Copenhagen comorbidity in HIV infection (COCOMO) study: a study protocol for a longitudinal, non-interventional assessment of non-AIDS comorbidity in HIV infection in Denmark

Abstract

BackgroundModern combination antiretroviral therapy (cART) has improved survival for people living with HIV (PLWHIV). Non-AIDS comorbidities have replaced opportunistic infections as leading causes of mortality and morbidity, and are becoming a key health concern as this population continues to age. The aim of this study is to estimate the prevalence and incidence of non-AIDS comorbidity among PLWHIV in Denmark in the cART era and to determine risk factors contributing to the pathogenesis. The study primarily targets cardiovascular, respiratory, and hepatic non-AIDS comorbidity.Methods/designThe Copenhagen comorbidity in HIV-infection (COCOMO) study is an observational, longitudinal cohort study. The study was initiated in 2015 and recruitment is ongoing with the aim of including 1500 PLWHIV from the Copenhagen area. Follow-up examinations after 2 and 10 years are planned. Uninfected controls are derived from the Copenhagen General Population Study (CGPS), a cohort study including 100,000 uninfected participants from the same geographical region. Physiological and biological measures including blood pressure, ankle-brachial index, electrocardiogram, spirometry, exhaled nitric oxide, transient elastography of the liver, computed tomography (CT) angiography of the heart, unenhanced CT of the chest and upper abdomen, and a number of routine biochemical analysis are uniformly collected in participants from the COCOMO study and the CGPS. Plasma, serum, buffy coat, peripheral blood mononuclear cells (PBMC), urine, and stool samples are collected in a biobank for future studies. Data will be updated through periodical linking to national databases.DiscussionAs life expectancy for PLWHIV improves, it is essential to study long-term impact of HIV and cART. We anticipate that findings from this cohort study will increase knowledge on non-AIDS comorbidity in PLWHIV and identify targets for future interventional trials. Recognizing the demographic, clinical and pathophysiological characteristics of comorbidity in PLWHIV may help inform development of new guidelines and enable us to move forward to a more personalized HIV care.Trial registrationClinicalTrials.gov: NCT02382822.Electronic supplementary materialThe online version of this article (doi:10.1186/s12879-016-2026-9) contains supplementary material, which is available to authorized users.

Airflow limitation in people living with HIV and matched uninfected controls

“…The COCOMO study has been described elsewhere 15. In brief, the COCOMO study (NCT02382822) is a prospective study evaluating prevalence, incidence and pathogenesis of non-AIDS comorbidity in PLWHIV in Copenhagen, Denmark.…”

“…The procedure and calibration of spirometry have previously been described 15. Briefly, an EasyOne ultrasonic spirometer (ndd Medical, Zürich, Switzerland) was used in accordance with American Thoracic Society/European Respiratory Society guidelines.…”

“…In this cross-sectional study we evaluate the prevalence of airflow limitation and associated risk factors in a large cohort of PLWHIV from the Copenhagen Co-morbidity in HIV infection (COCOMO) study and matched uninfected controls from the Copenhagen General Population Study (CGPS) 15. Uniform data collection in these cohorts and detailed information on risk factors enabled us to more accurately explore the association between HIV and pulmonary function.…”

HIV infection is independently associated with a higher concentration of alpha‐1 antitrypsin

“…Information about HIV‐related variables, including current and nadir CD4 T‐cell counts, was retrieved from patient records. All participants completed an identical comprehensive questionnaire, which included detailed information on tobacco exposure, as previously described .…”

“…We used cross‐sectional data from PLWH enrolled in the Copenhagen Comorbidity in HIV Infection (COCOMO) study and age‐ and sex‐matched uninfected controls from the Copenhagen General Population Study (CGPS). The COCOMO study is a prospective cohort study evaluating the prevalence, incidence and pathogenesis of non‐AIDS‐related comorbidity in PLWH in Copenhagen, Denmark . CGPS was initiated in 2003 and follows > 100 000 adults from the greater Copenhagen area.…”