Comorbidity in the aging HIV population of the UK: a CPRD analysis.

Date of ISAC Approval: 
23/02/2016
Lay Summary: 
Life expectancy in patients with human immunodeficiency virus (HIV+ve patients) is now greatly improved due to the availability of potent combined medical treatments, resulting in an aging HIV+ve population in developed countries. The demographic shift to an older surviving population has been accompanied by a decline in illness and death owing to HIV infection and a concomitant rise in the proportion owing to non-HIV diseases, including age-related disease (co-morbidities). There is evidence that HIV itself increases the risk of developing some types of age-related disease particularly heart disease. This study is designed to provide evidence to aid general practitioners and secondary care professionals understand the likely co-morbidities to be found in an aging HIV+ve population and thus facilitate future shared care between the two systems. Patients will be compared to patients without HIV of similar age, to assess rates of current co-morbidities, and to follow patients for up to ten years to assess the development of new diseases. Finally the study will evaluate risk factors for the development of chronic diseases in HIV+ve patients.
Technical Summary: 
The primary objectives in this three-part retrospective matched cohort database study of HIV+ve patients and matched controls (HIV-) are to: i) evaluate the prevalence of non-HIV related co-morbidities in HIV+ patient's compared to HIV- patients; ii) compare incidence of diseases over time; iii) identify risk factors for incident disease onset. Observation is from January 1st 2004 until December 31st 2014. Follow up is for a decade in 24 month epochs (x5). Outcomes are clinical and demographic characteristics at index date and over time, plus major co-morbidities reported per epoch with particular interest in cardiovascular disease (CVD); diabetes; neuro-psychiatric disease; respiratory diseases; primary neoplasms; non-hereditary renal disease plus hepatic and blood dyscrasias. Analyses will be: a) cross-sectional descriptive analyses of HIV+ and HIV- clinical characteristics and comorbidity diagnoses in the years 2004 and 2014; b) longitudinal follow up of patients describing prevalent co-morbidities and new diagnoses over the 10 year period; c) modelling risk factors for co-morbidity incidence over ten years follow-up including HIV status, age and interaction between the two. Individual repeated measures models will be developed for the four diseases that have the highest prevalence.
Health Outcomes to be Measured: 
Prevalence of non-HIV related co-morbidities in HIV positive patient's compared to HIV negative patients Comparison of disease rates over ten years Risk factors for non-HIV related comorbidities in HIV positive patients
Collaborators: 

Dr Louise Watson - Chief Investigator - EpiPharmaCo
Eilish McCann - Collaborator - Merck & Co., Inc.
Ruth Farquhar - Collaborator - Exploristics
Ryan Dillon - Collaborator - Merck Sharp & Dohme - UK