David  Chang

Dr. David Chang


Research Focus & Metrics

Academic Career Length

20Years (2007-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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13 April 2022 in Journal of the International AIDS Society
Verified
Journal Article
Open access
AEAllahna L. Esber
Allahna L. Esber
DDavid Chang
David Chang
MIMichael Iroezindu
Michael Iroezindu
EBEmmanuel Bahemana
Emmanuel Bahemana
HKHannah Kibuuka
Hannah Kibuuka
TGthe AFRICOS Study Group
the AFRICOS Study Group
Introduction: Dolutegravir (DTG) has become a preferred component of first‐line antiretroviral therapy (ART) in many settings but may be associated with excess weight gain. We evaluated changes in weight and body mass index (BMI) after switch to single‐tablet tenofovir/lamivudine/dolutegravir (TLD) by people living with HIV (PLWH) in four African countries.Methods: The African Cohort Study (AFRICOS) prospectively follows adults with and without HIV in Kenya, Uganda, Tanzania and Nigeria. Demographics, ART regimen, weight, BMI and waist‐to‐hip ratio were collected every 6 months. Multivariable Cox proportional hazards modelling was used to estimate hazard ratios and 95% confidence intervals (CIs) for factors associated with developing a BMI ≥25 kg/m2. Linear mixed effects models with random effects were used to examine the average change in BMI, weight and waist‐to‐hip ratio.Results: From 23 January 2013 to 1 December 2020, 2950 PLWH were enrolled in AFRICOS and 1474 transitioned to TLD. In adjusted models, PLWH on TLD had 1.77 times the hazard of developing a high BMI (95% CI: 1.22–2.55) compared to PLWH on non‐TLD ART. Examining change in weight among all PLWH on ART, participants on TLD gained an average of 0.68 kg (95% CI: 0.32–1.04) more than PLWH on other regimens after adjusting for duration on ART, sex, age, study site and CD4 nadir. Among participants who switched to TLD, the average change in weight prior to TLD switch was 0.35 kg/year (95% CI: 0.25–0.46) and average change in weight was 1.46 kg/year (95% CI: 1.18–1.75) in the year following transition to TLD after adjustment for confounders.Conclusions: Elevated BMI and weight gain among PLWH on TLD are concerning safety signals. Implications for the development of metabolic comorbidities should be monitored, particularly if annual weight gain persists during continued follow‐up after transitioning to TLD.

17 March 2016 in Pharmaceuticals
Verified
Journal Article
Open access
PDF file
DDavid Chang
David Chang
RGRebecca A. Garcia
Rebecca A. Garcia
KAKevin S. Akers
Kevin S. Akers
KMKatrin Mende
Katrin Mende
CMClinton K. Murray
Clinton K. Murray
CSCarlos Sanchez
Carlos Sanchez
Acinetobacter baumannii is a challenging pathogen due to antimicrobial resistance and biofilm development. The role of iron in bacterial physiology has prompted the evaluation of iron-modulation as an antimicrobial strategy. The non-reducible iron analog gallium(III) nitrate, Ga(NO3)3, has been shown to inhibit A. baumannii planktonic growth; however, utilization of heme-iron by clinical isolates has been associated with development of tolerance. These observations prompted the evaluation of iron-heme sources on planktonic and biofilm growth, as well as antimicrobial activities of gallium meso- and protoporphyrin IX (Ga-MPIX and Ga-PPIX), metal heme derivatives against planktonic and biofilm bacteria of multidrug-resistant (MDR) clinical isolates of A. baumannii in vitro. Ga(NO3)3 was moderately effective at reducing planktonic bacteria (64 to 128 µM) with little activity against biofilms (≥512 µM). In contrast, Ga-MPIX and Ga-PPIX were highly active against planktonic bacteria (0.25 to 8 µM). Cytotoxic effects in human fibroblasts were observed following exposure to concentrations exceeding 128 µM of Ga-MPIX and Ga-PPIX. We observed that the gallium metal heme conjugates were more active against planktonic and biofilm bacteria, possibly due to utilization of heme-iron as demonstrated by the enhanced effects on bacterial growth and biofilm formation.

29 September 2022 in Journal of the International AIDS Society
Verified
Journal Article
Open access
DDavid Chang
David Chang
AEAllahna L. Esber
Allahna L. Esber
NDNicole F. Dear
Nicole F. Dear
MIMichael Iroezindu
Michael Iroezindu
EBEmmanuel Bahemana
Emmanuel Bahemana
TGthe AFRICOS Study Group
the AFRICOS Study Group
Introduction: Non‐communicable diseases (NCDs) are an important driver of morbidity among ageing people living with HIV (PLWH). We examined the composite role of age and HIV status on NCDs in people living with and without HIV.Methods: The African Cohort Study (AFRICOS) prospectively enrols participants aged ≥15 years with and without HIV at 12 sites in Kenya, Tanzania, Uganda and Nigeria. From 21 January 2013 to 1 September 2021, we assessed participants for renal insufficiency (estimated glomerular filtration rate 139 mmHg or diastolic BP >89 mmHg), obesity (body mass index >30 kg/m2), diabetes mellitus (DM) (fasting glucose ≥126 mg/dl or antidiabetic medication) and dysglycemia (fasting glucose ≥99 mg/dl or non‐fasting ≥199 mg/dl). Multivariable logistic regression with generalized estimating equations was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for factors associated with each NCD. The main exposure of interest was a composite of HIV status and age dichotomized around 50 years. All models were adjusted for study site and sex. The renal insufficiency model was additionally adjusted for elevated BP and dysglycemia.Results and discussion: Of 3761 participants with age data, 557 (14.8%) were age ≥50, 2188 (58.2%) were females and 3099 (82.4%) were PLWH. At enrolment, the prevalence of elevated BP, dysglycemia, renal insufficiency and obesity were n = 128 (26.9%), n = 75 (15.8%), n = 8 (1.7%) and n = 40 (8.4%), respectively, for PLWH ≥50. Compared to people without HIV age <50, PLWH age ≥50 had increased adjusted odds of having DM (OR: 2.78, 95% CI: 1.49–5.16), dysglycemia (OR: 1.98, 95% CI: 1.51–2.61) and renal insufficiency (OR: 6.20, 95% CI: 2.31–16.66). There were significant differences by study site, specifically, participants from Nigeria had the highest odds of elevated BP, dysglycemia and renal insufficiency as compared to Uganda.Conclusions: There was a high burden of NCDs in this African cohort with differences by geographic region. In order to promote healthy ageing with HIV, screening and treatment for common NCDs should be incorporated into routine HIV care with attention paid to geographic heterogeneity to better allocate resources.

16 March 2022 in The Lancet HIV
Verified
Journal Article
Closed access
DDavid Chang
David Chang
AEAllahna Esber
Allahna Esber
NDNicole Dear
Nicole Dear
MIMichael Iroezindu
Michael Iroezindu
EBEmmanuel Bahemana
Emmanuel Bahemana
CGCatherine Godfrey
Catherine Godfrey

1 September 2007 in Journal of the American College of Surgeons
Verified
Journal Article
Closed access
PDF file
SKShahrzad Kardooni
Shahrzad Kardooni
EHElliott R. Haut
Elliott R. Haut
CPCharles A. Pierce
Charles A. Pierce
DDavid Chang
David Chang
DEDavid T. Efron
David T. Efron
ECEdward E. Cornwell
Edward E. Cornwell