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PubMed1996

A quantitative analysis of symptoms of non-ulcer dyspepsia as related to age, pathology, and Helicobacter infection.

BACKGROUND: Non-ulcer dyspepsia (NUD) has been attributed to gastritis and Helicobacter infection. The Sydney classification enables dyspepsia symptoms to be assessed quantitatively in relation to Helicobacter infection and topographic pathology in different gastric compartments. METHODS: In this study of 348 patients with NUD we studied the unconfounded effects of age, pathology, and Helicobacter. Endoscopic findings, dyspeptic symptoms, and age were recorded prospectively. Multiple logistic regression was used to evaluate the independent effects of age, pathology, and Helicobacter. RESULTS: Ulcer-like pain was negatively related to age (odds ratio = 0.75/10 years; P < 0.001). A high density of Helicobacter at the antrum but not elsewhere in the stomach was positively related to ulcer-like pain (odds ratio = 3.38; P < 0.002). Adjusted for age, none of the endoscopic (P > 0.19) and histopathology findings (P > 0.09) played an important role in NUD. CONCLUSION: Age was the most important determinant of dyspeptic symptoms, but not pathology or Helicobacter.

Abdominal Pain↗

PubMed1993

Risk factors for tumor recurrence and prognosis after curative resection of hepatocellular carcinoma.

METHODS: Eighty-three patients with hepatocellular carcinoma (HCC) were treated with curative surgical resection during the past 8 years. RESULTS: No operative deaths occurred. The cumulative recurrence rates after resection at the ends of years 1, 2, and 3 were 37.0%, 57.1%, and 71.6%, respectively. After adjusting the imbalance in clinical factors among patients by using a Cox proportional-hazards model, it was shown that multiplicity, histologic classification, and absence of antibody to hepatitis C virus were associated significantly with recurrence after resection. The size of the tumor did not affect the incidence of recurrence. Thirty-eight of 41 patients with intrahepatic tumor recurrence had undergone at least one of the following three therapies against HCC: surgical reresection, percutaneous ethanol injection (PEI), and transcatheter arterial embolization (TAE). The most significant factor affecting the survival time of patients with tumor recurrence was the total number of tumor nodules at the time of recurrence. Although surgery and PEI were thought to be more effective treatments than TAE in prolonging life, multivariate analysis showed that they were not significant factors of survival time because choices in the method of treatment were correlated closely with the number of cancer nodules. A 65.3% 5-year survival rate from the time of first surgery was accomplished through vigorous therapy when tumors recurred. CONCLUSION: In conclusion, despite the high recurrence rate after resection of HCC, the use of multiple therapies can achieve increased survival rates.

Adult↗

PubMed2000

[Diagnostic criteria and new classification of the cervical spine syndrome].

OBJECTIVES: Pain and functional disorders of the neck are widely diagnosed as "cervical spine syndrome". As this diagnosis is not able to sufficiently specify the different symptoms, a new classification with five pain syndromes, created empirically, was developed. The aim of this study is to evaluate the predictive values of the diagnostic criteria respectively clinical findings of patients diagnosed with cervical spine syndrome. METHODS: Within the two year time frame of the study all patients diagnosed with "cervical spine syndrome", which presented themselves at the clinic, were included. The statistic analysis was performed in multiple steps: univariate analyses, bivariate variable screening and the use of the logistic regression model. RESULTS: Within two years 653 patients previously diagnosed as suffering from cervical spine syndrome presented at the clinic; 332 of them were included in the study. According to the diagnostic criteria they were attached to one of the five pain syndromes. The statistical analysis showed in 17 of 35 evaluated diagnostic criteria a significant association to one of the five subgroups of the cervical spine syndrome. CONCLUSION: The statistical analyses revealed significant associations between diagnostic criteria which were assessed by clinical examination and the five subgroups of the cervical spine syndrome. The identified predictors represent the typical syndrome-associated diagnostic criteria of a certain syndrome-subgroup.

English Abstract↗

PubMed2002

Nocturnal polyuria versus overactive bladder in nocturia.

The purpose of this article is to review the current state of knowledge on contributions of nocturnal urine overproduction and overactive bladder to the syndrome of nocturia. We review the recent literature and current state of the art in differential diagnosis, pathophysiology, and classification of nocturia. We found that multiple pathologic factors may result in nocturia, including cardiovascular disease, diabetes mellitus or insipidus, third spacing of fluid, sleep apnea, lower urinary tract obstruction, primary sleep disorders, and behavioral and environmental factors. Thus, nocturia may be attributed to nocturnal polyuria (nocturnal urine overproduction), diminished nocturnal bladder capacity, or both. Distinction between these conditions is made by a simple arithmetic analysis of the 24-hour voiding diary. Understanding the manifold origins of nocturia will lead to rational treatment of specific contributing pathophysiologic factors.

Aged↗

PubMed2002

Body mass index and waist circumference independently contribute to the prediction of nonabdominal, abdominal subcutaneous, and visceral fat.

BACKGROUND: It is unknown whether the ability of waist circumference (WC) to predict health risk beyond that predicted by body mass index (BMI) alone is explained in part by the ability of WC to identify those with elevated concentrations of total or abdominal fat. OBJECTIVE: We sought to determine whether BMI and WC independently contribute to the prediction of non-abdominal (total fat - abdominal fat), abdominal subcutaneous, and visceral fat. DESIGN: Fat distribution was measured by magnetic resonance imaging in 341 white men and women. Multiple regression analysis was performed to measure whether the combination of BMI and WC explained a greater variance in non-abdominal, abdominal subcutaneous, and visceral fat than did BMI or WC alone. These fat depots were also compared after a subdivision of the cohort into 3 BMI (normal, overweight, and class I obese) and 3 WC (low, intermediate, and high) categories according to the classification system used to identify associations between BMI, WC, and health risk. RESULTS: Independent of age and sex, the combination of BMI and WC explained a greater variance in non-abdominal, abdominal subcutaneous, and visceral fat than did either BMI or WC alone (P < 0.05). For non-abdominal and abdominal subcutaneous fat, BMI was the strongest correlate; thus, by adding BMI to WC, the variance accrued was greater than when WC was added to BMI. However, when WC was added to BMI, the added variance explained for visceral fat was greater than when BMI was added to WC. Furthermore, within each of the 3 BMI categories studied, an increase in the WC category was associated with an increase in visceral fat (P < 0.05). CONCLUSIONS: BMI and WC independently contribute to the prediction of non-abdominal, abdominal subcutaneous, and visceral fat in white men and women. These observations reinforce the importance of using both BMI and WC in clinical practice.

Abdomen↗

PubMed2004

DNA damage studies in untreated and treated leprosy patients.

The alkaline single cell gel electrophoresis assay was performed on peripheral blood lymphocytes of lepromatous and tubercloid leprosy patients (untreated and those undergoing treatment) in order to ascertain whether differential damage to DNA occurs. The study group included 28 male and 2 female patients and 15 healthy males who were matched for age and socio-economic status. The results revealed DNA damage in all patients, with a mean DNA migration length of 29.88 +/- 3.39 microm and 38% of their cells damaged when compared with the respective values obtained in healthy controls (1.28 +/- 0.40 microm, 5%). Multiple regression analysis for effects of confounding factors revealed antibiotic treatment in patients and alcohol consumption in controls as the only variables influencing DNA damage. In lepromatous and tubercloid patients, both untreated and those undergoing treatment, DNA damage increased significantly from that observed in control individuals, with greater increased damage in lepromatous patients. An increase in treatment time increased DNA damage linearly. Furthermore, an arbitrary classification of damaged cells (categories I-IV) was made based on observed tail lengths in leprosy patients (5.00-225.00 microm). The number of damaged cells in untreated patients was lower than in those undergoing treatment; the latter also had more cells with greater DNA migration lengths. There were no category III or IV cells in the control group. The results of the study therefore reveal that patients undergoing therapy had significantly greater DNA damage than untreated patients, indicating bacterial infection and drug therapy as the causal factors, since lepromatous-type disease is the more severe form with the patients having lower resistance to Mycobacterium leprae and requiring heavier and prolonged dosage of antibiotics. The study also corroborates that the assay offers an opportunity for correlating levels of therapy-induced DNA damage with administered dose and for modulating the dose-schedule so as to achieve lower levels of genotoxic damage.

Adolescent↗

PubMed2001

Treatment of proximal humeral fractures by intramedullary Kirschner wires.

BACKGROUND: This study is a retrospective analysis of a case series of 41 proximal humeral fractures treated by multiple intramedullary Kirschner (K) wires. METHODS: Forty-one proximal humeral fractures in patients aged 17 to 62 years were treated by closed intramedullary K-wires. There were 18 patients with the 2-part fractures, 11 with the 3-part fractures and 12 with the 4-part fractures according to Neer's classification. Patients were placed supine on the table, under general anesthesia. The arm was held vertically up by transolecranon traction, and the C-arm was kept parallel to the ground and opposite to the affected arm. A cortical window was created approximately 1.5 cm proximal to the olecranon fossa, by splitting the triceps. Under fluoroscopic control, multiple K-wires were introduced retrograde into the medullary cavity to reach the humeral head across the fracture. The wire tips were kept divergent to provide rotational stability at the fracture site. Postoperatively, the limb was supported in an arm sling. The patients were evaluated for pain, range of motion, strength, anatomic restoration, function of the involved limb, and radiographic union of fracture. RESULTS: An objective evaluation of the results using Neer's criteria showed 92.7% excellent to satisfactory results. Three patients developed painful shoulder-one from the 3-part and two from the 4-part fracture group. One patient from the 4-part group developed avascular necrosis of the humeral head. CONCLUSION: This surgical technique is effective for proximal humeral fractures. It is recommended for routine management of the 2-part and the 3-part fractures. For the 4-part fractures, it can be used in selected, young and active patients. An endoprosthesis is advised for the old, osteoporotic patients.

Adolescent↗

PubMed2006

Feed-forward support vector machine without multipliers.

In this letter, we propose a coordinate rotation digital computer (CORDIC)-like algorithm for computing the feed-forward phase of a support vector machine (SVM) in fixed-point arithmetic, using only shift and add operations and avoiding resource-consuming multiplications. This result is obtained thanks to a hardware-friendly kernel, which greatly simplifies the SVM feed-forward phase computation and, at the same time, maintains good classification performance respect to the conventional Gaussian kernel.

Algorithms↗

PubMed2005

ROCPLOT: a generic software tool for ROC analysis and the validation of predictive methods.

UNLABELLED: Receiver operating characteristic (ROC) analysis is a powerful and widely used technique for assessing predictive methods, yet there are no generic, open-source software tools for this that are freely available. Our ROCPLOT program performs ROC analysis on one or more files of search results (hits) and generates the following: (i) ROC values, giving a convenient numerical measure of method sensitivity and specificity; (ii) ROC plots graphically displaying sensitivity and specificity; (iii) classification plots to aid interpretation of the ROC plots and values; and (iv) a bar chart of the distribution of ROC values. ROCPLOT is generic and flexible: data in multiple hits files can be processed in series or parallel, allowing the results of multiple predictions to be viewed side-by-side or combined. AVAILABILITY: ROCPLOT is freely available for download as part of the European Molecular Biology Open Software Suite, EMBOSS (http://emboss.sourceforge.net/apps/rocplot.html).

Computer Graphics↗

PubMed2006

Prognostic value of phospholipase A2 group II, C-reactive protein and Simplified Acute Physiological Score II in intensive care patients.

We investigated the prognostic value of group II phospholipase A2 (PLA2-II) and C-reactive protein (CRP) in patients of the intensive care unit (ICU) who developed severe inflammatory reaction. In addition, the biochemical markers were correlated with the Simplified Acute Physiological Score II (SAPS II). Our study comprised 40 patients with multiple injuries and 35 patients with sepsis admitted to the ICU, and assessed during a follow-up of as long as 28 days. There were 18 survivors and 17 non-survivors in the sepsis group, and 22 survivors and 18 nonsurvivors in the group of patients with multiple injuries. In the group of patients with multiple injuries, the intensity of host inflammatory response showed clearly distinct PLA2-II and CRP profiles: the overall levels of PLA2-II and CRP were significantly higher in non-survivors than in survivors. PLA2-II and CRP do not discriminate nonsurvivors from survivors with sepsis. ROC (receiver operating characteristic curve) analysis and the area under the curve (AUC) showed the best classification of polytrauma patients with SAPS II and PLA2-II. In the group of patients with sepsis, only SAPS II appeared to be the most helpful predictive measure regarding patient outcome.

Adult↗

PubMed1984

Interpretation of statistical methodology associated with maintenance trials.

Maintenance trials in ulcer disease provide a scientific framework through which the prophylactic performances of two or more therapies can be compared with respect to ulcer recurrence. For this purpose, a primary source of data is the endoscopic classification of patients at protocol-scheduled visits as well as at unscheduled visits. Several statistical issues are relevant to the analysis of this endoscopic information. First, the extent to which the respective patients have different data patterns for their ulcer recurrence status must be taken into account by actuarial methods that adjust for the length of follow-up time. Second, the role of multiple investigators requires careful attention when information is combined from them. A third issue is concerned with the assessment of the variation of ulcer recurrence experience across subgroups with respect to patient demographics, medical history, and baseline characteristics. Statistical methods can effectively address these issues so that the results of maintenance studies can be interpreted through estimates for ulcer recurrence rates. In this way, they can meaningfully support clinical conclusions about the performance of alternative therapies for maintaining the absence of ulcer disease over time.

Actuarial Analysis↗

PubMed1984

[Analysis of prognostic factors in plasmacytoma].

For analysis of prognostic factors the clinical course of 109 patients with multiple myeloma was evaluated. Survival curves of immunoglobulin (Ig)G- and IgA-myelomas were identical (Fig. 1) with median survival times of 52 and 42 months, respectively, whereas patients with IgD- and Bence-Jones-myeloma had short survival times (median 3 months). Most important risk factors were anemia, renal insufficiency, and hypercalcemia (Figs. 7 and 8). Median survival time dropped from 52 months (Hb above 100 g/l) to 22 (Hb 85-100 g/l) and 1 month (Hb below 85 g/l). Patients with serum creatinine values below 2 mg/dl lived significantly longer than those with values above. Median survival times were 52 and 1 month, respectively. All seven hypercalcemic patients had a renal insufficiency and were in a very poor condition; their median survival time was 1 month. Analysis of the widely used staging system of Durie and Salmon gave disappointing results. Survival curves of the three A-stages ran close together with median survival times of 58, 51, and 36 months. Only the A-B classification according to renal function (A: creatinine under 2 mg/dl; B: creatinine above 2 mg/dl) proved prognostically relevant.

Aged↗

PubMed2003

Comparison of data analysis tools for detection of glaucoma with the Heidelberg Retina Tomograph.

PURPOSE: To evaluate the performance of three linear discriminant functions (LDFs) and the Moorfields Regression Analysis (MRA) in classifying optic disc topography images obtained with the Heidelberg Retina Tomograph (HRT) from patients with open-angle glaucoma and normal controls. Furthermore, to investigate whether the classification of glaucomatous eyes is related to the severity of visual field loss or to optic disc size. DESIGN: Prospective comparative observational case series. PARTICIPANTS: One eye of 104 patients with a diagnosis of open-angle glaucoma (mean age, 63.2; range, 30-88 years) and 48 normal controls (mean age, 52.4; range, 33-75 years). TESTING: Subjects were examined with the HRT. MAIN OUTCOME MEASURES: Diagnostic performance was calculated for the LDFs published by Mikelberg et al (LDF1), Burk (LDF2), and Bathija et al (LDF3) and for the MRA. RESULTS: Large differences in sensitivity and specificity were found among the different analyses when using the originally suggested cutoff criteria. When specificity was equalized to 90%, the sensitivities were more similar (LDF1, 55%; LDF2, 61%; and LDF3, 67%). At 95% specificity, the sensitivities decreased further (LDF1, 39%; LDF2, 55%; LDF3, 44%). When treating the "borderline" outcomes as test positives, MRA sensitivity and specificity were 78% and 81%, respectively. When treating the "borderline" outcomes as test negatives, the MRA gave a sensitivity of 58%, with a specificity of 96%. In glaucoma patients, the correlation between the severity of visual field damage, as measured by the mean deviation index, and the outcome of the classification systems was low to moderate (Spearman's r between 0.26 and 0.39). When the entire sample was stratified into equal thirds on the basis of optic disc size, large discs (area > 2.10 mm(2)) tended to be classified with a higher sensitivity but lower specificity than small discs (area < 1.73 mm(2)) with all methods except LDF3. Using a multiple regression model controlling for mean deviation, LDF1, and LDF2, but not LDF3, were significantly influenced by disc size. CONCLUSIONS: The 4 methods of analysis had similar sensitivities once their specificities were equalized. In this sample, the LDFs and MRA generally did not discriminate between glaucoma patients and controls as well as reported in the original respective studies that described the methods.

Adult↗

PubMed1999

A profile analysis of personality disorders: beyond multiple diagnoses.

The authors applied cluster analysis and multidimensional scaling to the analyses of 59 patients with personality pathology. Cluster analysis yielded eight typologies of patients: detached, anankastic, phobic, dramatic, erratic, emotional, milder emotional, and masochistic negativistic. Multidimensional scaling identified the dimensions of classifying patients: anxious rumination versus behavioural acting out, overall severity of personality pathology, and assertiveness versus withdrawal. Considering the distinction between personality disorder (dysfunctional personality) and abnormal personality (extreme personality), the following changes in current classification system are proposed: use of a hierarchy and exclusion criteria in a categorical-type model or use of a personality profile in a dimensional-trait model, in either case, with a dimensional rating for severity of psychopathology to define personality 'disorder'.

Adult↗

PubMed1996

Classification of temporomandibular joint sounds based upon their reduced interference distribution.

Temporomandibular joint (TMJ) sounds were recorded in 98 orthodontic retention patients, mean age 19 +/- 8.6 (s.d.) years, by interview, auscultation and electronic recording. Sounds were found by auscultation in 41% and by interview in 32% of the subjects, more often in females than in males (P < 0.05). A new method for time-frequency analysis, the reduced interference distribution (RID), was used to classify the electronic sound recordings into five subclasses, RID types 1-5, based upon location and number of their energy peaks. RID types 1-3 had a few energy peaks close in time. RID types 4-5, typical of subjects with crepitation, had multiple energy peaks occurring close in time for a period of 20-300 ms. RID type 1, found in 45% of the subjects, typical of patients with clicking, had its dominant energy peak located in a frequency range < 600 Hz and was significantly more common in the female than in the male subjects (P < 0.01). RID type 2, found in 68% of the subjects, with the dominant peak in the range 600-1200 Hz, and RID type 3, found in 38% of the subjects, with the peak in the frequency range > 1200 Hz, were found to have a similar gender distribution. RID type 4, found in 49% of the subjects, had the energy peaks distributed in the frequency range < 600 Hz. RID type 5, found in 43% of the subjects, more often in females than in males (P < 0.05), had the peaks distributed over the whole frequency range from about 30 Hz up to about 3000 Hz. In conclusion, a more detailed classification could be made of the TMJ sounds by displaying the RIDs than by auscultation. This suggests that RID classification methods may provide a means for differentiating sounds indicating different types of pathology.

Adolescent↗

PubMed1986

Auditory brain stem response test battery for multiple sclerosis patients: evaluation of test findings and assessment of diagnostic criteria.

A battery of auditory brain stem response (ABR) tests has been used to evaluate 39 multiple sclerosis (MS) subjects (9 with probable, 8 with possible, 6 with suspected and 16 with definite MS, according to conventional classification of the disease). Test battery included evaluation of ABR waveform, latencies and interpeak intervals, test-retest variability, rate-induced ABR changes, binaural increase of wave-V amplitude and effect of ipsilateral masking with broad-band noise. Test results allowed a measure of the sensitivity, specificity and efficiency of each test in the battery. The high efficiency values thus obtained validated each test in the battery when normals were compared with definite MS patients. No single test, however, proved to be sufficient--by itself--to reliably distinguish subjects with earlier stages of the disease, suggesting that a combined evaluation of tests is necessary to fit better the clinical classification. When compared with 'conventional' ABR analysis, 'sensitized' ABR tests--i.e. the measures of test-retest variability, binaural increase of wave-V amplitude and the effect of ipsilateral broad-band noise masking--showed higher percentages of positive results in subjects with no clinical signs of brainstem and midbrain involvement. Sensitized tests therefore appeared more suitable to reveal a brainstem subclinical involvement.

Adolescent↗

PubMed1999

Predictive model of functional independence in stroke patients admitted to a rehabilitation programme.

OBJECTIVE: To develop a prognostic model to estimate the probability of patients being independent in ambulation and in activities of daily living (ADL) after six months of stroke. DESIGN: Cohort analytical study. SETTING: Rehabilitation departments of two district general hospitals. SUBJECTS: Ninety-two consecutive stroke patients admitted to a rehabilitation programme. MAIN OUTCOME MEASURES: Independent ambulation was defined as a Functional Ambulation Classification (FAC) > or =4, and the independence in ADL as a Barthel Index (BI) > or =285. All patients were assessed on admission to rehabilitation, and in the first, second, third, fourth and six months after stroke. RESULTS: Prognostic factors were identified by means of a multivariate survival analysis using Cox regression. Three variables were predictors for a FAC > or =4: (1) The patients in the motor (M), motor-sensitive (MS) and motor-sensitive with hemianopsia (MSH) groups (relative risk (RR) 5.43 of M with respect to MSH, and 2.41 of MS to MSH). (2) A Motricity Index >25 (RR 3.19). (3) An age <70 years old (RR 1.99). For a BI > or =85 three predictors were selected: (1) The classification M-MS-MSH (RR 6.02 M to MSH, and 1.52 MS to MSH). (2) An initial BI >20 (RR 3.45); the highest contribution in the achievement of an initial BI >20 was bowel and bladder continence. (3) The antecedent of previous independence (RR 2.68). The predictive models, constructed by means of multiple logistic regression correctly classified 77% and 79% of the patients who obtained FAC > or =4 and a BI > or =85 respectively. CONCLUSIONS: The syndromic classification M, MS and MSH, together with other routinely available data, such as the Motricity Index, BI, the age and the previous functionality, can be used to obtain a patient prognosis level with regard to ambulation and ADL independence.

Activities of Daily Living↗

PubMed2002

[Classification of physical activity and health related variables in men].

OBJECTIVES AND METHODS: In this study, the relationship of physical activity with aerobic capacity and health checkup results were examined among 288 men aged 45.7 (mean) +/- 8.13 (SD) years. Physical activity was evaluated from a 3-day activity record and expressed as metabolic-equivalent (MET) (/day). Total caloric intake was evaluated from a 3-day dietary record. VO2 max was measured as the index of aerobic capacity, and body mass index (BMI), waist-hip ratio (WHR), % fat, and increase in body weight from 20 years old were used as indices of body composition. RESULTS: In multiple regression analysis, MET value, % fat, WHR and increase in body weight from 20 years old were independently and significantly associated with VO2 max. As MET value was a significant predictor, it may be important to evaluate physical activity not only during leisure time, but also throughout the whole day. In addition, preventing total body fat and abdominal fat increase seemed important to maintain and to increase aerobic capacity. To grasp the pattern of physical activity more precisely, subjects were classified into 6 groups (A: sedentary, B: sedentary + walking, C: sedentary + brisk walking, D: sedentary + exercise, E: active, F: active + exercise), and each variable was compared using one-way analysis of variance and post-hock test analysis (Tukey method). MET value increased in the order of groups A, D, E and F. Groups D and E showed no significant difference in the VO2 max and MET value, while both groups showed significantly higher values than those of group A. Therefore, aerobic capacity differed not only according to the presence of habitual exercise, but also according to whether the subjects had an active daily life. When sedentary, it seemed important to be active for about 1-hour/day. Regarding body fat, group F showed the lowest value in each variable. Systolic and diastolic blood pressures, and blood triglyceride levels were highest in group A and lowest in group F, suggesting the effects of an active daily life and habitual exercise. In group A, the total caloric intake was also highest. Therefore, improving the total lifestyle, including diet, was also considered necessary. CONCLUSIONS: Classification of subjects according to their pattern of physical activity may be useful in health education settings to increase physical activity and to prevent life-style-related diseases.

Activities of Daily Living↗