Cohort study

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Gene-lifestyle interaction and type 2 diabetes: the EPIC interact case-cohort study.

Gene-lifestyle interaction and type 2 diabetes: the EPIC interact case-cohort study.

The design and methods of the InterAct case-cohort study have previously been described [9]. InterAct is a case-cohort study nested within the EPIC cohort, and the project involves 29 institutions in nine European countries. Ascertainment of incident T2D involved a review of the existing EPIC datasets at each centre using multiple sources of evidence including self-report, linkage to primary-care registers, secondary-care registers, medication use (drug registers), hospital admissions, and mortality data. Informa- tion from any follow-up visit or external evidence with a date later than the baseline visit was used. To increase the specificity of the case definition, we sought further evidence for all cases with information on incident T2D from fewer than two independent sources, including seeking information via individual medical records review in some centres. Cases in Denmark and Sweden were not ascertained by self-report, but identified via local and national diabetes and pharmaceutical registers, and hence all ascertained cases were considered to be verified. Follow-up was censored at the date of diagnosis, 31 December 2007, or the date of death, whichever occurred first. All ascertained cases with any evidence of diabetes at baseline were excluded. Prevalent diabetes was identified on the basis of baseline self-report of a history of diabetes, doctor-diagnosed diabetes, diabetes drug use, or evidence of diabetes after baseline with a date of diagnosis earlier than the baseline recruitment date.
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14 Lee mas

Acetylcholinesterase inhibitors and healing of hip fracture in Alzheimer's disease patients: a retrospective cohort study.

Acetylcholinesterase inhibitors and healing of hip fracture in Alzheimer's disease patients: a retrospective cohort study.

Objectives: This study was designed to assess effects of cholinergic stimulation using acetylcholinesterase inhibitors (AChEIs), a group of drugs that stimulate cholinergic receptors and are used to treat Alzheimer’s disease (AD), on healing of hip fractures. Methods: A retrospective cohort study was performed using 46-female AD patients, aged above 75 years, who sustained hip fractures. Study analyses included the first 6-months after hip fracture fixation procedure. Presence of AChEIs was used as pre- dictor variable. Other variables that could affect study outcomes: age, body mass index (BMI), mental state or type of hip fracture, were also included. Radiographic union at fracture site (Hammer index), bone quality (Singh index) and fracture healing com- plications were recorded as study outcomes. The collected data was analyzed by student’s-t, Mann-Whitney-U and chi-square tests. Results: No significant differences in age, BMI, mental state or type of hip fracture were observed between AChEIs-users and nonusers. However, AChEIs-users had better radiographic union at the fracture site (relative risk (RR),2.7; 95%confidence interval (CI),0.9-7.8), better bone quality (RR,2.0; 95%CI,1.2-3.3) and fewer healing complications (RR,0.8; 95%CI,0.7-1.0) than nonusers. Conclusion: In elderly female patients with AD, the use of AChEIs might be associated with an enhanced fracture healing and minimized complications.
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10 Lee mas

Combined impact of healthy lifestyle factors on colorectal cancer: a large European cohort study.

Combined impact of healthy lifestyle factors on colorectal cancer: a large European cohort study.

Given the high incidence and mortality rates [37], pre- vention strategies for reducing CRC are highly desired. In this context, there have been numerous studies ex- ploring individual lifestyle factors with regard to CRC risk [11,38-40]. However, studies on the combined effect of lifestyle factors on CRC risk have been more sparse [41-43]. In a study of 47,927 US men in the prospective Health Professionals Follow-up Cohort, after adjusting for age and family history of CRC comparing the risk score for the combined six modifiable colon cancer risk factors (obesity, physical inactivity, alcohol consumption, early adulthood cigarette smoking, red meat consump- tion and low intake of folic acid from supplements) at or above the approximate 20th, 10th, or 5th percentiles versus below, the PAR% increased from 39% to 48% and 55%, respectively [41]. In the Nurses’ Health Study among 83,767 US women, those who smoked, had a consist- ently high relative weight, low physical activity level, con- sumed red or processed meat on a daily basis, were never screened, and consumed low daily amounts of folate had almost a four-fold higher risk of colon cancer by the age of 70 years [43]. Another two studies provided data for European populations. A Danish Diet Cancer and Health cohort study [42] among 55,487 men and women, repor- ted 11% lower risk of CRC in people who adhered to five healthy lifestyle recommendations, including high phy- sical activity, low waist circumference, not smoking, low alcohol intake and a healthy diet (dietary fibre, energy per- centage from fat, red and processed meat, and fruits and vegetables). However, the study included participants
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15 Lee mas

Dietary magnesium intake and risk of hypertension in a Mexican adult population: A cohort study

Dietary magnesium intake and risk of hypertension in a Mexican adult population: A cohort study

Other study limitations relate to possible confounding of data. First, the participants might have changed their diets after developing disease, leading to a conservative estimate of the relationship between magnesium and blood pressure. However, this is unlikely since the model that excluded participants who had histories hypertension or dyslipidemia generated null associations similar to other models. Second, we did not separately compare the effects of dietary magnesium and supplementary magne- sium, but since subjects’ intake of magnesium from supplements was minor compared with dietary intake, this was not likely to have influenced the results. Finally, while we adjusted for potential confounding factors, the possibility of residual or unmeasured confounds still remains. In addition, the participants in this cohort study are adults from a specific segment of the Mexican popula- tion: working class, seemingly healthy individuals. While they cannot be considered representative of the Mexican adult population as a whole, they may be considered representative of middle- to low-income adults residing in the urban areas of central Mexico.
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8 Lee mas

Prediction of prolonged mechanical ventilation for intensive care unit patients: A cohort study

Prediction of prolonged mechanical ventilation for intensive care unit patients: A cohort study

Methods: This is cohort study made at a general intensive care unit. Patients who required at least 48 hours of mechanical ventilation were included. Data on the clinical and physiologic features were collected for every intubated patient on the third day. Uni- and multivariate statistical analyses were conducted to determine the variables associated with extubation. Results: 163 (62%) were male, and the median age was 59±17 years. Almost one-third (36%) of patients required mechanical ventilation longer than 7 days. The variables strongly associa- ted with prolonged mechanical ventilation were: age (HR 0.97 (95% CI 0.96-0.99); diagnosis of surgical emergency in a pa- tient with a medical condition (HR 3.68 (95% CI 1.62-8.35), diagnosis of surgical condition-non emergency (HR 8.17 (95% CI 2.12-31.3); diagnosis of non-surgical-medical condition (HR 5.26 (95% CI 1.85-14.9); APACHE II (HR 0.91 (95% CI 0.85-0.97) and SAPS II score (HR 1.04 (95% CI 1.00-1.09) The area under ROC curve used for prediction was 0.52. 16% of patients were extubated after day 8 of intubation.
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5 Lee mas

The Effect of Tapered Abutments on Marginal Bone Level: A Retrospective Cohort Study

The Effect of Tapered Abutments on Marginal Bone Level: A Retrospective Cohort Study

The present cohort study has different limitations that should be taken into account. First, the study design was retrospective, and a single-cohort, thus reducing the meaningfulness and external validity of the results. The implant was chosen as the first cluster of analysis which does not guarantee independence between implants, however the mixed effect model applied took the random effect posed by patients into account, not revealing any significant discrepancy with the fixed effect model. It must be remarked that the radiographic artifact of a stable first bone-to-implant contact does not necessarily imply histologic osseo-integration. However, the imaging accuracy of digital radiography is high with a precision of 0.1 mm or less. Still, the clinical relevance of such small entities is questionable and difficult to repeat among different operators [29]. Furthermore, the present study is a single cohort study without an internal control group.
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10 Lee mas

Follow up of women with inadequate Pap smears: a prospective cohort study

Follow up of women with inadequate Pap smears: a prospective cohort study

DESIGN AND SETTING: Prospective cohort study at primary healthcare clinics in Santiago, Chile. METHODS: The population was taken from the “Cito-Expert” database of 2010. The data were then or- ganized according to the cytological and histological follow-up results of 2,547 women with inadequate cervical cytological reports over the 12-month period. The samples were assigned to groups based on the cause of inadequacy (smears with endocervical cells alone; insufficient, hemorrhagic, inflammatory or poorly fixed samples; insufficient and hemorrhagic samples; or insufficient and inflammatory specimens). The data were analyzed using the “conditional probability tree diagram” and descriptive statistics. RESULT: Half of the women (n = 1,285) met the requirements of the Ministry of Health for repeating these inadequate smears, and 1,104 of these women had normal cytological results (85.9%). The detection rate for cervical lesions according to group ranged from 0% (smears with endocervical cells alone or insuf- ficient and hemorrhagic specimens) to 4.1% (poor fixation).
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8 Lee mas

Utility and Safety of Tolvaptan in Cirrhotic Patients with Hyponatremia: a Prospective Cohort Study

Utility and Safety of Tolvaptan in Cirrhotic Patients with Hyponatremia: a Prospective Cohort Study

Introduction and aim. Hyponatremia is common in patients with decompensated cirrhosis and is as- sociated with increased mortality. Tolvaptan, a vasopressor V2 receptor antagonist, can increase free wa- ter excretion, but its efficacy and safety in cirrhotic patients remain unclear. Material and methods. We studied the usage and safety of tolvaptan in cirrhotic patients in a real-life, non-randomized, multi- center prospective cohort study. Forty-nine cirrhotic patients with hyponatremia were treated with tolvaptan 15 mg daily, and 48 patients not treated with tolvaptan in the same period served as controls. Improvement in serum sodium level was defined as an increase in serum sodium from < 125 to ≥ 125 mmol/L or from 125-134 to ≥ 135 mmol/L on day 7. Results. Twenty-three (47%) patients in the tolvaptan group and 17 (35%) in the control group had normal serum sodium on day 7 (p = 0.25). Serum sodium improved in 30 (61%) patients in the tolvaptan group and 17 (35%) patients in the control group (p = 0.011). Adverse events occurred in 46-47% of patients in both groups, and tolvaptan was not associ- ated with worsened liver function. No patient with normal serum sodium on day 7 died within 30 days of treatment, whereas 16% of those with persistent hyponatremia died (p = 0.0019). Conclusion. In conclusion, short-term tolvaptan treatment is safe and can improve serum sodium level in cirrhotic pa- tients with hyponatremia. Normalization of serum sodium level is associated with better survival.
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10 Lee mas

Clinical Impact of Portal Vein Thrombosis Prior to Liver Transplantation: A Retrospective Cohort Study

Clinical Impact of Portal Vein Thrombosis Prior to Liver Transplantation: A Retrospective Cohort Study

found in Analysis One (PVT in 14% of patients), we decid- ed to add data from another LT center to enhance statisti- cal validity of PVT patients specific analysis, but as this was incomplete for the purpose of Analysis One, we ob- tained such additional data only for Analysis Two, thus minimizing selection bias. Therefore, Analysis Two con- sisted of a multicenter cohort study of cirrhotic patients with PVT diagnosed previously to or at LT from the Uni- versity of Alberta Hospital and London Health Sciences Center (London, Ontario, Canada) during the same time period (January 1, 2002 and June 30, 2012) (Figure 1). For PVT patients, the following data was additionally collect- ed: PVT characteristics, any other hypercoaguable state (e.g. myeloproliferative disease, factor V Leiden deficien- cy, S or C protein deficiency, antithrombin deficiency), pre- and post-LT antithrombotic therapy, portal vein sur- gical approach, red-blood cells transfusions during trans- plant, and portal vein reocclusion after LT.
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11 Lee mas

Breast bud detection : a validation study in the Chilean growth obesity cohort study

Breast bud detection : a validation study in the Chilean growth obesity cohort study

Background: Early puberty onset has been related to future chronic disease; however breast bud assessment in large scale population studies is difficult because it requires trained personnel. Thus our aim is to assess the validity of self and maternal breast bud detection, considering girl ’ s body mass index (BMI) and maternal education. Methods: In 2010, 481 girls (mean age = 7.8) from the Growth and Obesity Chilean Cohort Study were evaluated by a nutritionist trained in breast bud detection. In addition, the girl(n = 481) and her mother(n = 341) classified the girl ’ s breast development after viewing photographs of Tanner stages. Concordance between diagnostics was estimated (kappa, Spearman correlation) considering girls ’ BMI and mother ’ s educational level.
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7 Lee mas

Long-term outcome of patients after a single interruption of antiretroviral therapy: a cohort study.

Long-term outcome of patients after a single interruption of antiretroviral therapy: a cohort study.

The interruptions analysed in our study occurred in a specific context in the history of HAART: the previous hypothesis that HIV infection could be cured was proved false; the late side effects of some drugs were emerging; and the alternative regimens were scarce. Ob- viously, the context today is different. However, based on the long term follow-up of our series, and since still most present regimens are based on 2 NRTI plus a NNRTI or PI, we think our data may be useful in the decision-making process and advice to patients when an interruption of HAART has happened or is being dis- cussed. The variables associated to a shorter time for restarting HAART (higher age, CD4+ nadir <250 cells/ μL, and a higher VL during the interruption) are sound and in agreement with previous investigations [13-16],
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8 Lee mas

Light and the outcome of the critically ill: an observational cohort study

Light and the outcome of the critically ill: an observational cohort study

that determines the best-fitting polynomial-regression function [19]. This method makes no underlying assump- tions about the relationship between photoperiod or insolation and outcome and thereby averts the potential bias involved in pre-specifying the functional form. By separating the period before ICU admission from the period during ICU admission, we also accounted for potential immortal time bias, a situation that refers to cohort follow-up time in a time-to-event analysis like our study; owing to the exposure definition, the outcome under study could not occur during the follow-up time [20]. Statistical analyses were performed with Stata 11.2 (StataCorp LP, College Station, TX, USA). A P value of less than 0.05 was considered significant.
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8 Lee mas

TítuloTime loss injuries in karate: a prospective cohort study of 4 consecutive world karate championships

TítuloTime loss injuries in karate: a prospective cohort study of 4 consecutive world karate championships

There are limitations to the current study. First, injuries may be underreported, as it is possible that some injured athletes did not seek medical attention or care or that refer- ees may have failed to call on the doctor when an athlete was injured. However, the degree of underreporting of inju- ries is likely to be small because the scoring system stipu- lates that valid techniques should not cause harm or injury to the opponent, which means that athletes have an incen- tive to disclose all injuries, and referees are instructed to call on the doctor when a potentially injurious incident occurs. Second, the severity of injuries in terms of the actual number of days lost to participation was not mea- sured in this study. However, in large international cham- pionships, it is not feasible to follow up with individual athletes who return to their respective countries after the conclusion of the tournament. Third, because we did not know the age of each athlete competing at the champion- ships, we were not able to investigate whether the injury risk varied by age. We recommend future studies to inves- tigate the potential effect of age.
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6 Lee mas

Clinical management of the first ASCUS report in Chile  Prospective single cohort study

Clinical management of the first ASCUS report in Chile Prospective single cohort study

At the end of the follow-up period, the cohort of 446 female with a first ASCUS report achieved the following results (exclud- ing the 83 women who had been lost from the follow-up): nega- tive for neoplasia (n = 313) (86.2%); and negative for neoplasia plus presence of HPV (n = 7) (1.9%). Neoplastic lesions of vari- ous degrees were presented by 43 patients (11.9%). Cytological- colposcopic-histological diagnostic procedures were used to confirm normal results, and histological diagnostic procedures were used to confirm lesions (Figure 4).

8 Lee mas

Observational Cohort Study of Hepatic Encephalopathy After Transjugular Intrahepatic Portosystemic Shunt (TIPS)

Observational Cohort Study of Hepatic Encephalopathy After Transjugular Intrahepatic Portosystemic Shunt (TIPS)

In terms of the study limitations, the study was retro- spective, which brings limitations such as inability to con- trol for confounding factors, some missing data and lost to follow up. The TIPS is highly specialized procedure and therefore the centre covered a large geographic area mak- ing follow up attendance difficult for some patients from distant cities, leading to slightly higher lost to follow up.

9 Lee mas

Reappraisal of the outcome of healthcare-associated and community-acquired bacteramia: a prospective cohort study.

Reappraisal of the outcome of healthcare-associated and community-acquired bacteramia: a prospective cohort study.

CA and 3 HCA episodes from the initial cohort). The sample size was similar to that in previous studies [4,8,9], which would provide a β error of 0.71 for a 10% crude difference in mortality between HCA and CA epi- sodes. The general epidemiological data for HCA and CA episodes have been reported previously [10], being the main significant differences that the CA presented more often an urinary source of the BSI (31% vs 21%, p = 0,04) and were more often caused by S. pneumoniae (18% vs 6%, p = 0,001); the HCA BSIs were more often developed by neutropenic patients (1% vs 7%, p = 0,02), more often related to a previous antimicrobial use (18% vs 32%, p = 0,003), the source was more often un- known (15% vs 23%, p = 0,05) or secondary to a catheter device (0% vs 12%, p < 0,001) and was more often caused by P. aeruginosa (1% vs 9%, p = 0,01). As previously reported, differences in mortality between HCA and CA BSI were not statistically significant, either at day 14 (18% vs 15%, p = 0.47) or at day 30 (21% vs 19%, p = 0.67) [10].
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10 Lee mas

Relative adrenal insufficiency and hemodynamic status in cardiopulmonary bypass surgery patients. A prospective cohort study

Relative adrenal insufficiency and hemodynamic status in cardiopulmonary bypass surgery patients. A prospective cohort study

The only risk factor associated with RAI in our study was the use of etomidate after adjusting for confounder variables, including a control with propensity score. Adrenal suppression in humans with induction doses of etomidate has been shown in several studies,[6,16-18] suggesting suppression persisting for at least 24 h follow- ing cardiac surgery[19]. Etomidate temporarily impairs cortisol synthesis[6]. This drug has a very important role in the safe induction of unstable patients, but may impair haemodynamic status through cortisol inhibition. Nota- bly, RAI and lower cortisol levels were related to
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7 Lee mas

Results of Liver Transplantation for Hepatocellular Carcinoma in a Multicenter Latin American Cohort Study

Results of Liver Transplantation for Hepatocellular Carcinoma in a Multicenter Latin American Cohort Study

From a total of 2,761 consecutive adult LT patients in 17 different centers during the study period previously de- scribed, 435 patients with cHCC and 92 with iHCC were included (Figure 1). Percentage of patients contributed by participating LT centers per country was as follows: 2 from Brazil (n = 221, 41.9%), 5 transplant programs from Argentina (n = 136, 25.8%), 2 from Colombia (n = 77, 14.6%), 4 from Chile (n = 55, 10.4%), 2 from Mexico (n = 13, 2.5%), and 1 from Peru (n = 14, 2.7%) and Uruguay (n = 11, 2.1%). Patients within MC from Argentina, Brazil, Uruguay, Peru and Chile could receive additional MELD points while on the waiting list. Table 1 shows a descrip- tion of the overall cohort. Subsequent analysis was consid- ered excluding incidental HCC.
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12 Lee mas

Human Papillomavirus infection in men residing in Brazil, Mexico, and the USA

Human Papillomavirus infection in men residing in Brazil, Mexico, and the USA

Men were recruited from three different population sources –general population, universities, and organized health care systems (Mexico only)– to increase access to men with a broad range of ages, sexual behaviors, and HPV risk. In Brazil, men were recruited from the gen- eral population at a facility for urogenital care (Centro de Referencia e Tratamento de Doencas Sexualmente Transmissiveis e AIDS) and through general media advertising. Men presenting for non-STI related condi- tions were enrolled in the present study. In addition, the spouses and partners of women participating in a large cohort study of the natural history of HPV infection and risk of cervical neoplasia conducted in Sao Paulo since 1993 were also recruited. At the Cuernavaca, Mexico site, the underlying population was employees and beneficiaries of the Instituto Mexicano de Seguro Social (IMSS), factory employees, and officials of the Mexican army that are permanently assigned to this geographic area. In the U.S., the underlying population was from the University of South Florida and the greater Tampa metropolitan area. Flyers and posters were distributed throughout the campus and community, and we admin- istered monthly educational presentations. In addition, men from the broader Tampa Bay, FL, community were recruited through the mail and media using brochures and flyers as well as advertisements in local and uni- versity papers.
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11 Lee mas

Study protocol for the Maule Cohort (MAUCO) of chronic diseases, Chile 2014 2024

Study protocol for the Maule Cohort (MAUCO) of chronic diseases, Chile 2014 2024

MAUCO will provide high quality data and biological samples that will be a resource for national and inter- national research. Prevalence and dynamics of risk factors for CDs and their biomarkers will be measured in a unique epidemiological setting thus far not consid- ered in the large cohorts of developed countries. This cohort is similar in aims to European cohorts, such as each of the German National Cohorts [27] and LifeLines Cohort Study & Biobank [28]. MAUCO is exploring a broad range of exposures from genetics to environmen- tal exposures and their impact on health status, quality of life, aging and cognitive performance. After an 8-year embargo to complete the baseline measurements, data and samples will be available for the scientific community. MAUCO will permit assessing the effect of common risk factors and establishing the reference values in this population, providing key data for the design of interven- tions suitable for this group. Furthermore, MAUCO will provide the strategies, methods and tools to conduct this type of study in other populations with diverse epidemio- logical settings.
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7 Lee mas

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