Andrew M. Tonkin

Prof. Andrew M. Tonkin


Research Focus & Metrics

Academic Career Length

34Years (1993-Present)

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

Representative Publications

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13 December 2021 in BMC Geriatrics
Verified
Journal Article
Open access
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RFRosanne Freak-Poli
Rosanne Freak-Poli
JRJoanne Ryan
Joanne Ryan
JNJohannes Tobias Neumann
Johannes Tobias Neumann
ATAndrew M. Tonkin
Andrew M. Tonkin
CRChristopher M. Reid
Christopher M. Reid
Alice OwenAlice Owen
Alice Owen
Background: Poor social health is associated with increased risk of cardiovascular disease (CVD). Recent research suggests that different social health domains should be considered separately as the implications for health and possible interventions may differ. Aim: To assess social isolation, low social support and loneliness as predictors of CVD. Methods: Secondary analysis of 11,486 community-dwelling, Australians, aged 70 years and over, free of CVD, dementia, or significant physical disability, from the ASPirin in Reducing Events in the Elderly (ASPREE) trial. Social isolation, social support (Revised Lubben Social Network Scale), and loneliness were assessed as predictors of CVD using Cox proportional-hazard regression. CVD events included fatal CVD, heart failure hospitalization, myocardial infarction and stroke. Analyses were adjusted for established CVD risk factors. Results: Individuals with poor social health were 42 % more likely to develop CVD (p = 0.01) and twice as likely to die from CVD (p = 0.02) over a median 4.5 years follow-up. Interaction effects indicated that poorer social health more strongly predicted CVD in smokers (HR 4.83, p = 0.001, p-interaction = 0.01), major city dwellers (HR 1.94, p < 0.001, p-interaction=0.03), and younger older adults (70-75 years; HR 2.12, p < 0.001, p-interaction = 0.01). Social isolation (HR 1.66, p = 0.04) and low social support (HR 2.05, p = 0.002), but not loneliness (HR 1.4, p = 0.1), predicted incident CVD. All measures of poor social health predicted ischemic stroke (HR 1.73 to 3.16). Conclusions: Among healthy older adults, social isolation and low social support may be more important than loneliness as cardiovascular risk factors. Social health domains should be considered in future CVD risk prediction models.

28 January 2025 in Circulation
Verified
Journal Article
Open access
HBHarpreet S. Bhatia
Harpreet S. Bhatia
SWSimon Wandel
Simon Wandel
PWPeter Willeit
Peter Willeit
ALAnastasia Lesogor
Anastasia Lesogor
KBKeith Bailey
Keith Bailey
STSotirios Tsimikas
Sotirios Tsimikas
BACKGROUND: Low-density lipoprotein cholesterol (LDL-C) and lipoprotein(a) (Lp[a]) levels are independently associated with atherosclerotic cardiovascular disease (ASCVD). However, the relationship between Lp(a) level, LDL-C level, and ASCVD risk at different thresholds is not well defined. METHODS: A participant-level meta-analysis of 27 658 participants enrolled in 6 placebo-controlled statin trials was performed to assess the association of LDL-C and Lp(a) levels with risk of fatal or nonfatal coronary heart disease events, stroke, or any coronary or carotid revascularization (ASCVD). The multivariable-adjusted association between baseline Lp(a) level and ASCVD risk was modeled continuously using generalized additive models, and the association between baseline LDL-C level and ASCVD risk by baseline Lp(a) level by Cox proportional hazards models with random effects. The joint association between Lp(a) level and statin-achieved LDL-C level with ASCVD risk was evaluated using Cox proportional hazards models. RESULTS: Compared with an Lp(a) level of 5 mg/dL, increasing levels of Lp(a) were log-linearly associated with ASCVD risk in statin- and placebo-treated patients. Among statin-treated individuals, those with Lp(a) level >50 mg/dL (≈125 nmol/L) had increased risk across all quartiles of achieved LDL-C level and absolute change in LDL-C level. Even among those with the lowest quartile of achieved LDL-C level (3.1–77.0 mg/dL), those with Lp(a) level >50 mg/dL had greater ASCVD risk (hazard ratio, 1.38 [95% CI, 1.06–1.79]) than those with Lp(a) level ≤50 mg/dL. The greatest risk was observed with both Lp(a) level >50 mg/dL and LDL-C level in the fourth quartile (hazard ratio, 1.90 [95% CI, 1.46–2.48]). CONCLUSIONS: These findings demonstrate the independent and additive nature of Lp(a) and LDL-C levels for ASCVD risk, and that LDL-C lowering does not fully offset Lp(a)-mediated risk.

8 November 2023 in Nature Reviews Cardiology
Verified
Journal Article
Closed access
PDF file
HBHarpreet S. Bhatia
Harpreet S. Bhatia
RBRichard C. Becker
Richard C. Becker
GLGregor Leibundgut
Gregor Leibundgut
MPMitul Patel
Mitul Patel
PLPaul Lacaze
Paul Lacaze
STSotirios Tsimikas
Sotirios Tsimikas

28 November 2023 in Neurology
Verified
Journal Article
Closed access
PDF file
ZZZhen Zhou
Zhen Zhou
JRJoanne Ryan
Joanne Ryan
ATAndrew M. Tonkin
Andrew M. Tonkin
SZSophia Zoungas
Sophia Zoungas
PLPaul Lacaze
Paul Lacaze
MNMark Nelson
Mark Nelson
Background and Objectives: It has been suggested that higher triglyceride levels were associated with a lower risk of Alzheimer9s disease. This study aimed to examine the association of triglycerides with dementia and cognition change in community-dwelling older adults. Methods: This prospective longitudinal study used data from the ASPREE randomized trial of adults aged ≥65 years without dementia or previous cardiovascular events at enrolment. The main outcome was incident dementia. Other outcomes included changes in composite cognition and domain-specific cognition (global cognition, memory, language and executive function, and psychomotor speed). The association between baseline triglycerides and dementia risk was estimated using Cox proportional-hazard models adjusting for relevant risk factors. Linear mixed models were used to investigate cognitive change. The analysis was repeated in a sub-cohort of participants with available APOE-ε4 genetic data with additional adjustment for APOE-ε4 carrier status, and an external cohort (UK Biobank) with similar selection criteria applied. Results: The study included 18,294 ASPREE participants and 68,200 UK Biobank participants (mean age: 75.1 & 66.9 years; female: 56.3% & 52.7%; median [IQR] triglyceride:106 [80-142]mg/dl & 139 [101-193]mg/dl), with dementia recorded in 823 and 2,778 individuals over a median follow-up of 6.4 and 12.5 years, respectively. Higher triglyceride levels were associated with lower dementia risk in the entire ASPREE cohort (HR with doubling of TG: 0.82, 95% CI 0.72-0.94). Findings were similar in the sub-cohort of participants with APOE-ε4 genetic data (n=13,976), and in the UK Biobank cohort (HR was 0.82 and 0.83, respectively, all p≤0.01). Higher triglycerides were also associated with slower decline in global, composite cognition, and memory over time (p≤0.05). Discussion: Older adults with higher triglyceride levels within the normal to high-normal range had a lower dementia risk and slower cognitive decline over time compared to individuals with lower triglyceride levels. Higher triglyceride levels may be reflective of better overall health and/or lifestyle behaviors that would protect against dementia development. Future studies are warranted to investigate whether specific components within the total circulating pool of plasma triglycerides may promote better cognitive function, with the hope of informing the development of new preventive strategies.

1 March 2022 in Journal of the American Heart Association
Verified
Journal Article
Open access
PDF file
MWMalcolm West
Malcolm West
AKAdrienne Kirby
Adrienne Kirby
RSRalph A. Stewart
Ralph A. Stewart
SBStefan Blankenberg
Stefan Blankenberg
DSDavid Sullivan
David Sullivan
ATAndrew M. Tonkin
Andrew M. Tonkin
Background: Elevated plasma cystatin C levels reflect reduced renal function and increased cardiovascular risk. Less is known about whether the increased risk persists long‐term or is independent of renal function and other important biomarkers. Methods and Results: Cystatin C and other biomarkers were measured at baseline (in 7863 patients) and 1 year later (in 6106 patients) in participants in the LIPID (Long‐Term Intervention with Pravastatin in Ischemic Disease) study, who had a previous acute coronary syndrome. Outcomes were ascertained during the study (median follow‐up, 6 years) and long‐term (median follow‐up, 16 years). Glomerular filtration rate (GFR) was estimated using Chronic Kidney Disease Epidemiology Collaboration equations (first GFR‐creatinine, then GFR‐creatinine‐cystatin C). Over 6 years, in fully adjusted multivariable time‐to‐event models, with respect to the primary end point of coronary heart disease mortality or nonfatal myocardial infarction, for comparison of Quartile 4 versus 1 of baseline cystatin C, the hazard ratio was 1.37 (95% CI, 1.07–1.74; P =0.01), and for major cardiovascular events was 1.47 (95% CI, 1.19–1.82; P <0.001). Over 16 years, the association of baseline cystatin C with coronary heart disease, cardiovascular, and all‐cause mortality persisted (each P <0.001) and remained significant after adjustment for estimated GFR‐creatinine‐cystatin C. Cystatin C also predicted the development of chronic kidney disease for 6 years (odds ratio, 6.61; 95% CI, 4.28–10.20) independently of estimated GFR‐creatinine and other risk factors. However, this association was no longer significant after adjustment for estimated GFR‐creatinine‐cystatin C. Conclusions: Cystatin C independently predicted major cardiovascular events, development of chronic kidney disease, and cardiovascular and all‐cause mortality. Prediction of long‐term mortality was independent of improved estimation of GFR. Registration: URL: https://anzctr.org.au ; Unique identifier: ACTRN12616000535471.

14 September 2013 in International Journal of Vascular Medicine
Verified
Journal Article
Open access
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SHSultana Monira Hussain
Sultana Monira Hussain
BOBrian Oldenburg
Brian Oldenburg
YWYuanyuan Wang
Yuanyuan Wang
SZSophia Zoungas
Sophia Zoungas
ATAndrew M. Tonkin
Andrew M. Tonkin
Although South Asian populations have high cardiovascular disease (CVD) burden in the world, their patterns of individual CVD risk factors have not been fully studied. None of the available algorithms/scores to assess CVD risk have originated from these populations. To explore the relevance of CVD risk scores for these populations, literature search and qualitative synthesis of available evidence were performed. South Asians usually have higher levels of both “classical” and nontraditional CVD risk factors and experience these at a younger age. There are marked variations in risk profiles between South Asian populations. More than 100 risk algorithms are currently available, with varying risk factors. However, no available algorithm has included all important risk factors that underlie CVD in these populations. The future challenge is either to appropriately calibrate current risk algorithms or ideally to develop new risk algorithms that include variables that provide an accurate estimate of CVD risk.