Non-fasting Individuals Research Articles

Ramadan-Induced Lifestyle Changes: Effects on Sleep and Physical Activity in Non-Fasting Type 1 Diabetes Patients

ObjectivesIn this study we aimed to identify sleep patterns, physical fitness, and barriers to physical activity (PA) during Ramadan observance in a cohort of nonfasting individuals with type 1 diabetes (T1D). MethodsSixty-one nonfasting patients with T1D, age 28.34±9.43 years, ranging from 15 to 54 years, completed questionnaires before and during Ramadan. The questionnaires included 3 assessment instruments: the Barriers to Physical Activity in Type 1 Diabetes (BAPAD1), the Pittsburgh Sleep Quality Index (PSQI), and the International Physical Activity Questionnaire. ResultsDuring Ramadan, there was no significant change in BAPAD1 scores compared to before Ramadan (p=0.378). The primary barriers encompassed hypoglycemia risk, work schedules, diabetes control, and fatigue. Moreover, subjective sleep quality deteriorated during Ramadan compared to the pre-Ramadan period (p<0.001). Sleep duration decreased by 58 minutes (p<0.01) and was associated with later bedtimes and more awakenings. There was a notably decrease in PA levels (p=0.042), particularly for vigorous activities (p=0.017), whereas sedentary time showed a significant increase (p=0.008). ConclusionsRamadan observance did not affect barriers to PA in individuals with T1D despite alteration of sleep patterns and PA levels. Lifestyle alterations associated with Ramadan observance significantly impact individuals with T1D who are not fasting, resulting in reduced PA, shortened sleep duration, and increased sedentary time.

The effect of observing religious or faith-based fasting on cardiovascular disease risk factors: A systematic review and meta-analysis

AimsCardiovascular diseases (CVD) are the leading cause of death worldwide. Fasting is common in many religions and is associated with health benefits. This systematic review to compares the impact of different religious fasting practices, on risk of cardiometabolic diseases. Data synthesisThe search covered five databases following PRISMA guidelines to identify papers published in English from inception to March 2023 (updated January 2024). Inclusion criteria were healthy adults in observational studies, who engaged in religious fasting practices, studies were included where data on matched non-fasting individuals was available. Outcomes were systolic and diastolic blood pressure, body mass index (BMI), triglycerides, total cholesterol (TC), low-density lipoprotein cholesterol (LDLc), high-density lipoprotein cholesterol (HDLc), and fasting plasma glucose levels. A meta-analysis was conducted, and the review was registered (CRD42022352197). Fourteen studies were met the inclusion criteria with ten studies data being suitable for meta-analysis, reporting on 755 adults participating in fasting practices and 661 non-fasting controls. Religious fasting was associated with a reduction in BMI (−0.40 kg/m2, 95% CI [-0.70, −0.10], p < 0.01). Observance of Ramadan fasting was associated with decreased systolic blood pressure (−3.83 mmHg, 95% CI [-7.44, −0.23], p = 0.04). The observance of Orthodox Christian fasting was associated with a reduction in TC (−0.52 mmoL/l, 95%CI [–0.64, −0.39], p < 0.01). No difference was found for the other outcomes. ConclusionThis review found religious fasting practices which were associated with a reduction in some biomarkers of cardiometabolic diseases risk. Further research on other fasting practices is needed due to limited data.

The Christian Orthodox Church Fasting Diet Is Associated with Lower Levels of Depression and Anxiety and a Better Cognitive Performance in Middle Life.

Lifestyle choices significantly influence mental health in later life. In this study we investigated the effects of the Christian Orthodox Church (COC) fasting diet, which includes long-term regular abstinence from animal-based products for half the calendar year, on cognitive function and emotional wellbeing of healthy adults. Two groups of fasting and non-fasting individuals were evaluated regarding their cognitive performance and the presence of anxiety and depression using the Mini Mental Examination Scale, the Hamilton Anxiety Scale, and the Geriatric Depression Scale (GDS), respectively. Data on physical activity, smoking, and vitamin levels were collected and correlated with mental health scoring. Negative binomial regression was performed to examine differences in the GDS scores between the two groups. Significantly lower levels of anxiety (7.48 ± 4.98 vs. 9.71 ± 5.25; p < 0.001) and depression (2.24 ± 1.77 vs. 3.5 ± 2.52; p < 0.001), along with better cognitive function (29.15 ± 0.79 vs. 28.64 ± 1.27; p < 0.001), were noticed in fasting compared to non-fasting individuals. GDS score was 31% lower (Incidence Rate Ratio: 0.69, 95% Confidence Interval: 0.56–0.85) in the fasting group compared to the control, while vitamin and ferrum levels did not differ. The COC fasting diet was found to have an independent positive impact on cognition and mood in middle-aged and elderly individuals.

Erythrocyte Ascorbate Is a Potential Indicator of Steady-State Plasma Ascorbate Concentrations in Healthy Non-Fasting Individuals.

Plasma vitamin C concentrations fluctuate in response to recent dietary intake; therefore levels are typically determined in the fasting state. Erythrocyte ascorbate concentrations have been shown to be similar to plasma levels, but little is known about the kinetics of ascorbate accumulation in these cells. In this study, we investigated ascorbate uptake into erythrocytes after dietary supplementation with vitamin C and compared it to changes in plasma ascorbate concentrations. Seven individuals with baseline fasting plasma vitamin C concentrations ≥ 50 µmol/L were depleted of vitamin C-containing foods and drinks for one week, and then supplemented with 250 mg vitamin C/day in addition to resuming their normal diet. Fasting or steady-state plasma ascorbate concentrations declined to almost half of their baseline concentration over the week of vitamin C depletion, and then returned to saturation within two days of beginning supplementation. Erythrocyte ascorbate concentrations exhibited a very similar profile to plasma levels, with values ~76% of plasma, and a strong linear correlation (r = 0.89, p < 0.0001). Using a pharmacokinetic study design in six individuals with baseline fasting plasma vitamin C concentrations ≥50 µmol/L, we also showed that, unlike plasma, which peaked between 2 and 4 h following ingestion of 200 mg of vitamin C, erythrocyte ascorbate concentrations did not change in the six hours after supplementation. The data from these two intervention studies indicate that erythrocyte ascorbate concentration provides a stable measure of steady-state plasma ascorbate status and could be used to monitor ascorbate status in healthy non-fasting individuals.

Associations of a metabolic syndrome severity score with coronary heart disease and diabetes in fasting vs. non-fasting individuals

Background and aimsMany traditional assessments of risk for coronary heart disease (CHD) and diabetes require laboratory studies performed after an 8-h fast. We assessed whether metabolic-syndrome (MetS) severity would remain linked to future CHD and diabetes even when assessed from non-fasting samples. Methods and resultsParticipants in the Atherosclerosis Risk in Communities study were assessed at 4 visits and followed for 20-years of adjudicated CHD outcomes. We used Cox proportional-hazard models (for 20-year CHD outcomes) and logistic regression (for 9-year diabetes outcomes) to compare incident disease risk associated with a race/ethnicity-specific MetS-severity Z-score (MetS-Z) calculated in participants who were fasting (≥8 h) or non-fasting. All analyses were adjusted for sex, race, education, income and smoking. MetS Z-scores were overall similar between participants who were always fasting vs. those non-fasting at Visits 1–3 (all values −0.1 to 0.4), while MetS-Z for participants who were non-fasting at Visit-4 were higher at each visit. Baseline MetS-Z was linked to future CHD when calculated from both fasting and non-fasting measurements, with hazard ratio (HR) for fasting MetS-Z 1.53 (95% confidence interval [CI] 1.42, 1.66) and for non-fasting 1.28 (CI 1.08, 1.51). MetS-Z at Visit-1 also remained linked to future diabetes when measured from non-fasting samples, with odds ratio for fasting MetS-Z 3.10 (CI 2.88, 3.35) and for non-fasting 1.92 (CI 1.05, 3.51). ConclusionsMetS-Z remained linked to future CHD and diabetes when assessed from non-fasting samples. A score such as this may allow for identification of at-risk individuals and serve as a motivation toward interventions to reduce risk.

The effect of Ramadan fasting on renal functions in patients with chronic kidney disease

Abstract Objective We aimed to investigate the effects of Ramadan fasting on renal functions in patients with stage 3 and 4 chronic kidney disease. Materials and methods The study was conducted in Ramadan month which was between June and July. Patients were evaluated before Ramadan, the week immediately following the end of the Ramadan, and 3 and 6 months after Ramadan. Results Twenty-four fasting (mean age of 68 ± 13 years) and 55 non-fasting individuals (mean age of 69 ± 9 years) were included in this study. There was no statistically significant difference for creatinine levels in the first week after Ramadan in both groups compared to levels before Ramadan (p = 0.070, p = 0.470, respectively). The groups were compared according to the criteria of deterioration in renal function (reduction of 25% in GFR and 30% increase in serum creatinine levels). There were no statistically significant differences between the two groups according to these two criteria (p = 0.452, p = 0.660, respectively). In univariate and multivariate logistic regression analysis, the presence of diabetes mellitus and proteinuria were found to be independent risk determinants of renal dysfunction. Conclusion Patients with diabetes mellitus and prominent proteinuria may constitute critical patient groups for renal function deterioration during Ramadan fasting.

SUN-064 Associations of a Metabolic Syndrome Severity Score with Future Coronary Heart Disease (CHD) and Diabetes in Fasting vs. Non-Fasting Individuals

BACKGROUND: Many traditional assessments of risk for coronary heart disease (CHD) and diabetes require laboratory studies performed after at least an 8-hour fast. However, obtaining fasting samples is less convenient and may result in fewer opportunities for risk assessment and targeted treatment. We hypothesized that metabolic syndrome (MetS) severity would remain linked to future CHD and diabetes even when assessed from non-fasting samples. METHODS: Participants in the Atherosclerosis Risk in Communities study were assessed at 4 visits and followed for 20-years of adjudicated CHD outcomes. We used a race/ethnicity-specific MetS severity Z-score (MetS-Z) calculated from the five traditional components of MetS: waist circumference, systolic blood pressure, HDL, triglycerides and glucose. In prior studies, this Z-score—as calculated from fasting samples—was associated with future CHD and diabetes independent of the individual MetS components. In the current analysis, we assessed risk of adjudicated CHD outcomes using Cox proportional hazard models for baseline MetS-Z calculated from a) fasting (≥8 hours) samples at Visit 1 or b) non-fasting samples at any of the 4 study visits. We assessed incident diabetes risk using logistic regression for fasting vs. non-fasting samples from Visit 1 for risk of diabetes by Visit 4. All analyses were adjusted for sex, race, education, income and current smoking. RESULTS: MetS Z-scores across visits were overall similar between fasting and non-fasting groups (all values when drawn from both fasting and non-fasting samples -0.1 - 0.4), with the exception of individuals non-fasting at Visit 4, who had higher MetS-Z values already at Visit 1. MetS-Z scores were linked to future CHD when calculated from both fasting and non-fasting measurements, with hazard ratio (HR) for fasting MetS-Z 1.53 (95% confidence interval [CI] 1.42, 1.66) and for non-fasting MetS-Z 1.28 (CI 1.08, 1.51). MetS-Z at Visit 1 also remained linked to future diabetes when measured from non-fasting samples, with HR for fasting MetS-Z 3.10 (CI 2.88, 3.35) and for non-fasting MetS-Z 1.92 (CI 1.05, 3.51). CONCLUSIONS: As a marker of long-term risk for chronic disease, MetS-Z remained linked to future CHD and diabetes when assessed from non-fasting samples. A score such as this, calculated through the electronic health record, may allow for identification of at-risk individuals and serve as a motivation toward interventions to improve risk.

High rate of acute pancreatitis during the Ramadan fast.

During the Ramadan fast Muslims celebrate a month of prayer, dawn-to-dusk fasting, and nightly feasts. We aimed to assess whether acute pancreatitis (AP) is more common during the Ramadan fast in individuals who celebrate it. The study was carried out at the emergency department of Rabin Medical Center, Israel. We compared the occurrence of AP in a fasting population and a nonfasting population during the Ramadan versus the rest of the year. Over the 10-year study period, 1167 patients were admitted to the emergency department with AP. Of these, 1069 (91.6%) were nonfasting and 98 (8.4%) were fasting. Of these, 17/98 (17.3%) fasting patients and 95/1069 (8.8%) nonfasting patients were admitted with AP during the Ramadan [relative risk: 1.12; 95% confidence interval (CI): 1.004-1.2; odds ratio (OR): 2.15; 95% CI: 1.23-3.8; P=0.01]. During the Ramadan, the rate of AP out of referrals was 0.1% (17/15 068) in fasting patients versus 0.004% (95/213 913) in nonfasting individuals (OR: 2.54; 95% CI: 1.5-4.25). During the other months of the year, the rate of AP out of referrals was 0.009% (81/86 072) in fasting patients versus 0.008% (974/1 202 405) in nonfasting individuals (OR: 1.16; 95% CI: 0.92-1.45; P<0.001). We found a high rate of AP in the fasting population during the Ramadan. Physicians should be aware of this link and suspect it for fasting patients presenting with epigastric pain during the Ramadan fast.

Effect of fasting on 24-h blood pressure values of individuals with no previous history of hypertension.

We aimed to analyze the difference in 24-h blood pressure values during Ramadan of fasting and nonfasting individuals with no previous history of hypertension. This study was planned as a multicenter research study in the cities of Izmit, Zonguldak, Sivas, and Adana. The percentage changes in the blood pressure of the patients were calculated from their blood pressure measurements at 0 h while they were resting. A Food Frequency Questionnaire was filled out by all participants. Forty patients were included in the fasting group and 55 patients were included in the nonfasting group in the study. There was a difference between the two groups in percent changes of systolic measurements performed at the 4th (5% difference and P=0.020), 13th (6% difference and P=0.015), 14th (10% difference and P=0.017), 18th (9% difference and P=0.027), 19th (9% difference and P=0.020), and 20th (6% difference and P=0.014) hours with respect to the baseline measurement at the 0 h. There was a difference between the fasting and nonfasting groups in the Fasting Food Questionnaire results. Meat consumption was significantly higher in the fasting group. A systolic blood pressure increase in fasting patients was observed in measurements at 18:00, 19:00, and 20:00 h. We believe that an increase of more than 10% in blood pressure at the time of iftar is an important result of our study in terms of the meal preferences of the individuals under risk.

Non\u2013high-density lipoprotein fractions are strongly associated with the presence of metabolic syndrome independent of obesity and diabetes: a population-based study among Iranian adults

BackgroundNon-HDL-C as a valuable predictor of premature atherosclerosis, coronary events like first Myocardial infarction and cardiovascular mortality has a high accuracy of measurement both in fasting and non-fasting individuals. Metabolic syndrome (MetS) can promote the development of diabetes mellitus, endothelial dysfunction and atherosclerosis. A common pathway for cross linking of metabolic abnormalities and non-HDL-C has been suggested. In this study we aimed to describe the potential association between non-HDL cholesterol fractions and metabolic syndrome.MethodsData of third national surveillance of the risk factors of non-communicable diseases (SuRFNCD-2007) were analyzed. We defined metabolic syndrome (MetS) according to the Adult Treatment Panel III (ATPIII) and International Diabetes Federation (IDF) criteria for 2125 subjects aging 25–64 years. The receiver operating characteristic (ROC) curves were used to determine the optimal cut-points for the diagnosis of MetS. The curves were depicted for non–high-density lipoprotein cholesterol (non-HDL-C) and difference of total non-HDL-C and LDL-C (Differential cholesterol or Diff-C) as predictors of MetS. Logistic regression was also performed in a complex sample analysis scheme.ResultsThe area under the curve (AUC) with 95% Confidence intervals of total non-HDL-C was computed. Values were 0.693 (0.670-0.715) for IDF-defined MetS and 0.719 (0.697-0.740) for ATPIII criteria. The optimal non-HDL-C cut-point we recommend for both criteria is 153.50 mg/dl (sensitivity: 75.7%, specificity: 57.2%, with ATPIII; sensitivity: 73.2%, specificity: 57.1%, with IDF). Using IDF criteria, the accuracy of predictors were greater in non-diabetic subjects. AUC of Diff-C in DM (−) vs. DM (+) were 0.786 (0.765-0.807) vs. 0.627(0.549-0.705). Adults with high non–HDL-C were 4.42 times more likely to have ATPIII-defined MetS (≥190 vs. < 190 mg/dL). Elevated Diff-C corresponded to increased risk of the MetS (ORs: 10.71 and 26.29 for IDF and ATP III criteria, respectively. All P-values <0.001).ConclusionsA significant robust association exists between non-HDL-C and MetS whether applying conventional or new thresholds.

Short-term NO2 exposure is associated with long-chain fatty acids in prospective cohorts from Augsburg, Germany: results from an analysis of 138 metabolites and three exposures.

Short-term exposure to air pollution is associated with morbidity and mortality. Metabolites are intermediaries in biochemical processes, and associations between air pollution and metabolites can yield unique mechanistic insights. We used independent cross-sectional samples with targeted metabolomics (138 metabolites across five metabolite classes) from three cohort studies, each a part of the Cooperative Health Research in the Region of Augsburg (KORA). The KORA cohorts are numbered (1 to 4) according to which survey they belong to, and lettered S or F according to whether the survey was a baseline or follow-up survey. KORA F4 (N = 3044) served as our discovery cohort, with KORA S4 (N = 485) serving as the primary replication cohort. KORA F4 and KORA S4 were primarily fasting cohorts. We used the non-fasting KORA F3 (N = 377) cohort to evaluate replicated associations in non-fasting individuals, and we performed a random effects meta-analysis of all three cohorts. Associations between the 0-4-day lags and the 5-day average of particulate matter (PM)2.5, NO2 and ozone were modelled via generalized additive models. All air pollution exposures were scaled to the interquartile range, and effect estimates presented as percent changes relative to the geometric mean of the metabolite concentration (ΔGM). There were 10 discovery cohort associations, of which seven were lysophosphatidylcholines (LPCs); NO2 was the most ubiquitous exposure (5/10). The 5-day average NO2-LPC(28:0) association was associated at a Bonferroni corrected P-value threshold (P < 1.2x10-4) in KORA F4 [ΔGM = 11.5%; 95% confidence interval (CI) = 6.60, 16.3], and replicated (P < 0.05) in KORA S4 (ΔGM = 21.0%; CI = 4.56, 37.5). This association was not observed in the non-fasting KORA F3 cohort (ΔGM = -5.96%; CI = -26.3, 14.3), but remained in the random effects meta-analysis (ΔGM = 10.6%; CI = 0.16, 21). LPCs are associated with short-term exposure to air pollutants, in particular NO2 Further research is needed to understand the effect of nutritional/fasting status on these associations and the causal mechanisms linking air pollution exposure and metabolite profiles.

Abstract 13397: Determining the Optimal Cutpoint Value for the Diagnosis of Hypertriglyceridemia in the Nonfasting Population

Background: Nonfasting triglycerides may be superior to fasting triglycerides at predicting CVD. However, guideline cutpoints are based on fasting triglycerides. We aimed to determine the optimal clinical cutpoint for nonfasting triglycerides. Methods: Among 26,509 apparently healthy women, nonfasting blood samples (&lt;8 hours since last meal) were obtained from 6,391 participants who were prospectively followed for up to 17 years for incident CVD (MI, ischemic stroke, CABG/PTCA, CVD death). The optimal diagnostic threshold for nonfasting triglycerides was determined by univariate logistic regression model using c-statistics for triglycerides between 100-300 mg/dL, with 10-fold cross-validation and bootstrapping in multivariable models. In addition, we tested the proposed nonfasting cutpoints of 175 mg/dL (European Atherosclerosis Society), 180 mg/dL (Athens Expert Panel), and 200 mg/dL (AHA). Results: The optimal threshold was identified as 175 mg/dL (Table). Performance of this optimal threshold was evaluated using 10-fold cross validation and bootstrapping in multivariable models that included age, smoking, blood pressure, hormone use, menopausal status, lipids, diabetes, BMI, and CRP. The adjusted hazard ratio (HR) for nonfasting triglycerides ≥ vs &lt;175 mg/dL predicting incident CVD events was 1.69 (95% CI, 1.34-2.13, p&lt;0.001). Adjusted HRs for triglycerides ≥ vs &lt;175 mg/dL measured 0-4 and 4-8 hours since last meal were 1.73 (1.27-2.36, p&lt;0.001) and 1.63 (1.15-2.32, p=0.006), respectively. Conclusion: This is the first study to identify a diagnostic threshold for nonfasting hypertriglyceridemia, finding an optimal cutpoint of 175 mg/dL. Of note, the currently recommended AHA cutpoint for nonfasting triglycerides of 200 mg/dL had substantially lower sensitivity and could under-diagnose hypertriglyceridemia among nonfasting individuals.

Preanalytical factors of importance for measurement of Chromogranin A

BackgroundStudies indicate that fasting and diurnal variation can influence serum Chromogranin A (CgA) concentrations and furthermore, stability of the CgA molecule has been questioned. We investigated the impact of pre-analytical conditions on a CgA assay. MethodsSerum CgA concentrations were measured in blood samples collected from ten healthy subjects at three time points during three days with and without fasting. Samples were kept at 4°C and re-measured after 24 and 48h in order to test the stability of the measured epitopes. For establishment of a reference interval, serum samples were collected from 120 healthy individuals. ResultsSerum CgA concentrations did not vary between fasting and non-fasting individuals (p=0.74), nor between gender (p=0.66). The analytical imprecision was 4.3%, the within-subject variability was 11.9%, while the between-subject variability was as high as 50.2%. Serum CgA concentrations measured during the day did however not differ (p=0.30). Of importance, re-analysis at 4°C showed significant decay in the CgA concentrations after 24h (mean decrease 15.6%) and 48h (mean decrease 44%). The median CgA concentration in 120 healthy subjects was 41.2ng/mL with a reference interval of 30.3–94.4ng/mL (2.5–97.5 percentile). ConclusionsFasting does not influence CgA concentrations significantly, while sample stability is a major issue with the assay tested. The biological variation of CgA was defined and a reference interval was established.

FRI0592-HPR Relationship between energy expenditure and inflammatory markers linked to cardiovascular disease (CVD) in rheumatoid arthritis (RA)

BackgroundIt has recently come to light that the increased mortality risk in the RA population is related to increased CVD risk. The key feature explaining the increased CVD risk in...

Circulating MicroRNAs and Aerobic Fitness – The HUNT-Study

Aerobic fitness, measured as maximal oxygen uptake (VO2max), is a good indicator of cardiovascular health, and a strong predictor of cardiovascular mortality. Biomarkers associated with low VO2max may therefore represent potential early markers of future cardiovascular disease (CVD). The aim of this study was to assess whether circulating microRNAs (miRs) are associated with VO2max-level in healthy individuals. In a screening study, 720 miRs were measured in serum samples from healthy individuals (40–45 yrs) with high (n = 12) or low (n = 12) VO2max matched for gender, age and physical activity. Candiate miRs were validated in a second cohort of subjects with high (n = 38) or low (n = 38) VO2max. miR-210 and miR-222 were found to be higher in the low VO2max-group (p<0.05). In addition, miR-21 was increased in male participants with low VO2max (p<0.05). There were no correlations between traditional risk factors for CVD (blood pressure, cholesterol, smoking habit, or obesity) and miR-21, miR-210 and miR-222. DIANA-mirPath identified 611 potential gene-targets of miR-21, miR-210 and miR-222, and pathway analysis indicated alterations in several important signaling systems in subjects with low VO2max. Potential bias involve that blood was collected from non-fasting individuals, and that 8 performed exercise within 24 h before sampling. In conclusion, we found that miR-210, miR-21, and miR-222 were increased in healthy subjects with low VO2max. The lack of association between these three miRs, and other fitness related variables as well as traditional CVD risk factors, suggests that these miRs may have a potential as new independent biomarkers of fitness level and future CVD.

Using Nonfasting Lipids—Hemodilution or Convenience?

To the Editor: Langsted and Nordestgaard, of the Copenhagen General Population Study (CGPS),1 stated that “calculated LDL cholesterol concentrations do not change in response to normal food intake in individuals with and without diabetes after correction for hemodilution” (1). Using unpaired, nonrandomized samples, the authors estimated lipid differences between fasting and nonfasting individuals. Within-individual changes were not measured. Thus, to us, the authors’ conclusions about fasting/nonfasting “changes,” “increases,” or “decreases” were not appropriate. Notably, the maximum difference in the mean triglyceride concentration between fasting and nonfasting individuals with diabetes was 18 mg/dL (0.2 mmol/L). This difference apparently doubled to 35–44 mg/dL (0.4–0.5 mmol/L) (as graphically read) after adjusting for age and sex. We believe that a contrast of this magnitude, apparently arising from covariate adjustments, suggests considerable confounding between fasting and nonfasting individuals. Although Langsted and Nordestgaard did not mention the data in their report, the CGPS had previously reported significant differences between fasting and nonfasting individuals with respect to age, sex, smoking, and so forth (2), underscoring the possible confounding effect of self-selection by participants choosing fasting or nonfasting blood draws. Although the CGPS is a large-scale study, we do not believe that sample size per se affects confounding; it affects only statistical power. Albumin concentrations in the CGPS were significantly lower in nonfasting individuals than in fasting individuals (approximately 4%–5% lower at 1–2 h postprandially, as graphically read, P < 0.05), as were the concentrations of some lipids, e.g., LDL cholesterol (LDL-C) (approximately 9%–20% lower at 1–2 h postprandially, as graphically read, P < 0.01). After adjustment for albumin, the statistical significance in LDL-C differences disappeared. The CGPS used albumin as a proxy for hemodilution; that is, …

Whither the Lipid Profile: Feast, Famine, or No Free Lunch?

A lipid profile (LP)3 is used in clinical practice to assess risk of cardiovascular disease (CVD) and to guide therapy. The standard LP includes a direct measurement of plasma total cholesterol, triglyceride, and HDL cholesterol concentrations, and derived estimates of LDL cholesterol, non–HDL cholesterol, and lipid ratios (1). Expert guidelines recommend that accurate assessment of the LP requires a fast of 9 to 12 h (2). The principal reason is to diminish the biological variation in the plasma triglyceride concentration after ingestion of a fatty meal. Another reason is to compare plasma lipid levels with fasting data from healthy individuals. A fasting triglyceride concentration is also required for accurate estimation by the Friedewald formula of the cholesterol in LDL (3), the principal atherogenic lipoprotein. The established practice of fasting has been challenged by population studies that have shown that components of the LP, including triglycerides, do not change greatly when measured at different times during the day in nonfasting individuals (4). Compelling epidemiology data also show that nonfasting concentrations of triglycerides, LDL cholesterol, non–HDL cholesterol, and HDL cholesterol, as well as the lipid ratios, are significant predictors of cardiovascular (CV) events (5), possibly more than in the fasting state (6). Can these findings be extended to patients with type 2 diabetes, a group with a high prevalence of hypertriglyceridemia and perturbed cholesterol-rich lipoprotein metabolism (7)? Investigators from the Copenhagen General Population Study have assessed the plasma concentrations of lipids, lipoproteins, apolipoproteins, and albumin in 58 434 individuals, 2270 of whom had diabetes (8). Participants were asked the time since their last meal, and nonfasting blood samples were categorized accordingly. In individuals with and without diabetes, the plasma triglyceride concentration remained increased for up to 7 h after the last meal. A mean postprandial reduction of 0.6 mmol/L (23 …

Nonfasting Lipids, Lipoproteins, and Apolipoproteins in Individuals with and without Diabetes: 58 434 Individuals from the Copenhagen General Population Study

Whether lipid profiles should be collected from fasting or nonfasting individuals is controversial, particularly in the diabetic population. We examined the influence of normal food intake on lipid profiles in diabetic and nondiabetic individuals. We assessed plasma concentrations of lipids, lipoproteins, apolipoproteins, and albumin as a function of time since the last meal in 58 434 individuals (participation rate 45%) from the general population, 2270 of whom had diabetes mellitus. Similar patterns in the measured constituents were observed in the diabetic and nondiabetic populations. Triglycerides remained increased for 6-7 h in both populations after the last meal, whereas LDL cholesterol and albumin but not apolipoprotein B were reduced in both populations up to 5 h after normal food intake; after adjustment for hemodilution on the basis of albumin concentrations, the LDL cholesterol reductions were no longer present. Maximum observed mean differences from fasting concentrations in diabetic patients were -0.6 mmol/L, 0 mmol/L, 0.2 mmol/L, and 0.08 g/L (8 mg/dL) for LDL cholesterol, HDL cholesterol, triglycerides, and apolipoprotein B, respectively, and, correspondingly, -0.3 mmol/L, 0 mmol/L, 0.2 mmol/L, and 0.03 g/L (3 mg/dL) in individuals without diabetes. Triglycerides increased up to 0.2 mmol/L after normal food intake in individuals with and without diabetes, whereas the postprandial reductions in LDL cholesterol observed in both populations likely were caused by hemodilution due to fluid intake. No statistically significant differences in postprandial apolipoprotein B concentrations were found. These data may be useful for discussion during revisions of guidelines for lipid measurements in individuals with or without diabetes.

Water and salt balance in young male football players in training during the holy month of Ramadan

The aim of this study was to assess water and salt balance in young football players in training during Ramadan. Measurements were made in 92 young male football players before and during the month of Ramadan. Fifty-five participants were observing Ramadan fasting, while the other 37 participants were eating and drinking without restriction. In week 3 of Ramadan, water and salt balance measures were made during a training session of 60–70 min duration that was performed at an ambient temperature of 25–28°C and relative humidity of 50–53%. Body mass was recorded before and after training. Fluid intake was assessed in non-fasting players by weighing drink bottles before and after training, and the volume of any urine output was recorded. Sweat composition was estimated from absorbent patches applied to four skin sites for the duration of training. Mean sweat loss of players amounted to 1.41 litres (s = 0.36) in fasting players and 1.61 litres (s = 0.51) in non-fasting players (P = 0.038). Mean fluid intake during training in non-fasting players was 1.92 litres (s = 0.66). Sweat sodium concentration was 20 mmol · l−1 (s = 8) in fasting players and 17 mmol · l−1 (s = 7) in non-fasting players, and total sweat sodium loss during training was 0.67 g (s = 0.41) and 0.65 g (s = 0.37) [corresponding to a salt loss of 1.7 g (s = 1.1) and 1.7 g (s = 0.9)] respectively, with no difference between fasting and non-fasting players. Sweat sodium loss was not related to estimated dietary sodium intake (r = −0.07). These descriptive data show large individual variations in all measured parameters with relatively little difference in sweat parameters between fasting and non-fasting individuals.

Levels of apolipoprotein M are not associated with the risk of coronary heart disease in two independent case-control studies

Apolipoprotein M (apoM), a 25 kDa plasma protein belonging to the lipocalin protein family, is predominantly associated with HDL. Studies in mice have suggested apoM to be important for the formation of pre-beta-HDL and to increase cholesterol efflux from macrophage foam cells. Overexpression of human apoM in LDL receptor-deficient mice reduced the atherogenic effect of a cholesterol-rich diet. The aim of the present study was to investigate whether the apoM levels in man predict the risk for coronary heart disease (CHD). ApoM was measured in samples from two separate case-control studies. FINRISK '92 consisted of 255 individuals, of whom 80 developed CHD during follow-up and 175 were controls. The Copenhagen City Heart Study included 1,865 individuals, of whom 921 developed CHD during follow-up and 944 were controls. Correlation studies of apoM concentration with several analytes showed a marked positive correlation with HDL and total cholesterol as well as with apoA-I and apoB. There was no significant difference in mean apoM level between CHD and control subjects in either study. In conditional logistic regression analyses, apoM was not a predictor of CHD events, [odds ratio (95% CI) 0.97 (0.74-1.27) and 0.92 (0.84-1.02), respectively]. In conclusion, no association between apoM and CHD could be found in this study.