Dr Martin Whyte
I trained in medicine at King's College Hospital, qualifying in 1998. During my postgraduate medical training I undertook a PhD at Guy’s & St. Thomas’ Hospital (University of London) examining the metabolic effects of insulin in critical illness. I then competed my specialist training (CCT) in Diabetes & Endocrinology and General Medicine in 2010. Since 2012 I have combined my NHS Consultant work with that of a Clinical Senior Lecturer at The University of Surrey.
Areas of specialism
Type 2 diabetes mellitus;
University roles and responsibilities
- Faculty MD co-ordinator
- Department PGR co-ordinator
In the media
Use of stable isotope techniques to explore intermediary metabolism. In particular:
- Metabolic consequences of therapies for type 2 diabetes, obesity and bariatric surgery
- Nutritional and anti-catabolic strategies in perioperative medicine/critical illness
Use of big data:
- Cardiovascular sequealae of type 2 diabetes
- Long-term outcomes after acute hospitalisation
I am currently principal supervisor for four MD students
Module organiser for 'Obesity, Diabetes & Eating disorders' MSc in Nutritional Medicine
I lecture on diabetes & obesity to the following undergraduate courses:
Nutrition research methodology BMS3057
Physician Associate PASM002
Pathology of the endocrine system, nervous system and organs of special sense VMS2007
Int J Clinical Practice 2018 Nov;72(11):e13250. doi: 10.1111/ijcp.13250.
AIMS:Prolonged QT interval on electrocardiogram (ECG) increases the risk of ventricular arrhythmia. Patients admitted to acute medical units (AMU) may be at risk of QT prolongation from multiple, recognised risk factors. Few data exist regarding incidence or outcomes of QT prolongation in acute general medical admissions. The aims were to determine the incidence of Bazett's-corrected QT (QTc) prolongation upon admission to AMU; the relationship between QTc and inpatient mortality, length of stay and readmission; proportion with prolonged QTc subsequently administered QT interval-prolonging drugs.
METHODS:Retrospective, observational study of 1000 consecutive patients admitted to an AMU in a large urban hospital.
EXCLUSION CRITERIA:age <18 years, ventricular pacing, poor quality/absent ECG. QTc determined manually from ECG obtained within 4-hours of admission. QTc prolongation considered ≥470 milliseconds (males) and ≥480 milliseconds (females). In both genders, >500 milliseconds was considered severe. Study end-points, (a) incidence of QTc prolongation at admission; (b) inpatient mortality, length of stay and readmission rates; (c) proportion with QTc prolongation subsequently administered QT interval-prolonging drugs.
RESULTS:Of 1000 patients, 288 patients were excluded, therefore final sample was n = 712. Patient age (mean ± SD) was 63.1 ± 19.4 years; females 49%. QTc prolongation was present in n = 50 (7%) at admission; 1.7% had QTc interval >500 ms. Of the 50 patients admitted with prolonged QTc, 6 (12%) were subsequently administered QT interval-prolonging drugs. QTc prolongation was not associated with worse inpatient mortality or readmission rate. Length of stay was greater in those with prolonged QTc, 7.2 (IQR 2.4-13.2) days vs 3.3 (IQR 1.3-10.0; P = 0.004), however, in a regression model, presence of QTc did not independently affect length of stay.
CONCLUSIONS:QTc interval prolongation is frequent among patients admitted to AMU. QT interval-prolonging drugs are commonly prescribed to patients presenting with prolonged QTc but whether this affects clinical outcomes is uncertain
BackgroundBlack African (BA) populations are losing the cardio-protective lipid profile they historically exhibited, which may be linked with increasing fructose intakes. The metabolic effects of high fructose diets and how they relate to blood lipids are documented for Caucasians, but have not been described in BA individuals. Go to:
ObjectiveThe principle objective of this pilot study was to assess the independent impacts of high glucose and fructose feeding in men of BA ancestry compared to men of White European (WE) ancestry on circulating triglyceride (TG) concentrations. Go to:
MethodsHealthy males, aged 25–60 years, of BA (n = 9) and WE (n = 11) ethnicity were randomly assigned to 2 feeding days in a crossover design, providing mixed nutrient meals with 20 % total daily caloric requirements from either added glucose or fructose. Circulating TG, non-esterified fatty acids (NEFA), glucose, insulin and C-peptide were measured over two 24-h periods. Go to:
ResultsFasting TGs were lower in BAs than WEs on the fructose feeding day (p < 0.05). There was a trend for fasting TG concentrations 24 h following fructose feeding to increase in both BA (baseline median fasting: 0.80, IQR 0.6–1.1 vs 24-h median post-fructose: 1.09, 0.8–1.4 mmol/L; p = 0.06) and WE (baseline median fasting 1.10, IQR 0.9–1.5 vs 24-h median post-fructose: 1.16, IQR 0.96–1.73 mmol/L; p = 0.06). Analysis within ethnic group demonstrated that in TG iAUC was significantly higher in BA compared to WE on both glucose (35, IQR 11–56 vs −4, IQR −10–1 mmol/L/min; p = 0.004) and fructose (48, IQR 15–68 vs 13, IQR −7–38 mmol/L/min; p = 0.04). Greater suppression of postprandial NEFA was evident in WE than BA after glucose feeding (−73, IQR −81– −52 vs −26, IQR −48– −3 nmol/L/min; p = 0.001) but there was no ethnic difference following fructose feeding. Go to:
ConclusionsUnderstanding the metabolic effects of dietary acculturation and Westernisation that occurs in Black communities is important for developing prevention strategies for chronic disease development. These data show postprandial hypertriglyceridemia following acute feeding of high added fructose and glucose in BA men, compared to WE men, may contribute to metabolic changes observed during dietary acculturation and Westernisation
BackgroundThe aims of this study are the following: to describe the female population of reproductive age having bariatric surgery in the UK, to assess the age and ethnicity of women accessing surgery, and to assess the effect of bariatric surgery on factors that underlie fertility and pregnancy outcomes.
MethodsDemographic details, comorbidities, and operative type of women aged 18–45 years were extracted from the National Bariatric Surgery Registry (NBSR). A comparison was made with non-operative cases (aged 18–45 and BMI ≥40 kg/m2) from the Health Survey for England (HSE, 2007–2013). Analyses were performed using “R” software.
ResultsData were extracted on 15,222 women from NBSR and 1073 from HSE. Women aged 18–45 comprised 53 % of operations. Non-Caucasians were under-represented in NBSR compared to HSE (10 vs 16 % respectively, p < 0.0001). The NBSR group was older than the HSE group—median 38 (IQR 32–42) vs 36 (IQR 30–41) years (Wilcoxon test p < 0.0001). Almost one third of women in NBSR had menstrual dysfunction at baseline (33.0 %). BMI fell in the first year postoperatively from 48.2 ± 8.3 to 37.4 ± 7.5 kg/m2 (t test, p < 0.001). From NBSR, in the postoperative period, the prevalence of type 2 diabetes fell by 54 %, polycystic ovarian syndrome by 15 %, and any menstrual dysfunction by 12 %.
ConclusionsOver half of all bariatric procedures are carried out on women of reproductive age. More work is required to provide prompt and equal access across ethnic groups. At least one in three women suffers from menstrual dysfunction at baseline. Bariatric surgery improves factors that underlie fertility and pregnancy outcomes. A prospective study is required to verify these effects
AIMS/HYPOTHESIS:It is not known whether the beneficial effects of exercise training on insulin sensitivity are due to changes in hepatic and peripheral insulin sensitivity or whether the changes in insulin sensitivity can be explained by adaptive changes in fatty acid metabolism, changes in visceral fat or changes in liver and muscle triacylglycerol content. We investigated the effects of 6 weeks of supervised exercise in sedentary men on these variables.
SUBJECTS AND METHODS:We randomised 17 sedentary overweight male subjects (age 50 +/- 2.6 years, BMI 27.6 +/- 0.5 kg/m(2)) to a 6-week exercise programme (n = 10) or control group (n = 7). The insulin sensitivity of palmitic acid production rate (Ra), glycerol Ra, endogenous glucose Ra (EGP), glucose uptake and glucose metabolic clearance rate were measured at 0 and 6 weeks with a two-step hyperinsulinaemic-euglycaemic clamp [step 1, 0.3 (low dose); step 2, 1.5 (high dose) mU kg(-1) min(-1)]. In the exercise group subjects were studied >72 h after the last training session. Liver and skeletal muscle triacylglycerol content was measured by magnetic resonance spectroscopy and visceral adipose tissue by cross-sectional computer tomography scanning.
RESULTS:After 6 weeks, fasting glycerol, palmitic acid Ra (p = 0.003, p = 0.042) and NEFA concentration (p = 0.005) were decreased in the exercise group with no change in the control group. The effects of low-dose insulin on EGP and of high-dose insulin on glucose uptake and metabolic clearance rate were enhanced in the exercise group but not in the control group (p = 0.026; p = 0.007 and p = 0.04). There was no change in muscle triacylglycerol and liver fat in either group.
CONCLUSIONS/INTERPRETATION:Decreased availability of circulating NEFA may contribute to the observed improvement in the insulin sensitivity of EGP and glucose uptake following 6 weeks of moderate exercise
CONTEXT:Declines in GH and testosterone (Te) secretion may contribute to the detrimental aging changes of elderly men.
OBJECTIVE:To assess the effects of near-physiological GH with/without Te administration on lean body mass, total body fat, midthigh muscle cross-section area, muscle strength, aerobic capacity, condition-specific quality of life (Age-Related Hormone Deficiency-Dependent Quality of Life questionnaire), and generic health status (36-Item Short-Form Health Survey) of older men.
DESIGN, SETTINGS, AND PARTICIPANTS:A 6-month, randomized, double-blind, placebo-controlled trial was performed on 80 healthy, community-dwelling, older men (age, 65-80 yr).
INTERVENTIONS:Participants were randomized to receive 1) placebo GH or placebo Te, 2) recombinant human GH (rhGH) and placebo Te (GH), 3) Te and placebo rhGH (Te), or 4) rhGH and Te (GHTe). GH doses were titrated over 8 wk to produce IGF-I levels in the upper half of the age-specific reference range. A fixed dose of Te (5 mg) was given by transdermal patches.
RESULTS:Lean body mass increased with GHTe (P = 0.008) and GH (P = 0.004), compared with placebo. Total body fat decreased with GHTe only (P = 0.02). Midthigh muscle (P = 0.006) and aerobic capacity (P < 0.001) increased only after GHTe. Muscle strength changes were variable; one of six measures significantly increased with GHTe. Significant treatment group by time interactions indicated an improved Age-Related Hormone Deficiency-Dependent Quality of Life questionnaire score (P = 0.007) in the GH and GHTe groups. Bodily pain increased with GH alone, as determined by the Short-Form Health Survey (P = 0.003). There were no major adverse effects.
CONCLUSION:Coadministration of low dose GH with Te resulted in beneficial changes being observed more often than with either GH or Te alone.
Postgraduate Medical Journal Nov 2018 November 2018. doi: 10.1136/postgradmedj-2018-135983
Diabetic Medicine 2019 May;36(5):653-654
Clinical Medicine 2019; Jan;19(1):86-87.
BMJ 2019 365: l1719
Diabetes/Metabolism Research & Reviews. 2019 May 29:e3191. doi: 10.1002/dmrr.3191. [Epub ahead of print]
Br J Midwifery 2019; 27(7): 413-419
BMC Health Services Research 2019; 19:284
Journal Royal College Physicians Edinburgh 2019; 49(2): 172-173
Surgical Endoscopy 2019 Jul 18. doi: 10.1007/s00464-019-06958-w
Surgical Endoscopy 2019 Jul 16. doi: 10.1007/s00464-019-06961-1.
Obesity Reviews 2019 Aug 16. doi: 10.1111/obr.12927. [Epub ahead of print]
JRSM Cardiovascular Disease 2019 ePub ahead of print