Leah Avery

Prof. Leah Avery

orcid

Research Focus & Metrics

Academic Career Length

18Years (2009-Present)

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

Representative Publications

View All Publications
21 March 2016 in Diabetes Care
Verified
Journal Article
Open access
PDF file
SSSarah Steven
Sarah Steven
KHKieren G. Hollingsworth
Kieren G. Hollingsworth
AAAhmad Al-Mrabeh
Ahmad Al-Mrabeh
LALeah Avery
Leah Avery
BABenjamin Aribisala
Benjamin Aribisala
RTRoy Taylor
Roy Taylor
OBJECTIVE: Type 2 diabetes mellitus (T2DM) is generally regarded as an irreversible chronic condition. Because a very low-calorie diet (VLCD) can bring about acute return to normal glucose control in some people with T2DM, this study tested the potential durability of this normalization. The underlying mechanisms were defined. RESEARCH DESIGN AND METHODS: People with a T2DM duration of 0.5–23 years (n = 30) followed a VLCD for 8 weeks. All oral agents or insulins were stopped at baseline. Following a stepped return to isocaloric diet, a structured, individualized program of weight maintenance was provided. Glucose control, insulin sensitivity, insulin secretion, and hepatic and pancreas fat content were quantified at baseline, after return to isocaloric diet, and after 6 months to permit the primary comparison of change between post–weight loss and 6 months in responders. Responders were defined as achieving fasting blood glucose <7 mmol/L after return to isocaloric diet. RESULTS: Weight fell (98.0 ± 2.6 to 83.8 ± 2.4 kg) and remained stable over 6 months (84.7 ± 2.5 kg). Twelve of 30 participants achieved fasting plasma glucose <7 mmol/L after return to isocaloric diet (responders), and 13 of 30 after 6 months. Responders had a shorter duration of diabetes and a higher initial fasting plasma insulin level. HbA1c fell from 7.1 ± 0.3 to 5.8 ± 0.2% (55 ± 4 to 40 ± 2 mmol/mol) in responders (P < 0.001) and from 8.4 ± 0.3 to 8.0 ± 0.5% (68 ± 3 to 64 ± 5 mmol/mol) in nonresponders, remaining constant at 6 months (5.9 ± 0.2 and 7.8 ± 0.3% [41 ± 2 and 62 ± 3 mmol/mol], respectively). The responders were characterized by return of first-phase insulin response. CONCLUSIONS: A robust and sustainable weight loss program achieved continuing remission of diabetes for at least 6 months in the 40% who responded to a VLCD by achieving fasting plasma glucose of <7 mmol/L. T2DM is a potentially reversible condition.

14 November 2012 in Diabetes Care
Verified
Journal Article
Open access
PDF file
LALeah Avery
Leah Avery
DFDarren Flynn
Darren Flynn
AWAnna van Wersch
Anna van Wersch
FSFalko F. Sniehotta
Falko F. Sniehotta
MTMichael I. Trenell
Michael I. Trenell
OBJECTIVE Behavioral interventions targeting “free-living” physical activity (PA) and exercise that produce long-term glycemic control in adults with type 2 diabetes are warranted. However, little is known about how clinical teams should support adults with type 2 diabetes to achieve and sustain a physically active lifestyle. RESEARCH DESIGN AND METHODS We conducted a systematic review of randomized controlled trials (RCTs) (published up to January 2012) to establish the effect of behavioral interventions (compared with usual care) on free-living PA/exercise, HbA1c, and BMI in adults with type 2 diabetes. Study characteristics, methodological quality, practical strategies for increasing PA/exercise (taxonomy of behavior change techniques), and treatment fidelity strategies were captured using a data extraction form. RESULTS Seventeen RCTs fulfilled the review criteria. Behavioural interventions showed statistically significant increases in objective (standardized mean difference [SMD] 0.45, 95% CI 0.21–0.68) and self-reported PA/exercise (SMD 0.79, 95% CI 0.59–0.98) including clinically significant improvements in HbA1c (weighted mean difference [WMD] –0.32%, 95% CI –0.44% to –0.21%) and BMI (WMD –1.05 kg/m2, 95% CI –1.31 to –0.80). Few studies provided details of treatment fidelity strategies to monitor/improve provider training. Intervention features (e.g., specific behavior change techniques, interventions underpinned by behavior change theories/models, and use of ≥10 behaviour change techniques) moderated effectiveness of behavioral interventions. CONCLUSIONS Behavioral interventions increased free-living PA/exercise and produced clinically significant improvements in long-term glucose control. Future studies should consider use of theory and multiple behavior change techniques associated with clinically significant improvements in HbA1c, including structured training for care providers on the delivery of behavioural interventions.

12 August 2017 in Autism
Verified
Journal Article
Closed access
PDF file
MAMichael Ayres
Michael Ayres
JPJeremy R Parr
Jeremy R Parr
JRJacqui Rodgers
Jacqui Rodgers
DMDavid Mason
David Mason
LALeah Avery
Leah Avery
DFDarren Flynn
Darren Flynn
Autism spectrum disorder is associated with co-existing conditions that may adversely affect an individual’s quality of life. No systematic review of quality of life of adults on the autism spectrum has been conducted. Our objectives were as follows: (1) review the evidence about quality of life for adults on the autism spectrum; (2) critically appraise current practice in assessing quality of life of adults on the autism spectrum. We searched bibliographic databases and other literature to identify studies using a direct measure of quality of life of adults on the autism spectrum. Hand searching of reference lists, citation searching and personal communication with field experts were also undertaken. In total, 827 studies were identified; 14 were included. Only one quality of life measure designed for use with the general autism spectrum population was identified. Quality of life of adults on the autism spectrum is lower than that of typically developing adults, when measured with tools designed for the general population. There are no comprehensive autism spectrum disorder–specific quality of life measurement tools validated for use with representative samples of adults on the autism spectrum. There is a pressing need to develop robust measures of quality of life of autistic adults.

28 October 2009 in Obesity Reviews
Verified
Journal Article
Open access
PDF file
Tamara BrownTamara Brown
Tamara Brown
AAA. Avenell
A. Avenell
LEL. D. Edmunds
L. D. Edmunds
HMH. Moore
H. Moore
VWV. Whittaker
V. Whittaker
FTfor the PROGRESS Team
for the PROGRESS Team
Summary: The aim of this article is to determine the effectiveness of long‐term lifestyle interventions for the prevention of weight gain and morbidity in adults. Prevention of weight gain is important in adults who are of normal weight, overweight and obese. A systematic review of controlled trials of lifestyle interventions in adults with a body mass index of less than 35 kg m−2 with at least 2 years of follow‐up was carried out. Eleven of 39 comparisons produced significant improvement in weight between groups at 2 years or longer with mean difference weight change ranging from −0.5 to −11.5 kg. Effective interventions included a 600 kcal/day deficit diet deficit/low‐fat diet (with and without meal replacements), low‐calorie diet, Weight Watchers diet, low‐fat non‐reducing diet, diet with behaviour therapy, diet with exercise, diet with exercise and behaviour therapy. Adding meal replacements to a low‐fat diet (with and without exercise and behaviour therapy) produced significant improvement in weight. Head‐to‐head interventions failed to show significant effect on weight with the exception of a Mediterranean diet with behaviour therapy compared with low‐fat diet. Diet with exercise and/or behaviour therapy demonstrated significant reduction in hypertension and improvement in risk of metabolic syndrome and diabetes compared with no treatment control. Lifestyle interventions demonstrated significant improvement in weight, reduction in hypertension and reduction in risk of type 2 diabetes and the metabolic syndrome.

25 July 2022 in BMJ Open
Verified
Journal Article
Open access
PDF file
MCMatthew Cooper
Matthew Cooper
LALeah Avery
Leah Avery
JSJason Scott
Jason Scott
KAKirsten Ashley
Kirsten Ashley
CJCara Jordan
Cara Jordan
DFDarren Flynn
Darren Flynn
Objective This study aims to establish the effectiveness and active ingredients of UK-based social prescribing interventions targeting mental health and well-being outcomes. Design Systematic review adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analysies guidelines and a published protocol. Data sources Nine databases were systematically searched up to March 2022. Eligibility criteria Social prescribing interventions in the UK involving adults aged ≥18 years, which reported on mental health outcomes. Data extraction and synthesis Two reviewers extracted data on study characteristics; outcomes; referral pathways; treatment fidelity strategies; person-centredness; intervention development processes and theory-linked behaviour change techniques (BCTs). Data were narratively synthesised. Results 52 074 records were retrieved by the search, 13 interventions reported across 17 studies were included in this review (N=5036 participants at post-intervention). Fifteen studies were uncontrolled before-and-after designs, one a randomised controlled trial and one a matched groups design. The most frequently reported referral pathway was the link worker model (n=12), followed by direct referrals from community services (n=3). Participants were predominantly working age adults, and were referred for anxiety, depression, social isolation and loneliness. 16 out of 17 studies reported statistically significant improvements in outcomes (mental health, mental well-being, general health, or quality of life). Strategies to enhance treatment fidelity were suboptimal across studies. Only two studies used a specific theoretical framework. A few studies reported engaging service users in codesign (n=2) or usability and/or feasibility testing (n=4). Overall, 22 BCTs were coded across 13 interventions. The most frequently coded BCTs were social support-unspecified (n=11), credible source (n=7) and social support-practical (n=6). Conclusions Robust conclusions on the effectiveness of social prescribing for mental health-related outcomes cannot be made. Future research would benefit from comprehensive intervention developmental processes, with reference to appropriate theory, alongside long-term follow-up outcome assessment, using treatment fidelity strategies and a focus on principle of person-centred care. PROSPERO registration number CRD42020167887.

12 May 2018 in Diabetologia
Verified
Journal Article
Open access
PDF file
DHDavid Houghton
David Houghton
THTimothy Hardy
Timothy Hardy
CSChristopher Stewart
Christopher Stewart
LELinda Errington
Linda Errington
CDChristopher P. Day
Christopher P. Day
LALeah Avery
Leah Avery
Aims/hypothesis Despite improved understanding of the pathophysiology of type 2 diabetes mellitus, explanations for individual variability in disease progression and response to treatment are incomplete. The gut microbiota has been linked to the pathophysiology of type 2 diabetes mellitus and may account for this variability. We conducted a systematic review to assess the effectiveness of dietary and physical activity/exercise interventions in modulating the gut microbiota and improving glucose control in adults with type 2 diabetes mellitus. Methods A systematic search was conducted to identify studies reporting on the effect of dietary and physical activity/exercise interventions on the gut microbiota and glucose control in individuals with a confirmed diagnosis of type 2 diabetes mellitus. Study characteristics, methodological quality and details relating to interventions were captured using a data-extraction form. Meta-analyses were conducted where sufficient data were available, and other results were reported narratively. Results Eight studies met the eligibility criteria of the systematic review. No studies were found that reported on the effects of physical activity/exercise on the gut microbiota and glucose control. However, studies reporting on dietary interventions showed that such interventions were associated with modifications to the composition and diversity of the gut microbiota. There was a statistically significant improvement in HbA1c (standardised mean difference [SMD] −2.31 mmol/mol [95% CI −2.76, −1.85] [0.21%; 95% CI −0.26, −0.16]; I2 = 0%, p < 0.01), but not in fasting blood glucose (SMD −0.25 mmol/l [95% CI −0.85, 0.35], I2 = 87%, p > 0.05), fasting insulin (SMD −1.82 pmol/l [95% CI −7.23, 3.60], I2 = 54%, p > 0.05) or HOMA-IR (SMD −0.15 [95% CI −0.63, 0.32], I2 = 69%, p > 0.05) when comparing dietary interventions with comparator groups. There were no significant changes in the relative abundance of bacteria in the genera Bifidobacterium (SMD 1.29% [95% CI −4.45, 7.03], I2 = 33%, p > 0.05), Roseburia (SMD −0.85% [95% CI −2.91, 1.21], I2 = 79%, p > 0.05) or Lactobacillus (SMD 0.04% [95% CI −0.01, 0.09], I2 = 0%, p > 0.05) when comparing dietary interventions with comparator groups. There were, however, other significant changes in the gut microbiota, including changes at various taxonomic levels, including phylum, family, genus and species, Firmicutes:Bacteroidetes ratios and changes in diversity matrices (α and β). Dietary intervention had minimal or no effect on inflammation, short-chain fatty acids or anthropometrics. Conclusions/interpretation Dietary intervention was found to modulate the gut microbiota and improve glucose control in individuals with type 2 diabetes. Although the results of the included studies are encouraging, this review highlights the need for further well-conducted interventional studies to inform the clinical use of dietary interventions targeting the gut microbiota.