Imperial College London

Dr Jonathan Underwood

Faculty of MedicineDepartment of Infectious Disease

Honorary Clinical Research Fellow



+44 (0)20 3312 1466jonathan.underwood Website CV




Winston Churchill WingSt Mary's Campus






BibTex format

author = {De, Francesco D and Underwood, J and Post, FA and Vera, JH and Williams, I and Boffito, M and Sachikonye, M and Anderson, J and Mallon, PWG and Winston, A and Sabin, CA},
doi = {10.1186/s12879-016-1970-8},
journal = {BMC Infectious Diseases},
title = {Defining cognitive impairment in people-living-with-HIV: the POPPY study},
url = {},
volume = {16},
year = {2016}

RIS format (EndNote, RefMan)

AB - BackgroundThe reported prevalence of cognitive impairment (CI) varies widely in cohorts of people living with HIV (PLWH); this may partly be due to the use of different diagnostic criteria. Agreement between diagnostic criteria of CI, the optimal definition to use, and associations with patient-reported cognitive symptoms have not been fully investigated.MethodsTwo hundred ninety PLWH aged >50 years and 97 matched negative controls completed a detailed assessment of cognitive function and three questions regarding cognitive symptoms. Age- and education-adjusted test scores (T-scores) determined if subjects met the following definitions of CI: Frascati, global deficit score (GDS) and the multivariate normative comparison (MNC) method.ResultsPLWH were more likely than controls to meet each definition of CI (ORs were 2.17, 3.12 and 3.64 for Frascati, GDS and MNC, respectively). Agreement of MNC with Frascati and GDS was moderate (Cohen’s k = 0.42 and 0.48, respectively), whereas that between Frascati and GDS was good (k = 0.74). A significant association was found between all the three criteria and reporting of memory loss but not with attention and reasoning problems. The 41 (14 %) PLWH meeting all the three criteria had the lowest median global T-score (36.9) and highest rate of symptom reporting (42 %).ConclusionsDifferent CI criteria show fair diagnostic agreement, likely reflecting their ability to exclude CI in the same group of individuals. Given the lower overall cognitive performance and higher rates of symptom reporting in those meeting all three criteria of CI, further work assessing this as a definition of CI in PLWH is justified.
AU - De,Francesco D
AU - Underwood,J
AU - Post,FA
AU - Vera,JH
AU - Williams,I
AU - Boffito,M
AU - Sachikonye,M
AU - Anderson,J
AU - Mallon,PWG
AU - Winston,A
AU - Sabin,CA
DO - 10.1186/s12879-016-1970-8
PY - 2016///
SN - 1471-2334
TI - Defining cognitive impairment in people-living-with-HIV: the POPPY study
T2 - BMC Infectious Diseases
UR -
UR -
UR -
VL - 16
ER -