The influence of social norms in the context of reducing sugar-sweetened beverages consumption.

OBJECTIVES: This study aimed to examine the factors associated with low sugar-sweetened beverage (SSB) consumption and intention to avoid these products as well as investigate the role of different types of social norms in the adoption of this behaviour. STUDY DESIGN: This study reports the results of a secondary data analysis from a cross-sectional telephone survey. METHODS: A total of 1000 adults were randomly recruited in the province of Québec, Canada, using a random-digit dialling procedure. Eligibility criteria were to be aged between 18 and 64 years; able to answer a questionnaire in French or English; and to reside in the province of Québec. SSB consumption, social norms and variables from the theory of planned behaviour were assessed by means of a questionnaire. Logistic regression analyses were conducted to examine factors associated with behaviour and intention. RESULTS: Consuming <1 SSB per day was significantly associated with intention, perceived behavioural control, and risk perception about tooth decay. Descriptive (perceived prevalence in the close surroundings of one person) and perceived societal norms (perceived broad societal approval/disapproval of the behaviour) were associated with behaviour. All theory of planned behaviour variables (including injunctive norm) and risk perception pertaining to chronic diseases predicted intention to avoid the consumption of ≥1 SSB per day. Sex, age, income, and risk perception pertaining to chronic diseases were associated with perceived societal disapproval of SSB consumption. CONCLUSIONS: This study confirms the importance of social norms in the prediction of SSB consumption but also highlights the need to address motivation and capacities in public health interventions to reduce SSB consumption.

Familial chylomicronemia syndrome: an under-recognized cause of severe hypertriglyceridaemia.

Familial chylomicronemia syndrome (FCS) is a rare autosomal recessive disorder of chylomicron metabolism causing severe elevation of triglyceride (TG) levels (>10 mmol L-1 ). This condition is associated with a significant risk of recurrent acute pancreatitis (AP). AP caused by hypertriglyceridaemia (HTG) has been associated with a worse prognosis and higher mortality rates compared to pancreatitis of other aetiology. Despite its association with poor quality of life and increased lifelong risk of HTG-AP, few healthcare providers are familiar with FCS. Because this condition is under-recognized, the majority of FCS patients are diagnosed after age 20 often after consulting several physicians. Although other forms of severe HTG such as multifactorial chylomicronemia have been associated with high atherosclerotic cardiovascular disease (ASCVD) risk and metabolic abnormalities, ASCVD and metabolic syndrome are not usually observed in FCS patients. Because FCS is a genetic condition, the optimal diagnosis strategy remains genetic testing. The presence of bi-allelic pathogenic mutations in LPL, APOC2, GPIHBP1, APOA5 or LMF1 genes confirms the diagnosis. However, some cases of FCS caused by autoantibodies against LPL or GPIHBP1 proteins have also been reported. Furthermore, a clinical score for the diagnosis of FCS has been proposed but needs further validation. Available treatment options to lower triglycerides such as fibrates or omega-3 fatty acids are not efficacious in FCS patients. Currently, the cornerstone of treatment remains a lifelong very low-fat diet, which prevents the formation of chylomicrons. Finally, inhibitors of apo C-III and ANGPTL3 are in development and may eventually constitute additional treatment options for FCS patients.

Anthropometric measures and their association with risk factors for cardio-metabolic diseases in Kenyan adults.

BACKGROUND: The prevalence of cardio-metabolic diseases (CMD) is drastically increasing worldwide. Anthropometric measures of fat accumulation are correlated with CMD and Metabolic Syndrome (MS), but few studies have addressed this association in sub-Saharan African populations. AIM: To investigate the association between anthropometric features, MS and other CMD risk factors in a population from Kenya. SUBJECTS AND METHODS: In this cross-sectional study including 1405 Kenyans, anthropometric measurements including visceral adipose tissue (VAT) and abdominal subcutaneous adipose tissue (SAT) were carried out. Fasting blood glucose and standard oral glucose tolerance test, fasting serum insulin and plasma lipids were analysed. Homeostatic model assessment of insulin resistance was calculated. Systolic and diastolic blood pressures were measured. RESULTS: CMD risk factors and MS were associated with all anthropometric features, except for high-density lipoprotein cholesterol levels (p < 0.05). The strongest association between MS and anthropometrics was seen with SAT (ß = 1.45 ± 0.32 in men and 0.88 ± 0.14 in women, both p < 0.05). CONCLUSIONS: Anthropometric measures, especially features of central obesity such as VAT and SAT, are relevant indicators of cardio-metabolic health in Kenyan populations. SAT is the strongest predictor of MS. These results highlight the need for further research on the pathological implication of VAT and SAT, in order to understand patterns of fat distribution and cardio-metabolic health among different ethnic groups.

Foot contact angle variability during a prolonged run with relation to injury history and habitual foot strike pattern.

Foot strike pattern and movement variability have each been associated with running injuries. Foot contact angle (FCA) is a common measure of strike pattern. Thus, variability in FCA could be an important running injury risk factor. The purposes of this study were to compare (a) foot contact angle (FCA) and its variability between runners with and without injury history and, (b) FCA variability between habitual rearfoot strike (RFS) and non-RFS runners during a prolonged run. Twenty-three runners with and 21 without injury history participated. Motion capture was used to collect kinematic data during a 40 min treadmill run. Average FCA and its variability were compared between injury groups and among four time points. FCA and its variability were not different between runners with and without injury history or among time points during the run. FCA variability was lower in non-RFS compared to RFS runners (P < 0.001). Lower FCA variability in non-RFS runners may have implications for higher injury risks due to repeated localized tissue loading. Prospective analyses on the effects of lower FCA variability on injury risk are needed.

Effects of submaximal and supramaximal interval training on determinants of endurance performance in endurance athletes.

We compared the effects of submaximal and supramaximal cycling interval training on determinants of exercise performance in moderately endurance-trained men. Maximal oxygen consumption (VO2max ), peak power output (Ppeak ), and peak and mean anaerobic power were measured before and after 6 weeks (3 sessions/week) of submaximal (85% maximal aerobic power [MP], HIIT85 , n = 8) or supramaximal (115% MP, HIIT115 , n = 9) interval training to exhaustion in moderately endurance-trained men. High-intensity training volume was 47% lower in HIIT115 vs HIIT85 (304 ± 77 vs 571 ± 200 min; P < 0.01). Exercise training was generally associated with increased VO2max (HIIT85 : +3.3 ± 3.1 mL/kg/min; HIIT115 : +3.3 ± 3.6 ml/kg/min; Time effect P = 0.002; Group effect: P = 0.95), Ppeak (HIIT85 : +18 ± 9 W; HIIT115 : +16 ± 27 W; Time effect P = 0.045; Group effect: P = 0.49), and mean anaerobic power (HIIT85 : +0.42 ± 0.69 W/kg; HIIT115 : +0.55 ± 0.65 W/kg; Time effect P = 0.01; Group effect: P = 0.18). Six weeks of submaximal and supramaximal interval training performed to exhaustion seems to equally improve VO2max and anaerobic power in endurance-trained men, despite half the accumulated time spent at the target intensity.

Activation of PPAR gamma receptors reduces levodopa-induced dyskinesias in 6-OHDA-lesioned rats.

Long-term administration of l-3,4-dihydroxyphenylalanine (levodopa), the mainstay treatment for Parkinson's disease (PD), is accompanied by fluctuations in its duration of action and motor complications (dyskinesia) that dramatically affect the quality of life of patients. Levodopa-induced dyskinesias (LID) can be modeled in rats with unilateral 6-OHDA lesions via chronic administration of levodopa, which causes increasingly severe axial, limb, and orofacial abnormal involuntary movements (AIMs) over time. In previous studies, we showed that the direct activation of CB1 cannabinoid receptors alleviated rat AIMs. Interestingly, elevation of the endocannabinoid anandamide by URB597 (URB), an inhibitor of endocannabinoid catabolism, produced an anti-dyskinetic response that was only partially mediated via CB1 receptors and required the concomitant blockade of transient receptor potential vanilloid type-1 (TRPV1) channels by capsazepine (CPZ) (Morgese et al., 2007). In this study, we showed that the stimulation of peroxisome proliferator-activated receptors (PPAR), a family of transcription factors activated by anandamide, contributes to the anti-dyskinetic effects of URB+CPZ, and that the direct activation of the PPARγ subtype by rosiglitazone (RGZ) alleviates levodopa-induced AIMs in 6-OHDA rats. AIM reduction was associated with an attenuation of levodopa-induced increase of dynorphin, zif-268, and of ERK phosphorylation in the denervated striatum. RGZ treatment did not decrease striatal levodopa and dopamine bioavailability, nor did it affect levodopa anti-parkinsonian activity. Collectively, these data indicate that PPARγ may represent a new pharmacological target for the treatment of LID.

Does Statin or ASA Affect Survival When Prostate Cancer Is Treated with External Beam Radiation Therapy?

Background. Prior studies evaluating the effect of statins or acetylsalicylic acid (ASA) on the survival of men receiving prostate cancer were treatment have reported conflicting results, and have not adjusted for comorbidity. Our aim is to investigate the influence of statins and ASA on prostate cancer survival, when comorbidity is adjusted for, in men treated with external beam radiation therapy (EBRT) for prostate cancer. Methods. A cohort of 3851 patients with prostate cancer treated with curative EBRT ± androgen deprivation therapy (ADT) between 2000 and 2007. Stage, treatment, medication use, and Charlson comorbidity index (CCI) scores were analyzed. Results. Median followup was 8.4 years. Mean age was 70.3 years. Neoadjuvant ADT was used in 67%. Statins were used in 23%, ASA in 24%, and both in 11%. Comorbidity scores were 0 in 65%, 1 in 25%, and ≥2 in 10% of patients. Statin and ASA use were associated with increased age and comorbidity. Although statin and ASA use were significantly associated with improved prostate cancer specific survival (PCSS) on univariate analysis, neither were on multivariate analysis. Conclusion. Neither statin nor ASA use impacted PCSS on multivariate competing risks analysis. Survival was impacted by increased comorbidity as well as statin and ASA use.

Dietary composition alters gentamicin-induced nephrotoxicity in rats.

Previous studies have shown temporal variations in gentamicin-induced renal toxicity characterized by a peak when administered during the resting period and a trough during the active period. This time-dependent toxicity was also altered according to the macronutrient composition of dietary regimens offered to female rats. In the present study, adult female Sprague-Dawley rats were adapted to semipurified isocaloric diets containing 20% casein or soy-protein (10% fat each) or to a standard chow diet (18.1% mixed proteins; 4.5% fat). The animals were then chronically treated for 10 days with a nephrotoxic dose of gentamicin sulfate (40 mg/kg/day ip) or a saline solution administered in the middle of their resting period (1200 h) or in the middle of their activity period (0000 h). Body weights of rats injected in the middle of their resting period decreased over the last 6 days of gentamicin treatment. Total 12-h light and 12-h dark food intakes were decreased in gentamicin-treated rats. Rats fed the standard chow diet had significantly lower corticocellular regeneration, serum creatinine and blood urea nitrogen compared to those fed the casein- and soy-containing diets. The present study demonstrates that chronic gentamicin-induced renal toxicity varies temporally according to the time of administration and that a mixed protein diet containing a lower fat level can protect against gentamicin-induced nephrotoxicity.

Thrombogenicity of radiofrequency ablation procedures: what factors influence thrombin generation?

AIMS: Thromboembolic complications have been reported after radiofrequency ablation but the low incidence of overt clinical events has been a limitation to the study of factors affecting thrombogenic risk. The aim of this study was to determine whether radiofrequency ablation has a procoagulant effect and to examine variables that affect thrombio generation. METHODS AND RESULTS: Thirty-seven consecutive patients who underwent radiofrequency ablation were studied prospectively. Blood samples were assayed for thrombin-antithrombin III (TAT) and d-dimer (DD) at five different time points: (1) baseline; (2) after sheath insertion; (3) after electrophysiological study but before radiofrequency ablation; (4) at completion of the procedure; and (5) 24 h post-procedure. TAT levels were within the normal range at baseline and increased significantly after sheath insertion from 2.1 +/- 1.2 microg l(-1) to 13.3 +/- 16.0 microg l(-1) (P<0.01). Levels increased further to 24.0 +/- 19.9 microg l(-1) (P<0.01) after electrophysiological study but did not increase after radiofrequency ablation. TAT normalized at 24 h. DD increased significantly from baseline values (230.2 +/- 176.8 ng ml(-1)) to 285.4 +/- 237.4 ng ml(-1) (P=0.019) after sheath insertion. There was a further significant increase after electrophysiological study to 423.4 +/- 324.3 ng ml(-1) (P<0.01), and a slight but non-significant increase to 464.4 +/- 307.4 ng ml(-1) after radiofrequency ablation (P=0.159). DD remained elevated at 24 h. Procedure duration was the only variable that correlated with the relative increase in TAT and DD. The patients with the longest procedure durations had more catheters inserted, more radiofrequency applications and largely consisted of accessory bypass tract-mediated tachycardias. Heparin administration significantly blunted the relative increase in TAT after radiofrequency ablation (P=0.005). CONCLUSION: Radiofrequency ablation procedures confer an increased risk of thrombosis. Catheterization and diagnostic study contribute largely to the thrombogenic stimulus. Thrombogenicity is increased in prolonged, complex procedures and is decreased in patients who have been administered heparin during the procedure.

The influence of marital adjustment on 3-year left ventricular mass and ambulatory blood pressure in mild hypertension.

BACKGROUND: Of psychosocial stressors, job strain has been associated with a sustained increase in blood pressure. The impact of marital factors on blood pressure and target organ has not been explored. OBJECTIVES: To evaluate whether marital adjustment, measured at baseline by self-report (Dyadic Adjustment Scale) influences left ventricular mass index (LVMI) and ambulatory blood pressure measured over 3 years in patients with mild hypertension. METHODS: A prospective cohort study was conducted on 103 cohabiting males or females, including 72 with technically adequate echocardiograms, who at baseline were unmedicated, employed, and living with a significant other, all for a minimum of 6 months and had repeated elevated office diastolic blood pressure. MAIN OUTCOME MEASURES: Left ventricular mass by M-mode echocardiography indexed to body surface area and blood pressure were measured by ambulatory blood pressure every 15 minutes (daytime) and hourly between 11 PM and 7 AM. RESULTS: Marital adjustment, smoking, drinking, and baseline LVMI contributed significantly to the prediction of 3-year LVMI (semipartial correlation, sr(2) = 0.04, 0.07, 0.03, and 0.22; P =.03,.008,.08, and <.001, respectively) together accounting for 36% of the total variability in follow-up LVMI. Three-year ambulatory blood pressure measures were not significantly related to marital adjustment but there were correlations with Dyadic Adjustment Scale subscales. Low or high levels of spousal contact during 3-year ambulatory blood pressure monitoring were associated with an increase or decrease of 3-year, 24-hour diastolic blood pressure, consistent with the quality of marital adjustment (P =.04) or marital satisfaction (Dyadic Adjustment Scale subscale, P =.008). CONCLUSIONS: In a cohort of subjects with mild essential hypertension, marital adjustment had an influence on 3-year LVMI. Depending on the quality of marital adjustment, spousal contact at 3 years was associated with an increase or decrease of 3-year diastolic blood pressure. Confirmation of these results, including objective marital assessment and the participation of normotensive subjects, is required. Arch Intern Med. 2000;160:3453-3458.

Role of gender and personality on quality-of-life impairment in intermittent atrial fibrillation.

Patients with atrial fibrillation (AF) report impaired health-related quality of life (QOL). Differences between men and women with AF have not been described and personality attributes such as somatization (tendency to amplify benign bodily sensations) may mediate potential gender differences in QOL. Patients with AF (n = 264, 59% men) who participated in the Canadian Trial of Atrial Fibrillation (n = 403) completed validated QOL questionnaires at baseline, 3 months, and 12 months after antiarrhythmic drug treatment. Women were significantly older than men and a greater proportion had hypertension, but other cardiac variables did not differ between women and men. At baseline, after controlling for significant clinical and demographic factors, women reported worse physical health (p = 0.002) and functional capacity (p < 0.001), but not mental health or general well-being. Women also had more frequent and severe cardiac symptoms than men (both p < 0.001). Physical health improved significantly from baseline to 3 months for women (p = 0.002), but not for men (p = 0.066). Conversely, mental health improved for men (p = 0.007), but not for women. Cardiac symptom frequency and severity improved over time for women and men (all p < 0.001). Tendency to somatize predicted poor QOL, and women had higher scores than men (p = 0.023). However, after controlling for somatization, women still had worse physical function, functional capacity, and symptom burden than men. Independent of cardiac disease severity and age, women with AF had significantly more impaired QOL than men, specifically on domains related to physical rather than emotional functioning. Personality attributes may have a role in influencing QOL outcomes.

The impairment of health-related quality of life in patients with intermittent atrial fibrillation: implications for the assessment of investigational therapy.

OBJECTIVES: We sought to assess the impact of intermittent atrial fibrillation (AF) on health-related quality of life (QoL). BACKGROUND: Intermittent AF is a common condition with little data on health-related QoL questionnaires to guide investigational therapies. METHODS: Outpatients from four centers, with documented AF (n = 152), completed validated QoL questionnaires (Medical Outcomes Study Short Form 36 [SF-36], Specific Activity, Symptom Checklist, Illness Intrusiveness and University of Toronto AF Severity Scales). Comparison groups were made up of healthy individuals (n = 47) and four cardiac control groups: published (n = 78) and created for study (n = 69) percutaneous transluminal coronary angioplasty (PTCA); published heart failure (n = 216) and published postmyocardial infarction (MI) (n = 107). RESULTS: Across all domains of the SF-36, AF patients reported substantially worse QoL than healthy controls (1.3 to 2.0 standard deviation units), with scores of 24%, 23%, 16% and 30% lower than healthy individuals on measures of physical and social functioning, mental and general health, respectively (all p < 0.001). Patients with AF were either significantly worse (p < 0.05, published controls) or as impaired (study controls) as either PTCA or post-MI patients on all domains of the SF-36 and the same as heart failure controls on SF-36 psychological subscales. Patients with AF were as impaired or worse than study PTCA controls on measures of illness intrusiveness, activity limitations and symptoms. Associations between objective disease indexes and subjective QoL measures had poor correlations and accounted for <6% of the total variability in QoL scores. CONCLUSIONS: Quality of life is as impaired in patients with intermittent AF as in patients with significant structural heart disease. Patients' perception of QoL is not dependent on the objective measures of disease severity that are usually employed.

Effect of quipazine, a selective 5-HT3 agonist, on dietary self-selection of different macronutrient diets in male and female rats.

Macronutrient intakes, 2h and 12h, following administration of a selective 5-HT3 agonist, quipazine, N methyl, dimaleate (QUIPAZINE; 2.5, 5.0 and 7.5 mg/kg, i.p.) at dark onset were examined in three groups of adult male and female Wistar rats fed different sources of the three macronutrients: Group 1 (casein, corn starch, safflower oil), Group 2 (egg protein, corn starch/sucrose, lard) and Group S (casein hydrolysate, maltose dextrin, butter). QUIPAZINE decreased total food intake only in female rats from Group 1 (2 h) at a dose of 7.5 mg/kg and Group 2 (2h and 12h) with doses of 2.5 and 7.5 mg/kg. Intakes from corn starch and corn starch/sucrose diet (12h) were reduced in male and female rats, respectively, with doses of 2.5 and 7.5 mg/kg of QUIPAZINE. In conclusion, when provided with different sources of the three macronutrients, quipazine injection reduces specifically carbohydrate ingestion from corn starch-containing diets in male and female rats. Thus, the nature of the macronutrient source is of major importance to assess the effect of a drug on nutrient-specific selection.

Inappropriate therapy from atrial fibrillation and sinus tachycardia in automated implantable cardioverter defibrillators.

BACKGROUND: Inappropriate therapy from supraventricular tachyarrhythmias (atrial fibrillation [AF] and sinus tachycardia [ST]) in patients with implanted cardioverter defibrillators is a major challenge. We tested the performance of stability algorithms from 3 manufacturers for episodes of inappropriate therapy delivered because of AF and an onset algorithm for all episodes of inappropriate therapy caused by ST. METHODS: Therapy was classified as caused by ventricular tachycardia (VT), ST, or AF from review of stored intracardiac electrograms, history, clinical information, and R-R data before study inception. By using 30 to 60 R-R intervals before therapy, sensitivity and specificity for a family of stability values and percentage of onset values were calculated for each manufacturer and receiver operating characteristic curves generated. RESULTS: Of the 217 patients monitored, 62 (29%) received inappropriate therapy, and 40 had complete R-R information available. Of the 40 patients, 21 patients received therapy for AF, 19 for ST, and 1 patient for noise; 15 (38%) also received appropriate therapy for VT. We analyzed 83 episodes of VT from 18 patients, 94 episodes of AF from 21 patients, and 56 episodes of ST from 19 patients. Specificity, in the clinically relevant sensitivity range of >/=95%, was comparable across manufacturers at about 40%. An onset value of 80% was associated with 91% sensitivity and 95% specificity for the specific algorithm tested. CONCLUSIONS: Inappropriate therapy is a common problem in implantable cardiac defibrillators. The performance of the stability algorithms used to differentiate AF from VT was less than ideal, though comparable across manufacturers. The onset algorithm accurately differentiates ST from VT.

Effect of physiological mechanical perturbations on intact human myocardial repolarization.

OBJECTIVE: The objective of this study was to investigate the relationship between acute decreases in right ventricular volume during Valsalva strain (with resultant changes in autonomic neural tone) and measures of local endocardial repolarization time independent of heart rate and autonomic neural tone. METHODS: Patients implanted with a stimulus to T wave (Stim-T) sensing pacemaker specially adapted to output a validate measure of beat to beat local repolarization (n = 9) performed Valsalva manoeuvers (40 mmHg for 15 s) while paced at a cycle length of 500 ms. Stim-T intervals were measured before and after autonomic blockade (Block: 0.03 mg/kg i.v. atropine +/- 0.15 mg/kg propranolol). Right ventricular end diastolic volume was estimated by simultaneous 2D-echocardiography. RESULTS: Without autonomic blockade, compared to baseline, repolarization significantly prolonged during Valsalva strain (1.1 +/- 0.7%) and shortened during release (-1.4 +/- 1.0%). After block, strain related repolarization prolongation was also observed (1.0 +/- 0.6%), with significantly less release related repolarization shortening (-0.8 +/- 0.8%) compared to pre-block (P < 0.05). Right ventricular end diastolic volume decreased during strain by 11 +/- 10 and 9 +/- 16% from baseline, pre- and post-block respectively (P < 0.05). CONCLUSION: In a chronically instrumented human model, an acute physiologic volume reduction modestly prolongs right ventricular repolarization independent of changes in rate or autonomic tone.