Long-term testosterone therapy in type 2 diabetes is associated with reduced mortality without improvement in conventional cardiovascular risk factors.

OBJECTIVES: To further characterize the beneficial impact of testosterone replacement therapy (TRT) on the association between mortality and hypogonadism (HG) in men with type 2 diabetes (T2DM), by determining, firstly, if changes in cardiovascular disease (CVD) risk factors after TRT play a role, secondly, whether the reduction in mortality is lost when TRT is discontinued and, finally, the presence of subgroups where benefit may be greater. MATERIALS AND METHODS: We studied 857 men with T2DM, screened for the BLAST randomized controlled trial, over 3.8 years of follow-up. The men were stratified first by testosterone levels: group 1: total testosterone (TT) >12 nmol/L and free testosterone (FT) >0.25 nmol/L; Group 2: TT ≤12 nmol/L or FT ≤0.25 nmol/L. Group 2 was further stratified into those not on TRT (Group 2a) and those on TRT (Group 2b). Group 2b was further stratified by whether TRT was discontinued (Group 2b1) or not (Group 2b2). The principal outcome, mortality, was studied using Cox regression. RESULTS: We found that TRT was not associated with improvements in CVD risk factors. CVD risk factors (baseline and changes during follow-up) were not associated with mortality. Men in Group 1 and Group 2b were found to have lower mortality (reference: Group 2a), even with CVD risk factors included in the regression models. Mortality was lower in men in Group 2b1 (6.2%) and Group 2b2 (0%) compared with those in Group 2a (16.9%). The lower mortality associated with Group 1 and Group 2b was observed primarily in older (>64.6 years) and less overweight (≤93.8 kg) men. CONCLUSIONS: The benefits associated with normal testosterone levels and TRT (even after discontinuation) do not appear to be related to improvements in the CVD risk factors studied. In view of TRT having greater impact in men of lower weight, better outcomes may be achieved with concurrent TRT and weight reduction programmes.

A study in high-risk, maximally pretreated patients to determine the potential use of PCSK9 inhibitors at various thresholds of total and LDL cholesterol levels.

PURPOSE OF THE STUDY: Statins and ezetimibe reduce low-density lipoprotein cholesterol (LDL-c) and cardiovascular disease (CVD) risk. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors lower LDL-c by 50%-70% and might be useful in refractory patients. The National Institute for Health and Care Excellence (NICE) technology appraisal guidance (TAG) recommends use of these drugs in secondary prevention and familial hypercholesterolaemia (FH) at differing LDL-c thresholds. We have estimated the proportion of patients in whom this third-line drug might be useful. STUDY DESIGN: We used data from a lipid-lowering audit programme to study 72 with FH and/or CVD of 271 patients referred over 12 months who failed to achieve target total cholesterol (TC) and LDL-c levels. All 72 patients were treated with ezetimibe, and 69 cases also received statins. We used LDL-c thresholds 1.5-5.5 mmol/L to estimate how many of these refractory patients could benefit from PCSK9 inhibitors. RESULTS: In 72 patients, TC and LDL-c targets were not met by 64 and 53 patients, respectively. We judged using the NICE TAG that only one patient (1.4% ezetimibe requiring and 0.4% total referrals) required a PCSK9 inhibitor. CONCLUSIONS: We determined that the proportion of patients eligible for a PCSK9 inhibitor at various TC and LDL-c levels is modest. This may reflect the use of all available statins in UK lipid clinics often at non-daily frequency. We suggest that cost-effective use of PCSK9 inhibitors requires prescribing being restricted to clinicians working in specialised lipid clinics.

Testosterone Replacement Therapy: Effects on Blood Pressure in Hypogonadal Men.

PURPOSE: While testosterone therapy can improve the various pathologies associated with adult-onset testosterone deficiency (TD), Summary of Product Characteristics (SPC) of five testosterone preparations caution that treatment may be associated with hypertension. This paper evaluates the impact of testosterone undecanoate (TU) on blood pressure (BP) in men with adult-onset TD. MATERIALS AND METHODS: Of 737 men with adult-onset TD in an on-going, observational, prospective, cumulative registry, we studied changes in BP using non-parametric sign-rank tests at final assessment and fixed time points. We used multiple regression analysis to establish factors (baseline BP, age, change/baseline waist circumference [WC] and hematocrit [HCT] and follow-up) potentially associated with BP change in men on TU. RESULTS: TU was associated with significant reductions in systolic, diastolic BP and pulse pressure, regardless of antihypertensive therapy (at baseline or during follow-up), larger reductions were seen with concurrent antihypertensive therapy. In men never on antihypertensive agents, median changes (interquartile range [IQR]) in systolic BP, diastolic BP and pulse pressure were -12.5 (-19.0, -8.0), -8.0 (-14.0, -3.0), and -6.0 (-10.0, -1.0) mmHg, respectively at final assessment, with only baseline BP values inversely associated with these changes (HCT and WC were not significantly associated). In men not on TU, systolic BP, diastolic BP, and pulse pressure significantly increased. In the TU treated men only 1 of the 152 men (not on antihypertensive agents at baseline) were started on antihypertensives during follow-up. In contrast 33 of the 202 men on antihypertensives (at baseline or follow-up) had the antihypertensive agent discontinued by the end of the follow-up. CONCLUSIONS: TU was associated with lowering of BP during follow-up irrespective of antihypertensive therapy, with greater reductions in men with higher baseline BP. In the context of SPC warnings, our long-term data provide reassurance on the effect of TU on BP.

Testosterone replacement therapy: association with mortality in high-risk patient subgroups.

OBJECTIVES: We describe studies determining the association between testosterone therapy (TTh) and mortality. MATERIALS & METHODS: We used a registry database of 737 men with adult-onset testosterone deficiency defined as presenting with low serum total testosterone (TT) levels ≤12.1 nmol/L and associated symptoms over a near 10-year follow-up. We compared associations between testosterone undecanoate (TU), cardio-metabolic risk factors and mortality using non-parametric statistics followed by separate Cox regression models to determine if any association between TU and morality was independent of age and cardio-metabolic risk factors. Finally, the association between TU and mortality was studied in men stratified by cardio-metabolic risk. RESULTS: During a median follow-up interquartile range (IQR) of 114 (84-132) months, 94 of the 737 men died. TU (ref: non-treatment) was associated with mortality; hazard ratio = 0.23, 95% confidence intervals = 0.14-0.40. Cox's regression models showed the above association to be independent of baseline age, waist circumference, hemoglobin A1c, lipids, blood pressure, smoking, and type 2 diabetes. These variables remained associated with mortality. We finally stratified the men by the high-risk baseline variables and established that the association between mortality and TU was only evident in men at higher risk. A possible explanation could lie with the "law of initial value," where greater improvements are evident following treatment in patients with worse baseline values. CONCLUSIONS: This study with long follow-up confirms that TTh is associated with lower mortality in men with adult-onset TD. This association was evident only in men with greater cardio-metabolic risk factors who demonstrated greater benefit.

The Multiple Sclerosis Severity Score: associations with MC1R single nucleotide polymorphisms and host response to ultraviolet radiation.

BACKGROUND: Multiple sclerosis outcome may be influenced by ultraviolet radiation and vitamin D synthesis, suggesting skin type and genes determining this phenotype are candidates for disability. However, though associations between melanocortin 1 receptor (MC1R) single nucleotide polymorphisms and disability are reported, some data are incompatible with their expected influence on skin type. OBJECTIVE: Determine which MC1R single nucleotide polymorphisms affect disability and establish if ultraviolet radiation modifies such associations. METHODS: We studied using linear regression in 525 cases, associations of the Multiple Sclerosis Severity Score (MSSS) with skin type, gender, ultraviolet radiation exposure and six MC1R single nucleotide polymorphisms (rs1805005, rs1805006, rs2228479, rs1805007, rs1805008, rs1805009). RESULTS: CG(294) with GG(294) genotypes (rs1805009) (coefficient = -1.44, 95% CI -2.30, -0.59, mean MSSS +/- SD = 4.33 +/- 2.87) and AC(84) (rs1805006) (coefficient = 1.62, 95% CI 0.17, 3.06, mean MSSS = 7.62 +/- 2.43) were associated with MSSS. Associations with Asp294His were found in those with skin types 1/2 and 3/4, and cases stratified by ultraviolet radiation exposure. However, they were seen only in cases with a history of childhood sunburn and not in those without sunburn. We found no significant associations between exposure parameters and MSSS. CONCLUSIONS: Multiple sclerosis outcome is influenced by interactions between host response to ultraviolet radiation and MC1R single nucleotide polymorphisms. The influence of the single nucleotide polymorphisms appears distinct from their association with skin type.

Testosterone replacement therapy: Pre-treatment sex hormone-binding globulin levels and age may identify clinical subgroups.

BACKGROUND: Testosterone replacement therapy (TRT) improves health in some but not all men with type 2 diabetes (T2DM) and adult-onset testosterone deficiency (TD). Such heterogeneity is compatible with the concept of patient subgroups that respond differently to therapy. OBJECTIVES: Use baseline SHBG and age to identify putative subgroups that demonstrate different responses in variables such as waist circumference and HbA1c following TRT. MATERIALS AND METHODS: A randomized double-blind trial approach was used to recruit and randomize men with T2DM and adult-onset TD into placebo and TRT-treated groups. Multiple regression was used to study differences between groups. RESULTS: Baseline SHBG and change in SHBG (∆SHBG) were inversely related in the TRT group. Both median values of SHBG and age mediated the effect of TRT on ∆SHBG depending on whether baseline values were ≤ or>median (28.1 nmol/L, 63 years, respectively). In men with both SHBG ≤ 28.1 nmol/L and age ≤ 63 years (subgroup 1), TRT was positively associated with ∆SHBG (c = 4.67, 95%CI 1.17-8.16, P = .010) while in those with SHBG > 28.1 nmol/L and age > 63.1 years (subgroup 4) the association was inverse (c = -7.07, 95%CI -11.64 to -2.49, P = .003). The association between TRT and change (∆) in waist circumference, HbA1c and International Index of Erectile Function (IIEF) score differed between subgroups; in subgroup 4 but not subgroup 1, the therapy was significantly associated with ∆waist circumference, ∆HbA1c and ∆IIEF. DISCUSSION: Though the mechanism remains unclear, our finding of different responses to TRT in terms of change in waist circumference, HbA1c and IIEF score supports the concept of subgroups in men with T2DM and adult-onset TD. CONCLUSION: Our approach may provide a basis for identifying men who will or will not derive benefit from TRT though a larger study is required.

Long-Term Testosterone Therapy in Type 2 Diabetes Is Associated with Decreasing Waist Circumference and Improving Erectile Function.

PURPOSE: To describe the 4-year metabolic follow-up results from the BLAST study. MATERIALS AND METHODS: Baseline hemoglobin A1c (HbA1c), weight, and waist circumference (WC) data were recorded in 185 men recruited for the BLAST randomised controlled trial (RCT) and erectile function (EF) scores were also available in an additional 48 men screened for the RCT. Intra/inter-group associations between these parameters and testosterone replacement therapy (TRT) were assessed at 1) end of the RCT (30 weeks), 2) open-label phase (82 weeks), and 3) final assessment via non-parametric statistics. RESULTS: Improvement in HbA1c and weight at the end of the RCT and open-label phase in men on TRT was not maintained long-term. The convergence in HbA1c could have been due to incentivised care with HbA1c targets. Interestingly those on TRT at final assessment required fewer anti-diabetic agents. The weight increase in routine care may have been due to changes in diabetes medication or an increase in lean muscle mass. WC continued to decrease in men on TRT indicating possible reduction in visceral fat. Improvement in EF scores continued with long-term TRT, this was abolished when TRT was discontinued. CONCLUSIONS: This study hints at benefits in glycaemic control, weight and WC, and long-term RCTs studying mechanisms of benefit and clinical outcomes are necessary. Our results also show that EF scores continued to improve with long-term TRT, even beyond the 6 months that we previously reported in the BLAST RCT.

Patients with both basal and squamous cell carcinomas are at a lower risk of further basal cell carcinomas than patients with only a basal cell carcinoma.

BACKGROUND: The rate of development of further basal cell carcinoma (BCC) after first presentation is highly variable. The mechanisms that determine this phenotypic difference are unclear. OBJECTIVE: We assessed the risks of developing a subsequent BCC in patients who developed a BCC and a squamous cell carcinoma (SCC) and compared them with patients who developed a BCC only. METHODS: In all, 1040 patients who developed BCC only were compared with 140 patients who developed BCC and SCC to see whether the latter group included a high proportion of risk phenotypes (eg, male sex and fair skin). We then compared the number of BCCs developing per year in the two groups (174 BCC only and 71 BCC/SCC) during a 5-year period after initial BCC presentation. RESULTS: The BCC/SCC group demonstrated a significantly lower BCC/year rate than BCC only group. The rate of development of further BCC during 5-year follow-up was lower in the BCC/SCC group because a smaller number of patients developed subsequent BCC and not because the same proportion of patients developed lesions but in smaller numbers. After 5 years of follow-up, 51.1% of BCC and 74.6% of BCC/SCC cases were free from a subsequent BCC. Logistic regression analysis corrected for age at initial presentation confirmed that patients with BCC/SCC were less likely to develop a further BCC during the 5 years after initial presentation (P = .001, odds ratio = 0.31, 95% confidence interval 0.15-0.63). LIMITATIONS: Because of the large patient group and long study follow-up from the date of the index BCC or SCC, not all data were obtained. Where this is the case, the number of patients for whom the information is available is provided. CONCLUSIONS: Patients who develop a BCC are similar to patients who develop both a BCC and SCC, confirming the overlap of causative factors. Patients who develop both a BCC and SCC are less likely to develop BCCs compared with patients who develop BCC only.

Sex Hormone Binding Globulin: A Review of its Interactions With Testosterone and Age, and its Impact on Mortality in Men With Type 2 Diabetes.

INTRODUCTION: The age-related fall in male testosterone levels can have clinical consequences. The concentration of serum-free testosterone, the putative bioactive moiety, is mediated by carrier proteins, especially SHBG. AIM: The aim of this study was to consider the nature of hormone binding to carriers with new insights into determining calculated free testosterone levels and review how SHBG and testosterone influence age-related mortality. METHODS: Where possible, we focused on recent literature describing binding of testosterone to carrier proteins or, associations among age, SHBG, testosterone, and mortality. We then used logistic regression to study the impact of SHBG and total testosterone on age-related mortality in men with type 2 diabetes mellitus (T2DM). MAIN OUTCOME MEASURES: The association between mortality and age and SHBG and/or total testosterone was determined in a cohort of 364 men with T2DM leading to a graphical display of the impact of SHBG/testosterone levels on age-related mortality. RESULTS: Low total testosterone and high SHBG are independently associated with increased all-cause mortality. Our analyses support these findings showing that men with T2DM and a combination of total testosterone <12 nmol/L and SHBG >35nmol/L (odds ratio [OR]: 3.05; 95% CI: 1.43-6.53; P = .004) demonstrated an increased risk of mortality, independent of age (OR: 1.08; 95% CI: 1.06-1.11; P < .001). We graphically demonstrated that the risk combination altered the relationship between age and mortality. CONCLUSION: Until free testosterone is precisely, accurately, and conveniently measured, calculated values may provide useful even if somewhat inaccurate estimates. We also suggest that SHBG and testosterone assays are standardized to allow establishment of diagnostic and treatment thresholds. Although it is possible that the association in men with T2DM, among the combination of SHBG and total testosterone and age-related mortality is driven by free hormone levels, it is so far, unproven. Sudarshan Ramachandran, Geoffrey I. Hackett, Richard C. Strange, et al. Sex Hormone Binding Globulin: A Review of its Interactions With Testosterone and Age, and its Impact on Mortality in Men With Type 2 Diabetes. Sex Med Rev 2019;7:669-678.

Testosterone Therapy: An Assessment of the Clinical Consequences of Changes in Hematocrit and Blood Flow Characteristics.

INTRODUCTION: Clinical guidelines indicate that hematocrit should be monitored during testosterone replacement therapy (TTh), with action taken if a level of 0.54 is exceeded. AIM: To consider the extent of changes in hematocrit and putative effects on viscosity, blood flow, and mortality rates after TTh. METHODS: We focused on literature describing benefits and possible pitfalls of TTh, including increased hematocrit. We used data from the BLAST RCT to determine change in hematocrit after 30 weeks of TTh and describe a clinical case showing the need for monitoring. We consider the validity of the current hematocrit cutoff value at which TTh may be modified. Ways in which hematocrit alters blood flow in the micro- and macro-vasculature are also considered. MAIN OUTCOME MEASURES: The following measures were assessed: (i) change in hematocrit, (ii) corresponding actions taken in clinical practice, and (iii) possible blood flow changes following change in hematocrit. RESULTS: Analysis of data from the BLAST RCT showed a significant increase in mean hematocrit of 0.01, the increase greater in men with lower baseline values. Although 0 of 61 men given TTh breached the suggested cutoff of 0.54 after 30 weeks, a clinical case demonstrates the need to monitor hematocrit. An association between hematocrit and morbidity and mortality appears likely but not proven and may be evident only in patient subgroups. The consequences of an increased hematocrit may be mediated by alterations in blood viscosity, oxygen delivery, and flow. Their relative impact may vary in different vascular beds. CONCLUSIONS: TTh can effect an increased hematocrit via poorly understood mechanisms and may have harmful effects on blood flow that differ in patient subgroups. At present, there appears no scientific basis for using a hematocrit of 0.54 to modify TTh; other values may be more appropriate in particular patient groups. König CS, Balabani S, Hackett GI, et al. Testosterone Therapy: An Assessment of the Clinical Consequences of Changes in Hematocrit and Blood Flow Characteristics. Sex Med Rev 2019;7:650-660.

Meta-analysis and pooled analysis of GSTM1 and CYP1A1 polymorphisms and oral and pharyngeal cancers: a HuGE-GSEC review.

The association of GSTM1 and CYP1A1 polymorphisms and oral and pharyngeal cancers was assessed through a meta-analysis of published case-control studies and a pooled analysis of both published and unpublished case-control studies from the Genetic Susceptibility to Environmental Carcinogens database (http://www.upci.upmc.edu/research/ccps/ccontrol/index.html ). Thirty publications used in the meta-analysis included a total of 7783 subjects (3177 cases and 4606 controls); 21 datasets, 9397 subjects (3130 cases and 6267 controls) were included in the pooled analysis. The GSTM1 deletion was 2-fold more likely to occur in African American and African cases than controls (odds ratio: 1.7, 95% confidence interval: 0.9-3.3), although this was not observed among whites (odds ratio: 1.0, 95% confidence interval: 0.9-1.1). The meta-analysis and pooled analysis showed a significant association between oral and pharyngeal cancer and the CYP1A1 MspI homozygous variant (meta-ORm2/m2: 1.9, 95% confidence interval: 1.4-2.7; Pooled ORm2m2: 2.0, 95% confidence interval: 1.3-3.1; ORm1m2 or [infi]m2m2: 1.3, 95% confidence interval: 1.1-1.6). The association was present for the CYP1A1 (exon 7) polymorphism (ORVal/Val: 2.2, 95% confidence interval: 1.1-4.5) in ever smokers. A joint effect was observed for GSTM1 homozygous deletion and the CYP1A1 m1m2 variant on cancer risk. Our findings suggest that tobacco use and genetic factors play a significant role in oral and pharyngeal cancer.

Differential effects of glutathione S-transferase pi (GSTP1) haplotypes on cell proliferation and apoptosis.

Expression of the glutathione S-transferase, GSTP1, is associated with phase 1 detoxification of the products of oxidative stress. Recently, GSTP1 expression has been implicated in the regulation of cell proliferation and apoptosis through direct interaction with the c-Jun N-terminal kinase, (JNK). GSTP1 is polymorphic and allelic variants have been associated with disease susceptibility and clinical outcome. However, the influence of GSTP1 alleles on proliferation and apoptosis has not been studied previously. To investigate this, we have examined the effects of inducible expression of wild-type GSTP1*A and mutant GSTP1*C haplotypes on cell proliferation and apoptosis in NIH3T3 fibroblasts. Cells expressing GSTP1*A displayed increased doubling times and a delayed G1-S phase transition compared with cells expressing GSTP1*C. Both GSTP1*A and GSTP1*C haplotypes protected cells from undergoing apoptosis when exposed to oxidative stress. However, analysis of JNK status revealed that only GSTP1*C expression led to a reduction in JNK activity compared with GSTP1*A-expressing cells and non-induced cells. We further examined the effect of GSTP1 alleles on colony-forming efficiency (CFE) in soft agar following exposure to oxidative stress and found that GSTP1*A-expressing clones had increased CFE compared with non-induced and GSTP1*C-expressing clones. Our data suggest that GSTP1 alleles have differential effects on proliferation and apoptosis; GSTP1*A reduces cellular proliferation and protects against apoptosis through a JNK-independent mechanism. In contrast, GSTP1*C does not influence cellular proliferation but protects cells from apoptosis through JNK-mediated mechanisms.

Prostate cancer susceptibility is mediated by interactions between exposure to ultraviolet radiation and polymorphisms in the 5' haplotype block of the vitamin D receptor gene.

Vitamin D receptor (VDR) polymorphisms are prostate cancer risk candidates. We determined if SNPs in haplotype block sub-regions C2 (SNPs C2-1, G/C(3436), C2-2, A/G(3944)) or C1 (C1-1, C/T(20965), C1-2, C/T(30056)) are associated with risk in an ultraviolet radiation (UVR)-dependent manner. In men with very low exposure, SNPs in both sub-regions were associated with risk. Various haplotypes in haplotype block C including G(3436)-A(3944)-C(20965)-C(30056), (G or C)-A-C-C and G-A-(C or T)-C were significantly associated with increased risk (odds ratios between 1.95 and 2.37). These findings suggest various block C SNPs are associated with prostate cancer risk via a mechanism involving exposure to sunlight.

Vitamin D and oestrogen receptor polymorphisms in developmental dysplasia of the hip and primary protrusio acetabuli--a preliminary study.

We investigated the association of developmental dysplasia of the hip (DDH) and primary protrusion acetabuli (PPA) with Vitamin D receptor polymorphisms Taq I and Fok I and oestrogen receptor polymorphisms Pvu II and Xba I. 45 patients with DDH and 20 patients with PPA were included in the study. Healthy controls (n = 101) aged 18-60 years were recruited from the same geographical area. The control subjects had a normal acetabular morphology based on a recent pelvic radiograph performed for an unrelated cause. DNA was obtained from all the subjects from peripheral blood. Genotype frequencies were compared in the three groups. The relationship between the genotype and morphology of the hip joint, severity of the disease, age at onset of disease and gender were examined. The oestrogen receptor Xba I wild-type genotype (XX, compared with Xx and xx combined) was more common in the DDH group (55.8%) than controls (37.9%), though this just failed to achieve statistical significance (p = 0.053, odds ratio = 2.1, 95% CI = 0.9-4.6). In the DDH group, homozygosity for the mutant Taq I Vitamin D receptor t allele was associated with higher acetabular index (Mann-Whitney U-test, p = 0.03). Pvu II pp oestrogen receptor genotype was associated with low centre edge angle (p = 0.07). This study suggests a possible correlation between gene polymorphism in the oestrogen and vitamin D receptors and susceptibility to, and severity of DDH. The Taq I vitamin D receptor polymorphisms may be associated with abnormal acetabular morphology leading to DDH while the Xba I oestrogen receptor XX genotype may be associated with increased risk of developing DDH. No such correlations were found in the group with PPA.

Statin, testosterone and phosphodiesterase 5-inhibitor treatments and age related mortality in diabetes.

AIM: To determine how statins, testosterone (T) replacement therapy (TRT) and phosphodiesterase 5-inhibitors (PDE5I) influence age related mortality in diabetic men. METHODS: We studied 857 diabetic men screened for the BLAST study, stratifying them (mean follow-up = 3.8 years) into: (1) Normal T levels/untreated (total T > 12 nmol/L and free T > 0.25 nmol/L), Low T/untreated and Low T/treated; (2) PDE5I/untreated and PDE5I/treated; and (3) statin/untreated and statin/treated groups. The relationship between age and mortality, alone and with T/TRT, statin and PDE5I treatment was studied using logistic regression. Mortality probability and 95%CI were calculated from the above models for each individual. RESULTS: Age was associated with mortality (logistic regression, OR = 1.10, 95%CI: 1.08-1.13, P < 0.001). With all factors included, age (OR = 1.08, 95%CI: 1.06-1.11, P < 0.001), Low T/treated (OR = 0.38, 95%CI: 0.15-0.92, P = 0.033), PDE5I/treated (OR = 0.17, 95%CI: 0.053-0.56, P = 0.004) and statin/treated (OR = 0.59, 95%CI: 0.36-0.97, P = 0.038) were associated with lower mortality. Age related mortality was as described by Gompertz, r2 = 0.881 when Ln (mortality) was plotted against age. The probability of mortality and 95%CI (from logistic regression) of individuals, treated/untreated with the drugs, alone and in combination was plotted against age. Overlap of 95%CI lines was evident with statins and TRT. No overlap was evident with PDE5I alone and with statins and TRT, this suggesting a change in the relationship between age and mortality. CONCLUSION: We show that statins, PDE5I and TRT reduce mortality in diabetes. PDE5I, alone and with the other treatments significantly alter age related mortality in diabetic men.

Polymorphisms in the glutathione S-transferase mu cluster are associated with tumour progression and patient outcome in colorectal cancer.

Glutathione S-transferase (GST) enzymes catalyse the detoxification of by-products of reactive oxygen species and are thus important in cellular defence mechanisms. The GSTs are polymorphic with allelic variants encoding isoforms with functional differences. GST polymorphism has been associated with susceptibility and clinical outcome in patients with cancer. In this retrospective cohort, we have investigated associations between common GSTM1, GSTM3 and GSTP1 polymorphisms with factors known to influence clinical out-come and patient survival in colorectal cancer. Significant linkage disequilibrium was demonstrated between GSTM1 and GSTM3 alleles (P< or =0.001). We identified no significant associations between the GSTP1(Ile105Val105) polymorphism and any clinical outcome parameters or patient survival. However significant associations were demonstrated with mu class GSTs. Those patients who were GSTM1 null presented less frequently with poorly-differentiated tumours (P=0.038). Furthermore, patients who were GSTM3 AA were less likely to present with advanced stage tumours (T-stage, P=0.036 and Dukes' classifications, P=0.012) or distant metastases (P=0.017) when examined alone. Upon further examination of the effect of linkage disequilibrium, we found that, in GSTM1 null individuals, GSTM3 AA (compared with other GSTM3 genotypes combined) had longer disease-free survival (HR=0.54, 95% CI 0.30-0.98, P=0.044). Thus, the GSTM3 AA genotype is associated with improved prognosis especially in those with GSTM1 null. Our findings suggest that the GST mu gene cluster mediates tumour characteristics and survival in patients with colorectal cancer.

Use of fibrates in the metabolic syndrome: A review.

The use of fibrates in the treatment of dyslipidaemia has changed significantly over recent years. Their role appeared clear at the start of this century. The Helsinki Heart Study and Veterans Affairs High-Density Cholesterol Intervention Trial suggested significant benefit, especially in patients with atherogenic dyslipidaemia. However, this clarity disintegrated following the negative outcomes reported by the Bezafibrate Infarction Prevention, Fenofibrate Intervention and Event Lowering in Diabetes and Action to Control Cardiovascular Risk in Diabetes randomised controlled trials. In this review we discuss these and other relevant trials and consider patient subgroups such as those with the metabolic syndrome and those needing treatment to prevent the microvascular complications associated with diabetes in whom fibrates may be useful. We also discuss observations from our group that may provide some explanation for the varying outcomes reported in large trials. The actions of fibrates in patients who are also on statins are interesting and appear to differ from those in patients not on statins. Understanding this is key as statins are the primary lipid lowering agents and likely to occupy that position for the foreseeable future. We also present other features of fibrate treatment we have observed in our clinical practice; changes in creatinine, liver function tests and the paradoxical high density lipoprotein reduction. Our purpose is to provide enough data for the reader to make objective decisions in their own clinical practice regarding fibrate use.

Polymorphism in the nuclear excision repair gene ERCC2/XPD: association between an exon 6-exon 10 haplotype and susceptibility to cutaneous basal cell carcinoma.

Cutaneous basal cell carcinoma (BCC) risk is mediated by interactions between ultraviolet radiation (UVR) and host factors, including DNA repair efficiency. We investigated the association between BCC risk and SNPs in exon 6 (c.466C > A, dbSNP238406:g.C > A; designated C/A156), exon 10 (c.932G > A, dbSNP1799793:g.G > A; designated G/A312), and exon 23 (c.2251A > C, dbSNP13181:g.A > C; designated A/C751) of the nucleotide excision repair gene, XPD (ERCC2; excision repair cross-complementing repair deficiency, complementation 2 [xeroderma pigmentosum D]). XPD genotype frequencies were not significantly different in 509 cases and 379 controls, although AA156 (odds ratio [OR]=0.61, 95% confidence interval [CI]=0.37-1.01, P=0.052) and AA312 (OR=0.65, 95% CI=0.40-1.05, P=0.08) were linked with reduced risk. A156-A312 and A156-A312-A751 haplotype frequencies however, were significantly lower in cases than controls (OR=0.12, 95% CI=0.05-0.31, P < 0.001; OR=0.10, 95% CI=0.03-0.33, P < 0.001). We confirmed the robustness of these findings by showing significant associations of the haplotypes with risk in two randomly selected equal sized groups of cases and controls and, using the false positive report probability (FPRP) approach (FPRP values < 0.001 and < 0.004, respectively). A156-A312 was similarly associated with reduced risk in subgroups, including cases with no family history of skin cancer, with only BCC on the head/neck, and those with a high rate of increase in BCC numbers. The association was not dependent on gender, age, or extent of UVR exposure. A156-A312 was found in 6.3% of controls and the corresponding risk haplotype, C156-G312 (OR=1.65, 95% CI=1.21-2.26, P=0.002) in 35.4% of controls. We interpret these data as showing that XPD SNP mediate susceptibility to BCC.

Ultraviolet radiation, vitamin D and risk of prostate cancer and other diseases.

Most common diseases appear to result from complex, poorly understood interactions between genetic and environmental factors. Relatively few factors have been unequivocally linked with disease risk or outcome. Evidence from various studies using different experimental approaches has been interpreted as showing that, apart from its harmful effects on the pathogenesis of the common skin cancers, ultraviolet radiation (UVR) may exert a beneficial effect on development of various internal cancers and other pathologies. This concept is supported by parallel studies showing that hypovitaminosis D is linked with increased risk of various diseases including insulin resistance and multiple sclerosis. These findings suggest that, first, host factors such as skin pigmentation that affect UVR-induced synthesis of vitamin D and, second, polymorphism in genes that mediate the effectiveness of vitamin D action are susceptibility candidates for a variety of diseases. Collectively, these data suggest the hypothesis that, via effects on vitamin D synthesis, UVR exposure has beneficial effects on susceptibility and outcome to a variety of complex diseases. We describe evidence from studies in various diseases, but mainly from prostate cancer patients, that supports this hypothesis, but we emphasize that, although supportive data are available, the concept is unproven. Indeed, other explanations are possible. However, given the potentially important public health implications of the hypothesis and the potential for the development of novel therapeutic modalities, we believe the concept is worthy of further investigation.

Association of cyclin D1 polymorphism with increased susceptibility to oral squamous cell carcinoma.

We have examined the association of the CCND1 A/G870 polymorphism with susceptibility and outcome in 174 German patients with oral SCC (OSCC). The CCND1 G870 allele frequency was increased in cases (G870=0.65) when compared to controls (n=155, G870=0.54) and the distribution of CCND1 genotypes were significantly different (p=0.014). Using logistic regression, correcting for age, gender and tobacco consumption, an increased frequency of the CCND1 GG870 genotype was observed in the OSCC cases (p=0.025, OR 3.37, 95% CI 1.61-9.80). No significant associations were observed between CCND1 A/G870 and tumour histological factors. Our data suggests that the CCND1 GG870 genotype is associated with increased susceptibility to OSCC. The involvement of cyclin D1 polymorphism in mechanisms of SCC development may differ in the different sub-sites of the head and neck.