Amsterdam between 2002 and 2012 to see if there had been missed opportunities for earlier diagnosis.

The conclusion is that many opportunities were missed. During the timespan of the study, 62% of people subsequently diagnosed with HIV had visited their GP in the year before diagnosis, compared with 39% of a matched group of HIV-negative people.

The researchers looked at the frequency of indicator conditions for HIV testing, as specified in the Dutch GP guidelines. They compared the frequency of these conditions in people later diagnosed with HIV with their frequency in HIV-negative people. The indicator conditions were split between STIs (ranging from gonorrhoea to hepatitis C), HIV-related conditions like shingles or oral candida, and unexplained symptoms also associated with HIV, such as unexplained chronic diarrhoea.

In the five years prior to HIV diagnosis, 59% of people with HIV reported at least one indicator condition compared with 7% of control patients. The conditions most likely to be reported in people with HIV were syphilis, chlamydia, unexplained weight loss, pneumonia, symptoms similar to mononucleosis (EBV or ‘glandular fever’), shingles and swollen lymph nodes.

Compared with HIV-negative people, unexplained weight loss was 40 times more likely to be reported in people later diagnosed with HIV, syphilis 39 times more likely, lymphadenopathy 30 times more likely, gonorrhoea 16 times time more likely, and peripheral neuropathy also 16 times more likely. Subsequent HIV diagnosis, compared with not having HIV, was associated with a twelvefold risk of having had one indicator condition, and a 77-fold risk of having had more than one.

Some of these indicator conditions would indicate current infection with HIV; others, such as the STIs, might indicate imminent risk. People later diagnosed with HIV were 40 times more likely to have been diagnosed with two or more STIs in the five years prior to diagnosis than HIV-negative controls.

Between 2002 and 2012, HIV prevalence in people at the six practices increased from 0.4% to 0.9%, and in two practices to 1.5% – well above the 0.2% recommended by the British HIV Association as defining a high-prevalence area.

“This study revealed many opportunities for HIV indicator condition-guided testing in primary care,” the authors write. “At this stage however, [these] conditions are not exploited as triggers for HIV testing. To move from policy to practice, there is an urgent need to address the barriers and facilitators that affect effective implementation by GPs.”

References

Op de Coul ELM et al. Changing patterns of undiagnosed HIV infection in the Netherlands: who benefits most from intensified HIV test and treat policies? PLOS ONE 10(7): e0133232. doi: 10.1371/journal.pone.0133232. See full text here. 2015.

Joore IK et al. HIV indicator condition-guided testing to reduce the number of undiagnosed patients and prevent late presentation in a high-prevalence area: a case-control study in primary care. Sexually Transmitted Infections, early online publication. doi: 10.1136/sextrans-2015-052073. See abstract here. 2015.