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PubMed2006

Glycemic load, glycemic index and carbohydrate intake in relation to risk of stomach cancer: a prospective study.

The glycemic effects of diets high in refined grains and starchy foods might increase stomach cancer risk by affecting circulating glucose, insulin and insulin-like growth factor-I levels. No prospective data on the role of high glycemic load and glycemic index diets on stomach cancer risk have been reported. We therefore prospectively investigated dietary glycemic load, overall glycemic index and carbohydrate intake in relation to the incidence of stomach cancer among 61,433 women in the population-based Swedish Mammography Cohort. Diet was assessed at baseline (1987-1990) and again in 1997. During 903,586 person-years of follow-up, a total of 156 incident cases of stomach cancer were ascertained. We observed no material associations of dietary glycemic load, overall glycemic index and total carbohydrate intake with the risk of stomach cancer. The multivariate hazard ratios for the highest versus the lowest quintile were 0.76 (95% CI = 0.46-1.25) for glycemic load, 0.77 (95% CI = 0.46-1.30) for overall glycemic index and 0.85 (95% CI = 0.50-1.43) for carbohydrate intake. The associations did not vary according to body mass index. Lack of information on Helicobacter pylori infection status did not allow stratification by this potential effect modifier. Findings from this population-based prospective cohort of middle-aged and elderly women did not provide evidence of a positive association between glycemic load, glycemic index and carbohydrate intake with risk of stomach cancer.

Aged↗

PubMedDate not supplied

The effect of religious, cultural and social identity on population genetic structure among Muslims in Pakistan.

Knowledge of historical demography and contemporary social stratification can be valuable in understanding disease patterns, including genetic disorders, especially in communities that have a high prevalence of endogamous and/or consanguineous marriages. This paper provides a background to the religious, historical and socio-cultural factors that have helped define the bounds of endogamy for Muslims in undivided India and more specifically since the creation of Pakistan. The preference for endogamous marriage is based on the clan-oriented nature of the society, which values and actively seeks similarities in social group identity based on several factors, including religious, sectarian, ethnic, and tribal/clan affiliation. Religious affiliation is itself multi-layered and includes religious considerations other than being Muslim, such as sectarian identity (e.g. Shia or Sunni, etc.) and religious orientation within the sect (Isnashari, Ismaili, Ahmedi, etc.). Both ethnic affiliation (e.g. Sindhi, Baloch, Punjabi, etc.) and membership of specific biraderis or zat/quoms are additional integral components of social identity. Within the bounds of endogamy defined by the above parameters, close consanguineous unions are preferential due to a congruence of key features of group- and individual-level background factors.

Consanguinity↗

PubMed2025

Proteomic signatures and predictive modeling of cadmium-associated anxiety in middle-aged and elderly populations: an environmental exposure association study.

BACKGROUND: Emerging evidence implicates environmental contaminants such as cadmium (Cd) as modifiable risk factors for anxiety. Despite growing recognition of heavy metal toxicity in neuropsychiatric disorders, the molecular mechanisms linking environmental exposure to anxiety pathogenesis remain poorly understood. METHODS: Based on the established cohort of individuals with cognitive impairment in cadmium-contaminated areas, this cross-sectional association study enrolled 50 middle-aged and elderly hospitalized patients from these regions, adhering to the STROBE guidelines. Blood concentrations of cadmium (Cd), lead (Pb), and mercury (Hg) were analyzed in relation to anxiety severity assessed via the Hamilton Anxiety Rating Scale (HAMA). Plasma proteomic profiling was performed using data-independent acquisition (DIA) quantitative technology with an LC-MS/MS platform (timsTOF Pro, Bruker Daltonics), systematically characterizing 2,531 proteins across all samples. Machine learning techniques, specifically XGBoost and LASSO, were employed to identify biomarkers that were subsequently validated through mediation analysis and animal experiments, allowing for the screening of key protein signatures. Finally, clinical variables were integrated to construct a comprehensive model, which was then thoroughly evaluated. RESULTS: Anxious individuals exhibited significantly higher blood Cd levels than controls (β = 0.50, 95% CI: 0.07-0.93, p < 0.01), with anxiety positively correlating with depression (r = 0.62, p = 0.003) and inversely with ApoE3 genotype prevalence. Proteomics identified 120 differentially expressed proteins in anxious patients, enriched in oxidative phosphorylation and neurodegenerative pathways. CCDC126 emerged as a cadmium-associated biomarker, validated in rat models exposed to Cd. Combining CCDC126, blood Cd, Pb, and hypertension, a clinical prediction model achieved robust discrimination (AUC = 0.80, validation cohort). CONCLUSIONS: This first integrative environmental-proteomic study highlights cadmium's synergistic role in anxiety pathophysiology and psychiatric comorbidity. The predictive model offers translatable potential for early risk stratification, while CCDC126 provides mechanistic insights for targeted interventions in populations exposed to environmental pollutants.

Cadmium↗

PubMed2005

Gastric and intestinal differentiation in Barrett's metaplasia and associated adenocarcinoma.

Intestinal metaplasia is a prerequisite criterion for the diagnosis of Barrett's metaplasia and the sole columnar esophageal lining associated with malignancy. It is recognized by the presence of goblet cells, but columnar non-goblet elements, producing gastric or intestinal proteins, are the prevalent cell population. The cellular heterogeneity of Barrett's metaplasia is well documented but the relationship between the distinct cell subtypes and neoplasia is unclear. Our aim was to clarify the relationship between the different metaplastic populations and malignancy in order to investigate putative markers for risk stratification of Barrett's patients. We studied 46 columnar-lined esophageal segments, 15 with associated adenocarcinoma. The presence of the gastric, MUC5AC and MUC6, and the intestinal, MUC2, proteins was evaluated in metaplastic (columnar and goblet) and neoplastic cells. In neoplasia MUC5AC and MUC6 were detected in 100% and 86.6% of the cases, respectively. In metaplasia there were no differences in MUC5AC and MUC6 immunoreactivity, between cases with and without associated neoplasia, except for goblet elements producing MUC6 that were exclusive of metaplasia adjacent to adenocarcinoma (P < 0.05). MUC2 was present in 86.6% of the neoplasia. In metaplasia it was restricted to Barrett's cases and was more frequent in areas with intestinal metaplasia. Columnar-lined esophagus without intestinal metaplasia did not express MUC2. Our study suggests a relationship between the metaplastic population with gastric phenotype and malignancy, and points to the involvement of columnar as well as goblet elements in tumorigenesis. The association between goblet cells aberrantly producing MUC6 and the presence of neoplasia suggests they may be useful for risk stratification.

Adenocarcinoma↗

PubMed1998

Cardiac troponin-I accurately predicts myocardial injury in renal failure.

BACKGROUND: Non-specific elevations of creatine kinase isoenzymes (CK-MB) and cardiac troponin-T may be seen in renal failure, confusing the diagnosis of myocardial infarction. Cardiac troponin-I (cTn-I) has been shown to be specific for myocardial damage in several disease states, but has not been prospectively evaluated in the setting of renal failure. METHODS: This prospective case series evaluated 56 patients with acute or chronic renal failure or end-stage renal disease to assess the sensitivity and specificity of cTn-I for detecting myocardial injury in this patient population. During a 6-month period, patients admitted with suspected myocardial injury by history, physical examination, and electrocardiography were evaluated. Cardiac troponin-I (cTn-I) measurements were assessed between 8 and 48 h after admission. Appropriate medical care and further cardiac testing (echocardiography, stress testing, or arteriography) was performed at the discretion of the primary physician. RESULTS: Myocardial injury was diagnosed in 18/56 (32%) patients by positive cTn-I levels, while only 7/56 (13%) patients had evidence of myocardial damage by CK-MB. Twenty-one of 56 (38%) patients had indeterminate CK-MB levels and 53% of these patients demonstrated myocardial ischaemia on follow-up testing. Sixteen patients had negative cardiac studies; all of these patients had negative cTn-I levels, while seven of these 16 (44%) patients had indeterminate CK-MB measurements. All of the patients with positive cTn-I levels had positive cardiac studies. Positive troponin levels were associated with increased in-hospital mortality. Sensitivity and specificity for CK-MB were 44 and 56% respectively, and 94 and 100% for cTn-I. CONCLUSION: These data support the use of cTn-I for diagnosing myocardial injury in patients with renal failure. Elevated cTn-I levels are associated with increased short-term mortality in renal failure patients. The accuracy of cTn-I could potentially limit unnecessary cardiac testing in renal failure patients, while the enhanced sensitivity contributes to risk stratification and aids in diagnosing true myocardial injury in this population susceptible to non-specific elevations in other muscle enzymes.

Acute Kidney Injury↗

PubMed2001

Distribution of cardiac geometric patterns on echocardiography in essential hypertension. Impact of two criteria of stratification.

PURPOSE: To evaluate 2 left ventricular mass index (LVMI) normality criteria for the prevalence of left ventricular geometric patterns in a hypertensive population ( HT ). METHODS: 544 essential hypertensive patients, were evaluated by echocardiography, and different left ventricular hypertrophy criteria were applied: 1 - classic : men - 134 g/m2 and women - 110 g/m2; 2- obtained from the 95th percentil of LVMI from a normotensive population (NT). RESULTS: The prevalence of 4 left ventricular geometric patterns, respectively for criteria 1 and 2, were: normal geometry - 47.7% and 39.3%; concentric remodelying - 25.4% and 14.3%; concentric hypertrophy - 18.4% and 27.7% and excentric hypertrophy - 8.8% and 16.7%, which confered abnormal geometry to 52.6% and 60.7% of hypertensive. The comparative analysis between NT and normal geometry hypertensive group according to criteria 1, detected significative stuctural differences,"( *p < 0.05):LVMI- 78.4 +/- 1.50 vs 85.9 +/-0.95 g/m2 *; posterior wall thickness -8.5 +/- 0.1 vs 8.9 +/- 0.05 mm*; left atrium - 33.3 +/- 0.41 vs 34.7 +/- 0.30 mm *. With criteria 2, significative structural differences between the 2 groups were not observed. CONCLUSION: The use of a reference population based criteria, increased the abnormal left ventricular geometry prevalence in hypertensive patients and seemed more appropriate for left ventricular hypertrophy detection and risk stratification.

Analysis of Variance↗

PubMed2006

Predicting hospitalization and mortality in end-stage renal disease (ESRD) patients using an Index of Coexisting Disease (ICED)-based risk stratification model.

We evaluated the use of an additive Index of Coexisting Diseases (ICED)-based stratification schema to determine subsequent hospitalization and mortality in a hemodialysis population. Patients from five commercial health plans were stratified into low-, medium-, and high-risk groups and followed for up to 1 year. Patients were reassessed and restratified at 90-day intervals and censored when disease management ceased. Outcome measures collected through selfreports and health plan records were captured in an active database. Survival to first hospitalization/ mortality was compared by Kaplan Meier curves, survivor function differences by the Wilcoxon test, and group comparisons by ANOVA and chi square. Population characteristics included mean age of 63.0, 57.7% male, and 58.8% diabetic. Mortality was 13.0% per patient year (standardized mortality ratio 0.43) and the hospitalization rate was 0.59 per patient year (standardized hospitalization ratio 0.24). Survival curves demonstrated differences in mortality and hospitalization between the patients in different initial risk categories (p < 0.01). Mean hospitalizations were 0.81 +/- 1.53 per patient year (high risk), 0.45 +/- 0.99 (medium risk), and 0.15 +/- 0.51 for the low-risk group (p < 0.001). Stratification was dynamic; 47.3% decreased and 4.7% increased risk level between the first and second assessment. These changes were associated with survival differences for initial low (p = 0.06) or medium patients (p < 0.01), and hospital-free survival for initial medium (p = 0.08) or high patients (p < 0.05). In conclusion, this ICED-based stratification schema predicted mortality and hospitalization for hemodialysis patients participating in our disease management program.

Analysis of Variance↗

PubMedDate not supplied

[Medical health care services for the population under the condition of social differentiation].

Monitoring of availability of medical care and drugs for the population has been carried out by interviewing more than 4000 residents of Russian cities. Stratification of respondents by the level of life showed that more than 70% respondents evaluate their level of life as below the medium. A social gradient was detected: direct relationship between population morbidity and conditions of life. Analysis of availability of paid medical services and drugs for population with different level of life showed differentiation of the population by the level of life and by ability to pay for medical services and drugs.

Adult↗

PubMed2006

Peripherality, income inequality, and life expectancy: revisiting the income inequality hypothesis.

BACKGROUND: Recent criticisms of the income inequality and health hypothesis have stressed the lack of consistent significant evidence for the stronger effects of income inequality among rich countries. Despite such criticisms, little attention has been devoted to the income-based criteria underlying the stratification of countries into rich/poor groups and whether trade patterns and world-system role provide an alternative means of stratifying groups. METHODS: To compare income-based and trade-based criteria, 107 countries were grouped into four typologies: (I) high/low income, (II) OECD membership/non-membership, (III) core/non-core, and (IV) non-periphery/periphery. Each typology was tested separately for significant differences in the effects of income inequality between groups. Separate group comparison tests and regression analyses were conducted for each typology using Rodgers (1979) specification of income, income inequality, and life expectancy. Interaction terms were introduced into Rodgers specification to test whether group classification moderated the effects of income inequality on health. RESULTS: Results show that the effects of income inequality are stronger in the periphery than non-periphery (IV) (-0.76 vs -0.23; P < 0.05). An incremental F-test confirmed significant differences in the coefficient subsets between the two groups (F(2,101) = 6.31; P < 0.01). CONCLUSIONS: Cross-national analyses of income inequality and population health have assumed (i) income differences between countries best capture global stratification and (ii) the negative effects of income inequality are stronger in high-income countries. However, present findings emphasize (i) the importance of measuring global stratification according to trading patterns and (ii) the strong, negative effects of income inequality on life expectancy among peripheral populations.

Commerce↗

PubMed2007

Redox-stratification controlled biofilm (ReSCoBi) for completely autotrophic nitrogen removal: the effect of co- versus counter-diffusion on reactor performance.

A multi-population biofilm model for completely autotrophic nitrogen removal was developed and implemented in the simulation program AQUASIM to corroborate the concept of a redox-stratification controlled biofilm (ReSCoBi). The model considers both counter- and co-diffusion biofilm geometries. In the counter-diffusion biofilm, oxygen is supplied through a gas-permeable membrane that supports the biofilm while ammonia (NH(4)(+)) is supplied from the bulk liquid. On the contrary, in the co-diffusion biofilm, both oxygen and NH(4)(+) are supplied from the bulk liquid. Results of the model revealed a clear stratification of microbial activities in both of the biofilms, the resulting chemical profiles, and the obvious effect of the relative surface loadings of oxygen and NH(4)(+) (J(O(2))/J(NH(4)(+))) on the reactor performances. Steady-state biofilm thickness had a significant but different effect on T-N removal for co- and counter-diffusion biofilms: the removal efficiency in the counter-diffusion biofilm geometry was superior to that in the co-diffusion counterpart, within the range of 450-1,400 microm; however, the efficiency deteriorated with a further increase in biofilm thickness, probably because of diffusion limitation of NH(4)(+). Under conditions of oxygen excess (J(O(2))/J(NH(4)(+)) > 3.98), almost all NH(4)(+) was consumed by aerobic ammonia oxidation in the co-diffusion biofilm, leading to poor performance, while in the counter-diffusion biofilm, T-N removal efficiency was maintained because of the physical location of anaerobic ammonium oxidizers near the bulk liquid. These results clearly reveal that counter-diffusion biofilms have a wider application range for autotrophic T-N removal than co-diffusion biofilms.

Ammonia↗

PubMed2004

The household registration system and social stratification in China: 1955-1996.

The Chinese household registration system (hukou), which divides the population into "agricultural" and "nonagricultural" sectors, may be the most important determinant of differential privileges in state socialist China, determining access to good jobs, education for one's children, housing, health care, and even the right to move to a city. Transforming one's hukou status from rural to urban is a central aspect of upward social mobility. Using data from a 1996 national probability sample, we show that education and membership in the Chinese Communist Party are the main determinants of such mobility.

Adult↗

PubMed1997

Factor VII and fibrinogen levels examined by age, sex, and other atherosclerotic risk factors in a Japanese population. The Jichi Medical School Cohort Study.

Factor VII coagulant activity (FVIIc) and fibrinogen (Fbg) levels have been investigated as cardiovascular risk factors. We studied these two factors with stratification for age, sex and blood pressure, and the relation with other atherosclerotic risk factors in a Japanese general population. The subjects were 3,139 Japanese (1,315 males and 1,824 females) aged 30 to 89 in 1992 and 1993. A linear increase with age was observed in the levels of Fbg in both men and women, but no differences were observed between men and women in each age group. A linear increase with age was also seen in the levels of FVIIc in women, but the levels of FVIIc in men were significantly higher for the age group 40-49 years than for any other age group. The levels of FVIIc in women were significantly higher than in men at age > or = 60 years. As concerning the effect of alcohol intake status, Fbg had a tendency to decrease with alcohol intake. Fbg and FVIIc levels were associated with an increase in smoking status in men, but no association was seen in women in either Fbg or FVIIc. FVIIc was positively correlated with age, body mass index, total cholesterol, triglycerides and fasting insulin level. Fbg was positively correlated with age, systolic blood pressure, diastolic blood pressure, total cholesterol, LDL-cholesterol and triglycerides in women, but Fbg had few positive correlations with risk factors in men. A comparison with previous Western studies showed that the Fbg levels of our Japanese population were lower than those of the Caucasians studied, but the present FVIIc levels were nearly the same level or slightly higher than theirs. The association of Fbg and FVIIc and with other cardiovascular risk factors in Japanese was similar to those observed in Caucasians.

Adult↗

PubMed2001

Assessment of subclinical atherosclerosis and cardiovascular risk.

Conventional cardiac risk factors do not fully explain the incidence of coronary artery disease and coronary events. Risk stratification and therapy based solely on these conventional risk factors may exclude a population who would otherwise benefit from lifestyle and risk factor modification. Recent efforts to improve our ability to recognize individuals and populations at increased risk of coronary events have focused on the noninvasive imaging of atherosclerosis, both in coronary and extracoronary arterial beds, or the identification of "non-traditional" serum markers. We review the complimentary role of these newer methods of risk stratification in the context of conventional risk factor evaluation.

Brachial Artery↗

PubMed2006

Predicting absolute risk of CIN3 during post-colposcopic follow-up: results from the ASCUS-LSIL Triage Study (ALTS).

OBJECTIVE: At present, clinical management of women referred to colposcopy but found to have <CIN2 remains unclear. Using data from the ASCUS-LSIL Triage Study (ALTS) to inform clinical management, we calculated the absolute risk for developing CIN3 within 2 years of referral to an enrollment colposcopy. STUDY DESIGN: Women included in the analyses: (1) were initially referred to ALTS with a community cytologic interpretation of atypical squamous cell of undetermined significance (ASCUS) or low-grade squamous intraepithelial lesions (LSIL); (2) had a colposcopic evaluation and biopsy, if indicated, resulting in a diagnosis <CIN2; and, therefore (3) were followed without treatment. Results from subsequent human papillomavirus (HPV) testing, liquid-based cytology interpretations, and a second colposcopic evaluation at least 6 months after and within 2 years of the first colposcopic evaluation were used to calculate absolute risks for CIN3. RESULTS: Women with HPV-negative test results were at low risk for CIN3 regardless of other test results. Among HPV-positive women, increasing absolute risks of CIN3 were observed with increasing cytology severity: 7% (normal), 11% (ASCUS and LSIL), and 45% (HSIL). The highest absolute risk for CIN3 (67%) was observed for HPV-positive women with HSIL and a colposcopic impression of high-grade/cancer on the second colposcopy. CONCLUSION: In the ALTS population, after the first colposcopic diagnosis of <CIN2, clear risk stratification for CIN3 outcomes was obtained among women with a subsequent HPV-positive test. Because absolute risk for histologic CIN3 outcomes was high for women with HPV positive tests, HSIL cytology, and a high-grade impression at second colposcopy, it is worth considering whether this combination of findings might warrant immediate excisional therapy in some circumstances.

Adult↗

PubMed2005

Association between psychiatric disorders and smoking stages among Latino adolescents.

OBJECTIVE: We examined the prevalence of smoking behaviors and their association with psychiatric disorders within a representative sample of youth from Puerto Rico. METHOD: A complex sampling design was used and analyses were conducted to account for the unequal selection probability, stratification and clustering. All analyses were weighted back to the population from which they were drawn. Psychiatric and substance use disorders were assessed using the parent and youth versions of the Diagnostic Interview Schedule for Children, Version 4.0 (DISC-IV). RESULTS: After controlling for other comorbidity, major depression and oppositional defiant disorder were significantly associated with nicotine dependence, rather than with lower levels of use. In contrast, conduct disorder was generally associated with lower levels of use rather than with nicotine dependence. As expected, the alcohol and drug use disorders demonstrated some of the strongest associations with individual smoking stages. CONCLUSIONS: By examining psychiatric correlates of smoking stages within an island-wide sample of adolescents, the present study highlights those disorders that may play a role in the development and/or persistence of smoking behavior in Puerto Rico and further clarifies the appropriate targets for smoking intervention conducted in community settings.

Adolescent↗

PubMed2004

Responsiveness to inhaled nitric oxide is a predictor for mid-term survival in adult patients with congenital heart defects and pulmonary arterial hypertension.

BACKGROUND: It was previously demonstrated that in adults with congenital heart disease and pulmonary arterial hypertension and/or the Eisenmenger syndrome, the pulmonary circulation remained responsive to inhaled nitric oxide (iNO). We wanted to evaluate whether the responsiveness to iNO was related to mid-term outcome in these patients. METHODS: In 21 consecutive patients, total pulmonary vascular resistance (TPR) was measured at baseline, after 5 min iNO (80 ppm), and after NO withdrawal. Patients were considered responders when TPR was reduced by at least 20% during NO inhalation or when TPR increased by more than 10% after NO withdrawal. Responders and non-responders were followed prospectively and the primary endpoint of the study was cardiopulmonary death, the secondary endpoint the combination of death, need for treatment with prostacyclin or heart-lung transplantation. Kaplan-Meier survival curves for both groups were plotted and compared using log rank testing. RESULTS: Ten patients were considered responders (four male, median age 25 years, Q1 19 and Q3 66 years), while 11 patients did not respond (two male, median age 27 years, Q1 18 and Q3 40 years). The median follow-up time of the total group was 5.0 years (Q1 3.2 and Q3 5.7 years). Four of the non-responders died a cardiovascular death; none of the responders died. The difference in survival between responders and non-responders was statistically significant. For the secondary endpoint, no significant differences were found between both groups. CONCLUSIONS: The responsiveness to inhaled NO in adult patients with pulmonary arterial hypertension and/or the Eisenmenger syndrome is related to mid-term outcome. These findings might be important for risk stratification and the choice of treatment in this specific patient population.

Administration, Inhalation↗

PubMed2006

The appropriate use of subpopulation corrections for differences in endogamous communities.

Zhivotovsky et al. [L.A. Zhivotovsky, S. Ahmed, W. Wang, A. Bittles, The forensic DNA implications of genetic differentiation between endogamous communities, Forensic Sci. Int. 119 (2001) 269-272] gave an estimate of 0.13 for the coancestry coefficient, theta in three co-resident Pakistani communities. Wang et al. [W. Wang, S.G. Sullivan, S. Ahmed, D. Chandler, L.A. Zhivotovsky, A.H. Bittles, A genome-based study of consanguinity in three co-resident endogamous Pakistan communities, Ann. Hum. Genet. 94 (2000) 41-49] explain that the sampling is from extended families but conclude that "the present findings show that differentiation resulting from genetic stratification by genetic relatedness can be very pronounced in specific populations and thus be important in the evaluation of forensic DNA evidence." In this paper we present simulation results that show that sampling from families will be expected to produce high values of theta regardless of the population value for theta. A theta value estimated in this way cannot be used in formulae suggested by NRC II [NRC II, National Research Council Committee on DNA Forensic Science, The Evaluation of Forensic DNA Evidence, National Academy Press, Washington, DC, 1996] (Eqs. (1) and (2)) to estimate the match probability for a DNA profile in a subpopulation. Whilst it may have some application to estimating the match probability from the pedigree itself there are superior methods for assigning match probabilities for relatives.

Asian People↗

PubMed2002

A polymorphism within intron 11 of the tau gene is not increased in frequency in patients with sporadic Alzheimer's disease, nor does it influence the extent of tau pathology in the brain.

There are numerous polymorphisms within the tau gene but these are in complete linkage disequilibrium and exist as two common extended haplotypes H1 and H2. We have investigated the frequency of these haplotypes in 83 cases of sporadic Alzheimer's disease (AD) using the +34 polymorphism in intron 11 of the tau gene as a marker of H1 and H2 haplotypes. The total amount of hyperphosphorylated tau protein (tau load), present as neurofibrillary tangles, neuropil threads or plaque neurites, was quantified in the frontal cortex of these patients and related to tau haplotype. We found no increase in H1H1 haplotype in this autopsy population of cases with AD compared to published control data. Stratification of cases for apolipoprotein E (APO E) genotype showed a slight, but not statistically significant, overrepresentation of epsilon 4 allele amongst bearers of H2 haplotype. There were no overall differences in tau load between haplotype groups though cases within each haplotype group bearing APO E epsilon 4 allele had a significantly higher tau load than those without epsilon 4 allele. Neither age at onset or duration of illness differed according to tau haplotype. We conclude that the frequency of tau gene H1 haplotype is not elevated in AD and possession of this has no impact upon the amount of tau pathology in AD.

Adult↗