Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Cohort Analysis”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources
PubMed2002

Impact of HIV seropositivity on graft and patient survival after cadaveric renal transplantation in the United States in the pre highly active antiretroviral therapy (HAART) era: an historical cohort analysis of the United States Renal Data System.

BACKGROUND: National statistics are presented for patient survival and graft survival in patients seropositive for the human immunodeficiency virus (HIV+) at the time of renal transplantation in the era prior to highly active antiretroviral therapy (HAART). METHODS: Historical cohort analysis of 63, 210 cadaveric solitary renal transplant recipients with valid HIV serology entries in the United States Renal Data System (USRDS) from 1 January 1987 to 30 June 1997. The medical evidence form was also used for additional variables but, because of fewer available values, was analyzed in a separate model. Outcomes were patient characteristics and survival associated with HIV+ status. RESULTS: Thirty-two patients (0.05%) in the study period were HIV+ at transplant. HIV+ patients were comparable to the national renal transplant population in terms of gender and ethnic distribution but were younger and had younger donors and better HLA matching than the USRDS population. Patient and graft three-year survival were significantly reduced in HIV+ recipients (53% graft, 83% patient survival) relative to the USRDS population (73% and 88%, respectively). In multivariate analysis, HIV+ status was independently associated with patient mortality and decreased graft survival in recipients of cadaveric kidney transplants. CONCLUSIONS: This analysis was retrospective and may underestimate the number of HIV+ patients transplanted in the United States. Although the clinical details of patient selection for transplant were unknown, these results show HIV+ patients can have successful outcomes after cadaveric renal transplantation, although outcomes are significantly different from HIV- recipients.

Adult↗
PubMed1997

Individual patient cohort analysis of the efficacy of hypertonic saline/dextran in patients with traumatic brain injury and hypotension.

BACKGROUND: Resuscitation with hypertonic saline/dextran (HSD) has been suggested to be efficacious in patients who have traumatic brain injury and are hypotensive. We undertook a cohort analysis of individual patient data from previous prospective randomized double-blinded trials to evaluate improvements in survival at 24 hours and discharge after initial treatment with HSD in patients who had traumatic brain injury (head region Abbreviated Injury Score > or = 4) and hypotension (systolic blood pressure < or = 90 mm Hg). METHODS: All variables and end points were defined before initiation of data handling. Investigators were blind as to the treatment. Case report forms were received from six studies. Of these, 223 patients met the inclusion for traumatic brain injury. Comparisons between HSD and standard of care were made using stratified analysis and logistic regression to assess efficacy, confounding, and interaction. Potential confounding variables of pre-fluid treatment, Glasgow Coma Scale score (3-8 vs. 9-15), injury type, and systolic blood pressure can be considered a priori factors that were known before randomization. Effects of the various trials was also considered. RESULTS: Treatment with HSD resulted in a survival until discharge of 37.9% (39 of 103) compared with 26.9% (32 of 119) with standard of care (p = 0.080). Using logistic regression, adjusting for trial and potential confounding variables, the treatment effect can be summarized by the odds ratio of 2.12 (p = 0.048) for survival until discharge. CONCLUSIONS: Patients who have traumatic brain injuries in the presence of hypotension and receive HSD are about twice as likely to survive as those who receive standard of care.

Abbreviated Injury Scale↗
PubMed2006

Cohort analysis of two multidisciplined adherence intervention programmes for patients on antiretroviral therapy.

The aim was to analyse data from two randomized controlled trials (RCTs) to determine if an adherence intervention programme for antiretroviral therapy (ART) resulted in a reduction in viral load. A cohort analysis of pre- and post-intervention viral loads and CD4 counts using paired analysis was undertaken on participants who received the intervention programme. Analysis was also undertaken on a control group. The intervention participants had an increase in mean CD4 count (450-478, P = 0.26), and a decline in log viral load (2.48-2.36, P = 0.056). The control group had a decline in mean CD4 counts (596-570, P = 0.53), and an increase in log viral load (2.09-2.11, P = 0.78). The use of an adherence intervention programme is associated with a decrease in mean viral load, which is in contrast to the control group that demonstrated an increase in viral load over time.

Antiretroviral Therapy, Highly Active↗
PubMed2006

Improved outcome of adult blunt splenic injury: a cohort analysis.

BACKGROUND: The purpose of this study was to review our 15-year experience in the treatment of blunt splenic injury in adults. Our hypothesis was that the implementation of a change in practice, with stress on splenic preservation and splenic artery embolization for the management of splenic injury, would result in improved splenic salvage rates without negatively affecting mortality rates. METHODS: A retrospective cohort analysis was performed on all consecutive adults with blunt splenic injury who were admitted to a Level One Trauma Center. The cohorts were defined by 2 separate 7.5-year periods (1991-1998 and 1998-2005). RESULTS: Six hundred twenty-five patients with blunt splenic trauma were identified; 403 patients who were treated from 1998 to 2005 were compared with 222 patients whose cases had been reviewed previously (1991 to 1998). The present cohort differed in age (35 vs 40 years; P < .001) and injury severity score (27 vs 21; P < .0001). Nonoperative treatment was implemented in 136 patients (61%) in the initial cohort and 344 patients (85%) in the present cohort. The frequency of splenic artery embolization increased from 2.7% to 22.6% (P < .001). The success of nonoperative management increased from 77% to 96% (P < .001); the splenic salvage rate for all patients improved from 57% to 88% (P < .0001). Hospital mortality rates decreased from 12% to 6% (P < .001), and the mean hospital length of stay decreased from 15 to 9 days (P < .001). CONCLUSION: These results demonstrate that the success of nonoperative management and the splenic preservation for blunt injury has improved over time. This improvement correlated with a greater use of splenic artery embolization.

Adolescent↗
PubMed2006

Results of cohort analysis by category of tuberculosis retreatment cases in Morocco from 1996 to 2003.

OBJECTIVE: To analyse treatment outcomes by subcategory of tuberculosis (TB) retreatment cases. METHODS: All TB patients treated with the Category II regimen from 1996 to 2003 in Morocco were enrolled in this retrospective study. For each cohort, the retreatment outcome data were analysed as a whole and by the following sub-categories: 1) cases who relapsed after one course of anti-tuberculosis treatment; 2) cases who failed the Category I regimen; and 3) cases who interrupted one course of anti-tuberculosis treatment. RESULTS: The study population included 14 635 retreatment patients, among whom 81.7% were TB relapse cases, 5.2% had failed the Category I regimen and 13.1% were defaulters. The average treatment success rates were respectively 74.8% (range 71.8-76.6), 58.0% (range 52.4-74.0) and 51.4% (range 46.4-55.6) among relapse, failure and default cases. Failure and default rates were significantly higher (P < 0.001) among patients who failed Category I treatment and among those who defaulted, respectively. CONCLUSIONS: TB cases who fail the Category I regimen should systematically receive drug susceptibility testing, while defaulters should be given support to improve treatment adherence. Stratified cohort analysis by subcategory of retreatment has been shown to be useful for evaluating the performance of TB control programmes.

Antitubercular Agents↗
PubMed2004

Mortality trends of multiple sclerosis in Spain, 1951-1997: an age-period-cohort analysis.

Trends of multiple sclerosis mortality in Spain from 1951 to 1997 are examined. Age-adjusted mortality strongly decreased from 3.08 per 100,000 women in 1951-1967 to 0.59 in 1968-1980 (similar figures were obtained for men). This decrease seems to be due to an artifact produced by changes in codification of causes of death. An age-period-cohort analysis, limited to the period 1968-1997, showed that the mortality trend in Spain cannot be fully explained by year of death (period effect), but that a cohort (year of birth) effect is also necessary. An increase in mortality related with the cohort of birth was detected: people born after 1953 had double the risk of those born between 1938 and 1947, and four times the risk of those born between 1923 and 1932. Regarding the period effect, there is a decrease in mortality, probably due to improvements in life expectancy of multiple sclerosis patients.

Adult↗
PubMed1985

Mortality from prostate cancer in Italy: 1950-1979. Cross-sectional rates and cohort analysis.

This paper studies prostate cancer mortality in Italy from 1950-1979 to evaluate its importance in relation to total cancers, examine the time trend for forecasting future mortality trends, and makes an attempt to interpretate mortality by analyzing demographic and risk factors. In the Authors' opinion findings from cross-sectional rates, cohort analysis and Devesa-Schneiderman method, indicate that in Italy even if the age-adjusted mortality rate has nearly doubled over the period, as in many other countries, mortality can be expected to remain constant or decrease in the future, since the data to hand show a decreasing trend in some age cohorts.

Age Factors↗
PubMed1996

Incidence of multiple sclerosis in Møre and Romsdal, Norway from 1950 to 1991. An age-period-cohort analysis.

We have examined the time trends in multiple sclerosis incidence over the past four decades from 1950 to 1991 in Møre and Romsdal County, Norway. Incidence rates by year of birth, year of onset and year of diagnosis according to sex, age and clinical course were studied. All patients with multiple sclerosis diagnosed by August 1992 were included, giving a total of 419 patients (171 men, 248 women) with onset of multiple sclerosis in the period 1950-91. Mean age at onset was 33.2 years, and mean age at diagnosis was 39.2 years. The incidence rate by year of onset increased from 2.87 per 100 000 in the period 1950-54 (men 3.06, women 2.67) to 5.57 per 100 000 in 1985-91 (men 3.75, women 7.94) (P<0.001). The incidence was particularly high in the period from 1975 to 1985. Major period- or cohort-effects in incidence, apart from the general increasing trend, could not be identified by an age-period-cohort analysis.

Adolescent↗
PubMed1987

Age-period-cohort analysis of secular trends in onset of major depression: findings in siblings of patients with major affective disorder.

Analyses of data from the NIMH-CRB Collaborative Depression Study on age at onset of Major Depressive Disorder (MDD) in 1144 directly interviewed siblings of patients with major affective disorder show a strong secular trend toward increased lifetime risk and earlier onset in successive cohorts of birth since 1930. The proportionate increases in the instantaneous probabilities (hazard) of onset of MDD for each one year difference in year of birth were 5% for brothers and 7% for sisters. Age-period-cohort analysis suggests a powerful period effect may be responsible for this secular trend in rates of MDD, with rates of onset for siblings between 15 and 50 years of age doubling between the 1960s and 1970s. Possible artifacts are investigated.

Adolescent↗
PubMed1998

Standardized tuberculosis treatment outcome monitoring in Europe. Recommendations of a Working Group of the World Health Organization (WHO) and the European Region of the International Union Against Tuberculosis and Lung Disease (IUATLD) for uniform reporting by cohort analysis of treatment outcome in tuberculosis patients.

Consensus-based recommendations have been developed by a Working Group of the World Health Organisation (WHO) and the International Union Against Tuberculosis and Lung Disease (IUATLD) on uniform reporting of tuberculosis (TB) treatment outcome data in countries in Europe. The main purpose of treatment monitoring is to find out how many of the potential infectious TB patients notified were declared cured at the end of treatment. Following the uniform case definitions as defined in 1996, emphasis is placed on cohort analysis of definite cases of pulmonary TB. The Working Group recommends using a minimal set of six mutually exclusive categories of treatment outcome: cure, treatment completed, failure, death, treatment interrupted, and transfer out. More detailed subsets may be chosen. Treatment outcome is expressed as a percentage of the total number of cases notified. Analysis should be separate for new and retreatment cases. Treatment outcome data have to be collected at the local level and passed on to regional and national authorities on an ongoing basis. Evaluation of treatment results becomes, preferably, an inbuilt component of national monitoring of programme performance. Because of the long duration of treatment, it is recommended that analysis is carried out in the first quarter of the calendar year that follows a full year after the last patient was enrolled. Feedback is essential. Treatment outcome results should become an inseparable part of the annual report on tuberculosis.

Cohort Studies↗
PubMed2003

The risk of venous thromboembolism in women prescribed cyproterone acetate in combination with ethinyl estradiol: a nested cohort analysis and case-control study.

BACKGROUND: Cyproterone acetate combined with ethinyl estradiol (CPA/EE) is licensed in the UK for the treatment of women with acne and hirsutism and is also a treatment option for polycystic ovary syndrome (PCOS). Previous studies have demonstrated an increased risk of venous thromboembolism (VTE) associated with CPA/EE compared with conventional combined oral contraceptives (COCs). We believe the results of those studies may have been affected by residual confounding. METHODS: Using the General Practice Research Database we conducted a cohort analysis and case-control study nested within a population of women aged between 15 and 39 years with acne, hirsutism or PCOS to estimate the risk of VTE associated with CPA/EE. RESULTS: The age-adjusted incidence rate ratio for CPA/EE versus conventional COCs was 2.20 [95% confidence interval (CI) 1.35-3.58]. Using as the reference group women who were not using oral contraception, had no recent pregnancy or menopausal symptoms, the case-control analysis gave an adjusted odds ratio (OR(adj)) of 7.44 (95% CI 3.67-15.08) for CPA/EE use compared with an OR(adj) of 2.58 (95% CI 1.60-4.18) for use of conventional COCs. CONCLUSIONS: We have demonstrated an increased risk of VTE associated with the use of CPA/EE in women with acne, hirsutism or PCOS although residual confounding by indication cannot be excluded.

Acne Vulgaris↗
PubMed1990

Temporal dimensions of the fertility transition: an age-period-cohort analysis of frontier fertility.

"This paper evaluates age, period, and cohort effects on marital fertility during onset of the Utah fertility transition (1880-1900). Computerized genealogies are used to derive age-period-cohort fertility rates for 49,842 once-married couples. Age, period and cohort effects on marital fertility are then estimated using Johnson's (1985) relational model. Declining marital fertility in Utah is shown to be explained by both lower fertility levels across periods and increasing age-specific limitation across cohorts. Direct cohort effects on fertility are insignificant. These results are consistent with prior research, and the view that fertility levels were adaptive (in part through birth spacing across ages) to immediate contexts of childbearing while age-specific fertility truncation increased across cohorts (in part through the more general diffusion of contraceptive innovations)."

Age Factors↗
PubMed2004

Matched-cohort analysis of patients with prostate cancer followed with observation or treated with three-dimensional conformal radiation therapy.

OBJECTIVES: To compare the outcome of similar patients with prostate cancer treated by either observation or three-dimensional conformal radiation therapy (3-DCRT). PATIENTS AND METHODS: The study included 69 patients with nonmetastatic prostate cancer who were observed only; the indications included indolent disease, significant medical comorbidities and refusal of treatment. Of these, 62 patients had palpable T1-T2a and seven T2b-T3a disease, a median Gleason score of 6 and a median initial prostate-specific antigen (PSA) level of 5.3 ng/mL. A matched-cohort analysis of 69 patients, based on palpation T category, Gleason score and initial PSA, was used to compare the outcome between the observation and 3-DCRT groups. The median radiation dose for latter was 72 Gy. RESULTS: The median follow-up for the observed patients was 49 months. The 5- and 8-year actuarial rates of freedom from distant metastases were 100% and 93%, respectively, and the actuarial overall survival rates 94% and 73%, respectively. Seven observed patients had local disease progression on physical examination. Four patients who initially were observed received radiation therapy later for a rising PSA and/or local disease progression. For the 69 matched 3-DCRT patients, the overall 5-year rate for no biochemically evident disease was 74%. The respective 5- and 8-year actuarial rates of freedom from distant metastases were 95% and 95%, and actuarial overall survival rates 95% and 75%. There were no significant differences in distant metastasis and overall survival rates between the groups, and no deaths from prostate cancer in either group. CONCLUSIONS: Observation is a reasonable alternative to treatment in selected patients. During the 5-year follow-up the progression rates were relatively low, and there was no difference in distant metastasis or overall survival between the groups. As the follow-up was short a longer follow-up is needed to determine whether the outcome of those patients who chose observation will remain comparable to that in those undergoing immediate 3-DCRT.

Adenocarcinoma↗
PubMed2006

Search for low penetrance alleles for colorectal cancer through a scan of 1467 non-synonymous SNPs in 2575 cases and 2707 controls with validation by kin-cohort analysis of 14 704 first-degree relatives.

To identify low penetrance susceptibility alleles for colorectal cancer (CRC), we genotyped 1467 non-synonymous SNPs mapping to 871 candidate cancer genes in 2575 cases and 2707 controls. nsSNP selection was biased towards those predicted to be functionally deleterious. One SNP AKAP9 M463I remained significantly associated with CRC risk after stringent adjustment for multiple testing. Further SNPs associated with CRC risk included several previously reported to be associated with cancer risk including ATM F858L [OR=1.48; 95% confidence interval (CI): 1.06-2.07] and P1054R (OR=1.42; 95% CI: 1.14-1.77) and MTHFR A222V (OR=0.82; 95% CI: 0.69-0.97). To validate associations, we performed a kin-cohort analysis on the 14 704 first-degree relatives of cases for each SNP associated at the 5% level in the case-control analysis employing the marginal maximum likelihood method to infer genotypes of relatives. Our observations support the hypothesis that inherited predisposition to CRC is in part mediated through polymorphic variation and identify a number of SNPs defining inter-individual susceptibility. We have made data from this analysis publicly available at http://www.icr.ac.uk/research/research_sections/cancer_genetics/cancer_genetics_teams/molecular_and_population_genetics/software_and_databases/index.shtml in order to facilitate the identification of low penetrance CRC susceptibility alleles through pooled analyses.

Aged↗
PubMed1998

"An empire lost but a province gained": a cohort analysis of British international retirement in the Algarve.

"The growth of international retirement in the Algarve has coincided with a number of changes in the international framework for population mobility as well as in the nature of the Algarve [Portugal] as a destination area. Tourism development, which is intimately linked to subsequent retirement migration, is particularly important in this. This paper considers the nature of the link between cycles of migration and of development in recipient areas, in the context of the remarkable and relatively late development of the Algarve as an area of tourism and retirement.... Cohort analysis...provides the basis for an examination of changes over time in the socio-demographic profiles of the migrants, their motivations, their residential patterns and their integration."

Acculturation↗