Chronogram: an R package for data curation and analysis of infection and vaccination cohort studies.

Motivation: Observational cohort studies that track vaccine and infection responses offer real-world data to inform pandemic policy. Translating biological hypotheses, such as whether different patterns of accumulated antigenic exposures confer differing antibody responses, into analysis code can be onerous, particularly when source data is dis-aggregated.

Results: The R package chronogram introduces the class chronogram, where metadata is seamlessly aggregated with sparse infection episode, clinical and laboratory data.

Association of age at antiretroviral therapy initiation with CD4 + : CD8 + ratio recovery among virally suppressed people with HIV.

Objective: To investigate the association of age at antiretroviral therapy (ART) initiation with CD4 +  : CD8 + T-cell ratio in virally suppressed people with HIV on long-term ART, and to characterize potential CD4 +  : CD8 + ratio recovery in this population by age.

Design: A longitudinal study of people attending an HIV clinic at the Royal Free Hospital NHS Trust, London, who initiated ART between 2001 and 2015, and achieved and maintained HIV-1 viral suppression (viral load <1,000 copies/ml). The association of age group at ART initiation with CD4 +  : CD8 + ratio at 5 and 10 years was assessed.

Causes of hospitalisation among a cohort of people with HIV from a London centre followed from 2011 to 2018.

Background: We describe the spectrum of ICD-10 classified causes for hospitalisations occurring between 2011 and 2018 in a cohort of people living with HIV (PLHIV).

Methods: This sub-study includes 798 PLHIV participating in the Antiretroviral, Sexual Transmission Risk and Attitudes (ASTRA) questionnaire study who were recruited from a large London centre. A medical record review identified the occurrence and causes of hospitalisation from the date of questionnaire completion (February-December 2011) until 1 June 2018.

Prospective association of social circumstance, socioeconomic, lifestyle and mental health factors with subsequent hospitalisation over 6-7 year follow up in people living with HIV.

Background: Predictors of hospitalisation in people with HIV (PLHIV) in the contemporary treatment era are not well understood.

Methods: This ASTRA sub-study used clinic data linkage and record review to determine occurrence of hospitalisations among 798 PLHIV from baseline questionnaire (February to December 2011) until 1 June 2018. Associations of baseline social circumstance, socioeconomic, lifestyle, mental health, demographic and clinical factors with repeated all-cause hospitalisation from longitudinal data were investigated using Prentice-Williams-Peterson models.